Originally posted by zkhennings: You want to shift at peak HP. Also my car is not stock and has a bigger cam and everything is ported, and custom exhaust. I run out of air at like 5500 rpms now so I shift around 5000 generally. I only went to 6100 ish for 0 - 60 because the shift from second to third looses a lot of time.
Do you have a dyno chart of that? Even with the bigger cam and porting, the 2.8 still falls flat under 5000. Especially with the stock intake. Shifting anywhere from 4000-4500 will give you faster acceleration, on a 2.8/3.1/3.4.
Originally posted by dematrix86gt: Thats some interesting reading, if im wrong im wrong , their saying gearing along with TQ and HP decides the outcome. interesting!
Gearing and torque curve is what wins races. Along with being able to drive the car correctly. Torque is a direct measurement of power. HP is simply a factor of torque and RPM. More torque means being able to overcome the restrictions of moving the car through the air, and on the ground, faster, thus getting the engine to spin faster, more quickly. And the speed at which your car is moving is a factor of gear ratio and engine RPM.
Even with the bigger cam and porting, the 2.8 still falls flat under 5000. Especially with the stock intake. Shifting anywhere from 4000-4500 will give you faster acceleration, on a 2.8/3.1/3.4.
That is because they have lousy heads that just can't flow. A 3800 has a much better desing for the heads and should pull to over 6,000 with a nice cam. If you really need 350 HP out of a 3800 add two more cylinders. Larry
Do you have a dyno chart of that? Even with the bigger cam and porting, the 2.8 still falls flat under 5000. Especially with the stock intake. Shifting anywhere from 4000-4500 will give you faster acceleration, on a 2.8/3.1/3.4.
No I do not, it is just butt dyno and it is pretty obvious where the engine runs out of air, before I did all the work it fell on it's face wayyyyy earlier. I ported the intake a lot though, I opened up the lower intake a lot especially where the injector bosses are. I am going to do the dawg mod to the upper intake manifold or something similar but more intense, and I will be getting my car dynoed sometime this year, it needs a good tune it leans out a lot when it is cold out
That is because they have lousy heads that just can't flow. A 3800 has a much better desing for the heads and should pull to over 6,000 with a nice cam. If you really need 350 HP out of a 3800 add two more cylinders. Larry
I agree the heads can't flow, but the stock intake is what limits the power first and the cam really decides where the engine wants to make peak power.
You are right, where the engien makes power and how it acts has a lot more to do with the performance of a car than just HP and Torque numbers would suggest. You can compensate for poor head flow by having a smaller LSA with a lot of overlap. I always thougth that the engine in a Fiero was really more suited to a tractor than a sports car. Larry
I would agree, it is a tractor engine. Probably really good in the little S-10 Pickups. They put it in a Fiero because it fit and didn't threaten the Vet. Larry
I don't think it is trash, it is just old technology. I agree trying to get high hp numbers out of it takes a lot of modifications and costs more than what you gain, but back in the day the v6 fiero's were quick at that point in time.
I think the duke is a bad engine, but the 2.8 is definitely not the worst. Sounds good too. HP per liter is also pretty similar to the v8s of the time. It is just old and simple and therefore nothing impressive.
Has been discussed a million times on here, but anyway:
Cam and springs, underdrive pulleys, port/polish heads and blower, intercooler, good exhaust, and a proper tune.
Not to be a weenie, but just about every Fiero mod has been discussed several times before on this board. If we did not re-hash things, the board would be very quiet.
------------------ 84 NB, 3800SC, E-85, VS Cam, 3.0 Pulley, 4T65E-HD, HP Tuners, AEM Wideband, Regal GS Gauges, S-10 Brake Booster. 1/4 mile -12.05 at 111.7mph
I guess my title by this point is very misleading...
Are there any arguments you guys can convince me to install a 3800 (within the next year and a half) instead of turbo the 2.8 even though I just built it and spent so much time on it?
Because the 2.8 likes to spin rod bearings. Very common even at stock HP levels...
Originally posted by DimeMachine: Not to be a weenie, but just about every Fiero mod has been discussed several times before on this board. If we did not re-hash things, the board would be very quiet.
And the reason search exists, isn't so people can ask someone else to find the info for them. Sure old topics may come up again after a while, but 3800 swaps are constantly happening and in-progress. Reading through any number of those should give one a pretty good idea of what needs to be done, to get more power out of a 3800.
And besides, I answered the question anyway. But I wanted to make it known that the information has already been hashed out as well. Re-hashing the same stuff over and over, only to get the same results, is insanity (literally, it is the definition).
And the reason search exists, isn't so people can ask someone else to find the info for them. Sure old topics may come up again after a while, but 3800 swaps are constantly happening and in-progress. Reading through any number of those should give one a pretty good idea of what needs to be done, to get more power out of a 3800.
And besides, I answered the question anyway. But I wanted to make it known that the information has already been hashed out as well. Re-hashing the same stuff over and over, only to get the same results, is insanity (literally, it is the definition).
And the reason search exists, isn't so people can ask someone else to find the info for them. Sure old topics may come up again after a while, but 3800 swaps are constantly happening and in-progress. Reading through any number of those should give one a pretty good idea of what needs to be done, to get more power out of a 3800.
