Anyone swapped a 3.9 out of a G6? they have the same amount of power as the 3800sc II. I can find the 3.9's with way less miles for the same price as a 3800sc.. what do ya guys think?

quote Originally posted by 87GTV6: Anyone swapped a 3.9 out of a G6? they have the same amount of power as the 3800sc II. I can find the 3.9's with way less miles for the same price as a 3800sc.. what do ya guys think?

Aaaaahahaha!

Do a search for 3900 or my user name or name to get some info, I don't have immediate access to the links at the moment.

quote Originally posted by 87GTV6: Anyone swapped a 3.9 out of a G6? they have the same amount of power as the 3800sc II. I can find the 3.9's with way less miles for the same price as a 3800sc.. what do ya guys think?

Actually, we 3800SC II boys get 40 more ft-lbs, if I recall correctly. :P
Just knit-picking; I mean no offense.

As Joseph mentioned, it's definitely been done before. I don't know the specifics on the swap, like how difficult it is as opposed to the 3800SC, but I'm sure someone here has documented their swap.

The Fiero community is still slowly accepting the easiest path to more baseline power in their naturally aspirated V6 swaps, than the most powerful on average. For example, the 3800SC is only marginally more powerful than the 3900 in its naturally aspirated form and GM built a HO 3900 that produced 270 hp with a cam change and a little cylinderhead work. It's not more difficult to adapt this engine than the 3800, it requires some extra simple available parts for link up to the Fiero but not significantly more and the 3500 and 3400 swaps have been proven performers. The 3800 and 3.4L are just good, common, well documented swaps needing little to no tuning so that's what you see most of.

https://www.fiero.nl/forum/Forum2/HTML/107886.html
https://www.fiero.nl/forum/Forum2/HTML/084972.html

the first thing i notice from what has been posted is the heads flow realy good and if one was to get the right cam and turbo it should be able to make as much if not more power than the 3800 with a turbo but you must have the high lift .600 +

[This message has been edited by engine man (edited 02-04-2011).]

quote Originally posted by engine man: the first thing i notice from what has been posted is the heads flow realy good and if one was to get the right cam and turbo it should be able to make as much if not more power than the 3800 with a turbo but you must have the high lift .600 +

You don't need high lift for heads that already outflow 3800 heads. I've seen a pretty good trend suggesting just the opposite. Depends on what you're trying to do. I hope to have numbers before long but I'm sure my car is as fast now with just the compression and stroke increase than the engine was on 7 psi before the upgrades. The asterisk however is that the cam was not degreed in during the first test under boost. There is no question however that it comes off the line much quicker eventhough I have the wastegate wide open preventing boost for now. Don't forget, the HO motor already makes more hp naturally aspirated than the stock 3800SC. It just falls a little short on torque but I believe as mentioned that was to protect the weak dualmass flywheel which is torque limited.

[This message has been edited by Joseph Upson (edited 02-04-2011).]

you know with all the engine combos for the fiero i just want one of them all 4 Banger to big block V8 it sure makes it tough on a guy on what to do LOL

You may want to try getting a 3.9 outta a impalla 9c1. Cops are great drivers, so there easy and cheep to get at a scrapyard. I have got one in (with the 4 speed auto), now to do the computers. but its cold out...

and for you 3.8 sc guys, how wide is your torque curve? Ive got 200+ ft-lb between 1500 to 5500 (VVT!) but then you do have a sc, and the 3.9 does not.

Matt

Actually us 3800 guys get 2-3 times the power over a 3900

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Turbo 3800 E85 5spd spec5
11.53@126.7

[This message has been edited by Justinbart (edited 02-05-2011).]

For building a 1/4 mile car: between a 60 degree v6 and a 3800, the 3800 is a smarter option hands down. Its comes with a stronger bottom end, and once boost is an option, the 3800 will be able to make much more power before stuff starts breaking, regardless that the new 60 degree engines are more efficient (better flowing heads). Just crank up the boost and put down loads of power end of story.

However, the 60 degree has something else to offer if you want a drivers car. First of all it has a much sweeter exhaust sound. That is important in drivers car. It is a better platform in a lot of ways for NA. Big numbers can be put down with simply a cam and headers. It has the capability of more MPGs as it is a more efficient engine. It is a very light engine. The 60 degree engine leaves more room in the engine bay compared to a 90 degree. These can be found nearly brand new for dirt cheap. Did I mention it sounds way cooler..

