maximum boost????

[socodieselpower]

whats the most boost i can put to my 7.3 before i have probs, heads-- or boost codes----- any takers

 

[guzzle]

Somewhere around 23-25 psi, the MAP sensor will have the PCM set a P1249 overboost code. The PCM will then sense the need for a defuel condition which calls for actuating the wastegate. None of this will cause damage to the heads but most believe that boosts of 30+ psi will cause premature wear on the compressor wheel bearing in the stock turbo. Any 7.3 built after 10/00 is limited to about 350 RWH on modification due to the PMRs that Ford began using at that time. Modifications above that will usually cause windowing of the block.

 

[Hoss 350]

whats the most boost i can put to my 7.3 before i have probs, heads-- or boost codes----- any takers

The stock turbo will not live for very long if you are making boost above 27 psi regularly. If you put an aftermarket turbo on, you will still get a defuel code at 25 psi. If you put a MAP blowoff to control the pressure the MAP reads, then you can go to about 40 psi before the stock headgaskets begin to become a question. That said, making 40 psi, you are going to be getting really close to the maximum HP that PMRs can take, as was stated before.

IF you blow a headgasket witha n overboost, then I would HIGHLY recommend that you tear the engine down right then and there, without driving it even easy at all until you get new rods in it. The reason I say this is because most of the rod losses that I have read about came within days of a headgasket repair due to overboost. The threshhold the headgaskets have for popping is about the same threshhold the rods have for doing likewise.

IIRC, Dockboy, Bbunting, and a couple others all blew headgaskets, then a couple days later, under low load, low stress conditions, put windows in their blocks. (I may be wrong on the details of each occurence, but I'm pretty sure I'm accurate on the coorelation.)

Anyway, hope that helps.

 

[CSIPSD]

As was said- stock turbo 25-27, HG about 38-40. The limit for PMR's is going up with cylinder pressure testing, I'm testing a new chip that should put me to the limit with the stock turbo and injector's...

 

[Dockboy]

IIRC, Dockboy, Bbunting, and a couple others all blew headgaskets, then a couple days later, under low load, low stress conditions, put windows in their blocks. (I may be wrong on the details of each occurence, but I'm pretty sure I'm accurate on the coorelation.)

Anyway, hope that helps.

I have never blown a headgasket

 

[Hoss 350]

I have never blown a headgasket

I guess I remember reading that you had just got done fixing a headgasket when your truck went bang (IIRC, you were towing a bobcat skidsteer or something similar?)

Sorry, I must have been wrong...

 

[GREGROB]

There's no real reason to run the stock turbo much past 25-27psi anyway, it's way out of it's efficiency range above this boost.