This is an effort to get those willing to do an engine swop to another V6 to come out of the iron ages and loose those stoneage heads. I stumbled across a good deal on a couple of 3500s some months back and felt it would be backwards to bolt 2.8L parts on it. The engine is rated at 201 hp and 220 lb/ft and is from an 05 G6. It has a steel crank with larger crank pins than previous 60 degree engines, 5.9" rods and an oil squirter on pistons #5 and 6. The coolant return is located at the back end of the intake manifold so the old coolant pipe that transverses the engine diagonally will be eliminated. I hope to have it completed within the next 2 months which leaves the possibility it maybe replaced with the 3900. It will be intercooled however the location of the intercooler will be a surprise left to view when it is completed.
I have already installed a roller cam with turbo specs: Duration: 266 int 264exh lift: .468 .454 Lobe sep: 114 ~2500 - 6500 rpm
The ride home
Today, the patch on the front reads ROUSH, I know what they do but don't know if they had any performance input on this engine. The other 3500 didn't have it and the salvager I purchased it from looked at it and felt he should charge me more because of the implication. It probably doesn't mean a thing other than they are making some of the GMs stock parts for it, unless there is a special order code it is associated with.
Exhaust manifolds are efficient and perfect for the project, I would choose efficient cast iron manifolds in a turbo application over headers any day for durability and because the OE stainless headers from other GM cars/trucks I am using for my heavy gauge stainless mandrel bend source still cracked under naturally aspirated conditions and I don't want to have to deal with that kind of madness.
They exit in the right location for clearance, the forward manifold turning down and the aft straight out the back.
Ignore the turbo in the picture, I'm using the engine to complete a replacement setup to use temporarily on the 3100 in the car.
[This message has been edited by Joseph Upson (edited 10-18-2006).]
Fit has already been verified, this is one picture of 48 that were taken with measurements, the turbos will be positioned in the same proximity to the engine on the stand and the plumming welded into place. The turbos are T3s with .60 compressor wheels and .48 turbine housings. I have .63 turbine housings if the cam and the higher flowing heads and intake relative to the 3400 indicate there is more power to be had by doing so. The compressor size is 74% efficient at 10psi and 70% at 15 psi at 3.5L displacement around 6500 rpm.
I found threaded nipples at Advance autoparts for the oil return, they turned out to be perfect for the job, after drilling a 5/8" hole I was able to screw them firmly into the aluminum pan.
The throttle body is ~66 mm compared to the 3400 TB ~ 56 mm so it will definately not be a hindrance when the ventilators (turbos) are working at wide open throttle, The upper intake does not appear to have runners internally so that should also be a plus for flow. I will go over the process of converting the electric throttle body to manual function once it's completed, I have already started on it.
Here is the link to an earlier thread addressing the 7x reluctor ring project to replace the new design that will not work with the earlier ECMs, there is currently an external 7x trigger system available on the 660 site. https://www.fiero.nl/forum/Forum2/HTML/073962.html#lastpost
[This message has been edited by Joseph Upson (edited 10-19-2006).]
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10:54 PM
tuner2m6t Member
Posts: 406 From: Adrian, Michigan USA Registered: Nov 2005
This looks really cool. Keep us updated on pics and progress. Are you going to be using the g6 tranny?
Haven't got my hands on one yet and currently plan to install a 5 spd from a 92 Beretta. My preference is to get the 3900 first and do the 6 spd last or at the same time. I believe the 3900 under boost will make lots of power very likely well over 400 with a cam because it has a higher flowing intake and heads with 1.8/1.5 valves. It's 40 hp more than the 3500 but that's naturally aspirated, boosted characteristics would be much different I believe.
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11:33 PM
Scott-Wa Member
Posts: 5392 From: Tacoma, WA, USA Registered: Mar 2002
How does this swap compare to other swaps? The only 2 swaps I have first hand experience with are a 3.2 and a 350. So better yet how does a 3500/3900 swap compare to these 2? Does it bolt up on an 85-87 or 88 cradle? 3.65 4spd tranny bolt up? Any cable interferences?