In conclusion:

3800: unbreakable stock bottom end + boost = endless cheap power

Modern 60 Degrees: other (trivial?) qualities.... <-- But this is the one I prefer

[This message has been edited by LZeppelin513 (edited 02-05-2011).]

It's funny this thread came up, I've been working on a spreadsheet all evening which has 24 swap candidate engines compared head to head.

I think it's important to put things into relativity.

A 3800 Series 2 / 3 that's NA makes ------- : 205hp / 230 tq
A 3900 ---------------------------- makes: 240hp / 240 tq
A 3800 Series 2 with the GenIII M90 makes: 240hp / 280tq
A 3800 Series 3 with the GenV M90 makes: 260hp / 280tq


Now, lets use the cheaper boosted 3800; the Series II. If we put $100 towards a 3.4 pulley and cooler plugs we arrive at: 260hp / 300 tq. Now, we have other things to consider; the supercharged engine requires premium fuel, the 3900 sounds better, the 3800 is much more reliable, et cetera. Consider that boosting the 3900 will require fabrication. While the M90 is garbage, it comes equipped on the 3800 and pushed torque up just enough to lead the candidate V6 engines list. It's also cheap to make power with, add a camshaft and tune to get to into 350hp/350tq territory with the M90. I don't think a 3900 is going to get there NA, and it's going to be expensive to start from scratch with boost. There is also a cam option from ZZP that adds 30 hp to the NA engine, which puts it along side the 3900 in hp and above it in torque. The 3800 actually sounds pretty good when using an exhaust much like the original Fiero exhaust. It sounds horrible when opened up.

It's really up to the individual and personal tastes. One engine isn't better than the other. I will say though, I do question the 3900's reliability based on the 3400's track record. That's enough to sway me to the 3800 NA for an economy swap. I'm tired of working on Fiero engines.

And to those talking about boosting the 3900, I think rods will go through the block at 22lbs of boost, which is what the 3800 laughs at.

quote Originally posted by L67: the 3800 and pushed torque up just enough to lead the candidate V6 engines list. It's also cheap to make power with, add a camshaft and tune to get to into 350hp/350tq territory with the M90. I don't think a 3900 is going to get there NA

The 3900 just might be able to hit those numbers NA. A guy on the cavalier forum had a 3500 old design dynoing 280hp to the wheels with just a cam headers and a port/polish.

Who knows till someone does it though (another cool thing about these engines)

That would certainly be interesting to see.

I checked car-part.com and couldn't find a 3900 for less than $700, very likely because its so new. I can buy series II 3800's for $150.00 (with warranty) all day long.

quote Originally posted by L67: And to those talking about boosting the 3900, I think rods will go through the block at 22lbs of boost, which is what the 3800 laughs at.

Based on what? You 3800 guys sound threatened.

Which engine is the smarter option depends on your skill level and equipment, as for which engine is stronger, nobody knows at this point because there are only 2 3900 Fieros that I'm aware of and there's just no rational behind saying the 3800 with it's two bolt main has a stronger bottom end than any of the aluminum oil pan 60s with cross bolted steel main caps and the latest engines with steel cranks. Nobody really knows at this point.

As for potential the 3800 SC is barely making more power than a naturally aspirated stock 3900 which GM has conservatively already produced 270 hp with. Matched upgrade for upgrade and there would likely be no comparison. It's a moot and rather reaching point when you have to compare a boosted version of an engine to a naturally aspirated version of another to make it competitive. The 3800 naturally aspirated barely out performs the 3500 which has been proven to put down serious numbers with a cam and head work. The 3800 is the easier and preferred swap because many here are afraid or unable to tackle tuning and wiring harnesses. That's my opinion on the matter, but practically speaking, when it's more power you are trying to achieve, you start with the highest base and potential in the engine range you want and improve on it.

ps
I ran 7 psi on 87 octane on the first engine.

[This message has been edited by Joseph Upson (edited 02-05-2011).]

how do you feel a 3900 with a Eaton 112 blower from a mustang would work 12psi bost and intercooled ?

quote Originally posted by L67: That would certainly be interesting to see. I checked car-part.com and couldn't find a 3900 for less than $700, very likely because its so new. I can buy series II 3800's for $150.00 (with warranty) all day long.

Your right about the 3.9 going for a bit (1600 for eng/tran) but how much lower are the miles? Mine is under 30,000 just broken in. I would rather pay more for a newer (lower mile) one than on that has been abused for 150,000.
Matt

I paid $200 for the engine I built into a stroker with 27K miles on it. You have to search well and bargain.

