HP Estimate? Built Engine, 2.9 @26-27PSI, E85

04OWwhipple

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I'm bored at work right now so I figured I would see what people think my new engine should make. I was previously making 710RWHP on 21-22 PSI on my stock long block. I'm now currently built engine and pulley'd down and making 26-27 PSI. What do you guys think she will put down once I get around to dynoing her?


Engine Specs:
4.6L
9.2-9.3:1 Compression
Stock cams
Cobra crank
Oliver rods
MMR pistons with Valve reliefs
Gen 2 2.9 Whipple w/standard inlet
Fore fuel rails with twin 465 pumps
!D1300 injectors
E85
 

01yellercobra

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Are the heads stock? A buddy of mine made 790rwhp I think with Crower cams, ported heads, stock compression (I think), and a 3.4 with the Crusher inlet. So I would think high 700's for you. But from what I've been told that inlet is going to be a big restriction.
 

04OWwhipple

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So roughly .8 bump in compression and 5psi?

I'll go with 765

Correct, just a slight bump in compression.

Are the heads stock? A buddy of mine made 790rwhp I think with Crower cams, ported heads, stock compression (I think), and a 3.4 with the Crusher inlet. So I would think high 700's for you. But from what I've been told that inlet is going to be a big restriction.

Yes, the head are stock as well. I had some belt slip issues at first but over the weekend I think I got that sorted. During a 3rd and 4th gear pull it peaks at 27.5 and drops to about 26.0-26.5 PSI by 7000 RPM.
 

04OWwhipple

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should be right at 800rwhp give or take a few hp

That's loosely what I was figuring in my head. What would you start at with timing on E85 at that boost level decipha? Currently I have it just shy or 20*. Eventually I will start spraying the nitrous and I know I will have to back it off a bit when I do that, biggest shot will be a 150 wet shot.
 

decipha

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I would shoot 16 to it first and see where its at

with the n2o I'd start at 13 and go from there

its safer to work your way up rather than work your way down
 

04OWwhipple

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Nitrous on top of that boost level? That's gonna be a helluva ride.

I imagine it will be a bit white knuckle the first hit. I have never driven a car with nitrous so it shall be interesting for sure. I'm shooting for 900-1000 to the tires on the 150 shot.
 

01yellercobra

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I've never driven a nitrous car, but I've ridden in my buddie's cars that have it. It's fun and I can see how it's addictive. But I'll keep my boost. No need to mess with bottles and stuff.
 

04OWwhipple

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Just curious...any reason you didnt do cams while it was apart?

Sent from my SM-G970U using Tapatalk

The reason I didn't go with it is that I wanted my car back together and its current setup will do 900-1000 on stock cams. I figured that was enough for now. haha.

It's a bit of a long story but I installed the nitrous and Haltech after the summer was over and the weather went to shit here. Then when first tuning the Haltech, found out on the dyno that the stock long block had cracked right at the end of the previous season and I didn't even know it. So I yanked it to have the short block rebuilt, reinstalled it in the car and was still losing coolant. Ended up pulling it again and tearing the bottom end apart to find every single cylinder on bank 2 was cracked. End up getting the machine shop to buy me a new block and do the work all over again for free. Once things were getting back together with the second rebuild I was considering doing cams but it was another $1800 for cams and springs and really at the end of the day with my current combo on the spray it will be 900+ easily on the big shot which is plenty for me at the moment. And I figured I can always do cams in the future.
 

03CRUSHER

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What’s your lower pulley setup look like? Caged/unsupported? Pulley ring size?
 

GodStang

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SAE or STD? STD and a friendly Dyno probably 780-800 if you can keep that much boost cool. SAE I would think 750s. Your issue will be the stock noncrusher inlet.
 

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