How does this swap compare to other swaps? The only 2 swaps I have first hand experience with are a 3.2 and a 350. So better yet how does a 3500/3900 swap compare to these 2? Does it bolt up on an 85-87 or 88 cradle? 3.65 4spd tranny bolt up? Any cable interferences?
Bolts to the same transmissions the 2.8 bolts to, haven't seen the bolt hole that was moved on the right side of the 3900 I believe but the 3500 needs a little notch in the oil pan to clear the front engine bracket and of course an attachment point for the dog bone will be needed and a notch in the decklid rail to clear the alternator if it is not moved from above the valve cover. It's pretty much a drop in with the needed accomodations for the different parts, throttle body linkage etc.
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12:06 AM
AutoTech Member
Posts: 2385 From: St. Charles, Illinois Registered: Aug 2004
Why did you decide on twin turbos instead of a properly sized single? Anything more than liking to say "twin turbos baby!" ?
Wondering if your expecting better response or they just happen to add up to an optimumn size.
My plans for the motor and potential upgrades as well as what I have available and yes the twin turbo title as well as the ability to increase output without having to change the turbo and the efficiency range that they will operate in.
The range of my cam and engine displacement calls for at least two T3s with .48 turbines, I would have to shell out several hundred dollars if not more to purchase a single larger turbo which might pose space problems concerning where I would like to place it and where I don't want to place it and that might cause an increase in spool up time above what the two T3s would. The relatively large exhaust flow area allows for a more aggressive cam in terms of overlap because the back pressure will be low until boost pressures get considerably high which will make the engine more effective at higher rpm and fuel efficient at lower rpm with little back pressure during cruise mode.
[This message has been edited by Joseph Upson (edited 10-19-2006).]
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11:23 AM
ryan.hess Member
Posts: 20784 From: Orlando, FL Registered: Dec 2002
why do only 5+6 have oil squirters? Any plans on giving them all oil?
My best guess from what I have read here and there is that cylinder #5 and 6 are the ones under the most stress from the 3400 history with them, due to higher temperatures. I will address the remaining four pistons that do not have an oil squirter by relpacing the whole engine with a 3900 that does have them on all six, possibly before the 3500 is ever installed.
What kind of cars and years do the 3900's come from? Are the cams and upgade parts easy to come by?
05 and up Impala, Malibu Maxx, G6 and Monte Carlo, and a couple or so mini vans. The 3900 is an engine all it's own along with the matching VVT 3500 which sports the same platform with a smaller bore, unlike the non VVT 3500 I have, it looks like the typical small V6 on the outside for the most part but that's where it ends, bigger valves, repositioned combustion chambers, repositioned cylinders, etc. I know of no such upgrades available for either of the three engines except after market vavle springs. I had the stock roller cam reground to turbo specs. The 3900 has a cam unique for the VVT system as well as larger journals.
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12:14 PM
ryan.hess Member
Posts: 20784 From: Orlando, FL Registered: Dec 2002
The VVT system can't be left disconnected... I think if you do, the cam sprockets freewheel and you bend valves.
I thought about that but then given the high probability of an electronics failure that would be a bad design and very likely why the 3900 unlike the others has valve reliefs in the pistons so it's highly unlikely that the VVT would damage in the same manner that a timing chain failure would. The cam has to have clearance for its full range of retard and advance from the start since it varies so I believe it is highly unlikely that that would be the case. Its range is probably limited so that that does not happen especially since something as simple as leaving it unplugged and cranking the engine after maintenance could ruin it. Just remembered, it doesn't freewheel according CNCGuy who has one, it has a limited range of about 5 mm in either direction.
[This message has been edited by Joseph Upson (edited 10-19-2006).]