The burnt 3900 motor as well as all of my 3500 and 3900 engines that have had the cranks removed temporarily for the crank trigger wheel had bearings that looked like they were just put in the block. If it saw regular oil changes I wouldn't worry much about high miles given a more superior oiling system than the previous engines not to mention oil spray to help better lube the piston rings. Make sure you're not searching for the DOD motor which will very likely be more expensive.

quote Originally posted by 87GTV6: Anyone swapped a 3.9 out of a G6? they have the same amount of power as the 3800sc II. I can find the 3.9's with way less miles for the same price as a 3800sc.. what do ya guys think?

I swapped one, I think it's a good idea as long as you plan ahead. Like most swaps it'll be cheaper this way. The holdup is vvt and a single crank sensor. You can use a stock g6 computer and not have to worry about anything but antitheft which I don't think is really a problem anymore. I went the more expensive route and locked the cam and tuned with a 9396 pcm. This turned out to be a waste of time and money since it wasn't degreed in properly. I then installed a performance 3400 cam from wot-tech.com. This gave me the power it should have. I have a before and after dyno but can't get PIP to work on the new computer, Joseph can post it if he still has it or I can email it. I believe the power will be slightly higher this year because I redid the exhaust again because the previous setup was too close to the frame and pulling timing due to false knock and I had sinister go over the tune and swapped to the 3500 non-variable intake. Now I have good power and boost is still an option in the future. Choose carefully, and by that I mean use the G6 computer.

quote Originally posted by Joseph Upson: Based on what? You 3800 guys sound threatened.

Oh hell no.. If anything this is great information. I'm basing this on what I've seen 3400's do - leak coolant and die. The 3500 and 3900 are basically newer versions of the 3400, and I've never liked this. They just look.... weak. The cylinder heads for instance, and the staggered valves. I read about all the problems people have with them, and I see a nice fat 3800 sitting in the car next to the 3400 in the yard, check the odometer on the 3800 car and see 267,000 miles, and I'm in love with the 3800 all over again. I've worked on quite a few 60 degree's over the years, and none have really impressed me as much as how "meaty" the 3800 is. I have a friend who has a brand new '09 Impala with the LX9 (less than 50,000 miles), and I pointed out to him it was blowing black smoke out the tailpipe when he floored it getting onto the highway the other day. Little things like this concern me, that's all. Alternatives are great! The more variety the better!

The 3800 can make 400hp on a completely stock cam and heads and a cheap T61. Very few engines can do something like this one a 100k mile junkyard block. I've seen the video's you posted Joseph, of the twin turbo car making runs and the front end of your car lifting up several feet because of the shocks. It looks quick. I also remember helping Jncomutt tune his turbo 3800 on the highway, and making a 4th gear pull at 50mph and not being able to hold the laptop upright so that I could read the tables off to him. I don't think a stock 3900's going to be an absolute monster like that, based on how ****ing hard that engine pulls, and how weak the 3900 looks and the 3400's track record. If you do make some numbers like this, I'll be the first one to congratulate you. Part of having an education dictates that some real world data come into play before standing behind something, I'd just like to see some action before believing the hype (dyno numbers, drag strip pulls, longevity, and so forth). I've logged lots of hours in one of the fastest Fiero's in the world, and it was using a 3800 and a turbo, so I've got nothing but praise for it. I don't mean to degrade any other option or be disrespectful.

First let me say this the 3800 is a good engine Buick started to build V6 in the 60's but i think that every one is looking to find some thing better and make even more power will the 3900 do it i dont know the head flow # say it should but will it stay together who knows is the 3.6 dohc the engine dont know but i do know that the guys trying to find new power plants for the fiero are working hard to find another V6 to take the place of the 3800

quote Originally posted by L67: Oh hell no.. If anything this is great information. I'm basing this on what I've seen 3400's do - leak coolant and die. The 3500 and 3900 are basically newer versions of the 3400, and I've never liked this. They just look.... weak. The cylinder heads for instance, and the staggered valves. )

The only problems that matter are the ones that pertain to the engine being discussed whatever they may be. You can't use the 3400 intake system on the 3900 properly not to mention several other differences that limit the parts that can be swapped over. No coolant flows through the intake on the 3900 for example to associate with the 3400 problems which were mainly gasket related, and several of GMs early engines including V8s had piston slap problems but not anymore. Stick with the 3900 topic.

