3800 SC - Trying to squeeze out a few more HP (Page 1/3)
DimeMachine JAN 29, 09:50 AM
Cold as heck out in MN so I spent some quality time recently working on the 3800 Supercharged Fiero project.

Working on mods to the intake manifold and then will do a little porting to the supercharger. Hoping to set a presonal best this summer.....




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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

Dennis LaGrua JAN 29, 02:44 PM
If you want more efficient boost try adding an intercooler.

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" 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 "

DimeMachine JAN 29, 08:54 PM

quote
Originally posted by Dennis LaGrua:

If you want more efficient boost try adding an intercooler.




If it was cheap - I would give it a try and see to find out for sure with my current setup - but it is a pretty big $$ and time investment to do it right.

If all I had was 91 Octane - I would absolutely add an intercooler and I think it would yield very nice gains because of the cooler air (more oxygen) and perhaps more importantly all the timing you can add (with a 91 octane) being 80 degrees + cooler (intercooled vs non-intercooled)

That having been said - since I have E85 (and my setup is not currently knock limited) - it can handle all the boost the stock m90 can throw at it with a 2.8 pulley and a VS cam without an intercooler for short periods of time - like drag racing. The IC core that fits under the M90 does an excellent job of cooling the air - but there is no free lunch. The IC core is so small - I think it significantly restricts flow leading to quite a bit less boost after the cooler (than if it was like a large IC core for a turbo setup). I think this negates most of the gains - making it a pretty expensive mod for limited gain (assuming one has E85 availability).

If I had a pile of money and a dyno - I would test this!
pmbrunelle JAN 29, 09:48 PM
At WOT, are you able to run MBT spark?
claude dalpe JAN 29, 09:51 PM
DimeMachine,

When I had my stock 3.8Sc with a 3.5 pulley I don't remember the exact numbers but let's say 10lbs of boost
when I redid the intake gaskets for the aluminum ones and at the same time I decided to slightly ported the supercharger and the intake too
And I remember well that afterwards I had slightly less boost than before.
Try to find out about this subject but I think you will have to change your pulley
La fiera JAN 29, 09:59 PM
Hey Dime!
Forgive Dennis, sometimes he speaks before he thinks, but he means well. Everyone including you are fixated in power to make your ride quick but how about making it lighter. You should look into getting rid of everything unnecessary in your Fiero. That's the problem with altering atmospheres to make power, we loose the ability to think.
The lighter your car is the faster it accelerate, stops and go through corners. In your case you are looking for acceleration so lightening your car is the best way to get quicker this coming summer.
Another thing you can try is the use of a 5th injector. Not for fuel but use it to take advantage of the cooling properties of E85.
Since the compressor heats up the air before entering the combustion chamber, how about injecting a mist of E85 right after the TB? The idea is to grab all the heat out of the incoming air so when the compressor squeezes the air and heats it up, the incoming air will not be as hot because most of the heat has been absorbed by the alcohol.
I had a 2.5L 4 cylinder 8 valve Dodge turbo and that's how I managed to do 415WHP and 465WTQ on 93 pump gas. In my case I use water injection, not meth injection, I did R&D for Snow Performance when he was working out if his garage! I used two injector nozzles, one before the TB and one on the intake manifold.
I hope you get quicker!
LFiero67 JAN 30, 12:01 AM
Adding an intercooler took me from 11.8 to 11.4. Both with 2.6” pulley. They are way cheaper than they used to be. At your level, other than a turbo swap, it’s going to be tough to make significant gains.

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10.007 @ 135.54MPH. <-- Video
Best 60' 1.42
Best mph 138.82
Billet 6262 Precision turbo, PT1001 intercooler, ST1 cam, 140lb springs, comp pushrods, HV3, stock L32 bottom end and heads.

Old M90 XP Cam time -
11.425 @115.60
1.543 60'

DimeMachine JAN 30, 02:22 PM

quote
Originally posted by pmbrunelle:

At WOT, are you able to run MBT spark?



Yes - thanks to the E85.
DimeMachine JAN 30, 02:26 PM

quote
Originally posted by claude dalpe:

DimeMachine,

When I had my stock 3.8Sc with a 3.5 pulley I don't remember the exact numbers but let's say 10lbs of boost
when I redid the intake gaskets for the aluminum ones and at the same time I decided to slightly ported the supercharger and the intake too
And I remember well that afterwards I had slightly less boost than before.
Try to find out about this subject but I think you will have to change your pulley



I am already at a 2.8 pulley - wonder if I should go 2.7?

Hopefully I won't make the blower worse- I have spent a considerable amount of time researching so I intend to only perform a modest amount of porting so as to hopefully not mess it up!
claude dalpe JAN 30, 08:55 PM
You said: Hopefully I won't make the blower worse !
Me I dont thing I mess with my porting I just think when you port something you enlarge the volume d'intake
And when you enlarge this volume you have to put more speed from the blower to make the same boost pressure
I am not a spécialiste but is what I think.