the T4 1.10 ar 83mm turbine wheel. does any one think that will have backpressure issues at 23 lbs?

 

I also wouldn't consider anything above 15 psi or so on pump fuel+meth. E85 an option for you?

If you are looking to maximize your combo I would be running a t6 turbo. With a 1.1 t4 you will see some back pressure but heads lifting will be a problem before that boost number. To me, it still sounds like you could reach your goals on a production block with tfs heads.

 

so 93 and pump gas, ill be limited to 15psi?
so you think the heads will lift be for i see back pressure issues?

 

Alot of these questions depend on the answer to the others. I am just saying anything over 15 psi or so and I would reccomend using good gas, meth is good for getting a few more psi out of the same combo but I wouldn't lean hard on anything while relying on it for octane.

Back pressure isnt one of those things that starts at a certain psi and becomes a instant problem. Turbo sizing is always a trade off...spool time vs hp. A smaller turbo will spool quicker, have more back pressure, and make less hp lb for lb(efficency come into play as well). Going with a well matched turbo and kit will go a ways in helping keep the combination happy.

As far as the heads lifting I have ran stock blocks and stock heads into the 800- 900 rwhp range without ever really lifting a head. I have taken a few apart that began to seep alittle at the bottom of the cylinder but never pressurized the coolant system.

 

im not really worried about the heads lifting. with ls9 gaskets, arp studs, and tfs heads i think they will stay down.

i am going up grade to a 87mm exhaust wheel. that will help reduce bp. ive seen this turbo make 1k flywheel as it sits now. but dont know what the bp was. but i feel like the bigger wheel will let me get 1050-1100 easyer