The 3900 produces more hp and tq than the NA 3800 bottom line. What's so hard to accept about that. no need to debate the obvious. Before long if not me someone else will produce results to help squash the assumptions based on earlier engines which lack the upgrades the 3.9 has. You wouldn't compare a 3.4 pushrod to the weaknesses of the 2.8L. would you. Appreciate the successor.

quote Originally posted by Joseph Upson: The 3900 produces more hp and tq than the NA 3800 bottom line. What's so hard to accept about that. no need to debate the obvious.

Sigh. Joseph I feel as though you're still confusing the way I feel about this. I'm well aware the 3900 makes more power and torque than the N/A 3800. I'm quite comfortable with this, I don't have any "problem" with this, I do appreciate this.

quote Originally posted by L67: A 3800 Series 2 / 3 that's NA makes ------- : 205hp / 230 tq A 3900 ---------------------------- makes: 240hp / 240 tq

I look forward to seeing this engine being used.

quote Originally posted by L67: I look forward to seeing this engine being used.

I see that your in NC. I am hoping that my swap is done soon (a few months?), and would like to see how it does compared to a 3.8sc. Would you be willing to meet and check it out when its done?
Matt

Sure! I'd be able to offer up a subjective opinion, if you were interested. I wouldn't have a supercharged 3800 Fiero to compare it with. I sold my old 3800 setup to a fellow in Durham. There's a boy in Raleigh who has made plans to bring me his car in the summer for an N/A 3800 swap, if that pans out, I'm sure he'd be a great person to locally compare with when finished.

The easiest approach I believe is to degree and lock the camshaft into place the way I demonstrated in the thread, but after you send the camshaft off for a performance regrind to extract a little more power.

Other than that it should be straightforward. The G6 PCM would be nice but it's still more expensive management wise because of what you would have to swap in place in order to support it. The tuning equipment would probably be more expensive than the OBD I equipment I suspect also.

It can be done pretty conveniently with OBD I though; manual throttlebody and adaptor, internal or external 7x trigger wheel, returnless fuel conversion or adapt 3400 rail, 730 ecm and that's about it. Tuning is assumed. That's about $250 worth of parts plus whatever you choose for tuning, pretty much the same for any other swap needing tuning afterwards.

[This message has been edited by Joseph Upson (edited 02-06-2011).]

Is there no support in HPtuners for the G6 yet?

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Turbo 3800 E85 5spd spec5
11.53@126.7

quote Originally posted by Joseph Upson: there's just no rational behind saying the 3800 with it's two bolt main has a stronger bottom end than any of the aluminum oil pan 60s with cross bolted steel main caps and the latest engines with steel cranks.

All 3800 Series 2 and 3 engines: N/A and SC, have cross bolted main caps that tie into the iron block. Furthermore the 3800 block is a deep skirt design which is far stronger than any GM 60 deg V6 design I've seen. I won't discount that the cast aluminum oil pan used on the "newer" 60 deg V6's with their cross bolted mains is strong. It does help a great deal (vs. earlier versions that used the stamped still oil pan and no cross-bolted mains), but I doubt it is AS strong as the 3800 Series 2 and 3 design.

quote As for potential the 3800 SC is barely making more power than a naturally aspirated stock 3900 which GM has conservatively already produced 270 hp with. Matched upgrade for upgrade and there would likely be no comparison. It's a moot and rather reaching point when you have to compare a boosted version of an engine to a naturally aspirated version of another to make it competitive. The 3800 naturally aspirated barely out performs the 3500 which has been proven to put down serious numbers with a cam and head work.

Peak numbers are great for bench racing but that's about it. What is more important is the torque curve and the amount of power the engine makes under the curve. This is the useful power the car needs to make it accelerate. The 3800 SC makes a ton of power under the curve. The 3500 and 3900 can also, but only with a functioning factory VVT system. Take that off and you'll need to do some serious mods (head work, cam, etc) in order to get a 60 deg V6 to hang with a 3800 SC. But more importantly there is the factor of cost. You talk about matching upgrade for upgrade but there is a difference when the same upgrades on a 3800 cost 1/2 as much or less to do than what they cost to you to on a 3500/3900; -OR- when the same priced upgrade on a 3800 SC will net me 20 more HP than the same priced upgrade on a naturally aspirated 3500/3900 that only nets you a 10hp increase.