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12:46 PM
ryan.hess Member
Posts: 20784 From: Orlando, FL Registered: Dec 2002
Originally posted by Joseph Upson: I thought about that but then given the high probability of an electronics failure that would be a bad design and very likely why the 3900 unlike the others has valve reliefs in the pistons so it's highly unlikely that the VVT would damage in the same manner that a timing chain failure would. The cam has to have clearance for its full range of retard and advance from the start since it varies so I believe it is highly unlikely that that would be the case. Its range is probably limited so that that does not happen especially since something as simple as leaving it unplugged and cranking the engine after maintenance could ruin it. Just remembered, it doesn't freewheel according CNCGuy who has one, it has a limited range of about 5 mm in either direction.
Hmm... maybe it's a different design from the northstar ones. I was told that there were no "limits" on the phaser, and because of that you couldn't just unplug them. Does CNCguy post here? Or should I start a thread on 60v6?
I would like some hard facts on the system.
[This message has been edited by ryan.hess (edited 10-19-2006).]
CNCGuy is on the 660 site, do a search for the latest on the 3900, I forgot which forum it was under. The big difference between the Northstar and the 3900 VVT is the 3900 does not have the ability to change the angle between the exhaust and intake lobes. I would be very surprised if it were an interference engine in the wake of a VVT failure or disconnect.
Fiero sits low enough so that all that's needed is a step formation of bricks or boards and padding for the door jam to rotate it up and into place although the second engine was inserted with a fork lift. Moving it out of the car was easy using the step method.
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09:07 PM
Oct 20th, 2006
floridafiero Member
Posts: 377 From: Cocoa Beach, Florida Registered: Jun 2004
Looks great! I love the pic with the motor in the car.
The salvager tells me $300 for an 05 3500 from a G6 with 7k on it, I thought he was crazy, and that I was crazy for wasting that kind of time thinking about it. I got home and took the seat out of the car as quick as I could thinking it might not be there by the time I got back. They have more appropriate prices on them now.
Performed a compression test today; 05 3500 7k miles on it. I thought I bent a valve turning the crank by hand while the cam sprocket was disconnected after forgetting it was an interference engine and hitting one of the valves. The compression results frightened me at first:
Then some individuals on the 60 degree sight indicated it's not likely I could do it with my hand and that because the engine is very low mileage, has been sitting for a while and the pressure is steadily increasing in the two lowest cylinders that the rings haven't seated yet. So now I'm not as stressed. I performed the test using WD40 as a precaustionary measure because I didn't know how long the engine had been on the shelf and didn't want to spin it over dry with the starter.
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05:50 PM
Dec 18th, 2006
faytmorgan Member
Posts: 99 From: anoka, mn usa Registered: Nov 2006
I made a trip home for a short break and was able to make some progress. Unfortunately twice in a row I procrastinated as well as worked on some surprise problems before actually getting started. Although this started as a 3500 thread in the end it will almost certainly be a Twin turbo 3900, I'm just doing the mock up with the 3500 since I already have it on the stand.
I did get the turbos mounted up before I left, I had two things in mind; ease of removal and ease of upgrade to something larger as if that will be necessary, although 7000 rpm, 12 psi and the cam grind I intend to run would warrant the larger .63 turbine housings instead of the .48. I used 16 gauge 2" 304 stainless from the manifold to the turbo for corrosion and heat resistance, I will install heat shielding around that particular tubing as opposed to wrapping it to help control the heat. If I can get some assurance that wrapping the stainless will not be problematic serving 3 cylinders under moderate abuse I will do that instead. I am using 2.25" mild steel tubing for the exhaust outlet and will ceramic paint and heat wrap it from the turbo back some distance away from the forward firewall.
On my next trip home I hope to finish and install it but if not, at least complete the exhaust, intercooler plumbing and install the wastegates.
While walking in the back yard I stumbled across some nature in the middle of a spring fling, I wish I had a video camera which I intend to get soon. I could have recorded the mating dance thingy they do when they coil around each other repetitively. They're not poisonous but anyone with any experience with black racers know they're mean as hell and if you pick one up he'll bite repetitively and to my knowledge they don't tame down.
