[SeanPlunk]

Originally Posted by Ryridesmotox

Have you tried running it on E85. There are guys running up to 30 degrees of advance on stock ecotec LSJ blocks with over 25 psi with a turbo. E85 is great for a boosted motor. It runs cooler, has an O2 molecule attached to it, takes longer to burn, is harder to burn, and allows for a ton of advance. With an intercooler and E85 you could probably run easily into the 20psi range.

I've looked into doing it on the Cobra (700+rwhp with a Whipple 2.3), but their simply aren't enough stations in the area to do it.

[enkeivette]

Big G is right, I spoke with a guy over the phone at JE pistons. He told me that there are two different materials they use for forging, and with the better blower pistons they use a stronger material. Mine aren't.

So it looks like I might be going with a set of all new domed pistons. Or... might just replace the one and intercool. He said the intercooler might be enough to make them last. Might just get this thing running again for now and wait till I find a job to go crazy and do the first gen Camaro thing. Then do it right, bore out the block 60 over, new pistons, new head studs, new HGs, better clutch with my T56... in a 1st gen Camaro.

[enkeivette]

I like street gas, I want to be able to fill up wherever.

[enkeivette]

Also, the JE tech said my timing is already so LOW that it might cause problems. He said having it too retarded can also cause heat build up???

[enkeivette]

Skunk nailed it on the head, 2618 is where it's at for high boost.

[Ryridesmotox]

I hear you about the E85 being hard to find but it's worth it. And on my car its good for another 40hp at the wheels, for a V-8 car its even more. In regards to you timing questions, the reason that too much timing retard will cause excess heat is two fold... Ok one the combustion will continue while on the exhaust stroke of the motor. Two, that will translate to combustion going on inside the exhaust ports and headers. New engines have a "catalyst warmup cycle" that does this on purpose to heat up the cat quicker. My car would run at about 3/4 throttle with -10 degrees of timing... It sounded like the combustion was taking place at the turbo haha its so loud on a straight pipe.

Also, not to be a nag or anything, I would probably say get a whole new set of pistons instead of just two that you need to replace the broken ones. If it damaged two of them, chances are that the other ones have been weakened as well. Its totally your decision of course but I wouldn't want to put everything back together just to take it all apart again next month.

[94cobra69ss396]

I wouldn't pull more timing out thoughout the entire rpm range. You can run more timing in the lower range where you're not making as much boost. I'm not sure how much boost you have at 3000 but the Cobra only has about 3psi. With that boost retard that I link you could set it up to pull 1-3 degrees of timing per psi of boost. If you are making 13 psi and set it to 1 degree it would pull a total of 13 degrees.

So say you have the initial timing set to 14 degrees and you have another 20 in mechanical advance set to be in by 3000 rpms. If you are cruising at 3000 rpms with vacuum you'll have 34 degrees of timing. If you jump on the throttle and have say 3psi timing will be pulled back to 31 and so on. Once you are at 13psi you will have 21 degrees. This will help in both the lower and mid range power as well as help keep it from detonating.

Now this is in no way a replacement for an intercooler, I'd suggest getting one when you can afford it but it will help you run pump gas without one and is a lot cheaper.

On a side note what's with the dome piston? How much static compression do you plan to run? With your static compression of 9:1 and 13psi of boost your dynamic compression is around 16:1.

[Ryridesmotox]

^^^ Do this. Great idea, but as boost and heat build you might need to pull more than one degree per PSI, which is what he said in the beginning.

Enkei have you tried methanol injection to cool the charge down? It is initially cheaper than an intercooler and can add some power as well. It only comes on at certain throttle demand levels.

[94cobra69ss396]

The problem with running methanol injection is that you have to retune for it. Then if you run out during a full throttle run his pistons will look like they do now. I have a Mr Freeze system that I installed on the Cobra years ago but never tuned for. If you want to give it a try on the Vette you're more than welcome to it.

Here's a link to what it is http://www.andersonfordmotorsport.co...emart&Itemid=1

I also have 3 one gallon bottles of Snow Performance Boost Juice http://www.snowperformance.net/product.php?pk=3.

It's over at GTR for sale but if you want it let me know and I'll go pick it up.

[Ryridesmotox]

Originally Posted by 94cobra69ss396

The problem with running methanol injection is that you have to retune for it. Then if you run out during a full throttle run his pistons will look like they do now.

This!!! Care must be taken while running meth. I guess I'm just used to tuning for everything. I have literally loaded 20 different tune files on my car for different stuff... Next will be an E-85/91 octane mix. He would need a tune for E85 as well.

I still highly recommend E-85, it is worth it. It literally is magic for a force induction motor. It's usually available at smaller stations that aren't linked to a mobil, shell, or chevron.