How much is too much

[BBB]

I plan on ordering a new injection pump injectors, this summer. I am open to a intercooler and upgrade the turbo. My question is what cc pump is too much? I have a NA 7.3. That I have added a factory turbo from a 94 onto it.
Engine has had a quality rebuild 40,000 miles ago and has a E 4OD. I replaced the factory turbo down pipe with the better pipe. I was. Looking at classic diesel. I live in central kansas pull some heavy loads is. 90 cc ok or should i go bigger. I dont plan on headstuds just yet. But can always do it if needed. Thanks for any advice or previous examples

 

[chillman88]

I dont plan on headstuds just yet.

Then I personally wouldn't buy a bigger pump. You may get lucky, but a bigger pump gives you more boost, which is what blows head gaskets.

Stud it up and then upgrade your fuel!

How do you USE your truck? Do you tow ever or all the time? I'm debating if I want to go bigger than a 90 or not because I do haul, and power is nice, but I don't want to be staring at an EGT gauge all day pulling hills around here.

 

[IDIBRONCO]

If you want a little bit more, run the IP off of the Factory Turbo engine. Those can put out some pretty impressive numbers when they are maxed out. I wouldn't buy a bigger IP until your engine is ready like Chillman88 said. Then I'd buy both IP and a set of injectors. I don't see any need to only go with half an upgrade unless your injectors are pretty new without a lot of miles on them.

 

[BBB]

Yes i missed a comma. Injection pump, injectors. . The factory turbo pump is worn out I will replace both at same time. So without studs i should. Stsy stock calibration.

 

[IDIBRONCO]

That would be the best bet for now.

 

[Black dawg]

Have people really been having reliability issues on 7.3s without head studs??

I have zero reservations of running a 7.3 with stock bolts at anything around 15psi.....sustained.....like all day....maybe ok with more, but that is the level of boost (with fuel to match) that I have experience with.

 

[Black dawg]

I do agree though, the stock pump maxed out and boost adjusted to match, makes good power.

 

[Black dawg]

I should add that it takes cool wet weather to be able to run one that hard (15psi and 11-1200egt) without coolant temps being an issue.

 

[BBB]

Thanks. I ordered a pump, injectors and a turbo from R&D. Went with the 80 cc
If I am not happy I will stud it. but I am thinking I will be happy.

 

[IDIBRONCO]

Have people really been having reliability issues on 7.3s without head studs??

I have zero reservations of running a 7.3 with stock bolts at anything around 15psi.....sustained.....like all day....maybe ok with more, but that is the level of boost (with fuel to match) that I have experience with.

Generally, the rule is 15 PSI with a 7.3 with head bolts is about the safe limit. That's not to be taken for gospel, but it's a good, safe guideline. Maybe one will have issues at 13 PSI while the next one can run 20 PSI all day without any issues. At your 15 PSI, you should be fine.

 

[Black dawg]

Generally, the rule is 15 PSI with a 7.3 with head bolts is about the safe limit. That's not to be taken for gospel, but it's a good, safe guideline. Maybe one will have issues at 13 PSI while the next one can run 20 PSI all day without any issues. At your 15 PSI, you should be fine.

And It has been fine for a couple hundred thousand.....I have not seen a 7.3 have a fire ring headgasket leak/failure, and this is over many personal trucks and friends trucks, and working on these now for 25 years. None have been set up to make more than 20 psi, but I have personally driven a few hundred miles with a boost gauge at 19-20 psi and pyro 1200ish loaded heavy with a headwind.

I just dont think it is an issue with a 7.3??

6.9, I recommend studs even without turbo.

 

[chillman88]

Well I won't speak for anyone else, but this is the way I feel about it.

$500 for a set of studs, another what, $100 for gaskets? Plus a few hours of work.

How much would it cost to have my truck and 5th wheel hauled 1000+ miles home? Not to mention anything else such as non-refundable deposits or deadlines missed.

I'm just not one to gamble too much. I'd rather do it once and not worry about if it might fail, especially when turboing something that I don't know what shape the head gaskets are in anyway. Factor in new head bolts when you're already doing head gaskets and the price difference is even lower. It's good peace of mind in my book.

An ounce of prevention so to speak.

 

[ttman4]

Well I won't speak for anyone else, but this is the way I feel about it.

Well soon as I get my shop built/finished I'm gonna stud & stuff, turn mine up, & start making private trips to outer space & back. Compete with that guy down there in NM that made that trip to space & back other day!!!!
It'll be in my '90 CC dually.... anybody want to go?

 

[IDIBRONCO]

I'd rather do it once and not worry about if it might fail, especially when turboing something that I don't know what shape the head gaskets are in anyway.

This is why I never recommend replacing one bolt at a time with a stud. That and the fact that you can't properly clean out the bolt holes with the heads in place.

 

[u2slow]

I plan on ordering a new injection pump injectors, this summer. I am open to a intercooler and upgrade the turbo. My question is what cc pump is too much? I have a NA 7.3. That I have added a factory turbo from a 94 onto it.
Engine has had a quality rebuild 40,000 miles ago and has a E 4OD. I replaced the factory turbo down pipe with the better pipe. I was. Looking at classic diesel. I live in central kansas pull some heavy loads is. 90 cc ok or should i go bigger. I dont plan on headstuds just yet. But can always do it if needed. Thanks for any advice or previous examples

This publication weighed heavy for me in deciding how much I was willing to play with turbocharging the NA engines:

http://www.forddoctorsdts.com/forddoctorsdts/download-2.php?f=939473IDITurbochargedDieselEngine.pdf

Specifically the "Internal Parts Changes". Keep in mind these changes were for a stock turbocharged application - not a performance one.