Just looking for new info from anyone who has made the switch to a header setup in their 3800 SC fiero what their thoughts are. Before and after dyno or 1/4 mile times would be awesome info to have but I will settle for any info you have to provide. I have been stuck at 11.8 @114MPH for several years and looking for a mod (other than a turbo or N2O) to get about 20-40 more HP.
Thanks in advance.
Dime/Toys
------------------ 84/87 NB, 3800SC, E-85, VS Cam, 2.8 Pulley, 4T65E-HD, HP Tuners, AEM Wideband, Regal GS Gauges, S-10 Brake Booster. 1/4 mile -11.85 at 114mph
I have TOG headers on a 3800 SC Series III engine and am satisfied with them but do not really know if they add 20-30 hp. You should note that I tuned conservatively for reliability instead of absolute max HP. The dyno run showed around 300 HP at the wheels with a Getrag 282 transmission. I suspect that I could get a bit more HP out of this engine with a pulley change and/or tune mod. The current SC pulley is a 3.4" diameter but I have 3.0" in my storage area if I want more boost.
Current engine mods are as follows:
TOG header larger intake and exhaust piping ZZP intercooler ZZP fuel logs Northstar TV 3.4" modular pulley VS cam 85 mm SLP MAF Ceramic coated exhaust
Nelson
[This message has been edited by hnthomps (edited 01-24-2020).]
You may want to make your exhaust modular since your car is a street/track car. Have a set of short (18" inches or more) header extentions to use on the track and when your are done at the track install back the muffled set up. What kind of exhaust do you have? How long is it?
Cooler intake air allows more fuel and more ignition advance. Dont know how many horse it will gain, but it opens the door....
He is already using E85 and that would give him plenty of cooling. What I would do if I had that set up to take advange of the cooling properties of E85, I would install a 7th injector right after the TB. By spraying E85 in the upstrem it can absorb some heat from the incoming air before it gets compressed. At the same time the cooler compressed air has the oxygen molecules packed closer together making the charge denser and even more so that it also carries the extra oxygen and hydrocarbons from the E85 itself. It'll be like water/meth but with a punch. But then again, he has to balance the extra intake volume with more exhaust flow.
Will the full stack immediately result in 20-40 hp, or does it allow for more tuning which results in 20-40 more? Serious question.
Keep the ideas coming - I appreciate them! Since I have E85 and can run 20 degrees timing no problem with a Gen 3 and 2.8, I think the intercooler would become an obstruction due to how small the area is under the supercharger. Think about all the space the intercooler heat exhhanger takes and It quickly makes sense that this would probably cost me HP. If the surface area could be made much larger, then the cooling effect would help. Concur?
He is already using E85 and that would give him plenty of cooling. What I would do if I had that set up to take advange of the cooling properties of E85, I would install a 7th injector right after the TB. By spraying E85 in the upstrem it can absorb some heat from the incoming air before it gets compressed. At the same time the cooler compressed air has the oxygen molecules packed closer together making the charge denser and even more so that it also carries the extra oxygen and hydrocarbons from the E85 itself. It'll be like water/meth but with a punch. But then again, he has to balance the extra intake volume with more exhaust flow.
My biggest concern here would be about E85 getting into the supercharger bearings and dissolving the grease resulting in failure. It has been a while since I had a SC apart so I might be wrong but I don't think I am...
The intercooler will help. Most of your power from the intercooler comes from pullying down though. You could add an intercooler, and a gen V and stay on the 2.8, and you MIGHT get 20hp, but again that sounds like a lot of money for 20hp to me....
My series III I runs 11 lbs of boost with a 3.4" pulley. The engine runs strong but would not run without KR's until I added the SSIC (for deck clearance). That allowed the engine to make the extra power safely. As for headers they should help but I am unconvinced that they will give you more than what a removal of the main restriction will. The main restriction point in the exhaust is the front manifold and the Powerlog eliminates that. Didn't use the GTP headers because you lose a good part of the trunk. IMO, the powerlog may be as effective as the headers will be.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
My biggest concern here would be about E85 getting into the supercharger bearings and dissolving the grease resulting in failure. It has been a while since I had a SC apart so I might be wrong but I don't think I am...
This would fix that problem. I've been using this since switched to E85
This would fix that problem. I've been using this since switched to E85
Interesting. I will have to ponder the 7th injector idea... Not sure how you would manage the AFR as the stock PCM would have no way of managing it.... My initial reaction is it would be easier to just use a nitrous kit as that way you get more oxygen and the cooling affect. I have 2 big concerns about N20. 1. where to get it around the twin cities. Seems like quite a drive. 2. Expensive and short lived. Seems like the way most go though when they run out of M90 ability and dont want to go to a turbo...
