Hey starion turbo guys! My newly built truck takes forever to spool. It has a 12a with a higher lift cam (not sure of grind, but still hyd) and doesn't go into positive pressure till around 3,700 -4,000. It is not tuned yet as my new aem wideband was junk. I am sure that will help but I am starting to regret this build. What can I do? What reasonably priced turbo will spool at a lower Rpm? Is my turbo just junk? Spins freely and has no shaft play. Thanks guys

My Mighty Max has a stock engine rebuild minus balance shafts. I'm reasonably sure it has the 12Aturbo, as well. However, it builds boost beginning about 2500 rpm. Despite that, the boost stays less than 4 psi until about 3500 rpm, then goes to the 10 psi wastegate quickly. The gent who assembled my truck as his project of love said the truck liked to operate in the 5000 rpm area, which I feel no need to subject the engine to for many periods of time.

My truck presently is without an intercooler, uses the stock precat after the turbo, and has 2 1/2" exhaust pipe and Magnaflow muffler.

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I need to replace the head gasket, install my 'new' "Mitsubishi" valve cover from PowerRam50, clean up the engine bay and get rid of the yucky yellow failure paint the PO liked, refit the AC belt tensioner, and find a wide low-profile IC that fits behind the aluminum skid plate under the bumper...then return this truck to DD status.

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Sounds like maybe you need to adjust your wastegate preload. it is 8mm of preload for the diesel, not sure about gas

Thank You, I definitely need to adjust the wastegate. It was binding and after straitening I didn't adjust before i reinstalled. Hope it works

That's way too slow. Mine spooled to 7psi by 2500. I think the wastegate is leaking, or something is binding the turbo shaft. The 12a is sort of small and very responsive on a 2.6. One of the beauties of this system is the snappy response when right.

I'd unhook the sctuator, after you mark where the arm on the wastegate is situated. Then see if the arm will move in the closing direction.

There is definitely something wrong somewhere if you're getting boost that late. Have you checked for boost leaks? What kind of exhaust system and downpipe do you have?

It was the Wastegate preload!!! Runs way better. Now for tuning. Thanks guys