Ooops, I forgot to change the pixel size back, so the picture of both snakes together is to large, here is one peaking out from under the shed after I disturbed him on the other side, within minutes after I left they were back out in the cool sunlight going at it for hours literally.
[This message has been edited by Joseph Upson (edited 04-16-2007).]
Thought I would post this composition of engine stand dyno pulls to keep the thread alive until I can get back home hopefully in the next 2 months and try to finish the setup on the stand so that all that is left to do is buy a 3900 to go in place of the 3500. I wish there was an example of American muscle like this.
Very unique swap. One properly sized turbo would probably generate the same total Horsepower but the low end with two smaller turbos might be slightly better. In a Fiero engine compartment you don't have much room for plumbing so measure right and build once. I'm sure that many of us here are waiting to see how this engine will perform. Since you could have saved hours of work by just bolting up a 3800SC, why did you not consider this engine? Good luck with the swap. Whatever the outcome the performance should be way ahead of the 2.8L. Once you experience the power than a boosted engine can make it's hard driving a Fiero without one.
Here is the adaptor plate used to mount a manual linkage Northstar or 5.3L throttlebody to the 3900 next to a Northstar throttlebody and LS6 valve springs which are much stronger and can handle more lift than the stock ~230 lb springs. They also fit the 3500 and 3900 heads without any modifications to the seat or valve stem seal. There is also an adaptor plate available to bolt the manual link 3400 throttlebody or a high flow billet throttlebody to the 3500, and there is a second design external crank sensor kit about to be released to help facilitate use of the earlier ECMs and PCMs that use a 7x crank signal for use on the 3500 and 3900.
I purchased a Stamp Works kit to help me recall and learn how to program the micro chips to read voltages (sensors), send voltage pulses, operate motors, display data on an LCD screen and most important, draw up a circuit for a pulse generator that will read engine rpm and oil pressure and then pulse the Variable Valve timing module that uses 2 wires so that the cam retards at a gradual rate linearly with rpm just for starters. I can write a program to perform the task based on several other parameters as well like TPS position since it can be programmed to read voltage. It is capable of doing many, many more functions than what I have stated including data logging and to get an idea of the depth of support it has there is a GPS module available for programming into the loop, and EGT sensor module, and for those who are familiar with the show, this is the equipment that was used to make the robots for the robot wars competition on the Discover channel.
Here is the main board about 8"x6" which plugs into my PC for programming whatever project I'm working on, I have the accessories it came with such as the LCD screen which I'm eager to learn how to program and eventually make a stand alone functioning unit for like what comes with some engine management equipment to take the place of a laptop in the car to view stats.
[This message has been edited by Joseph Upson (edited 05-15-2007).]
Nice project. Which ECM will you use with the 3900? And how are you going to handle the VVT and DOD and electronic throttle?
730/727 ECM, VVT can be run as on and off at a certain rpm, or for more traditional performance the engine can be converted to non VVT by fixing the modulator at the most optimum cam angle by blocking movement of the vanes on the stock cam or swopping it out with a resized journal earlier cam and timing parts. DOD is only available on a few select 07 vehicles, the Impala is the only one I'm aware of and it is also an on off type of function since the engine is naturally balanced shutting down one bank of cylinders unlike the 5.3L. Someone mentioned the V8 being a smoother running engine than the V6 comparing the 3.8 and balance shafts. I don't know which is however I'm curious as to whether or not the degree of the "V" has anything to do with why the 90 deg 3.8 has used one and the 60 degree series apparently has not.
