how much psi for m30 before it goes bang?

[deian]

Just gathering knowledge here before jumping into the deep end with months of work on an E30 and M30B35/turbo....

I know only a few of us here have an E30 M30B35 with a turbo, i only know of Kos at the moment who's done this, Kos runs 5psi into it and gets 265bhp, say we try 8 then 12 then 15psi, how much bhp can be squeezed out of it, what about 0-60 times etc?? when would the engine go BANG, or when would the life of the engine suffer due to stress, we all know it's pretty much bulletproof, so any expert opinions?

what turbo shuld i get for it to squeeze maybe 300bhp out of it?

thanks, deian

[Andy_magic]

Thats not really a question that has a straight answer.

A motor will stay together as long as it's in good mechanical condition and managed properly.

A well set up engine running 10 PSI will outlast an underfuelling/under charge cooled one running 5 PSI.

Also a turbo running at 90% capacity will generate more heat than one running at 50% so selecting a turbo is critical, a balance of lag time v ultimate boost pressure.

It also depends how the cars going to get used, a quick road car would be better with a smallish turbo that spins up quickly otherwise it gets tedious waiting for it all to 'happen'

I feel Piggyback or standalone management is the way to go and a good session on the rollers mapping what ever system gets fitted.

My 2p worth

[Kos]

the problem is that there engines run a high compression ratio of 9.5:1, and remaping the ecu and retarding the timing can be quite hard. but even so the rods cant take much more than 15psi when you drop the compression.

at santa pod yesterday with 50hp of nitrous i ran a 13.9sec 1/4mile crossing the line at 101mph. thats using a 5speed overdrive gear box and a 3.25 diff !! so witha shorter diff like a 3.64 my 1/4 times should be the same with out the nitrous.

next year, i'm going low comp ecu re-map or after market and 350-400bhp with out nitrous, and changing the diff. i want to be in the 12's when i cross the line. thats the target!!

[Andy335Touring]

Have a look on here, plenty of M30 turbo's

http://www.mye28.com/cgi-bin/forum/foru ... y=&others=