12 GT500 Upgrade

98TA

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Alright fellas, been doing some searching and brain is spinning and my last mod motor was a 12 GT500 back in 2014 and I left it alone.

Car currently has a Whipple 2.9 with 3.0 pulley, 75lb injectors (no idea as to brand- just purchased car and its not on build sheet from PO) JLT with a VMP SCJ throttle body, AFCO heat exchanger and SCJ tensioner. O/R x pipe
I have dyno sheet from PO showing 706 on a mustang dyno. I'll be hitting the dyno here next week to verify power, AFR etc.

1: What do these normally get spun to? Rev limiter is set at 6,500- seems low and dyno sheet it seemed to still be pulling when they shut it off.
2: What's the ticket to run E85? Return style fuel system? Or drop in some new injectors and pumps?
3: What's a safe power level on stock block?
 

1Kona_Venom

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1. pull the whipple replace with VMP Gen3R
2. stock block = keep shifts under 6400-6500 RPM unless you want a new window in your block
3. Max power on 93, generally, 750rwhp

I'll let the E85 experts answer the rest
 

Catmonkey

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Safe level is 550. Most failures are the result of pushing it over the 6,500 rpm redline. The engines have long strokes and pistons speeds are quite high. Increasing rpm just exacerbates the speed. There's nothing wrong with the block, it's the OEM rods that are the weak link. These engine have proven to be pretty durable in stock form, but no one can guarantee that you won't break a rod even at your current power level. A good tuner can improve your odds and staying conservative with the tune can't hurt either. E85 will need bigger injectors. A return style fuel pump is the only option if your at max duty cycle on the fuel pumps. Making more power on E85 will not improve your odds for longevity, but it will decrease your chances of detonation. These engines are insanely expensive to build. If you have an engine failure, you're almost sure to lose the block and aluminum blocks are getting a little harder to find.
 

98TA

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Safe level is 550. Most failures are the result of pushing it over the 6,500 rpm redline. The engines have long strokes and pistons speeds are quite high. Increasing rpm just exacerbates the speed. There's nothing wrong with the block, it's the OEM rods that are the weak link. These engine have proven to be pretty durable in stock form, but no one can guarantee that you won't break a rod even at your current power level. A good tuner can improve your odds and staying conservative with the tune can't hurt either. E85 will need bigger injectors. A return style fuel pump is the only option if your at max duty cycle on the fuel pumps. Making more power on E85 will not improve your odds for longevity, but it will decrease your chances of detonation. These engines are insanely expensive to build. If you have an engine failure, you're almost sure to lose the block and aluminum blocks are getting a little harder to find.

Thanks. I'm just trying to learn the ins and outs of what these like.
Not looking to run E85 to improve longevity, but to make some more power safely and E85 is everywhere around here vs having to keep a drum of race fuel at the house. Been there done with my old F2 blown Z06.
 

Catmonkey

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550? Cmon
The man asked for "safe". If he asked for reasonable limits, I'd say 750. Granted many are getting away with up to 800, but others have not been so fortunate. Anyone adding 150-300 hp on a stock bottom end is rolling the dice. Each engine is different and some have proven to be more bulletproof.
 

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