nrussell

Yeah, I know. I planned and bought all these parts, for him to install, while I was away on vacation, which I still am, and the plan has been DERAILED. I guess I need to find someone else who wants my money to install these parts.

RUNONGREASE

Any way I could see your MPI? I want to see how much room it will take up.

soulezoo

I just hit 80 psi today for the first time... WOW! Glad I have studs at least...

Spooler

No pics of those ball bearing babies??????? They should spool and sound wonderful.......

jrussell

Sure. Send me a PM and we can exchange phone numbers.

soulezoo

They do spool and sound wonderful.. see twin club thread for more details... I cannot post pics yet due to some contract concerns that I am obligated to honor.

blwnsmke

Well Ill be putting a 62 over s400 with stock head bolts for now. Would it just be extra insurance to run the two blow offs? If you didn't run them, when would the turbos stop spooling? Whenever they can't move any more air?

jrussell

Stock head bolts = pop-off valves needed

Turbos spool according to how much fuel is pushing them. Your fueling determines the max boost (unless you have pop-off valves).

Billy Ram

I believe Jeff is wanting to make sure your motor is going to be reliable with the cam and other mods. You need to keep a certain amount of clearence between the valves and the pistons. With a higher lift cam the clearence is going to be less if you don't don't cut the pistons. With the softwares that raise the rpms I wouldn't want to take chances with something as expensive as your motor. Jeff just wants you to do it right and not have problems down the road.

abc4yew

I am 100% sure that with the F1 springs, cam and ARP's you would not have to fly cut the pistons unless you have a Helix 3. I ran up to 90psi boost with the above components for 20k miles and over 60 1/4 miles and no contact was made...Big thing to watch is to constantly check valve lash...If you see a valve out of tolerance by much it might be bent or the seat out of place...I wouldn't o-ring....that's 12 valve stuff....fire ring if you are going to spend much time over 75psi and you don't want to constantly check the head stud torque....If you properly torque the headstud nuts and check them as often as you check the valve lash ....then you don't need fire rings...this is proven. I didn't check valve lash one week and sure enough a valve dropped and took out a piston and ring and blew the pieces of ring to between the twins...learn from my hard lessons. Kerry

Don M

The Helix 2 cam has more clearance on the intake and exhaust sides than a stock cam at and near top dead center. When you start a cam grind with a new billet you can put the lobes anywhere you want without the limitations the stock regrinds have.

He will actually have more room between the pistons and valves than it came with from the factory in stock form.

I hope this helps some. ( -;

blwnsmke

Whats the highest you can set the blow off valves at? I guess either way they are not a bad thing to have for a little extra insurance.. You think stock bolts and 55-60psi would be safe?

cincydiesel

50 psi is about it for stock bolts. I would think anything higher would be flirting with a towtruck