Am I risking stretching the stock head bolts with a 27psi spike 110octane tune or should I not worry about it? I was contemplating doing a 110oct tune @26psi but I figured why not 27.

 

If i were you i would install headstuds, they're cheap insurance when running 24+ psi.

 

i just installed my APR Headstuds this morning when i was installing my Mivec S1 Cams. i'm only gonna be running 22 psi on 91 octane, but i heard that you run the risk of stretching the stock headstuds when running any boost over stock. and for $90 it was a no brainer.

 

your call....

but do some reading first,

https://www.evolutionm.net/forums/sh...d.php?t=305932

 

You'll be fine. Just make sure your tune is spot on.

 

I wish Mixmastermike didn't post that thread, now every noob's gonna think they need head studs...

 

You will be fine on the stock headbolts. I have been running 30psi since march on mine. And I have even spiked up to 36psi.

 

boost doesnts cause stretching of the stock head bolts, its when u have detonation, thats when ur head lifts.

 

look at my sig... im on stockers at 27psi..but i keep the boost down to 23 most of the time and dont beat on the car

 

X2....my Race gas tune,spikes 28psi and hold 27.my stockers are doing just fine

 

going 150mph on 120 mph rated tires wont cause a blow out, its if the temperature gets to high will the blowout happen.
***its better to be safe and buy the 160mph rated tires!!!!!!!!!******

 

I think i'm gonna buy Z rated tires. I never drive over 120, and stay under 90 99% of the time. *But i'll do it for protection*

 

its a cheap investment that can save you hundreds of dollars down the road so my advice to you would be to get the arp headstuds. theyre easy to install and well worth every penny.

 

we have a evo 8 with a 32psi spike and falling to 26psi, it has been doing this for over 2 years and over 25k miles! no problems.

 

I am spiking @ 33PSI stock head bolts for about a year now no problems.