i hear a lot of people running 10 psi (sometimes more) on stock internals. i'm assuming that this pressure and heat is run for a short time like 0-60 sprints, dynos, 1320, etc...but i'd like to know if the stock pistons can take stress for a longer period of time.

the reason i'm asking this is because i plan on using my soon to be turboed, daily driven B16 for the auto-X. it will be running a T25 at 7psi. depending on which pistons i choose, i'll end up with a 9.3:1 or a 9.7:1 CR. even if i lower the CR more, i don't know if the pistons are capable of the heat for a minute at a time since i haven't really heard/read much about it.

if anyone has any experience with this or even some theoretical advice i'd like to hear it. TIA

 

you should be fine at that power level but I would def suggest an oil cooler, upgraded radiator or both. That small of a turbo puts out a lot of heat even at only 7psi so heat management is gonna be a big issue in reliability for you. Do B16's have oil squirters for the pistons? Maybe look into water injection too. I would wrap your exhaust manifold to keep underhood temps lower and give your turbo a cool air pick up.
good luck! that turbo should be perfect for auto X but won't make much power past 6K.

 

after thinking some more, it looks like i'll end up using the OEM pistons that will yield a 9.3:1 CR.

the oil cooler and radiator have already been included in the equation, but with a bunch of things going on in my low capacity brain i forget about the oil cooler every once in a while. so thanks for reminding me. those 2 things should help the oil squirters keep the inner engine temps down.

does anyone else want to comment on stock pistons being able to take turbo heat for 60 secs per run? TIA

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Initial DA6 &raquo;</TD></TR><TR><TD CLASS="quote">...

does anyone else want to comment on stock pistons being able to take turbo heat for 60 secs per run? TIA</TD></TR></TABLE>The pistons only see really intense heat at full throttle, and during an auto-x you're practically never going to be WOT for more than 5-6 seconds in a row. Most of your time is going to be spent off throttle or light throttle in braking zones, corner entry, apex, and corner exit and I doubt that your engine would see more than 15 seconds total of WOT during a 60 second run. Just my .02