ISB 235 engine and boost

[bill8333]

I think I have a problem but I'm not sure. First lets start with the truck. The black mule is a California truck with a production date of 12-03. She has the ISB 235 engine or 235/465 power plant. She's a quad cab s/b auto trans with 410 for a driveline.

I installed boost gage, pyro, and trans temp all at the same time. The truck has never seen anything over 22lbs of boost since day one. Even after I install the quad box 30-60-100 she still only gets to 22lbs can anyone with an 04 tell me your boost numbers?

I don't want to look for a problem if I don't have one. The truck runs fine and has never been to the dealer for warranty work, I guess I just got lucky. Just in case I just ordered a new isspro boost gage that reads only 30lbs of boost instead on the 60 that’s on her now.



Thanks up front

Bill

 

[Bertram65]

Sounds normal, though the boost comes up much sooner and builds much faster. I have the same setup. The '03 SO with CA emmisions is 235hp and 465ft/lbs torque also not 440ft/lbs stock.

 

[Tomeygun]

I think I have a problem but I'm not sure. First lets start with the truck. The black mule is a California truck with a production date of 12-03. She has the ISB 235 engine or 235/440 power plant. She's a quad cab s/b auto trans with 410 for a driveline.

I installed boost gage, pyro, and trans temp all at the same time. The truck has never seen anything over 22lbs of boost since day one. Even after I install the quad box 30-60-100 she still only gets to 22lbs can anyone with an 04 tell me your boost numbers?

I don't want to look for a problem if I don't have one. The truck runs fine and has never been to the dealer for warranty work, I guess I just got lucky. Just in case I just ordered a new isspro boost gage that reads only 30lbs of boost instead on the 60 that’s on her now.



Thanks up front

Bill

I believe that is your wastegate opening - without modifying it will open at 22psi no matter the amount of fuel

 

[bill8333]

If I modify it, how do I do it, and what are the pros & cons of it.



Bill

 

[bill8333]

Thanks I changed it. Have you done anything as far as mods go to your truck??



Bill

 

[Tomeygun]

Thanks I changed it. Have you done anything as far as mods go to your truck??



Bill

Too many to list - See signature above...

 

[Bertram65]

Thanks I changed it. Have you done anything as far as mods go to your truck??



Bill

I have a Magnaflow muffler in place of the stock muffler, still have the cat, a AFE magnum force air box replacement with a pro guard 7 filter, torque tube, guages, and the adjustable quad box. I have about 47k miles on it, so far it has been great. The only thing that make a noticable difference other than noise was the quad box.