And besides, I answered the question anyway. But I wanted to make it known that the information has already been hashed out as well. Re-hashing the same stuff over and over, only to get the same results, is insanity (literally, it is the definition).
I have done plenty of research. I knew everything that you told me to do. I do have a pretty good idea of what needs to be done. I want a better idea now that I have done the research. Not only have I read through at least 20 3800 swaps on pennocks, but I also have been on the gtp forums as well. I am well versed in how to get more horsepower out of an engine, but that does not mean I know everything. When you ask a specific question you can get more specific information. Also the search function only does so much because you can only search titles. Completely unrelated threads title wise could have the information I need and I will never find it.
Also I wanted this thread for more than just asking that question, I wanted to talk options about which route I should take also with people who have probably done both of the things I was considering. There are some pro 3800 guys and some pro 2.8 turbo guys, and some that have done it all. I am looking for those little specifics that you don't get in the generic threads on similar information. Maybe you haven't realized but there are a lot of misconceptions about things on the forum, and people will answer a question how they have seen it answered and sometimes the information being spread is wrong. It is nice to have a thread where you can clarify things. Also by making the tile only 3800 related but asking questions about a 2.8 turbo I hoped to get answers from people who may have been like me and wanted to turbo the 2.8 and go 3800 but were unsure of which to do, went turbo 2.8 first and decided it was not worth it and went 3800. I wanted to hear why they did that.
Also, maybe somebody had a bad experience trying to get hp that high out of a supercharger, too much expense vs performance. I wanted to know if a turbo can produce an equally smooth powerband on this engine. Just because my title can only be so long does not mean that was all I was looking for. Usually people on this forum pushing around 350 hp are running a turbo. I have seen people get up to around 300 hp with the supercharger. I was wondering why they usually don't go higher. Is it an exponential growth of cost vs hp and past around 300 cost shoots up? I don't think I have run across a 350 hp supercharged 3800 besides maybe the one in that awesome yellow gt bmwguru is working on with the true dual exhaust. And that was a crazy expensive build. Most people do a few mods and throw their 3800 in, and don't dyno it or anything. Usually all the 3800 turbo engines get dynoed so it is easy to see which mods give them that horsepower.
I have made decisions before based solely on the research, and sometimes you miss information no matter how much research you do. Sometimes you have to ask the questions you want to ask. Perfect example when I upgraded my brakes. There are tons of threads where people are all "make sure you use the full size blazer MC." It was not until after I had bought all the parts for my swap and then made a thread discussing brake pads that had not been yet discussed on the forum where I laid out what I bought that someone told me that they themselves found the full size blazer MC too big, and instead used the S10 one which worked great. So now my brake pedal is too stiff and all the research I did indicated that people believed the S10 MC the same size as the fiero one and there would be too much pedal travel. Now I know this is not true and that most people are just wrong.
But I have read tons of 3800 swaps, so many that off the top of my head I could give a list of everything you need to do when swapping a 3800 besides specifics in the wiring harness.
Honestly these threads need tags. I usually use Google to search pennocks because it works way better than the search function because a lot of people name their threads very poorly. Also many threads go in different directions from what they started as but the title does not reflect that. As I said, tags would be very helpful to everyone.
[This message has been edited by zkhennings (edited 07-25-2013).]
I don't think I have run across a 350 hp supercharged 3800 besides maybe the one in that awesome yellow gt bmwguru is working on with the true dual exhaust. And that was a crazy expensive build. Most people do a few mods and throw their 3800 in, and don't dyno it or anything. Usually all the 3800 turbo engines get dynoed so it is easy to see which mods give them that horsepower.
I think you have me confused. I am not currently building any Fieros other than my own....and they don't have true dual exhaust. As for achieving over 350whp....it isn't that hard with a supercharger. It is easier with a turbo, and a turbo can definitely up the ante, but we have 3 supercharged Fieros that we built that are in the 350-400whp range....all manual transmissions and all have used zzp short blocks, heads, cams, intercoolers and custom headers....plus all the usual mods.
I think you have me confused. I am not currently building any Fieros other than my own....and they don't have true dual exhaust. As for achieving over 350whp....it isn't that hard with a supercharger. It is easier with a turbo, and a turbo can definitely up the ante, but we have 3 supercharged Fieros that we built that are in the 350-400whp range....all manual transmissions and all have used zzp short blocks, heads, cams, intercoolers and custom headers....plus all the usual mods.
Dave
350whp isn't that hard out of a 3800 with S/C? What mods did you do that you were able to accomplish that? It's alot of work and typically requires aftermarket heads or head work to accomplish that, not worth it IMO when someone can go turbo stay on stock heads and accomplish the same for much less. OP, for reference here's the clubgp link for the HP cam chart. http://www.clubgp.com/newfo...&p=1&tmode=1&smode=1
[This message has been edited by Slow6 (edited 07-27-2013).]
