Couple dumb questions

[spencergt66]

Hi I'm new to the site Ive been looking for a site like this for a while I just bought a 93 f350 4x4 7.3 turbo IDI with a 5spd good truck little rough around the edges but for 2grand i couldn't say no Ive been reading some on the engine here and there and found out that the stock turbo only puts out 3psi? And that the stock exhaust is a major restriction iv have had Chevy 6.5 diesels and a 7.3 psd and a dodge i just want this thing to run like it was suppose to you know good boost (10psi) and a good exhaust tone and i don't feel like spending another 2 grand on parts whats the best way to get the boost where it should be and where can i get a good straight pipe exhaust system i cant really find anything on any other sites thanks Spencer

 

[jperecko]

That does not sound right. The stock setup should put out at least around 10 psi. If not, start checking for boost/exhaust leaks.

 

[RLDSL]

If not getting enough boost, chances are the factory muffler is clogged with many years of soot to the point where the turbo can't spool up. Heck when I installed my turbo I couldn't get more than about 3 lbs boost until I ditched the factory exhaust and put a 4" system on with a straight through big truck muffler on. Funny part was the muffler was so clogged with soot that the thing was so stinking heavy I couldn't even lift the thing Talk about taking a cork out of it , between that and turning up the fuel a flat she was good to go.

Now you haven't mentioned how many miles are on the thing. or if it still has the original injectors and injection pump ( easy to tell, if they still have gray paint on them ) but they may be getting tired. Also it doesn't hurt to advance the timing a bit to 9.7 deg by the pulse method to compensate for the new fuel. It will recover the power that was lost in the fuel transition.

 

[k_williams1982]

I have my pump up two flats, 4" straight piped exhaust, and I can hit 10 psi boost easily. I'm going to turn the pump up another flat or two because I'm starving it for fuel after 3,200 rpms right now. Check for exhaust leaks or a restriction somewhere (getting rid of the muffler is a good place to start).

 

[spencergt66]

O i have checked for leaks and i do have one exhaust leak on the drive side that needs to be fixed but from what i was reading on another sight the 7.3 turbo came stock only putting out 3psi of boost this truck is almost all stock it has a new pump on it and seams to run pretty good this first thing i plan on doing is getting a stright pipe like 4" put on i just can seam to find one this is a factory turboed engine it doesnt have a kit on it is there aftermarket wastegate actuator or can i just adjust the one on the truck and also where can i find some info on increasing the timing on the engine thanks you guys are a real help

 

[spencergt66]

o forgot to say but the truck has 224k miles and seams to still runn like a rapped ape but it will role the cole when you lay into it

 

[RLDSL]

Use the search feature, we've covered the timing thing extensively

 

[subway]

you should be able to pull 6-8 psi out of even a stock system without a problem. i have a stock system and i can hit 8 and i have not tinkered with it at all. do you have a gage to confirm your boost numbers.

the stock down pipe is a big restriction. if you look at it you can see where it is flattened out for clearance reasons. i am not sure but i have heard the early powerstroke down pipe will fit our trucks. i want to look into that since i am currently running the the stock one i put in "just for now".

 

[spencergt66]

No i don't have a boost gauge yet i think I didn't explain my question clearly though. I was only wondering if what i heard was true, that is that in stock form or setting i have read in several places that the turbo will only put out 3 psi of boost but from reading everyone else's comments it sounds as if that isn't true sorry for the confusion the first thing i plan on doing is putting a 4" exhaust and a bigger down pipe just haven't found one yet and some gauges

 

[Dsl_Dog_Treat]

Get that exhaust leak fixed. Even the slightest leak WILL affect boost, plus that will be putting in more fuel than air which may be a culprit to the coal rolling.
Not enough air going in.


Welcome to OB!

 

[spencergt66]

Ok i found the exhaust leak its coming from driver side pipe at the manifold shouldn't be too bad to fix i think. Speaking of exhaust where can i find a exhaust system for this truck or at least a down pipe i havent had much luck on the internet so far any one know of a place?

 

[Agnem]

Hypermax sells a complete performance exhaust system. Banks used to. Most guys here now, either fab up their own, or adapt one from a newer truck. OBS Powerstrokes are virtually the same until you get within a couple feet of the turbo. Anything more than 3.5" diameter is a waste performance wise, but bigger can look and sound better.

 

[91f2504x4]

I was just reading over the factory shop manual for the 7.3L Turbocharged IDI and it says that when testing the engine for boost it should put out a minimum of 5 psi.

It also says that when testing the wastegate actuator that the rod shouldn't start moving til between 12-15 psi and it should be at full travel by 20-22 psi, so according to that the wastegate shouldn't even start to open until 12 psi at the minimum, that doesn't seem right, with what I have heard about the stock turbo trucks.

 

[Agnem]

Sounds more like your reading the DI manual, and not the IDI manual.

Exactly how do they suggest to 'test it for boost' ?

 

[91f2504x4]

Sounds more like your reading the DI manual, and not the IDI manual.

Exactly how do they suggest to 'test it for boost' ?

Go to Page 33 of this manual

and it is for the 7.3L IDI Turbo Engine