I consider the 3500/3900 to still be a relatively "new" engine when we are talking about engine swaps. The 3800 SC is tried and true + it has more aftermarket support (currently) and is just cheaper to mod when we are talking about $$$ in and power gains out. If you want to talk about turbocharging then there's the question you raised yourself about just how strong is the bottom end of the 3500/3900? How much boost/power/abuse can it take? I don't care if it has forged steel parts here and there; those will do you little good if you break a piston (and for the record I've seen forged steel parts bend and break while I've seen cast iron parts survive at the same power level). It all comes down to the quality of the forging and the amount of load it is designed to take.

Don't misunderstand where I'm coming from here. I am impressed with the 3500/3900 60 deg V6 engines. I think there is some major potential there. But at this point in time the cost/benefit potential needs to be considered. And right now the 3800 SC (or turbo) cannot be beat by anything I've seen used in a Fiero when we are talking about cost : performance ratio. Now if you want to be different and don’t have tight budget constraints, then the field is wide open. But then that opens up the argument from people who would say why not just swap an LS7 or LS9 in there???

-ryan


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OVERKILL IS UNDERRATED

Custom GM OBD1 & OBD2 Tuning | Engine Conversions & more | www.gmtuners.com

[This message has been edited by Darth Fiero (edited 02-06-2011).]

I'm gonna get you Darth, upgrades are not expensive for this engine. My cam upgrade cost me less than 100 and the other necessary parts are available and pretty cheap, it didn't cost me anymore to make a turbo setup for this engine than it did any of the others. In theory though the 3800 probably is stronger but ultimately time will tell whether our desktop dishing is accurate or not.

None the less what the 3900 does naturally aspirated still makes what the 3800SC does on 7 psi much less impressive and the VVT is only needed for a broad torque range, and is mostly for emissions, there's no need to assume it wouldn't perform as well with the traditional configuration the 3800SC has. It has already been proven with the LS engines that they perform better with VVT delete. Time will tell, it's fun to trash talk for now though. Hope you have a 3.0 pulley because my car is so fast it's going to take two parachutes to stop me.

The 3.6 DOHC puts them all to shame.

quote Originally posted by Darth Fiero: Peak numbers are great for bench racing but that's about it. What is more important is the torque curve and the amount of power the engine makes under the curve. This is the useful power the car needs to make it accelerate. The 3800 SC makes a ton of power under the curve. The 3500 and 3900 can also, but only with a functioning factory VVT system. Take that off and you'll need to do some serious mods (head work, cam, etc) in order to get a 60 deg V6 to hang with a 3800 SC. But more importantly there is the factor of cost. You talk about matching upgrade for upgrade but there is a difference when the same upgrades on a 3800 cost 1/2 as much or less to do than what they cost to you to on a 3500/3900; -OR- when the same priced upgrade on a 3800 SC will net me 20 more HP than the same priced upgrade on a naturally aspirated 3500/3900 that only nets you a 10hp increase. I consider the 3500/3900 to still be a relatively "new" engine when we are talking about engine swaps. The 3800 SC is tried and true + it has more aftermarket support (currently) and is just cheaper to mod when we are talking about $$$ in and power gains out. If you want to talk about turbocharging then there's the question you raised yourself about just how strong is the bottom end of the 3500/3900? How much boost/power/abuse can it take? I don't care if it has forged steel parts here and there; those will do you little good if you break a piston (and for the record I've seen forged steel parts bend and break while I've seen cast iron parts survive at the same power level). It all comes down to the quality of the forging and the amount of load it is designed to take. Don't misunderstand where I'm coming from here. I am impressed with the 3500/3900 60 deg V6 engines. I think there is some major potential there. But at this point in time the cost/benefit potential needs to be considered. And right now the 3800 SC (or turbo) cannot be beat by anything I've seen used in a Fiero when we are talking about cost : performance ratio. Now if you want to be different and don’t have tight budget constraints, then the field is wide open. But then that opens up the argument from people who would say why not just swap an LS7 or LS9 in there??? -ryan

Now that you are here, what is your opinion on removing vats with a stock G6 PCM. A tune is there for auto and manual and no custom flywheel is required. It should be lighter although I can't back that up with fact, so there are upsides to the swap. I would like to see the motor become more popular but I also want to see one with a stock PCM as I think it would be more cost effective. If anyone is set on obd1 I can turn you to the first company that did my tune with the 9396. It would be a really good starting point and should also be cost effective. Darth also has my tune but you would probably want to copy my cam specs.

quote Originally posted by Joseph Upson: Hope you have a 3.0 pulley because my car is so fast it's going to take two parachutes to stop me.

