This is a common question asked about all types of engines throughout the years so I thought I would try to get input from you all and post the results here in the first post.
The question is.. How would you go about increasing the HP and Tqr of the 3800 starting with bolt-on goodies first and working your way up, this way, people with different abilities and funds could see how far down the list they could go and what they could expect for their efforts.
I think the same things would apply to the NA and SC versions with exception of the supercharger and at some point you would need to lose the supercharger and go turbo then move up from there so.... The first thing usally mentioned to do first is headers. Not much HP gains (5 HP) ? but its needed for the later upgrades. List the upgrade and an approximate Price/ HP gains (if you know) from that upgrade. Im open for any opinions concerning this post also.
Let the list begin and I will edit as we go.
The 3800 Horsepower List
NOTE: After most any mods, rockers, cam, smaller pully, injectors, ect..., you will need to get your ECM reprogramed for the engine to run properly and get the most out of your new mods.
1. Tune______________? HP
2. 3.5 pully___________20 HP...Can be ran on stock series 2 engines (series 3 should run a 3.6 with 180* Tstat, colder plugs, cold air intake and TB spacer)
3. 3.4 pully___________25 HP...With this pully you should also run a 180* Tstat, colder plugs, cold air intake and a N* TB with adapter/spacer. A larger tensioner pully or smaller belt is required. KR starts to show up with the 3.4 pully running 91 octaine. With 94-95 octaine or an intercooler, KR should be no problem.
4. Headers___________5 HP
5. Ratio Rockers______25 HP... 1.8 :1 or 1.9:1 will bolt in and run with the stock valvetrain and stock cam.
6. Intercooler____10 to 50 HP
7. Injectors___________? HP... Stock 33# injectors should be good on a 3.8 down to a 3.1 supercharger pully.
8. Camshaft_____30 to 50 HP... A ZZP VScam will add around 35-40 HP and a XPcam will add around 45-50 HP. ( Note you will not want to run both ratio rockers and an aftermarket cam. Run one or the other)
9. 42# Injectors______ ?HP
[This message has been edited by JumpStart (edited 10-06-2011).]
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07:25 AM
PFF
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whodeanie Member
Posts: 3819 From: woodstock,Ga.,USA Registered: Jan 2008
smaller SC pully's are a fast easy HP gain. Cold air intake the best way to get as much HP you can is a good tune done on a dyno. under drive pullys intercooler gen 5 blower and intake cam rockers port match intake and heads larger TB NOS get an NA block and put a SC on it. turbo
this list is not in order I was just listing all I could think of.
this motor is the same as any other as far as power adders that have been done forever. the 2 keys I have found for this or any setup in a fiero is a good tune and find ways to keep them cool. they will all loose power once they get heat soaked so the best thing you could do is find ways to keep them cooler for longer. I have seen fan setups, intercoolers, chill boxes, vents, header wrap, hood vents and scoops and much more. keep in mind that this is not a be all end all list and everyone has their own was to do things. 300 seams to be a great # for the fiero as a driver you just want to have fun with. it is easy to get to and you can drive it every day with no problems. the more power you make the more work you will have to do to keep it going and they get to a point that driving them is no longer fun for every day. just my thoughts on it from what I have done in the past. I have driven cars from 50 HP to 3000 HP
PCM tune cam = 30-50 hp = 400$ intercooler = 10-30 hp = 200-1000$ port and polished heads with bigger valves =10-25 hp= 300-1000$ It is a very hard list to make, only becouse no two engines will gain hp the same way. Even with the same modes.
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09:25 AM
JumpStart Member
Posts: 1412 From: Central Florida Registered: Sep 2006
I do agree completely that all engines will be different but the HP gains should be around the same. Yes putting a mod (like a cam) in a 30,000 mi 3800sc and putting the same cam in a 200,000 mi 3800sc would have completely different results but I am assuming that anyone wanting to beef up the engine would atleast start with something that has been checked out and known to be in good shape.
As you stated Dean, A smaller pully is an easier way to get more power and something most people can do, but what needs to be done before adding the pully to get the benifits from it? I know that, at a point, you need to add an IC before going any lower (in general) or you can get KR. I have also read that you can only go so small because the M90 is maxed out at that point.
You cant throw on a 2.8 pully on a stock engine and it work right, or for long. I just thought this thread could help people that dont know about this stuff from making mistakes like that. Thanks for the input.
The first question to be asked is how much do you wish to spend and how much horsepower do you wish to make?
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, ZZP Intercooler, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, 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 "
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05:59 PM
JumpStart Member
Posts: 1412 From: Central Florida Registered: Sep 2006
The first question to be asked is how much do you wish to spend and how much horsepower do you wish to make?
