[Krogg]

I have a full service matco determinator scan tool, I was going over my truck the other day and decided to road test it, every thing checks out but my boost! it seams low 19.8 was the highest I saw and that was at 3000rpm ish! so now im wondern, why, is my turbo worn out? i just have a superchips programer and its not turned up more than 50hp or so but i though i should se atleast 25psi bad sensor? or low boost due to bad turbo or lack of fuel, note: i do get a lil black smoke in the lower rpms up to 2100 or so and have tymar filter
no cat, no muff

 

[andrew974x4]

that doesn't sound to far off but i would think that it would be a "little" higher than that. your turbo is most likely not the cause. do you have the stock downpipe in yet? that would do it. or maybe a leak in the system after the inatke side of the turbo. youre 95 could be leaking at the intake plenums cause in 95 they used 2 less bolts to hold down the intake plenums and this is genrally where they leak from... but if that were the case you probly wouldn't even see 19 psi but its worth a look.

but definetly do a downpipe. when i first got my 97 it couldn't spin the tires even turning and getting on it... i did just the downpipe and she spun them alright so you will feel it /ubbthreads/images/graemlins/grin.gif i will probly be selling my downpipe for cheap with in 30-40 days if you want to keep in touch or check the for sale section.

 

[Krogg]

i have a stock DP but every thing else is tight, just did a good bit of work in there, had it all apart, dropped a nut dow the plentum while doing a fuel bowl repair, PM me Ill by that DP off ya

 

[doby86]

that boost pressure sounds about right for an older 7.3 powerstroke, my 96 only gets to about 17 pounds at 2500 rpm and i've read some articles that say the same

 

[ryanPSD]

Yeah that's about right. If you're only seeing a tiny bit of smoke at best the chip isn't putting that much in. More fuel is more boost, and more boost is easier with a downpipe.

Bone stock should usually be like 14-15psi.

 

[97f250RED]

well my truck all stock with just the downpipe(stock) disconnected at the kitty was making 24lbs with no chip programer or injectors....

now i hit 26

with 3x3.5 inch DP
chip and modified IDM from swamps

i cant wait to get some bigger injectors /ubbthreads/images/graemlins/smile.gif if only i wasnt a poor college student huh? anyone wanna donate money to me to get injectors? lol

 

[lukecline]

i could only get 20 psi with stock injectors, intake, exhaust, and edge evolution. I only see 30ish right now with all my mods.

luke

 

[ryanPSD]

30 on Stage IIs?? I can hit 34.

 

[lukecline]

yep thats all i get /ubbthreads/images/graemlins/shrug.gif, cant explain why or how. well i guess a week or so ago it was brought to my attention that i have a pre turbo up-pipe leaking a bit.

 

[Guest]

Post deleted by JLester

 

[ryanPSD]

Wow...

I was expecting you guys to be able to just tap the pedal and smash whatever boost the Stage I's make like it was nothin.....

I don't think my turbo is too happy with the 30+ I like to do all too often, though. Gotta check the play in it this weekend.

 

[Guest]

Post deleted by JLester

 

[andrew974x4]

weird! cause with my 2.5's i can hit 45 psi as a guess~ can't tell cause the needle just points straight down and shakes real bad /ubbthreads/images/graemlins/grin.gif time for the 60 psi guage. also the boost comes on real fast /ubbthreads/images/graemlins/smile.gif

 

[barrybaker]

I seem to be having boost issues also. With all my mods while pulling a loaded (with 3 big horses) heavy 30ft. gooseneck 3 horse trailer with living quarters and all suppleis needed for 5 people for a weekend up to about 9500ft. in the mountains of Colorado for the July 4th weekend. The best I was able to do was no more than 15lbs of boost while trying to keep the egt's to no more that 1200 up 1400 for short periods. While towing flat and level in it hardly register 2 or 3 pounds at 75mph. I know I have low compression issues on the engine and will be pulling it at the end of the month and pulling heads. At the same time I will check the donut gasket cause I think I am leaking there.

I pretty much have my wife convinced that buying a rebuilt complete drop in for $7500 with new turbo and such is the way to go (don't really have the time for a rebuild) and then I will just move my mods to the new engine.

Barry