Thread: 325 +/- wheel horsepower?

Originally Posted by makenzie71

I'm looking at picking up a BMW 5409 with a tanked engine and I have access to a 2003 GTP that's all smashed up...and my desire to make weird **** work is driving me nuts!

Basic idea is to adapt the 3.8 to the BMW 420G 6-speed tranny so I can leave the driveline alone. If I can't pull that off then I'll source a T5 and adapt the drieshaft. The rest is tedious boring stuff with making mounts and plumbing systems and wiring.

What I want to know, though, is what would it take to push the 3.8 up to 325whp? We're talking a 100~120hp boost over stock. Will the stock bottom end be up for that? Can I get it by just cranking up the boost (smaller pulley)? What am I in for here? This is going to be what makes the project a consideration.

I have about 310 whp - here is proof. https://www.youtube.com/watch?v=XcFNm7F7GwU&t=3s

Ingredients.
1. 3800 series II stock
2. VS or XP cam
3. better front manifold as stock is very restrictive.
4. 60lb injectors
5. E85 fuel
6. Deatschwerks E85 rated fuel pump
7. some tuning on HP tuners.

Have fun!

Originally Posted by Toys4life C5

I have about 310 whp - here is proof. https://www.youtube.com/watch?v=XcFNm7F7GwU&t=3s

Ingredients.
1. 3800 series II stock
2. VS or XP cam
3. better front manifold as stock is very restrictive.
4. 60lb injectors
5. E85 fuel
6. Deatschwerks E85 rated fuel pump
7. some tuning on HP tuners.

Have fun!

What else needs to happen to be able to run E85? I may be looking to switch to that on my '07 GT if I can find somewhere around me that has it.

Originally Posted by madhavok09

What else needs to happen to be able to run E85? I may be looking to switch to that on my '07 GT if I can find somewhere around me that has it.

1. Some tuning with HP tuners. I have a 97 PCM so it may be different than an 07. Easy way is to lie to PCM as to injector size (tell them they are 30%+- smaller than they really) which leads to the 30% more fuel E-85 requires. Timing needs to be increased then quite a bit under high load/WOT areas for the E-85.
2. Research as many threads as you can find on the subject.

Originally Posted by Toys4life C5

1. Some tuning with HP tuners. I have a 97 PCM so it may be different than an 07. Easy way is to lie to PCM as to injector size (tell them they are 30%+- smaller than they really) which leads to the 30% more fuel E-85 requires. Timing needs to be increased then quite a bit under high load/WOT areas for the E-85.
2. Research as many threads as you can find on the subject.

I've been looking into it. Buy the sad part is I can't seem to find E85 near me at this time. It is something I may still look to do, but I'd just need to find a gas station. Thanks for the input.

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