[This message has been edited by DimeMachine (edited 01-20-2020).]
Originally posted by DimeMachine: Interesting. I will have to ponder the 7th injector idea... Not sure how you would manage the AFR as the stock PCM would have no way of managing it.... My initial reaction is it would be easier to just use a nitrous kit as that way you get more oxygen and the cooling affect. I have 2 big concerns about N20. 1. where to get it around the twin cities. Seems like quite a drive. 2. Expensive and short lived. Seems like the way most go though when they run out of M90 ability and dont want to go to a turbo...
The M90 is not designed for a wet intake charge. If the engine needs more fuel you can upsize injectors and adjust the MAF table accordingly.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
Just a thought, but would changing the final drive gear ratios in the trans (Chain Gears) up to 3.69 from the stock 2.93 help in the quarter mile time. I know when I switched rear ratios in one of my other cars, it felt like I had added a new engine with 100 more HP. I know it would be quicker off the line, but not sure how the top end might work out for you. This was one of the mods I had planned on my SC3800 before I sold it.
------------------ '87 GT , '00 3800 Series II SC, 4t65e, Vue Power Steering. (SOLD)
The M90 is not designed for a wet intake charge. If the engine needs more fuel you can upsize injectors and adjust the MAF table accordingly.
Don't need any more fuel, The point he was making was since I am on E85, what if one was to inject some of the E85 prior to the blower to help cool the intake charge. My biggest concern was fuel management and blower bearings haveing their grease dissolved. Easier/better to go to Nitrous before doing this.
Just a thought, but would changing the final drive gear ratios in the trans (Chain Gears) up to 3.69 from the stock 2.93 help in the quarter mile time. I know when I switched rear ratios in one of my other cars, it felt like I had added a new engine with 100 more HP. I know it would be quicker off the line, but not sure how the top end might work out for you. This was one of the mods I had planned on my SC3800 before I sold it.
This is a good thought as there is plenty of time spent in third gear in the high 4500 - 4800RPM range and going to lower gears would allow the engine to operate in the low 5000 RPM range during that 3-4 seconds to make more power. I wonder about durability of the tranny and traction with the M.T. ET street tires with lower gears.
Anyone have any first hand b4 and after at the track with 3800 and a gear change?
[This message has been edited by DimeMachine (edited 01-20-2020).]
Porting and full stack intercooler. Let it flow air and cool the incoming charge. Have you pulled vac info from CAI and pressure info on exhaust?
Excellent thoughts. Wish I knew what the M90 porting would be worth on my setup. If E85 was not available, an intercooler would be a no brainier. But since e85 is available and I am NOT spark limited in reaching MBT, then due to the small area under the blower, I believe an intercooler would loose HP due to restricting flow.
I put a port in between my air cleaner and MAF and registered no vacuum at WOT 5000 RPM's so I think my intake setup is sound. I put a pressure gauge in the crossover and I if I recall correctly, came up with 4.5 PSI at 6000 RPM's - which is not bad.
Starting to think all the "easy" hp with the M90 setup has been made. Looking like I might have to dig into N2O a little deeper.
------------------ 84/87 NB, 3800SC, E-85, VS Cam, 2.8 Pulley, 4T65E-HD, HP Tuners, AEM Wideband, Regal GS Gauges, S-10 Brake Booster. 1/4 mile -11.85 at 114mph
[This message has been edited by DimeMachine (edited 01-21-2020).]
The full stack will not restrict flow, the intake tract is under pressure - its forcing more air to the intake valves than the engine can process. Cooling the air charge will allow for more fuel and more boost, and more timing if the setup can handle it. Have you talked to the folks at ZZP about the option?
The full stack will not restrict flow, the intake tract is under pressure - its forcing more air to the intake valves than the engine can process. Cooling the air charge will allow for more fuel and more boost, and more timing if the setup can handle it. Have you talked to the folks at ZZP about the option?
I appreciate the comment. I respectfully disagree with your statement though (given my situation). I am already at 13-14 PSI boost and can run full timing without being knock limited. It seems to me if you occupy a large percentage of the area under the supercharger with the heat IC exhchanger that does have a fair amount of volume, it would probably increase my boost level a couple of pounds due to the extra restriction. This would mean less flow to the heads. If one of us was a fluid design engineer we could probably prove one scenario over the other with an engineering equasion but since I am not, I cannot. The temperature drop would help create a more dense oxygen and fuel mixture - but at the cost of restricted flow. Take a look at how larger intercoolers are for centrifugal superchargers - they are huge. This allows for a large temp drop and no restriction in flow.
Anyone else want to chime in on this. I do not NEED to be right, I very much would like to find the best answer together.
