Jbark2010

Hey guys my names jeremy I'm new to this site though I've been reading here and there for years this is my first post.

I have a 2004 F150 4x4 5.4 that we just rebuilt and bored .30 over less than 3k miles ago. The truck had a rough supercharger non intercooled kit on it when i bought it but the motor had blown the rings in 2 cylinders so i rebuilt it.

The supercharger is making 5 PSI at its max right now from what i can see on the boost gauge.

I took the truck to a local Dyno tune shop as soon as the motor was reinstalled because i was afraid of the rough tune killing rings again and i installed cam phaser lockouts and needed them to be tuned around.

Ive read that other users saying they are making 320-340 RWHP with similar set up

My set up made only 275 hp and 322 Ft lb torque at the wheels on its best run

Do you guys have any idea why it would be such a low number?
Truck seems to run fine, I run premium in it and don't have any CEL on or any misfiring or running badly.

here is my dyno sheet

4.6owner

What is your ring gap set at? Forced induction will always require a slightly wide gap to prevent ring bind once boost gets turned up as to not crack a piston. However you never stated if you had your supercharger gone over.

jshillin

iTrader: (1)

What kind of Dyno? Dynojet or Mustang? The numbers you have heard, are they at the crank or the wheels? If at the wheels, what kind of dyno were they on? You generally see a pretty good difference between the 2 dyno's.

Jbark2010

The dunk I don't know the brand I could call them and the engine was rebuilt to OEM ford specs no additional ring gap

4.6owner

I was thinking you were getting blowby if the gap was large because maybe the engine was purpose built for more boost. 5 PSI is nothing and if built to ford specs then you should be good. I have to lean toward the dyno being stingy or maybe a fuel issue if you are low on power. What was the air/fuel ratio at WOT? Are you lean or having any driveability issues at all? What were the IAT's? If you are non intercooled perhaps you were heat soaked.

Jbark2010

The truck is slow i would never pay someone to put this kit on but it does run fine

it had 12.1 AF on its best run the one that made 275 there are pics of the AF in the dyne above for all 3 runs

Jbark2010

and i don't have any intake temp numbers whats the best way to get them?

105th BLOWN HD

What supercharger? What mods? All stock components?

Jbark2010

Its the roush non intercooled kit. it had a roush super charger roush intake and roush ECU. i had the ECU dyne tuned now tho since the ROUSH eco detonated and blew 2 rings Not 100 percent sure about the injectors. The motor was rebuilt to OEM specs but .30 over because the rings scored the cylinder when the went before i rebuilt it.

Jbark2010

mods are CAI , dyno tune, cam phaser lockouts, and really thats about it.