2T0neTC

I currently have a custom piping and exhaust manifold setup but I wanna know how much boost a 2005 scion tc engine with 71k miles will hold. Looking to put 50mm wastegate and 12 psi. Currently at 8PSI Don't worry about traction, I got brand new NT555's all around. Car slips a little if I launch like an evo and second gear BARLEY slips with cold tires and doesn't slip at all when warmed up. Car will most likely be street tuned and not being tuned at UMS! They suck!

Under the hood and current setup:

criminaltc

10lbs.

paul_dezod

Depends on how well it's tuned, how it's driven and maintained. Usually I say 325-350whp is the danger zone for a stock block.

Carlanga

Paul is right on the dot. I say once you go past 310whp even on a good tune it becomes a ticking bomb. Eventually a rod is going to give, I got two engines to prove it :-( My tC is currently sitting in the garage waiting for funds to get a long or short block depending on the head condition and build it up. Aiming for 500whp

2T0neTC

So get forged rods and pistons and car will be good for 12+ psi? Or does it needs valves too? Maybe it will be a transbreaker :p

criminaltc

Pistons and rods will suffice for 500+hp on whatever boost, well over 12+ that's for sure, just as long as compression is 9:1 or close that way it's safe. Just building bottom end is fine. Although you don't need to build the head, the head should be machined and completely cleaned with a valve job and valve guides and bowl work. And yes, 500+ is a trans breaker. Ask Black Knight.

2T0neTC

I need to fix my trans anyways. I wanna change final drive ALOT, and gears are starting to grind like crazy if you're doing any kinds of racing/w downshifts. 1st grinds if I'm going over 12mph and third grinds like half the time. Might be because my clutch is still engaging SLIGHTLY even though it's to the floor. I might just do that. rebuild trans and change final drive with forged rods and pistons.

criminaltc

Why on earth would you put it in first at 12mph? Stock first gear shouldn't even have it put in unless you're stopped. Of course it's going to grind. It should be locking you out actually, so you really must be jamming it in there. I would advise against that.

2T0neTC

I'm pretty sure mine is just messed up :l I drove my brother's cobalt ss recently. my jesus, it is soo easy to drive compared to mine. Very light clutch pedal and easy smooth steering.

criminaltc

Yeah.

paul_dezod

GM actually did a real good job on the Cobalts. Factory turbo will always be better than N/A-T. Night and day. However, with N/A-T, you get the satisfaction of "built not bought"

2T0neTC

Have you even watched TFATF? The built not bought is saying it's better to have a lower end car with a built engine and transmission than it is to buy a lambo or ferrari that comes stock 500 hp.

burgandybomber

iTrader: (1)

I am playing around in the 7-9 psi range right now (a little under 4k miles) till I get new tires. Which speaking of tires, what size are you running? I cant find anything for a 17 that would fit in the NT555's. Looking at the Continental Extreme Contact DW right now because I was very satisfied with the DWS when it was stock. I really want the Michelin Pilot Sport's but the 140 dollar savings can buy more stuff lol.

Its an absurdly nice little car for the Big Bowtie to have made, but there is one thing that you can never change. Its still a Cobalt...

The expression you get from cars that cost twice as much are twice as nice lol. Youll usually see or maybe , and sometimes .

2T0neTC

I think the smallest you can get NT555's is 18 inch. i'm running 225/40/18 all around in some Axis rims. My rears still have the little nipple things sticking out they're so new. The only time I spin is when I'm on less than half a tank.

criminaltc

Dude, did you even read what Paul wrote? He was completely agreeing with you in that factory turbo (ie the cobalt you love so much) is better than taking an N/A motor and making it turbo, which is 100% true. And all he was saying about built not bought is the satisfaction of knowing and feeling good about the drastic modifications you've made to your car. You can't feel that way about the cobalt if you leave it at as is. And that fact that you felt you had to bring ferrari's into the conversation is just sad...

What up Burgandy!! Where you been homie! Bump your thread and let's see what's going on!

tom0613

iTrader: (2)

just keep it at 8 psi until u build the bottom end. your going to break SH*t on the stock long block. and you can talk to dezod and ptunning for all your power need these guys have everything u need.

burgandybomber

iTrader: (1)

Im working on some things... hopefully I get my tax return soon and then the parts will flow lol.

criminaltc

Cool guy smirk. I love it.