Not sure what the HP limit is using an M90. Im guessing its between 300 and 400 HP but as Dean mentioned, 300 or maybe 350 with 300 WHP would be a good number to shoot for.
Steve
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07:00 PM
Dennis LaGrua Member
Posts: 15722 From: Hillsborough, NJ U.S.A. Registered: May 2000
Not sure what the HP limit is using an M90. Im guessing its between 300 and 400 HP but as Dean mentioned, 300 or maybe 350 with 300 WHP would be a good number to shoot for.
Steve
To make that type of horsepower we are talking performance cam, high capacity fuel pump, valve springs, headers, performance 3" exhaust, porting ,a small pulley, larger injectors , larger TB , larger MAF, an intercooler and ultimately a turbo with 15 lbs of boost.
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08:05 PM
RotrexFiero Member
Posts: 3692 From: Pittsburgh, PA Registered: Jul 2002
Money should all be at the forefront of these conversations even though guys like me slowly add performance adders as the money becomes available. In saying that the 3800 SC is a great platform for making good power, and more than adequate power for the Fiero.
The Fiero is a car that should have at least 200hp, and what I found is that the 2.8, 3.1, and 3.4 are at tops 200hp engines. The nice thing about the 3800 is that it starts at 200hp and you can, if you want, go crazy and turn it into a rocket!!!
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09:13 PM
MadMark Member
Posts: 2935 From: Owosso, Michigan, USA Registered: Feb 2010
Well, I have a 3800 SC III that has been slightly modified by Ryan at Sinister Performance. I have never had it dynoed at least not yet. The slight mods were to have the front exhaust ground out to increase flow. According to Ryan the rear one is fine. I added 1.8:1 rockers instead of the stock ones. I have a 3.5 inch pulley on the blower and a North Star throttle body. Ryan estimates that it is producing around 300 hp at the crank. I don't/won't know for sure unless I put it on a dyno somewhere. My goal was to have a good running Fiero with almost stock engine that should last for quite a long time. If I go to the 3.4 inch pulley I start to get a couple of degrees of KR, which I don't really want.
Polishing the intake and exhaust ports on the heads will help the flow too, but how much I don't know. Adding or changing the cam will give you some more HP, but you will most likely need to change to heavier springs on the valves, which would then put a strain on the cam drive chain. If you change to a heavier duty cam drive chain then you lose the balancer so the engine will idle rougher and a 3800 does not idle too well already. Doing more work on the heads will gain some HP too, but it then gets pretty expensive.
For me I still want to have an almost stock engine that I can count on for everyday driving. Even with that though I have talked quite a bit with Ryan about going with a Turbo instead of the Super Charger so that I can use an air to air intercooler with my mostly stock engine with about 10 to 14 lbs of boost. This would not put too much strain on the engine and would boost the HP up significantly while still maintaining drive ability and gas mileage. It is expensive though.
There are certainly other ways to boost your HP, but this is the way I want to go. It all depends on whether I can come up with the bucks to do it.
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10:37 PM
PFF
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Sep 20th, 2011
whodeanie Member
Posts: 3819 From: woodstock,Ga.,USA Registered: Jan 2008
just to give you an idea of what our last car did. and the mods we installed.
new rebuilt motor with all new bearings, rings, bolts, oil pump and gaskets. mods.. 3.4 pully, ZZP fuel rails, custom built headers, Cold air intake, 104 plugs, 160 thermostat and a tune. no other mods the car did 298 RWH on the dyno. this is one that shocked me it was more power than others that have had more mods done but we had to spend lots of hrs on the tune tweaking it to get full power without killing the motor. it is still a driver as well. D.
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07:32 AM
Dennis LaGrua Member
Posts: 15722 From: Hillsborough, NJ U.S.A. Registered: May 2000
Originally posted by MadMark: If I go to the 3.4 inch pulley I start to get a couple of degrees of KR, which I don't really want.
I can attest to that. The series III engines with the redesigned Gen V superchargers make more boost to begin with. When you add the 3.4" pulley to this engine, even with a 180*F stat, 3" exhaust and supporting mods a couple of degrees of KR will be seen at several points in the air mass vs RPM chart on the scanner. That is why an intercooler with a fairly large front mounted heat exchanger and high flow pump is now on the car. We've tried all different tweaks to the PCM program and the KR's won't go away completely without intercooling.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, ZZP Intercooler, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles, 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 "
..The best modification for the 3.8 is to have a professional flow bench port job,,this is also true of the 2.8,3.1 & 3.4 V6..
