hi guys, I´m new in yotatech. I just get a 98 tacoma 4x4 xcab with the 3.4 L trd supercharged with a urd 2.22 in pulley, headers, 265/75R16 BFG KM2, automatic, and a unichip suppost to be set for this speccs, I´m getting 4 pound of boost, is there something in the set up or the valve in the back of the supercharger to gain more boost? I´ll thank any help.

 

I get 6 pounds of boost on mine with the stock 2.2 pully. I belive I can get 8 if I go to a 2in pully. Also have a coolingmist water methonal injection kit on it that makes a noticable differance in power. Just somethin to think about... I havent had mine but about 5 months so im still playin with everything and figuring out what to do next. Really quick for a 4WD truck and lots of fun.

 

Is your s/c black or grey??

 

Correction of first post, The stock pully is 2.5. The aftermarket is 2.2.

 

thanks a lot Dmiller. my SC its gray, I think I should get more boost cuz I have a 2.7 black S/C on my wife´s 98 4runner and I get 4 pounds with stock everything.
and is not a big difference in how power feels in both.

 

how are you getting a 2.7 diameter? factory pulley was a 2.3. I know they later started using a bigger pulley to fight the high gear low rpm ping. But with my 2.3 pulley i was getting 6.5 psi boost. 2.2 pulley i was getting 7.5 and with the 2.1 I was getting up to 10 psi boost.
The valve at the back is the idle bypass valve. If it leaks, you can loose boost. However, headers can drop your boost as well.

 

VITAL 22RE I MEANT 2.7 LITERS NOT THE PULLEY. THAT ONE IN THE 4RUNNER IS THE STOCK PULLEY. BUT WHAT WOULD YOU SUGGEST ME TO CHECK ON THE TACOMA BESIDES LEAKS. BUT KNOW THAT U MENTION EXHAUST. THIS HAS LIKE A 2 1/2 " PIPING WITH A CRAPPY 2010 FORD RAPTOR MUFFLER. (dont laugh at me. IT CAME WITH THE TRUCK)

 

Boost can leak at the injectors seals, lower manifold gaskets to head, lower manifold gasket to sc. The old grey sc had boost leaks at the idle bypass valve. Sometimes you can have leaks in the line up to the boost gauge and that could give a lower reading. How many miles on the sc? sometimes they get old and just need to be rebuilt. Most boost loss when dealing with exuast is gonna be from headers. There is nothing wrong with that, its just means you have less back pressure due to higher flowing exhuast. A high flow cat and muffler aren't gonna give you nearly as low of a reading as the headers would.

 

All this nonsense about headers and leaks and blah blah when the belt is just slippin on the pulley. Buy a new belt, tighten it. bingo.

 

All are possible.

On my truck I had them ALL. I had to fix them 1 by 1 picking up .5 psi here and there. till i finally got the ~10-10.5psi i am running now.

Build yourself a boost leak tester and go to town. Also pull the bypass valve off and see if it has a gap like mine. Replacing the belt is also a good idea. If you don't already upgrading to the dynamic tensioner is not a bad idea either.