Boost Question

[MrJohnWayne]

Lets see if someone can shine some light on this for me.

2000 f350 7.3 PSD (mods in sig) 188K on the clock. I made a diy boost fooler with a simple pressure reg that internally bleeds downstream. It does work havn't seen a SES light since. Unplugged my waste gate, and even with the 6.0 IC I cannot get over 25 psi of boost. Have checked for leaks. I'm thinking maybe the turbo is giving out. Starting to surge alot when towing but only in OD.

Let me hear some opinions....

Thanks,

[CSIPSD]

25 doesnt sound bad... Might check your boost with a AE program... Might be a boost gauge issue or the line too.

[Dave]

25 is decent for a chipped SD with the stock turbo

[MrJohnWayne]

Yeah I know it isnt bad but I could swear unless I didnt fully understand that i've seen people on stock turbos (no ww etc..) getting 30+ psi even though it's bad for it. Maybe i'm crazy.

[CSIPSD]

Some trucks do some dont... I could not get over 25-27 and still put down 326 hp before the turbo and injectors... With a DI chip. Now with injectors and such I see 38psi...

Got to remember that boost doesnt equal more power, just more heat. If your not smoking, EGT's are good, and the power is there I would bet your doing fine... I also changed the Boost gauge from a Autocrap to a Isspro and picked up about 3PSI...

[Dave]

Ive never seen over 26 psi out of mine and that was on the pedal real hard to pass a big rig

[gcop]

hey John, where is your boost gauge tapped? And the DIY boost fooler, is it in the MAP line?

[CSIPSD]

Originally Posted by gcop

hey John, where is your boost gauge tapped? And the DIY boost fooler, is it in the MAP line?

I have one at each location... both read about the same, with in a # or so...

[MrJohnWayne]

My egt's are ok. When I unplugged the wastegate i went from 23 psi to 25-26 and dropped the egt's at wot a little. Now I still hit 1300+ but not as fast.

Yes my fooler is in the map line with my boost gauge. And yes the tap for the gauge is before the regulator

[ABOBB]

Originally Posted by CSIPSD

Some trucks do some dont... I could not get over 25-27 and still put down 326 hp before the turbo and injectors... With a DI chip. Now with injectors and such I see 38psi...

Got to remember that boost doesnt equal more power, just more heat. If your not smoking, EGT's are good, and the power is there I would bet your doing fine... I also changed the Boost gauge from a Autocrap to a Isspro and picked up about 3PSI...

Actually.... more boost generally means more restriction. Whether or not it means more heat depends a lot on where in the turbo's map range you are.

John... I would expect the 6.0 IC to actually lower you boost, not raise it. That doesn not mean that performance will not increase. The IC swap gives you less restriction accross the cooler (which means less boost) and also cools the charge air better (which again potentially means less boost). The cooler air is denser, and shows a lower pressure, but most likely delivers just as much (if not more) oxygen as the warmer charge air at a higher pressure.