Very unique swap. One properly sized turbo would probably generate the same total Horsepower but the low end with two smaller turbos might be slightly better. In a Fiero engine compartment you don't have much room for plumbing so measure right and build once. I'm sure that many of us here are waiting to see how this engine will perform. Since you could have saved hours of work by just bolting up a 3800SC, why did you not consider this engine? Good luck with the swap. Whatever the outcome the performance should be way ahead of the 2.8L. Once you experience the power than a boosted engine can make it's hard driving a Fiero without one.
The 3800 SC is all iron and takes up more space and requires more effort to fit than a 60 degree engine that will accept the engine mounts and brackets I already have. I'm using the 6spd transmission and already have the stock flywheel that will not bolt to the 3800. The 3500 and 3900 is more efficient than a naturally aspirated 3800 with only 10 lb/ft difference at peek output between it and the 3500 for 06 down and for the 07 G6 3500: 224hp 220lb/ft, 3900 HO: 270 hp 258 lb/ft plus the steel crank and forged rods and floating pistons for the 3900 and ever important oil squirter for every piston. 7 psi on either of those engines will skyrocket them past the 3800SC. There is already at least one 3500 installed and running on the 60 degree V6 forum, and one of the guys I communicate with about the project on that forum will more than likely beat me to the punch with use of the 3900 seeing that he already has the rejournaled cam to eliminate the VVT.
This was not just a matter of preference for me, when I put these two engines side by side and look at numbers and potential, the aluminum head engines are a better choice by far for what I want, great mileage and fearsome acceleration.
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08:08 PM
PFF
System Bot
May 22nd, 2007
Faster7 Junior Member
Posts: 8 From: Springfield, MO Registered: Oct 2006
Very nice! I've been tossing around the idea of installing a 3.5/3.9, but I think the sweetest setup for me would be to keep the displacement on demand. If they'd mate a DOD V6 to the 6 speed manual so that I could get it all from one donor car..... Surely on the highway 3 cyl operation would net 40+mpg in a fiero?
Very nice! I've been tossing around the idea of installing a 3.5/3.9, but I think the sweetest setup for me would be to keep the displacement on demand. If they'd mate a DOD V6 to the 6 speed manual so that I could get it all from one donor car..... Surely on the highway 3 cyl operation would net 40+mpg in a fiero?
You can probably get that or close to that MPG by using the 730 ECM and activating the engine lean run mode I believe it's called, which was deactivated for production cars, but allows the engine to run at a leaner air/fuel ratio during hwy cruise for added economy and since the 3.9 has oil squirters to cool the pistons you could probably run as high as 16:1 which I have read mention of some engines being tested at, and not have a problem.
The issue with the DOD (known by another term in the V6) is that it apparently is still under testing because it can only be found in one car if I recall correctly; 07 Impala. It also appears to be a rather simple system to operate due to the natural balance state of the engine allowing for one bank of cylinders, injectors and valves to be shut off and some additional tensioning of the accessory belt. It's done in sequence for smoothness so an on off switch should still accomplish the same thing. GM describes an exceptional fuel savings but they don't give a number.
Some 3800 owners here on the forum are well into the 30+ MPG range so I don't see why the 3.9 apparently being a little more efficient can't get a little better MPG, actually any of the aluminum head engines should be able to push toward the upper 30+ MPG limit if you tune for it.
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08:12 AM
Will Member
Posts: 14250 From: Where you least expect me Registered: Jun 2000
Yeah, just rig up a switch and remember that you'll have to push the throttle further to make up for it.
Maybe even a Nitrous type throttle switch could be used to bring the engine out of 3 cyl operation automatically when you nail it.
Why the cynicism Will, 3cyl mode is only intended for constant cruise speed on the hwy and I don't think cruise control will have much of a problem compensating for the drop in power with increased throttle. It's just an idea in its infancy. If it doesn't work there is nothing lost, default is all 6 cylinders firing, if it does however, there is a lot gained. How about something encouraging.
Oh yeah! Happy Memorial Day
[This message has been edited by Joseph Upson (edited 05-28-2007).]
