I want to put a turbo in a 2002 z28. My question is... What do i need to do to the motor its self to keep it from blowing sky high? And, What is the max PSI a stock LS-1 can handle?Also along with the previous question, Howmany PSIis the motor putting out using stock parts and stock settings?

thanks for your help

 

Technically you don't need to do anything to the motor in order to boost it. If you run on stock internals you don't want to push anything over 8 pounds of boost though.

I need some clarification on the second part of your post...right now it's not boosted at all, so you don't have any "extra" PSI when it's stock. Stock compression ratio is 10.3:1.

 

see thats my thing, im not educated past a high school shop class on internal combustion engines, everything i know is from straight up experience from working on my 1988 rs 1989 IROC-Z andreading blogs mags and other websites. (this is a little off subject but its explaining why im asking this question...i am buying a 2002 Z-28 with an ls-1 and a six speed while im out here in iraq. as soon as i get home it will be waiting for me andim taking the money i saved out here and dropping it into the car.) I dont quite understand what you meant by the stock compression ratio being 10.3:1... Would that mean 10.3 ci of air is turned into1 ci of air when the cylinder hits top dead center, or am i way off with that and its somthing totally different.

with my question. I fgured an ls-1 motor can only handle so many pounds per square inch in one cylinder before stuff starts coming apart... right? my question was... When an ls-1 motor is running stock, on average howmany pounds per square inch is the motor creating in each cylinder? and... How many pounds persquare inch can one cylinder handle before things start breaking?

im sorry my un-educated mouth was not being clear. i tried to revise it the best i could thank you foryourhelp

 

thats exactly what it means.

the 8psi that slvr cited is manifold pressure, so this is pressure above what the motor does on its own i.e. you take ambient pressure (take it to be zero even though it isnt, but i dont knwo what 1 atm is in psi..... so just roll w me here) and you compress it down by a factor of 10.3. so now you put on the turbo and when the piston is at its lowest point there is already a pressure of 8psi in the chamber. you then compress it by a factor of 10.3 again. PV=nRT, so PV(1)=PV(2) 8psi*10.3relative volumes = x psi * 1 relative volume so max pressure is 82.4psi. P/T(1)=P/T(2) so 8psi/1 relative temperature unit = 82.4psi / x relative pressure units. OR 8psi/82.4psi = 1 relative pressure unit / x relative units = .097 1/.097 = is again.... 10.3 (this is where i suddenly realize i didnt need the first half of this to make my point.....) basically pressure is not your enemy, but pressure and temperature vary directly with each other. temperature rises as pressure rises, pressure rises as volume drops. So what is essentially happening: as you drive the piston upward you increase temperature AND pressure, each comprising a total factor of 10.3. if pressure was held constant you would multiply temps by 10.3, if temp held constant you would multiply pressure by 10.3, but since neither is held constant they share the effect, and (i believe) both end up raising by the square root of 10.3 which is 3.2.


im tired.... (been at the library doing chem reports all day....) let me start from there....

temps and pressure both increase by a factor of 3.2 in the ls1 engine. atmospheric pressure is 14.6 psi, so you are in reality boosting 22.6psi @ a measured 8 psi.

you have to propagate the heat transfer in your engine. so you go from 14.6 to 22.6psi from the turbo to your engine (not including any heat picked up from the friction of the turbo) well say 70 degrees is ambient. 22.6/(14.6/70)=108.4 degrees after the turbo. you then compress it in the motor, and since pressure and temperature both share the load by the equation pv/t=pv/t. you then multiply 108.4*3.2=346 where non turbo cars would be 70*3.2=224. the higher your temps the more likely you are to have detonation and turd your motor

 

ill come through and check all that in the morning...... my eyes are getting blurry and there may be a chance i missed something in the theory.

but this is why intercoolers are important. if you follow the relationships, any difference from abient after the turbo gets multiplied as well. a small difference in the intake becomes a larger difference in the chamber

 

i understand what your saying it just needed to be explained to me. i have an older brother who is a mechanical engineer and you sounded exactly like him lo... what are you going to school for because it sounds like you have a very high iq when it comes to physics and mathematics!

 

I am a chemistry major. basically the nutshell lecture is that every degree you raise in the manifold is multiplied in the chamber. high temps = bad

 

does anyone on this forum actually have a turbocharged ls1? I see these threads all the time, "should i turbocharge my z28??" or "supercharging my camaro?" Not to be a jerk or anything, but i'm starting to feel like these are just attention threads as I haven't really seen any of these people come back with a turbo/sc car....

 

I understand where your coming from people do alot of talking but they know they cant ever afford a 5000 turbo system for their car, i on the other hand am deployed coming home with 15000 to work with and a 5000 system for my car would only be a 3rd of my deployment money and i plan on putting the other 10 into retirement.

 

Many of them are attention threads, that said, Meatwad has some legitimate questions that could be beneficial to the rest of the community later down the road, so thus far the thread is productive.