With my Shelby put away for the winter, I'm thinking what to do to it over the winter for mods, if any. I am at 717 hp at the rear wheels, 740 lbs tq, which puts me at 825 or so at the crank. Mods include so far: ported and polished TVS and elbow, VMP 2.4 upper pulley, VMP Idler pulley, VMP 67 mm tb, JLT Big Air CAI, 93 octane tune done by Pete at Performance Dyno in NH. Car runs awesome with no issues at all. Other mods were done like FRP axle backs, upper and lower control arms, relocation brackets etc etc, all stuff I know has nothing to do with hp. So my question is, what mods will help me squeak out another 20hp or so at the rear wheels ? Attached below is my last dyno run if that helps. I know 850 hp is just a number and varies with weather conditions etc. but seeing if I can get to the 850 number without going crazy. Do not want to go into the motor at all, been there done that and wont go there again. Like to here some suggestions as to what to do.....TY
Winter mods for 850 hp ?
- Thread starter blue 07
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Kooks longtube headers, off road H pipe, with no cats, will get you there.
At that power level I'd go E85. You are close to limit on 93. E85 will get you plenty of power and safeguard from going lean.
I'm going to switch in the Spring, just saving up for the Injectors.
I'm going to switch in the Spring, just saving up for the Injectors.
FWIW, I think you're at a (perhaps the) sweet spot for these cars. It's the top-end of "bolt-on" power before more extensive (and expensive) fuel and internal mods are called for. Rather than chase a specific number, I went with almost identical bolt-ons and told myself whatever my tuner safely extracted would be good enough. (Our power levels are similar, though yours seems more typical of cars that have at least some exhaust upgrades.)
It's sacrilege to some, but our current power levels feel "good enough" to me, especially when I remain comfortable that we're in little danger of damaging the engines as long as we don't push them too close to redline. Obviously, YMMV.
It's sacrilege to some, but our current power levels feel "good enough" to me, especially when I remain comfortable that we're in little danger of damaging the engines as long as we don't push them too close to redline. Obviously, YMMV.
I will agree with you on that. The car drives perfect and would hate to go in the wrong direction with internals. E85, doubtful
I know that would work like you and cobra therapy said but I don't know how much my neighbors would like me ! LOL. With the FPR axel backs I have on there now it is loud, would not delete cats since a nightmare up here getting a insp. sticker but maybe just the headers. Kooks, Stainless Works, anyone had experience with a set on a 13 GT500?
I agree but he lives in NH and like CT there are no E85 pumps available. Well, CT has 2 actually but none local to me.
If he gets an Nguage its simple to switch tunes but most ppl dont want the aggravation of draining gas and filling up with E85 which is why im going with a dual fuel system over the winter so I can switch at any time. Personally, I think ppl underestimate the power that comes from E85. U just make so much more dam TQ its crazy!
This is a great video to watch in general cause its a badass street car but if u skip ahead to the 5:00 mark u can see his dual fuel setup and he explains how it works.
Or the OP could opt for a Boostane tune at 100 octane but that will require adding Boostane each time he goes out. I do, its no big deal. I buy the 5 gallon and it last me most of the season.
If he gets an Nguage its simple to switch tunes but most ppl dont want the aggravation of draining gas and filling up with E85 which is why im going with a dual fuel system over the winter so I can switch at any time. Personally, I think ppl underestimate the power that comes from E85. U just make so much more dam TQ its crazy!
This is a great video to watch in general cause its a badass street car but if u skip ahead to the 5:00 mark u can see his dual fuel setup and he explains how it works.
Or the OP could opt for a Boostane tune at 100 octane but that will require adding Boostane each time he goes out. I do, its no big deal. I buy the 5 gallon and it last me most of the season.
My 2013 made 680rwhp with the mods below but with a VMP twin 67 TB instead of the now listed KB Mono Blade. After the 168 KB Mono Blade + Matching O-Sized Plenum the car pulled 716rwhp thru 410 rear gears. That's 37rwhp gain on that bolt on mod. Torque remained almost same at 679-680 but the Power Curve was flatter to redline. The car was Lund Tuned. The KB Mono Blade requires transfer of the electronics servo from your original TB. I believe this was a factor in ease of tune.
BPS no longer makes their XBA KB bolt matching Plenum which was an exclusive contract with Power By Hour. But I think VMP makes an adaptor for the KB. If you had similar gains that would put you closer to 750rwhp. I did H-Pipe AMR headers back in 2014. That netted 21-22rwhp gain over stock pipes with JBA X-Pipe.
BPS no longer makes their XBA KB bolt matching Plenum which was an exclusive contract with Power By Hour. But I think VMP makes an adaptor for the KB. If you had similar gains that would put you closer to 750rwhp. I did H-Pipe AMR headers back in 2014. That netted 21-22rwhp gain over stock pipes with JBA X-Pipe.
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Lower pulley and headers will easily net 25 additional hp.
OP.....Just curious if you're on stock gears? But also ....thinking if we consider 15% drivetrain loss at 850HP ...that's 850fwhp x .85 which equals 722rwhp. So you're not really far off. Or...we can all just say you make 850FWHP lol 
->) !
->) !
No one looks it, or wastes the time to speculate on crank HP anyway... just shoot for 800whp and call it a day OP.
What brand of headers and a lower pulley do you suggest ?
I don't think its recommended to run a 2.4 upper in conjunction with a lower 10% or 15% on PUMP GAS. If you have a Track Pack car, modifications will have to be made to fit the 15%.
Headers, American Racing is what I am installing after comparing to Kooks.
Both are good, each brand has it's own nuances.
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