Once I get the good engine in the truck I'll see how the turbo behaves and decide then to change the turbine housing. The early (pre'06) head exhaust ports are REALLY restrictive. With the built engine the exhaust ports ( after porting on the '06 head) flow > 210 cfm @ 28" at 0.450 lift. My guess is almost 50% more than the early head. So this should help get the turbo to spool up faster.
Now,,,, don't take offence here but,,,,,,
*No problem advice even if incorrect is better than silence...
First off, with that big of an exhaust housing you will need @ least a 3500 Stall converter,BTW what does your stall to?
*With the stock 4200 1800 rpm, with the previous 292 2300 rpm. I'll see how it reacts with the built engine before making a change. But generally agree that at least a 3000 stall converter will help. I am still leaning towards 3500 to get great spool up. What are your rear brakes disc?
* 11" Drum, I ran out of time to go in and readjust the brakes up - so this will go on the maintainence list... ***If you can upgrade to larger wheel cylinders it will help hold the truck when trying to boost launch.A trans brake would help holding the car,but if you have a low stall converter it will never spool up fast.
Yep .. running a 4L60e so no sure if its a good idea... ***I would not install a trans brake in that trans I am just wondering why you have such a large turbine housing? Is it a drag car/truck only?
I got a screaming deal on the the turbo - $<900! for a new Garrett Gt4088. So I figure if I need a smaller housing it won't cost as much as getting the *right* turbo. The local turbo shop said they would give me a credit against a smaller housing if I need it. What size/trim is your turbine wheel? Check the Garrett site P/N 703457-2. This is a non ball bearing turbo correct? GTR's are ball bearing IIRC. ***That is a good sized turbo,the turbine housing is a bit big but, that also depends on your goals. Like you said, a looser converter will help.Sorry if I sound harsh,I just want to see you run fast. << me too. Good luck!!
