I just installed a pyrometer and a boost gauge in my truck, and under full throttle im only getting about 21 psi. I was really hoping for more seeings how i added a 16cm housing, 4" exhaust, and a K&N filter with the pump adjustment.

Is this about normal for my setup or did i pinch the air hose a little somewhere in instalation? I really dont want to have to take off the a pillar mount (it was a pain to get on in the first place).

Just like to know what your trucks run for boost.....

 

Does your gauge hold boost while you cruise and accelerate, or does it drop quickley to 0 after you accelerate? Yuo might try losing your air filter housing, turning you fuel pin. How much did you adjust the pump.... past the lock collar?

 

I get 26 lbs. out of my '93. I dont know what has been done to my truck yet because I have only had it for about 2 months. Plus when I get over about 15-20 psi the clutch slipps somethin feirce .

 

Like redleg said, If your gauge sweeps to 21 under a load and sweeps back when your off the throttle than it is probably OK. I believe when mine had a 16 CM and the fuel screw in I got a max of 23 PSI.
Put some nozzles in and you will see lots more power and boost Last night I hit 40 PSI for the first time
Enjoy bombing
Frosty

 

Best I've hit with mine is 17lbs...no load on the best hill we have around here.

 

Best I've hit with mine is 17lbs...no load on the best hill we have around here. Stock pump settings.

 

With the stock housing I was running about 24 max PSI at full speed (about 2900 RPM in 5th). With the 12cm I am hitting the 25 mark down around 2200 and getting about 27-28psi full speed boost.

Those numbers sound right without any adjustments to the governor settings or the AFC cone washer shave. I had 21 psi for the longest time till I opened up the governor and shaved the pin washer.

Timing also has an affect on boost, if you have stock timing that number still sounds good.

J-eh

 

I have removed the retaining collar on the pump all together because it was getting in the way, and i actually turned the pump down from where it was when i first turned it up. In college and need to save any money i can... It stays at about 5 psi when im cruising, and when i let off after accelerating it drops straight to zero. Im thinking i may have overtighened the lock collar on the gauge side and pinched the line a little. Maybe not.....

 

it sounds about rite to me i'm runing about the same as you up hear in the thin air


and by the way if you ask any one who dont own a cummins they will tell ya that we ar not normal anyhow