boost and stock interals

[Black Knight 00]

i was wondering what can the stock 4g63 take as far as boost levels? cuz someone told me that if i run with pistons rings and gaskets i should be able to run at 17 psi all day long. thanks for the input guys and gals

[Blackcrow64]

Um, most of us run 17psi daily... The stock internals should handle up to about 400-450hp before needing to be upgraded. The amount of boost you run isn't the thing to be worrying about on your pistons and such. You will blow a head gasket way before having to worry about anything else. Heck, I think some people are running 25-30psi when they take em out to the track. Of course using race fuel too... Take a look around and do some reading up on the subject of boosting.

[blk_srt]

You can run 20-25psi all day with the right mods with no problem even more if you know what your doing

[Talon69]

Yup like they said the right mods!! If you plan on running over 20 psi you better get arp studs and a 4 layer metal HG or one of your choice but not stock.

[Black Knight 00]

thanks for the help once again. i made a new thread to see just what everyone thinks the "right mods" are

[Thor06]

I am going to have to stay with Kevin on this, go composite as long as you can and get ARP's. Knock will eat a composite gasket far before high boost pressures will.

[kjewer1]

Yup, me and most of the fast locals are running stock gaskets and over 30 psi. I have however toasted motors before blowing the stock gasket. My last motor in the 2g I was at 29 psi, 64 lbs/min, and motoring my way down the track to a 11.3 at 126 when the motor let go. The HG held until the head finally lifted because I knew it was a quick pass and was not going to let off when the motor started to fail When the head lifted the pressure shot the front water pipe clean out of the pump. But, the point is that the stock HG will hold up to the power. Eventually the 255 being a pussy and leaning me out to 13.5:1 took out 3 plugs and pistons before the gasket went. ARPs properly installed are the key to making it work, as well as good tuning. Excessive knock or ridiculous amounts of timing will take out nearly any HG.

The main advantage to using a stock HG is that it will seal on nearly any surface. The Cometic and other metal gaskets are finicky about surface flatness and finish RA. People are popping these things at 20 psi on shake down passes if the block and head aren't cut to a smooth enough finish, and not all shops can or will do it. Stock gaskets are also cheap. If one blows you're out 40 bucks and 90 minutes of your time.

And to reiterate what has already been said, you can not measure the strength of the motor or any other part by boost pressure alone. Boost is airflow that you are NOT using

[Thor06]

I also have to add that I used a OEM metal one and a composite one. The composite was like 30% of the price and sealed much better. I was runninf 130 across on the metal one, it was over 140 with the composite.