You're talking about your car, the one with an engine in it that has a custom twin turbo setup? Not an N/A engine, but a twin turbocharged 3900? And you're calling out people using an M90'd 3800. Hilarious. Why don't you call out Justin? He's got a very "mild" 3800 turbo setup. You're right, you're just talking smack, and you're pretty much the only one in here doing it.

quote Originally posted by Joseph Upson: Time will tell, it's fun to trash talk for now though.

quote Originally posted by Joseph Upson: Based on what? You 3800 guys sound threatened.

I get it. I wasn't threatened at all, I was being practical. I think the 3900 is a great NA platform. Possibly even a good platform for moderate amounts of boost. But there's the alternative which is the 3800. The 60 degree rotating assembly isn't the strongest in the world, based on real world examples - certainly not even close to the 3800's bottom end.

What happened to your "first engine" by the way?

Semantics such as "you 3800 guys" ... Obviously you were projecting when you asked why 3800 owners would feel threatened. Do you feel threatened, if so why? The 3800 doesn't "belong" to any specific group of people. We're all in this together, no need to start any sort of division.

I used to ride along to the bars on weekends in college in a 600 hp Fiero, we didn't need parachutes. You're making more?

[This message has been edited by L67 (edited 02-06-2011).]

quote Originally posted by L67: I get it. I wasn't threatened at all, I was being practical. I think the 3900 is a great NA platform. Possibly even a good platform for moderate amounts of boost. But there's the alternative which is the 3800. The 60 degree rotating assembly isn't the strongest in the world, based on real world examples - certainly not even close to the 3800's bottom end. What happened to your "first engine" by the way? Semantics such as "you 3800 guys" ... Obviously you were projecting when you asked why 3800 owners would feel threatened. Do you feel threatened, if so why? The 3800 doesn't "belong" to any specific group of people. We're all in this together, no need to start any sort of division. I used to ride along to the bars on weekends in college in a 600 hp Fiero, we didn't need parachutes. You're making more?

It's all in good fun, don't mess it up by getting serious, or taking anything said in this context serious, because there really shouldn't be any talk in here about a 3800 if the thread title was taken seriously. Okay maybe a little. Relax.
My previous engine is fine sitting quietly aside with less than 10k miles on it waiting for an assignment.

[This message has been edited by Joseph Upson (edited 02-06-2011).]

That's cool. Just checking the tone.

quote Originally posted by Joseph Upson: I'm gonna get you Darth, upgrades are not expensive for this engine. My cam upgrade cost me less than 100 and the other necessary parts are available and pretty cheap, it didn't cost me anymore to make a turbo setup for this engine than it did any of the others. In theory though the 3800 probably is stronger but ultimately time will tell whether our desktop dishing is accurate or not. None the less what the 3900 does naturally aspirated still makes what the 3800SC does on 7 psi much less impressive and the VVT is only needed for a broad torque range, and is mostly for emissions, there's no need to assume it wouldn't perform as well with the traditional configuration the 3800SC has. It has already been proven with the LS engines that they perform better with VVT delete. Time will tell, it's fun to trash talk for now though. Hope you have a 3.0 pulley because my car is so fast it's going to take two parachutes to stop me. The 3.6 DOHC puts them all to shame.

The broad torque range is what wins a drag race. That's what the SC on the 3800 gives you and that's what the VVT on the 3900 gives you. Honestly I think it is a waste to get rid of it if your engine already has it. Why not take advantage of that technology? Since I don't know much about the VVT LS engines I can't comment much about your claims that "they perform better without VVT". I will say that the aftermarket (and general community) has proven to be pretty slow in getting up to speed on a lot of new technologies the automakers have developed. And their track record has commonly been to "badmouth" some of these new technologies they don't understand or are unfamiliar with. I'm willing to bet that in the long run, VVT will be seen as having a positive impact on performance as more people (and aftermarket companies) come to understand how the system works and how to exploit it to make the most power possible. I bet the same kind of negative stuff has been said about direct injection at some point too. I know it was said about EFI back in the 80’s, and look what we’re doing with it today…

The common non-direct injected 3.6 DOHC VVT engines produce about 250hp and 250tq. I wouldn't say that puts a 3800 SC to shame. The direct injected version produces 304hp and 273tq which is impressive, but there's a problem. There is NO aftermarket tuning support currently available for the ECMs that control this engine, at least none that I am aware of. Without it, you can forget about swapping one of these engines into a Fiero unless you are prepared to swap a whole lot of other electronics from the donor car in when you do the swap. This isn't going to make the swap easy (or cheap if you are paying someone else to do it). I HOPE support for these systems does come out soon and I hope it can disable VATS (and/or the need to have the BCM or any other modules present for the engine to run right). Besides that, how many of these DI engines do you see available in salvage vehicles and how much it would cost to get a hold of one?

