I’ve got a 87 Fiero GT V6 w/ 5 speed. I want 375hp (goal is 300 at wheels) I would like to keep the money as low as possible. Has anyone done this? Is a possible for a 87-03 GTP engine to do this without a ton of money or would it be better to do a 3800 with twin turbo? Going to start acquiring parts- just doing my homework now before I drop any money and change plans. I’m going to switch to a 6 speed and will have it rebuilt before I put the engine in. Engine will be rebuilt also. The drivetrain will all be new or rebuilt when I’m done. Suggestions?
Deciding between twin turbo or s/c 3800
- Thread starter romainiac
- Start date
Fivefingerdeathpunch
New member
Opening the engine is not worth the cost, unless you like paying a machine shop or un-needed work. The factory bottom end will support 400-500hp all day long if you wanted it too. It's the fuel and tuning that keep it alive. If the engine is healthy don't even touch the bottom end.
If you want 300hp, that is fairly easy on a blower. Swap in a mild camshaft, something like a XP cam, drop the pulley size down to a 3.0 or 3.2 size and do free flowing exhaust. Add some meth or run E85 fuel and get a good tune.
If you want 300hp, that is fairly easy on a blower. Swap in a mild camshaft, something like a XP cam, drop the pulley size down to a 3.0 or 3.2 size and do free flowing exhaust. Add some meth or run E85 fuel and get a good tune.
WarStryker13
I break things.
Get a junkyard L67, toss a 3.0" pulley and headers on it, get it tuned and running on E85. The 3800 can make 600+ at the wheels with just one turbo, no need for two.
You'll spend more rebuilding a 3800 than it would cost to buy a running, driving GTP and pull the engine out.
You'll spend more rebuilding a 3800 than it would cost to buy a running, driving GTP and pull the engine out.
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GTPpower
New member
It's really easy to get that kind of power from a supercharged 3800.
Xp or s1x cam
Double roller
130# springs
Milled retainers
Viton valve seals
E85
60lb injectors
255lph pump
2.8 pulley
That will put you in the 330-350 whp range through an automatic. With a manual, you can probably get to 300whp just by switching to e85 and skipping the cam.
Xp or s1x cam
Double roller
130# springs
Milled retainers
Viton valve seals
E85
60lb injectors
255lph pump
2.8 pulley
That will put you in the 330-350 whp range through an automatic. With a manual, you can probably get to 300whp just by switching to e85 and skipping the cam.