24# of boost, stock compression and strait C16

[mulot30th]

I'm running JE 10:1s with the stock head gasket, which so far I'm pretty happy with, a little snappier than a head shim but more boost friendly at the same time.

its because you have much tigher quench with reverse dome pistons!!! and that is good to avoid detonation at same time.


Do you have forged rods in there? On mine the stock rods are what worry me the most since stock pistons will have no problems if I can keep it from detonation. but rods... they have their limits... and that is why I still haven't ran more than 18psi

 

[Need for Speed 2]

in the feild 24lbs is not doing what you think 28 turbos will go there but not efficiently 18lbs seems to be the sweet spot at 18hang on tight if she is tuned to perfection. every year the boost #s just keep going higher but in fact some may be going slower or closer to a sacrifical serving to the deto gods. kaboom. going to by some used apexs used motors are gonna be worth gold jerry gold i tell ya

 

[summitking]

sled

Need for Speed 2 but with a little higher compresion they will be making more hp at lower boost so there isnt really the need to keep going higher. Ive got some custom cut cams coming for my sled and the timing control box i plan on running 17 lbs on pump gas

 

[mulot30th]

I sure hope to get more seat time on this thing this winter to tune her correctly

but I am still afraid to go over 300hp on the stock rods... even if I can do it a 18psi (which seems pretty easy)

 

[Remmy]

Yes I put in carrillo rods, they make the stock rods look like No. 2 pencils in comparison. I wish I had pics of both side by side. I have heard mixed info on the stock rods but I would be getting nervous at 18 lbs w/ stock compression. I believe one of the Alpine boys lost a stock rod at that same power level. Not sure though, but Dean was telling me they're putting rods in all the high performance applications now. $$$$$$

CR

 

[mulot30th]

I will more than probably consider a rod upgrade and stock compression forged pistons in my future.

 

[MEAT]

Talk to Thomas800 about the stock rods and how tuff they are. it will surprise you.

 

[KnappAttack]

A stock piston and stock rod engine will go over 400 HP. JUST DO NOT DETO IT! Course you don't want to deto anything with boost, but pieces are likely to be scattered with stock stuff. Stock pistons are great, rods are the weak link.

 

[mulot30th]

A stock piston and stock rod engine will go over 400 HP. JUST DO NOT DETO IT! Course you don't want to deto anything with boost, but pieces are likely to be scattered with stock stuff. Stock pistons are great, rods are the weak link.

Of course I will not deto it!

I will always run good gas...

so far.. 18 psi and not a sign of a problem... its just a question of how far will I go before the rods go south on me...

 

[HAMMER]

Jim Czekalia (Dynotech Research)

Are aftermarket forged rods really necessary?

The stock Apex torque is about 76lb/ft at stock 150hp. If we double Apex torque to 150 lb/ft, equal to 17+psi boost 280+hp, boost peak compression loads on the connecting rods are only 20% higher than stock! Tension loads on the rods are equal to stock or less. The key here is that both NA and Turbo peak combustion chamber pressure occurs at about 18 degrees ATC. The difference is, NA combustion chamber pressure subsides rapidly, and boosted combustion chamber pressure holds its advantage longer, approaching 90 degrees. Since the peak compression loads on stock rods at 280hp is theoretically only 20% higher than stock, the stock rods should be adequate for 350+hp, and fears of catastrophic failure are unfounded. The stipulation is: If detonation is avoided !!! If you were ignorant enough to run high boost without the correct octane fuel or a bad batch of high octane fuel, detonation would be the result, which would cause loads on the pistons and connecting rods to be 10x higher than stock. The extreme loads of detonation will most certainly cause that feared catastrophic failure.

More Good Stuff: (Head, Cam, Ignition, Fuel, Compression, Intake, Exhaust)

IMPORT TUNER MAGAZINE (Not Overly Technical but Interesting)
http://www.importtuner.com/tech/index.html

TURBO MAGAZINE (Not Overly Technical but Interesting)
http://www.turbomagazine.com/tech/index.html

GARRETT TURBO (See Tech sections 101, 102, 103)
http://www.turbobygarrett.com/turbobygarrett/

ENGINE MASTERS (Good'ol American-V8 Technical Articles)
http://www.popularhotrodding.com/enginemasters/articles/hardcore

KB PISTONS (Good Piston/Compression Articles)
http://kb-silvolite.com/article.php