I'm not trying to bust your chops here. I'm simply playing devil's advocate. I realize the 3800 is no longer being produced and there are some new engines GM has developed that make more power without boost than a stock 3800 SC. I think some of these newer V6's would make great engine swap choices for a Fiero. But right now I think the 3800 SC gives you the best bang for the buck vs. ANY other engine out there. Just my opinion…

I would like to hear more about these “inexpensive” mods you can get for the 3500/3900 engines. What's available? Who sells it (is it available from more than one company/person)? Have these parts been tested on a dyno or by several people so we know how well they perform and if they are reliable? I would like to know, personally, as I've had customers approach me asking about having me do some swaps using these newer 60 deg V6 engines (some have inquired about mods to increase power). Please share the info.

-ryan

quote Originally posted by Darth Fiero: The broad torque range is what wins a drag race. That's what the SC on the 3800 gives you and that's what the VVT on the 3900 gives you. Honestly I think it is a waste to get rid of it if your engine already has it. Why not take advantage of that technology? Since I don't know much about the VVT LS engines I can't comment much about your claims that "they perform better without VVT". I will say that the aftermarket (and general community) has proven to be pretty slow in getting up to speed on a lot of new technologies the automakers have developed. And their track record has commonly been to "badmouth" some of these new technologies they don't understand or are unfamiliar with. I'm willing to bet that in the long run, VVT will be seen as having a positive impact on performance as more people (and aftermarket companies) come to understand how the system works and how to exploit it to make the most power possible. I bet the same kind of negative stuff has been said about direct injection at some point too. I know it was said about EFI back in the 80’s, and look what we’re doing with it today… The common non-direct injected 3.6 DOHC VVT engines produce about 250hp and 250tq. I wouldn't say that puts a 3800 SC to shame. The direct injected version produces 304hp and 273tq which is impressive, but there's a problem. There is NO aftermarket tuning support currently available for the ECMs that control this engine, at least none that I am aware of. Without it, you can forget about swapping one of these engines into a Fiero unless you are prepared to swap a whole lot of other electronics from the donor car in when you do the swap. This isn't going to make the swap easy (or cheap if you are paying someone else to do it). I HOPE support for these systems does come out soon and I hope it can disable VATS (and/or the need to have the BCM or any other modules present for the engine to run right). Besides that, how many of these DI engines do you see available in salvage vehicles and how much it would cost to get a hold of one? I'm not trying to bust your chops here. I'm simply playing devil's advocate. I realize the 3800 is no longer being produced and there are some new engines GM has developed that make more power without boost than a stock 3800 SC. I think some of these newer V6's would make great engine swap choices for a Fiero. But right now I think the 3800 SC gives you the best bang for the buck vs. ANY other engine out there. Just my opinion… I would like to hear more about these “inexpensive” mods you can get for the 3500/3900 engines. What's available? Who sells it (is it available from more than one company/person)? Have these parts been tested on a dyno or by several people so we know how well they perform and if they are reliable? I would like to know, personally, as I've had customers approach me asking about having me do some swaps using these newer 60 deg V6 engines (some have inquired about mods to increase power). Please share the info. -ryan

The VVT on the 3900 likely doesn't offer as much for the torque range as one would like to think, simply because of fixed cam lobe separation in this app, myself and Joshua have already proven what was speculated in advance elsewhere, that the 3900 cam has more advance and retard range than what is useful. That's why I mentioned the benefits it offers towards emissions, it is the reason the EGR valve could be eliminated. Dual cam VVT is where the most significant benefit is such as in the 3.6L which has a non direct injected 270 hp version.

The VVT 3500 produces 16hp more than the non VVT 3500, is that because of the VVT, or the 3900 heads and intake system it has over the non VVT motor. I'm sure it's a combination of both. Torque is very important but you still need a sufficient amount of hp also otherwise we'd be loosing to diesels.

