I just bought an 04 and when looking on the side of the motor, it says 305hp. My sister in laws husband recently bought an 04 and his says 325 HP on the motor. I am guessing his is the 04.5, but both of our motors are listed as HO's. What changed half way through the year and why would they both be listed as HO? Or should the 04.5 read EMHO (Even More High Output?)

Thanks,

 

I think that its just a programming thing.

 

I dont know what the mechanical differences are but the outputs are 305/555 and 325/600. the '05's have the 325/610 motor.

 

What about the 250/460?

 

the 250 sounds like a standard output model or the cali edition.

differences between the 305 and 325, mostly programming, however, the injectors are different, the block has some internal gussetting to handle the higher torque output, the pistons and rods are made from a slightly different metal compund and I believe the valve seats are a bit different to handle the heat from the exhaust better.

the difference between the 600's and the 610's only is a programming difference to help in keeping the white smoke on startup to a minimum, and also to get a one up on chevy when the LLY's had 605 torque

 

Steve,

FYI, Not all 05's had 325/610. I had looked at several in Feb of 05 and they were listed as 325/600 on the window sticker [sm=nerd.gif]

 

well then....I guess that means I just have to buy some mods to make up the difference.

thanks for the info.