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03:51 PM
May 29th, 2007
Lilchief Member
Posts: 1738 From: Vevay,Indiana Registered: Feb 2004
Joseph: Since you seem to be more familiar with the 3500/3900 engines, I was wondering if you have any head flow numbers for the 3900? I was wanting to compare them to the 3.8SC heads ( don't know their flow numbers either). I'm wondering if a turbo for a 3.8 is compatible with a 3900, particularly the PT61 that cartuning is selling for the 3.8. I'm still mistified on the choice technics for turbos. Well just kicking around this idea. My 3.4 is somewhat disappointing and a 3900 turbo might be the answer. Hope this isn't too far off subject.
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85 GT 3.4 14.9 @ 90 1.9 60' Old TH125/3.06 Unknown New 4T60/3.42
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03:51 AM
Will Member
Posts: 14250 From: Where you least expect me Registered: Jun 2000
Why the cynicism Will, 3cyl mode is only intended for constant cruise speed on the hwy and I don't think cruise control will have much of a problem compensating for the drop in power with increased throttle. It's just an idea in its infancy. If it doesn't work there is nothing lost, default is all 6 cylinders firing, if it does however, there is a lot gained. How about something encouraging.
Oh yeah! Happy Memorial Day
Wasn't cynicism. Think back to the V8/6/4 days of Cadillac... It's just a matter of the level of intrusion you're willing to accept from a fuel saving device... You will probably want to use an electrocruise instead of a vacuum operated cruise control, though.
Joseph: Since you seem to be more familiar with the 3500/3900 engines, I was wondering if you have any head flow numbers for the 3900? I was wanting to compare them to the 3.8SC heads ( don't know their flow numbers either). I'm wondering if a turbo for a 3.8 is compatible with a 3900, particularly the PT61 that cartuning is selling for the 3.8. I'm still mistified on the choice technics for turbos. Well just kicking around this idea. My 3.4 is somewhat disappointing and a 3900 turbo might be the answer. Hope this isn't too far off subject.
I have my 3900 heads with me in the closet and I am hoping to get them to the machine shop soon for flow numbers. A lot of fwd owners are swopping their top ends out for the 3500 because it flows better than the 3400, I don't see any comparison between the 3900 heads and the first design 3500 heads the ports and valves are so much larger and given that the 3900 HO puts down 270 HP vs. the 3800SCs 260 HP I doubt there is much of a comparison there either. The next full work day I get off I will make an effort to get the heads flowed provided the price is a reasonable expenditure. The 3500 heads flow numbers are posted on the 60 degree forum under one of the tech info icons.
Wasn't cynicism. Think back to the V8/6/4 days of Cadillac... It's just a matter of the level of intrusion you're willing to accept from a fuel saving device... You will probably want to use an electrocruise instead of a vacuum operated cruise control, though.
My understanding is that cadillac took an entirely different approach to accomplish this in the 8/4/6 series and that there is little to no comparison between the dyanmics between the two engines given that disabling one bank on a V8 will have an entirely different effect than disabling one bank on a naturally balanced V6.
I intend to pull the fuse for one bank of injectors while on the interstate to see what the effect is with 3 cylinders firing at an evenly spaced 120 degrees apart. Of course it will not be quite the same since the valves will still open on time but it's a start for an idea. Heck if the engine runs smooth enough I might see if I actually save gas. I recall a long time ago having one bank of injectors go out due to the fuse and the engine continued to run. I was astonished upon finding the blown fuse that it ran on three cylinders. I wasn't driving it to note the effect at the time.
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07:01 PM
Lilchief Member
Posts: 1738 From: Vevay,Indiana Registered: Feb 2004
3 cylinder operation would be 240* of crank rotation or 120* cam. My chevy sprint was a 3 cylinder 1L, ran like a top. Just how much will the other 3 cylinders ,non firing, hurt? Interested in how this will turn out.
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85 GT 3.4 14.9 @ 90 1.9 60' Old TH125/3.06 Unknown New 4T60/3.42