Limits of stock exhaust and current injectors

[TenaciousRock]

I'm currently running the following mods:

-VMP Gen 2 Stage 2 kit (56# injectors, bap, 82mm pulley)
-Initial tune that shipped with the kit from VMP
-Billet OPG and crank gear
-Whiteline LCAs
-GT500 axleback

I don't have a boost gauge but I am assuming by car is roughly 10psi. I'm wondering at what point the stock exhaust is going to be a major restriction or if it is dangerous to run the stock exhaust at a certain point if there is too much pressure and at what point I'd need to upgrade injectors. I run 93 octane (E10), will never do E85 or full on race gas (octane booster MAYBE but doubtful)

When the supercharger was installed Rev Auto ran it on the dyno for me and it made 562/485. I'm thinking I can pay for a re-tune and make close to if not more than 600/500, but I am considering other upgrades to keep the car safe on the stock engine.

 

[Gruca]

Coyotes are limited by octane really. If you don't want detonation, you need to add things like off-road pipes, headers, etc to get over that 600 mark and still keep your engine alive. I'm sure people have turned up the boost and made it over that mark without those supporting mods, but the engine is a time bomb at that point.

 

[Jumpmaster2015]

OP, why will you never run E85? If you wanted to protect your engine, that would be the way to go. It is highly resistant to detonation. Horsepower wise 600 RWHP is well within the safe range, people run more horsepower than that on stock engines, even on stock exhaust headers. I would upgrade to high flow cats or get rid of them completely, because that would be your major point of restriction. There are plenty of threads that support what I just wrote, take a look.

 

[TenaciousRock]

OP, why will you never run E85? If you wanted to protect your engine, that would be the way to go. It is highly resistant to detonation. Horsepower wise 600 RWHP is well within the safe range, people run more horsepower than that on stock engines, even on stock exhaust headers. I would upgrade to high flow cats or get rid of them completely, because that would be your major point of restriction. There are plenty of threads that support what I just wrote, take a look.

I'll never run E85 because it is too inconvenient. The closest E85 pump is about an hour from my house and it's just a street car. I won't be taking it to the track (at least not enough) to make it worth it.

I also have to pass the emissions tests unfortunately and I've heard they're cracking down on turning CELs off, I know VMP won't do it because of legal issues. I don't want to have to keep swapping pipes or having other issues with the man lol.

 

[stangn]

My Whipple car has a 5.2 short block and makes 13-14 psi with an A6. With an off-road X pipe, stock headers, stock over axle pipes and GT500 mufflers. Car made 640 rwhp, I changed the headers to On 3 1 7/8 shorty's everything else stayed the same. Revised tune and first pull made 701 rwhp, cars on 93 so he backed it off to 682. Now that's an extreme case with same tuner and dyno. I never thought stock headers were a problem but I guess they were.

So more air in needs more air out.

 

[Jumpmaster2015]

My Whipple car has a 5.2 short block and makes 13-14 psi with an A6. With an off-road X pipe, stock headers, stock over axle pipes and GT500 mufflers. Car made 640 rwhp, I changed the headers to On 3 1 7/8 shorty's everything else stayed the same. Revised tune and first pull made 701 rwhp, cars on 93 so he backed it off to 682. Now that's an extreme case with same tuner and dyno. I never thought stock headers were a problem but I guess they were.

So more air in needs more air out.

I never thought about shorties for a boosted application, thats great data!