..no other modification will come close to producing the power that porting the head & port match will turn out with a simple opening of the ports at the valve seat & mild work in the bowl area you will also improve gas milage ..this is the only V6 that can come close to the 4 cylinder duke on highway milage with proper automatic.. ..the 3,8 is one of the best engines G.M. produced, the supercharger or turbo screws this engine up but does produce great horsepower. the 3.8 with minimal modifications will really improve the fiero ,,if used with the GM pontiac V8 4 speed automatic you can achieve fantastic gas milage & A car that has great power.. 95% on this forum will want the supercharger,,but the 3.8 with out turbo ,without supercharger is far superior ..I have not convinced one person of this in 4 years because style is more important than function with gearheads!!
because style is more important than function with gearheads!!
If by "style" you mean performance, then yes... Not everyone care about getting the best MPG from there Fiero; some of us "gearheads” want a reliable (i.e. stock or mildly modified) weekend toy
Originally posted by ALJR: If by "style" you mean performance, then yes... Not everyone care about getting the best MPG from there Fiero; some of us "gearheads” want a reliable (i.e. stock or mildly modified) weekend toy
Of course, porting, and polishing everything mirror smooth, tends to detract from MPG, because it reduces the amount of mixing of the air/fuel by turbulence induced through surface features as it travels through the intake port, as well as messing with the swirl inside the chamber. Velocity is good for bumping power, but it doesn't give you better economy. Not to mention that doing it right with a CNC and going back and forth between flowbench and CNC, is very costly.
Would be nice if there were 3D models of everything that could be used in a virtual flowbench/dyno application, but alas. GM engineering probably has some for whatever insanely expensive, proprietary, custom application they have for it. A lot of changes that went into the L92 heads was all done virtually.
... according to John and after owning and racing the car, I beleive it all to be true... Full modified 3800 cc 1989 Buick Park Avenue. Rated at 265HP/275 ft/lbs. Custom intake manifold with custom fuel injection. Custom ground Engle cam Crane 1.6:1 full roller rockers installed on Chrome Moly rocker studs Heads shaved to a 10.14:1 compression ratio Valves are high Titanium content swirl ground with matching three angles to the seat True dual exhaust system Custom aluminum valve covers 50,000 volt brick style coil pack (painted body color with piggy-bak ignition module) Matching teal green Spiro_Pro ignition wires
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04:09 PM
Oct 11th, 2011
JumpStart Member
Posts: 1412 From: Central Florida Registered: Sep 2006
I recently dynoed a 3800 SC Series II engine that was recently installed in one vehicle and it had 258 HP at the wheels and around 300 ft lbs torque. I have the curve if anyone wants to see it. This was a refreshed stock engine with a 3.4 pulley, cold air intake at the vent, and a decent tune. By tomorrow I should have numbers on a 3800 SC series III engine with a N* TV, VS cam, intercooler, vent type cold air intake, and 3.4 pulley. I will post those numbers as well as the recent 383 install after they are dynoed tomorrow.
I got the dyno results Saturday morning and will pass them on for future reference. The Series III SC engine with mods was jussst below 300 HP at the wheels with about 308 ft lbs of torque. The 383 is a torque monster at better than 400 ft lbs of torque but not a real high HP engine with less than 300 HP. I may consider some mods to this engine but likely will be content to use it as a show engine due to the use of colored anodized fittings, SS braided hoses, and some nice engine colors.
Nelson
[This message has been edited by hnthomps (edited 02-18-2012).]
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07:33 PM
MarkS Member
Posts: 694 From: Flemington, NJ Registered: Mar 2006
... according to John and after owning and racing the car, I beleive it all to be true... Full modified 3800 cc 1989 Buick Park Avenue. Rated at 265HP/275 ft/lbs. Custom intake manifold with custom fuel injection. Custom ground Engle cam Crane 1.6:1 full roller rockers installed on Chrome Moly rocker studs Heads shaved to a 10.14:1 compression ratio Valves are high Titanium content swirl ground with matching three angles to the seat True dual exhaust system Custom aluminum valve covers 50,000 volt brick style coil pack (painted body color with piggy-bak ignition module) Matching teal green Spiro_Pro ignition wires
I think I remember that car, written up in one of the old Fiero publications, maybe FOCOA ? Nice. Part of the inspiration behind my 3.8 project..
BR's
Mark
------------------ 86 SE V6 4 speed 86 SE V6 Auto 2008 G6 GT "Street" Coupe 2005 Buick 3.6 Rendezvous 2001 Olds Silhouette (AKA The Band Van)