350whp isn't that hard out of a 3800 with S/C? What mods did you do that you were able to accomplish that? It's alot of work and typically requires aftermarket heads or head work to accomplish that, not worth it IMO when someone can go turbo stay on stock heads and accomplish the same for much less. OP, for reference here's the clubgp link for the HP cam chart. http://www.clubgp.com/newfo...&p=1&tmode=1&smode=1
My Gold GT:
Northstar throttle body 1.84 roller rockers 105lb valve springs Gen V blower with 3.0 pulley 42lb injectors Custom made headers (we make them) Methanol Injection Short Stack intercooler Spec stage 3+ clutch
330whp
Sabooo's GT: Northstar throttle body ported Gen III blower with 3.0 pulley 42lb injectors 105lb springs full size intercooler XP hot cam (or very similar cam) ported and polished cylinder heads custom headers Spec Stage 3 clutch
Made 365whp
Ryan's GT:
Northstar throttle body ported Gen III blower with 2.8 pulley 42lb injectors short stack intercooler with oversize heat exchanger 130lb springs XP hot cam ported and polished cylinder heads custom headers Spec Stage 3 clutch
made just under 400whp
Charlie's car:
Northstar throttle body ported Gen V blower with 2.9 pulley 42lb injectors full size intercooler XPZ cam ZZP stage 3 ported and polished cylinder heads custom headers Spec Stage 3+ clutch and aluminum flywheel methanol injection
estimated 400whp.
I've also noticed that 3800's are not consistent. You can take two identical setups and have a 20% power difference.
Dave
[This message has been edited by bmwguru (edited 07-27-2013).]
Why not do a N/A 3800 swap (they are 1/3 the price of a S/C engine) and then do a mid size turbo later if you want more power. the N/A 3800 is still a solid 200hp motor in a fiero and will last far longer than any 2.8, would be totally competent on a road course and with an very street able turbo 350WHP would be a non issue. Just a thought.
I've also noticed that 3800's are not consistent. You can take two identical setups and have a 20% power difference.
The real world does not find this to be true. Its uncommon to get much of a difference.. air is air, power is power, your different cams and random bs are not going to change anything but powerband and possibly produce some different peak numbers. Your sample size is also extremely small, and your experience with them is also limited compared to people that have been working on them for the last 10 years.
quote
That 870hp turbo, that's not on the v6 is it?
Yes. The reliable power handling of a stock 3800 from heads to oil pan is well above 800cHP.
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350whp isn't that hard out of a 3800 with S/C? What mods did you do that you were able to accomplish that?
Yeah, its REALLY easy when you pull 150lbs out of the transmission... Swapping to a manual will give you some extremely awesome dyno numbers due to the minimal amount of moving parts. On a basic setup 3.4 pulley setup we constantly saw 45-55whp differences between the manual cars and automatics. Example, more than a few guys have made in the 300-315whp range with no appreciable mods aside from nice exhaust and intake when hooked to a 74lb manual transmission and flywheel.
I was working for pontiac back in 1995.....then got turned on to German cars and didn't look back.....except I always kept a Fiero. I'd say I have 20 professional years (being paid on the books) working on cars....everyday. Sorry, I wont drive an automatic and won't build another even though it will hold the power....it isn't for me So, you are saying that camshafts don't make power and they only increase the powerband? I read on the other thread how Darth pwned you on the CASE learn that you say isn't necessary. I was going to comment in that thread, but you don't accept when others tell you how it actually is. My car was misfiring under load which turned out to be a simple CASE learn (years ago.) Camshafts increase the horsepower and torque an engine can make. If you would like I can explain it for you or send you a link to wikipedia. Dave
[This message has been edited by bmwguru (edited 07-28-2013).]
Thought I would bring this back from the dead for kicks.
My Fiero's 2.8 made max HP up to 6000 rpms, so my shifting locations and butt dyno were spot on. Made 132hp to the wheels which was pretty fun.
I was able to sell that 2.8 for $1500 so no worries about my time being wasted and I made a good profit for my labor.
Fiero has sat idle for some time (2 years) as I have been building my WRX in stages, but it is finally approaching finished (as in I should be able to leave it together to do any future work on it) and I have time and money to spend on the Fiero. I have fluid filmed it religiously and washed it regularly as well, and it is really insane how clean everything has stayed. It lives under a water proof but breathable car cover in the driveway.
Working full time as a mechanical engineer for the past three years I have some funds now, with the WRX done I have some time.
For the longest time I was obsessed with doing a full racecar build with cage and suspension including custom subframes, with an ecotec to keep the rear light. This would be really cool but it was hubris and made a goal so lofty from the starting point and also factoring in my situation (at home with parents at 25 because of college debt) it resulted in nothing but the Fiero sitting stagnant for a long time.
So I've changed my mind. I want to keep it simple, I want to keep it inexpensive, I want cheap power. If I want to do a full racecar build I will start with a Miata.
So back to 3800 it is, and I will keep it supercharged for now. Smaller pulley, a cam, springs, port the supercharger and the associated mods to go along with that are all I will do to it for now as well as the standard little stuff. I know it will be really fun and I am going to attempt to have the simplest engine bay possible.
Found a series two L67 nearby for $399 with only 80,000 miles on it, and I should be picking it up in the next few weeks.
