Back pressure

[97Stroker]

I have a stock truck with a 3in downpipe 4in exhaust to a 5in 90 and a 5in stack. I've had it for a while and now it seems to be alittle down on power and it almost sounds like its missing under decent to hard acceleration. I always thought the turbo was enough back pressure but am I wrong?

 

[Tom S]

It is not missing because to back pressure. I might more suspect fuel pressure.

 

[97Stroker]

Well yeah, its just not as smooth sounding accelerating as other 7.3l's. It kinda sound like a 6.0 just not that crisp. Could my lift pump be getting too weak to keep up with a higher demand of fuel? Or would that want to try to stall the truck?

 

[Tom S]

I think I would check the fuel pressure for a preliminary check if it was mine and then look further. It is not hard to fab up a gauge to check it.

 

[97Stroker]

Alright

 

[Magnum PD]

Just remember that the pressure is gonna flutter real bad. Not a steady reading.

 

[Tom S]

A liquid filled gauge helps for reading it.

 

[Estrogen Hostage]

I wonder if what you are describing isn't an exhaust leak pre-turbo?

Definitely start where the above posters suggested as it's very easy to eliminate, but I might describe a pre-turbo exhaust leak like you did.