HDJ81 Boost levels (1 Viewer)

[SamB]

Hay, over the weekend I installed a boost gauge in my 92 HDJ81, the max boost it is running is 11psi, according to the manual stock boost is 7-9psi. As far as I know everything is standard.

I was wondering if anyone else had a boost gauge installed and what boost levels they were getting and with what levels of modifications??

The next step is to put a big exhaust on and intercooler, I have a pyro to put in when the exhaust is done, and then more boost and maybe fuel!!

 

[crushers]

14 psi for 2 of the ones i tested...

 

[Tapage]

97 1HD-T totally overhauled .. ( friend ) no more than 9 PSI yet ..

 

[jcolvin]

My 91 HD-T maxes out at 11 psi. I read somewhere (can't remember) that the 91-92's max out at 11 and the later ones at 9....but don't quote me. If Wayne's getting 14 they must have had the wastegate actuator fiddled with.....

 

[hdj105]

Hay, over the weekend I installed a boost gauge in my 92 HDJ81, the max boost it is running is 11psi, according to the manual stock boost is 7-9psi. As far as I know everything is standard.

11 psi sounds pretty normal in my experience. Asking much more of the original CT26 will see it out of it's efficiency envelope and any gains will be minimal. My old intercooled 1HD-T used to peak about 12.5psi.

The figure quoted in the FSM is based on the vehicle in neutral with the throttle wide open, which will yield different results to having the engine under full load (i.e. driving).

 

[Tapage]

The figure quoted in the FSM is based on the vehicle in neutral with the throttle wide open, which will yield different results to having the engine under full load (i.e. driving).

It make pretty sence to me .. under heavy load you get maybe more boost .. at max at wastegate can hold ..