How much boost on stock internals
The stock turbo isn't going to hold 30psi very long but it will make it very quickly and thus tuning in that RPM range is critical. If you are running high quality fuel you probably don't have much to worry about but if you are cheap skating then I wouldn't be aiming for 30psi.
On my 9 26psi is safely reached on 100 octane and modest tune. That was good for 116mph traps. Cranking the boost up much higher didn't really provide much of a return at that track.
As for head studs. I wouldn't recommend doing them at all. There's nothing that shows the stock hardware is problematic. Most head gasket problems were caused by a **** poor tune (KNOCK) or dicking with head studs using the 1x1 method. There are tons of folks running high boost on stock hardware without issue. The key is the tune. Running 30 psi on meth with garage tune is asking for trouble.
If you are dyno'ing.... dump some C/Q16 in the tank and make a 30psi pass. Then turn the boost down to 26psi and make another pass. You will be surprized at how little the added boost does for you. In fact most people see gains by spking boost because it broadens the powerband .... however if you use ECU based boost control you really don't need to spike boost. Increasing the wastegate duty cycle will provide nearly the same returns.
On my 9 26psi is safely reached on 100 octane and modest tune. That was good for 116mph traps. Cranking the boost up much higher didn't really provide much of a return at that track.
As for head studs. I wouldn't recommend doing them at all. There's nothing that shows the stock hardware is problematic. Most head gasket problems were caused by a **** poor tune (KNOCK) or dicking with head studs using the 1x1 method. There are tons of folks running high boost on stock hardware without issue. The key is the tune. Running 30 psi on meth with garage tune is asking for trouble.
If you are dyno'ing.... dump some C/Q16 in the tank and make a 30psi pass. Then turn the boost down to 26psi and make another pass. You will be surprized at how little the added boost does for you. In fact most people see gains by spking boost because it broadens the powerband .... however if you use ECU based boost control you really don't need to spike boost. Increasing the wastegate duty cycle will provide nearly the same returns.
head studs are a huge waste of money.... people go back and forth about it.... you can search on here and find more information than you ever want to know about head studs.....however, if you ever have to take the head off for any reason, then replace the head bolts with head studs........
head studs are a huge waste of money.... people go back and forth about it.... you can search on here and find more information than you ever want to know about head studs.....however, if you ever have to take the head off for any reason, then replace the head bolts with head studs........
Like I said I had a friend recently with a head lifting problem due to HEADSTUDS
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Joined: Sep 2006
Posts: 761
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From: East Hampton Ct.
I run a Evo 8 in NASA's Super Touring 2 series, 370whp/415ftlbs with a 9 turbo, 650 injectors, head studs, Cosworth 272 cams, Sunoco 100 and 25lbs boost for a 40 minute race - no problems...