------------------ 84/87 NB, 3800SC, E-85, VS Cam, 2.8 Pulley, 4T65E-HD, HP Tuners, AEM Wideband, Regal GS Gauges, S-10 Brake Booster. 1/4 mile -11.85 at 114mph
I have TOG headers on a 3800 SC Series III engine and am satisfied with them but do not really know if they add 20-30 hp. You should note that I tuned conservatively for reliability instead of absolute max HP. The dyno run showed around 300 HP at the wheels with a Getrag 282 transmission. I suspect that I could get a bit more HP out of this engine with a pulley change and/or tune mod. The current SC pulley is a 3.4" diameter but I have 3.0" in my storage area if I want more boost.
Current engine mods are as follows:
TOG header larger intake and exhaust piping ZZP intercooler ZZP fuel logs Northstar TV 3.4" modular pulley VS cam 85 mm SLP MAF Ceramic coated exhaust
Nelson
Nice looking swap. Have you had the chance to run the 1/4 with it?
Just did, thank you for taking the time to respond - I appreciate it. I will take another look at the intercooler idea - keep in mind that due to the latent heat of vaporization of Ethanol is far superior to gasoline AND you have to use 32% or so more ethanol than gasoline so you are getting a real "liquid intercooling" effect from E85 as well as its 105 octane. There are enough folks running around with an e85 3800 SC Fiero, I really wish someone could chime in on what they gained adding an intercooler at this point. If it was cheap, I would just try it and sell it if it did now materially help. I have no doubt that if I was on regular 92 octane fuel it would help a ton.
Thanks again for sharing your thoughts!!!!!
[This message has been edited by DimeMachine (edited 01-24-2020).]
The VS cam is relatively mild, have you considered the XP or XPZ cam?
I have and if I had it to do over again I would try it as it is a little more aggressive with regards to duration and since the VS is plenty easy to use on the street I am sure the XP would be fine for the street as well.
That having been said, based upon the PFF 1/4 mile list, there does not seem to be a huge difference with just the XP cam...
Would your tires allow you to leave harder? Someone already mentioned the 3.69 gearset change, what about a higher stall torque converter?
Without getting serious there isn't too much more to gain on the SC (think heads + bigger cam like XPZ).
The intercooler and dropping a bit on the pulley might help, but I don't think its a very effective return on investment.
Are you completely adverse to putting a turbo on?
I agree & logic tells me that going to a lower ratio gear would help launch harder and get that long amount of time spent in 3rd gear at a higher RPM. I found an old thread (attached below) and several PFF members chimed in that it wont help much due to the L67 long broad torque curve.
Would your tires allow you to leave harder? Someone already mentioned the 3.69 gearset change, what about a higher stall torque converter?
Without getting serious there isn't too much more to gain on the SC (think heads + bigger cam like XPZ).
The intercooler and dropping a bit on the pulley might help, but I don't think its a very effective return on investment.
Are you completely adverse to putting a turbo on?
More goode thoughts and ideas - much apprediated, keep em coming!!
Three main reasons I don't want to turbo it. 1. Cost, the goal of this car since I built it 8+ years ago has been to go pretty darn fast for low $$$ Thus the name "DimeMachine"... 2. Turbo opens the door to 500+ hp. There used to be a chain available that allowed the 4t65E HD (with other upgrades) to handle this kind of HP. Now I believe that chain is no longer available and so 400WHP is about all the tranny can be build to handle. Kind of a waste to go Turbo if you can only barely get into the turbo's potential. 3. I love the instant torque the M90 gives the 3800 with the stock converter anytime you punch it at the stop light.
How much does it weight with you in it? Lighter weight = acceleration. Look for ways to make it lighter. My Fiero weights 2350+ with me in it and it makes 304WHP and accelerates pretty fast. You should look into making it lighter instead of making it more powerful! Just a thought!
I don't know but have seen people who seem to know state that the gen V supercharger is superior to a ported gen III. If so, they shouldn't be that hard to find since I've got two of them.
Originally posted by DimeMachine: Nice looking swap. Have you had the chance to run the 1/4 with it?
That particular engine is in my primary show car. I am not really into drag racing and have enough invested in this restored 88 Mera that it is unlikely to make a timed quarter mile run.
That particular engine is in my primary show car. I am not really into drag racing and have enough invested in this restored 88 Mera that it is unlikely to make a timed quarter mile run.
Nelson
Roger that, totally get it, different strokes for different folks.
Roger that, totally get it, different strokes for different folks.
This is another 88 Mera project car that I might consider running a quarter mile after the engine is tuned. The exterior is ugly but paint will eventually cure that.
This is another 88 Mera project car that I might consider running a quarter mile after the engine is tuned. The exterior is ugly but paint will eventually cure that.
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