boost

[bdixon2138]

I have a '97 7.3 PSD. The truck has a 3" downpipe to 4" exhaust, TS chip with Wildman tunes, Tymar cold air intake, a Dominator D66 turbo from Beans Diesel, and Autometer Boost, Pyrometer, and Tranny guage. My question is: How much boost should I be getting? I am currently only getting 8-10 lbs under full throttle. I replaced the turbo about two weeks ago and was getting the same amount with the stock turbo. I inspected the plenum boots and all was good. I have always been a Cummins guy so I dont know a great deal about the PSD. Also, my EGT'***** 1200 on any kind of incline. This is with the truck empty with the chip on economy or stock. Tranny is automatic with 3:55 gears. I live at 6000 feet so could this affect it? Any advice will help.

 

[94f450sd]

what are you running for injectors?the truck in my signature runs 36PSi before the intercooler/28PSI after the intercooler

 

[bdixon2138]

Stock injectors.

 

[94f450sd]

ok well with stock injectors you kinda went backwards with your mods that you have done.in order for everything to work right you need bigger injectors.with stock injectors you can do all the mods you want but youre only gonna see another 75HP out of it.i would expect to see your boost and pyro readings to be where they are.your not dumping enough fuel to spool the turbo so you see low boost levels and high egts like you are.dont keep the egts at 1200 or higher for too long.

 

[bdixon2138]

I was getting the same boost when everything was completely stock. Is 8-10 psi normal for a stock '97? I have heard everything from 10-25psi. Also, my EGT were the exact same when the truck was completely stock. I could easily hit 1200 empty. I am getting ready to add hybrid injectors and a BTS tranny, however I want to figure this problem out...if there is a problem.

 

[94f450sd]

there is no problem now except your not even spooling that turbo yet.put the injectors in and then see what it does.around 15psi is normal for a stocker IIRC.but your not getting enough fuel for the turbo to work yet.

 

[zpd307]

replace your plenum boots, you will see your boost numbers increase.... they are a known weak link after so many years of use. i replaced all of my boots, granted i have a 99 with an intercooler, but i gained 4 psi with new boots.

 

[97idi]

check the up pipes going to the turbo they can break and the seals will fail causing low boost, with a stock truck you should beable to hit 15psi hope this helps

 

[94f450sd]

hes not dealing with a stock truck truck.hes dealing with a bigger turbo and stock injectors.upgrade the injectors and the boost will go up to where it should be

 

[rebel_horseman]

Just a thought...have you cheked the line that is giving your boost readings to make sure that it is not clogged at any point (from where it makes it connection to the gauge) and did you make sure the line is not kinked in some way.

Stock you should be well north of 10psi even with your mods.

 

[FordGuy100]

If he was seeing that same boost with the stock charger, something is up. Not just that his injectors are stock.

Like said, start looking. Is there any soot on the up-pipes? Definatly have a boost leak, or an uppipe issue.

 

[OLDBULL8]

Was just in Casper WO about ~3 weeks ago and dropped off a 33 Ford Coupe at a place where they clean petro tanks and haul water. Can't remember the name of the place.
That altitude may have something to do with the lack of boost, my 99.5 "stock" would not go over 15 PSI boost pulling a 35' TT, the EGT reached 1250 tho pretty quick. I am able to get 18-20 at lower altitudes and lower EGT's.
That's the Ford Coupe.

 

[bdixon2138]

I keep wondering if the altitude has something to do with it. I have never driven the truck at sea level, so I am not sure what it would be like. I am looking at the up pipes. I did replace the plenum boots but no boost increase. I do think that 10psi is too low on the boost side, however. The truck only has 46k on it.

 

[94f450sd]

upgrade the injectors and see what it does.you are not dumping enough fuel to spool that turbo.your mods are calling for fuel that you cannot supply with stock injectors.big turbo requires more fuel to spool it.

your egts are gonna be high.again your not dumping enough fuel to spool the turbo to blow enough air to cool it down.basically youre runnin on the lean side.id also have to think your fuel mileage is down a bit as well?

 

[tech51]

If you staying with stock injectors then run a 1.0 housing.