I've mentioned it before but here it goes again, WOT-Tech on the 60 degree forum offers performance parts for these engines, mainly the 3500 and below at this point. CNCguy also on that forum offers parts to.

Tuning is part of the swap with any modified engine even if you swap the OE PCM with it so lets not beat that "horse". The potential to make excellent power without spending the kind of money non aluminum head engine owners seem to be aledging is there. The power to weight ratio for the engine is an advantage in itself, the aluminum heads weigh right at half of what the iron 2.8L heads do and I imagine there's an even greater over all weight savings relative to the 3800.

You can swap the 3500 with a PCM used to control the 3400. The 3500 top end is a popular upgrade for the 3400. It all just boils down to the trend of "doing what you know" on this forum, otherwise from a number stand point the naturally aspirated aluminum head motors are a better choice for performance. Less weight and more power per litre in the conservative ranges many operate in here.

I purchased a new Northstar throttlebody (other choices available) and adaptor plate, had a 7x trigger ring made and had the stock camshaft reground. The 3 required parts for the swap cost me ~$150, the camshaft regrind was optional but cost ~$85. I decided to make headers, flanges $50. That's it aside from the 730 ecm swap. I've had tuning software and hardware since the forum was new. I forgot about the bypass pressure regulator to convert to a returnless fuel system, depends on your approach, $100 for me, and a must on the 3900, you can use the 3400 rail on the 3500.

VVT is a treat, not a necessity, loosing it doesn't suddenly make an engine a slug. It also doesn't severely reduce its power, just the versatility of it like in the 3800, it becomes a happy medium.

[This message has been edited by Joseph Upson (edited 02-07-2011).]

quote Originally posted by L67: That would certainly be interesting to see. I checked car-part.com and couldn't find a 3900 for less than $700, very likely because its so new. I can buy series II 3800's for $150.00 (with warranty) all day long.

i would love to find a 3800scII for that.

quote Originally posted by Darth Fiero: Without it, you can forget about swapping one of these engines into a Fiero unless you are prepared to swap a whole lot of other electronics from the donor car in when you do the swap. This isn't going to make the swap easy (or cheap if you are paying someone else to do it).

Whats wrong with a bit of extra wires being terminated? Its not that bad. I wont say its easy but there’s a Michaels manual that has all the pin outs and other fun stuff. And for the price, I in about 5000 including the price of the fiero (1500) and all thats left is the upper mount and terminating the bcm.
Matt

Time will tell with these new motors. There is just no way people will give up trying to make the most out of the new technology especially in 10 years when this "new" tech is "old" tech. Like Darth said, EFI wasn't looked kindly on when people could do so much with Carbs easier and cheaper, and look at it now. Most people like to stick with the easier route (especially when on a budget) because they don't have to worry as much about their idea not working and wasting all that time and money trying to make it work. It's still too early to say which engine is "better" but if the technology keeps getting better, more people will flock to it and we'll get some good data.

It's good dialogue and there's reasonable opposition or doubt as the newer motors still have to earn their keep. I looked at the specs for the 04 GTP, 06 GXP V8 and 06 G6 GTP coup, the G6 is faster than the GTP in the quarter convincingly if the data is dependable, yet both cars weight within 100 lbs of eachother, G6 14.2 vs. GTP 14.9s, the GXP, 14.1s but it's about 200 lbs heavier.

I almost withdrew my comment about the VVT probably not making a very large difference in broadening the torque curve, but then I looked at the torque curve for the non VVT 3500 and in the 06 G6 it reaches its 222 lb/ft 600 rpm sooner than the 3800 reaches its 230 lb/ft, but on the hp end reaches 200 hp 400 rpm later. That combination especially having a little more breath up top would probably end up with matching quarter mile times with those two platforms, I didn't find the specs for them.

The VVT definately makes a difference but the catch is this, from what I've observed in simulations, the higher the static compression, the less significant advancing the camshaft becomes. So, eliminate VVT and bump your compression up to gain over the entire torque and power band with a fixed camshaft.

My wife had an 06 Malibu SS sedan with the 3.9. It was a lot of fun to drive, and the 3.9 moved the Malibu around really well. In a Fiero, I imagine it would be lots of fun.

What would be involved installing this engine with the VVT active? I know they also came in the G6 with the 6-speed manual. Has anyone installed this combo in a Fiero?