Whats the most boost that the stock
- Thread starter Meatstick
- Start date
ok its like this. i had 40k on my msp that i had since last dec. cai,tt,and profecb spec 2 bc. I was driving at 11psi daily spiking to 11 1/2 12 at sea level in bay area cali. well 1 morning i was driving and noticed that i had no blow off when switching gears. got all the way home and had oil everywhere. but i noticed that i hit fuel cut bad on the freeway on my way home but i continued. so like i was saying oil everywhere took it to the dealership and they couldnt figure it out, replaced the turbo, didnt help oil in ic piping and all over. so we did a compression check and noticed that cylinder # 3 was off by 100psi. pulled the motor and checked all the pistons and rods and sure enough piston # 3 had a big azz crack. replaced the motor for free and no more problems. because they piston was cracked the oil was going crazy. they call it blow by so if you ever get these symptoms its not good.
we do have a forged crank and forged rods. forging is the process in which they are made, that doesn't necessarily make them big and able to take stuff. the rods are skinny, but they were created using a forged process, and thus are forged rods. not aftermarket strength forged, but forged none the less14LBS said:
and let's just say that the internals can handle more "boost" than the fuel system can.
i believe this exact question has been asked at least a few times too...
they cant handle more boost and the type of forged i was refering to was the aftermarket forged that could handle more boost under pressure without breaking. i think you need to blow a motor and take it out and experience it first hand b4 you add you .02 also see the pieces for yourself and put them in.... thanks......
jonnydoe48
Member
joep went 18 psi on stock everything (except it was on race fuel)
huh? was i rude?14LBS said:
the rods and crank are forged. period. being forged doesn't make them invincible. forging is a process, you can make rods as thin as a pencil using the forged process, and guess what, they're still forged rods. i'm not trying to say our internals are good, but the rods and crank are still forged.
and do you want to guess why your piston broke? more than likely, detonation. which is caused by? lack of proper engine management, most notably the fuel system in our case. and thus, the internals will outlast the fuel system's capabilities. this same thing could've happened with aftermarket forged everything, they can break under detonation too, they'll just survive detonation longer, not forever.
odds are i'm not going to crack a piston because i know the car's limits and know how to not blow up motors through proper upgrades, monitoring and ways to manage them. and if i do end up breaking something and i'm not bone stock, it's not going to be the part that broke's fault, it's going to be mine, just as it was yours that your piston cracked.
thanks...
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sounds like 14lbs knows his s*** he had that tuned and dyno tested with his standalone engine managment right? detonation killed your motor not weak internals just poor tuning on your part. the rod bolts and pistons are the weakest points and as I stated you need bigger injectors ,fuel and timing engine management, good tuning , rod bolts possibly pistons to really feel safe at 11psi - 13psi .Even if its just spiking to this boost. above that I think full piston and rod swap with rings on pistons setup for turbo car. I could go on and on but it seems like a waste to try to educate people who just want to turn up the boost with no tuning or fore thought. Just my .02cents
i havent seen the stock internals of our car but u can go a lone way with tuning properly......alot of cars can take a good beatin as long as u stay away from detenation.....not a good comparo but the nissan sr20 motor has been tested, dynoed, and shown to hit over 450whp on the stock block and nuttin but a metal headgasket......i think its a matter of tuning then goin out and spendin tons of dinero to build ur motor just to hit 13-15 psi.....oh and i have seen many ppl blow ther "built" motors because of detonation, again a good reason to spend ur hard earned money on proper engine management over building up ur motor.....in the end, as stated above, i think alot of the motor blows on here are cus ppl got happy with the boost knob
jonnydoe48
Member
jred321 said:
did i say he ran that everyday or something in my post?
yea you guys speak of goin happy with a boost nob but look at every1 on this forum claiming to be boostin 12 daily if not more. I know all about the tuning and fuel so b4 you think that your educating some1 about engine management you need to go and do your homework on the car. Lets see i believe that i started tweeking with the msp motor b4 you so dont trip.
since you knew what you were doing, what were your a/f ratios? your injector duty cycles? how far advanced was your timing? these things would help you to know why your motor broke, and you must have this information because you know what you're doing.14LBS said:
we have done our homework on the car, we haven't blown up our motor.
many of the people running high boost 1) are flirting with danger and haven't driven 40k yet so nothing bad has happened, 2) have taken other precautions, and/or 3) are at a different elevation and temperature, and thus getting less air than you for the same boost pressure
