psi is psi is psi. PSI means nothing. Cant stress that enough.
Power is what determines what is safe for an engine. Every engine will respond a little differently than another and make more/less power than another.
I believe the actual structural failure point of the stock rods is in the mid 600's to 700awhp or so when Trevor finally just straight up SNAPPED a stock rod. Which id like to add, is an absolute staggering amount of power and would likely scare you senseless pending your experience with fast cars.
back pressure is also another concern imo which could be why a lot of people with smaller turbos making big power run into head lift problems where-as Matt was running mid 30's boost level and making over 1k wheel hp and not lifting his heads since he was running properly large turbos. Just a theory of mine.
18g's while sound different and cool, are no better than a E3 16g. If you need more power than a 16g can dish out, like Chris has suggested, step up to the 50 trims or just screw off with the little TD05 based kits and speak with Matt about what setup he would recommend for your car.
Jason
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3000GT VR4 = It's a brilliant wreckage of ingenious bad ideas...
So then the PSI is only concerning the turbo's safety itself? Running 26 PSI in a stock engine won't hurt it at all? I was thinking of doing 20 PSI from the TD05 18Gs...
If your looking for a safe psi number, for the 3000gt its about 15psi. Run better heads, intercooler, bigger turbos, and the amount of HP you make at this psi number will vary but usually with 93 octane, your running into detonation above 15psi. Like Jason said, thats just a number measuring backpressure at the intake. Cars like EVOs typically run about 19psi peak but then it drops at higher rpms and I have to think that with proper tuning (manipulating timing) and careful modding, we could see that also on pump gas. My feeling is that since most highly modded cars need at least 19psi to reach 500awhp, thats about the limit most people should aim for on pump gas (500awhp, not the psi)
Now, if your looking for a safe race gas psi, that number has been typically 30psi. Anything higher and you risk blowing headgaskets and overheating and less then that with the right fuel and tuning, the car will make anywhere from the 500awhp at 20psi to almost 1000awhp if your running a stroker and one of the bad boy bigger turbo setups, but on a stock motor/heads your probably not going to make more then 700awhp at 30psi, and thats pretty much where the motors reached its safety limits anyway.
Forget about that power level on pump gas. There are people that have thrown everything at the car including a stroker and havn't managed to get more then 550awhp on pump fuel only. Even 500awhp on pump fuel is a difficult task. If your running pump only, then the stock short block is enough for you as long as your not knocking. Run some methanol injection and you can reach 500awhp safely on a stock motor on 93 octane.
Sam
Yes indeed Sam! That seems pretty hard!
Since a month or two I'm trying to figure if I'll go for DR750 or for a DBB800 kit! Now that the result of the 750's are begin to be shown I'm still not fully decided, but leaning toward DBB800 a little more for the moment...
But if we look at eyekndy result with his DR-800 : 476AWHP and 415AWTQ on pump gas 93 @ 20psi with stock heads, cams and block. It could/should be somewhere around 500-550WHP with water-meth and DR stage 3 heads (which I have both).
550-575WHP is what I was aiming for, I was no more sure it was a good idea when Chris told me he recommend to stay around 500WHP for safety mesure. But in another hand I know tuners are usually very prudent with anyone's car (but their)! They preffer to be on safe side more then on the edge in case something bad happend. Let say I'm aiming for 500-550WHP now.
Like I said with the result of eyekndy, I'm pretty sure the DR DB800 with water/meth and DR Stage 3 heads could lead to that on pump!
Now I would be curious to know how much WHP the DR750 would give with those same mods on pump and a 3.0l! Any idea Matt ? (I know it's only speculation)!
On the shelf : Denso 660cc, 3SX poly mounts, 3SX cam gears, SCE racing oil pan, South Bend stage 4 FE clutch... and some other nice toys are comming soon.
PSI is a measure of restriction not of power or CFM the engine is moving through itself.
500AWHP on pump gas, that is going to be your safe limit.
-Chris
I have a friend who knows quite a bit about cars and such. He built his Cobalt from scratch. He claims PSI has everything to do with how the engine will handle.
For instance, his stock engine blew up from too much PSI from the supercharger.
So if I want 500 AWHP on pump gas, I will be safe from engine internal upgrades? And no matter how much boost I run it won't effect the engines stock internals?
I'm just thoroughly confused, sorry for the repetitive questions.
Like I said in an earlier post, it's not the PSI that kill the engine... yes if you run too much PSI it will kill the engine, not because there is a magic number you have to respect, but because too much PSI will lead to knock and/or lean condition. Those are the engine's killers... you have to tune and log your car to see where is the maximum PSI you can run before it began to knock (pre-detonation) and be sure to have an adequate fuel set-up/octane to be sure not to lean.
Let say you begin to see knock at 18psi in your set-up, if you want to run more boost you can add a water/meth injection system and run a few more PSI, or you can put some race gas to raise your octane (will raise the resistance to knock) in your tank occasionnaly to go at the track for example.
I have a friend who knows quite a bit about cars and such. He built his Cobalt from scratch. He claims PSI has everything to do with how the engine will handle.
For instance, his stock engine blew up from too much PSI from the supercharger.
So if I want 500 AWHP on pump gas, I will be safe from engine internal upgrades? And no matter how much boost I run it won't effect the engines stock internals?
I'm just thoroughly confused, sorry for the repetitive questions.
Thanks for all the help thus far.
-Kurt
Cobalt+SS+Engine+(drmbldr)Tell you're friend it has to do with CFM which is a derivitave of displacement, RPM, demand lines, and V.E. and also let him know a stock Ecotec can't move more than 500 CFM before exploding. Which would be 15psi at 7000RPM's or 20 psi at 6500. It has nothing to do with psi It has to do with how much air it can take on the strokes. You can tune for psi but the psi isn't what killed it was the CFM or the heat. You start squeezing any tighter than 500CFM on that dandy little stock direct inject GM 2.0L and kaboom!
Anyway, good topic, I'd like to see a 3/S 550 or more on pump with 0 adders. (can you say kachinggg). For 550 on pump isn't it like 10 grand cheaper to do a 350 small block swap?
That's a pretty cool video. You basically described what happened to his car to the exact inch. He blamed it on the PSI though... I trust what he says to a certain point because he does know his shit. But if it's not the PSI that killed him, I believe this huge community of experienced 3/S owners.
I think I'm going to go with the TD05 16g Evo III turbo kit from 3sx.com and take that as far as it will go safely, and whatever horsepower I'm at there is where I'm at. Then maybe upgrade more as I get more $$ =p.
Be careful about certain types of manifolds on the rear bank as I have been personal witness to over (6) 3/S that've cracked custom manifold welds and lets just say they didn't come from E-Bay, Canada, or China.
Be careful about certain types of manifolds on the rear bank as I have been personal witness to over (6) 3/S that've cracked custom manifold welds and lets just say they didn't come from E-Bay, Canada, or China.
Well, lets say where they did come from so we know.
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Re: Realistic goal 550 HP; parts needed?
