03 to 05 horsepower what's the differance?

[jhawk1187]

My 03 is rated at 285 hp the 05 is rated at 295 and the 05 Z71 is 310 hp
I know the increase between the two 05 engines is achieved by a 1\2 point compression increase.
My Question is what did they change for ten hp between the 03 285hp and the 05 295hp?

[smpldezine]

efans worth the 10 maybe??

[Colby 04]

efans worth the 10 maybe??

negative, the engines are dynoed with no accessories(or so I've been told). You'll notice the 04 5.3 with a mechanical fan and the 05 5.3 with electric fans didn't net a horsepower gain. the 05 is rated 295 and the 04 is rated 295. The increase in HP took place on the 2004 year model....both the 4.8 and 5.3 went up 10HP as far as the difference....I dunno

[Nick]

negative, the engines are dynoed with no accessories(or so I've been told). You'll notice the 04 5.3 with a mechanical fan and the 05 5.3 with electric fans didn't net a horsepower gain. the 05 is rated 295 and the 04 is rated 295. The increase in HP took place on the 2004 year model....both the 4.8 and 5.3 went up 10HP as far as the difference....I dunno

[smpldezine]

I thought I had it lol... thanks Colby for correcting me.

[jhawk1187]

anybody?

[Atomic]

Some of the 05s had the aluminum block while 04 had the iron block. And I think maybe different heads (Aluminum vs iron)

[Colby 04]

Some of the 05s had the aluminum block while 04 had the iron block. And I think maybe different heads (Aluminum vs iron)

The 05's with the aluminum block are the HO motors(5.3 HO), and all the heads on the gen III vortecs from around 2001 and up are aluminum.

[Gran Patron]

I would guess it had something to do with the stock tuning differences.

[1LOW4X4]

who knows, it doesnt even really matter on the street, mine will run just as fast as an 06. i can see your curiousity though.

[Nick]

The 05's with the aluminum block are the HO motors(5.3 HO), and all the heads on the gen III vortecs from around 2001 and up are aluminum.

I'm pretty sure my '99 had aluminum heads too.

[Colby 04]

I'm pretty sure my '99 had aluminum heads too.

"around 2001" - that includes '99 engines....

[1LOW4X4]

"around 2001" - that includes '99 engines....

lol silly boy...

[Atomic]

The 05's with the aluminum block are the HO motors(5.3 HO), and all the heads on the gen III vortecs from around 2001 and up are aluminum.

oh...hmm....

[oldred95]

My dads 05 half ton crew 5.3 is rated at 295. My feelings are for every 10 HP they add, they take away another 30 HP via torque management. His 02 Z71 loaded will run circles around the 05 empty.

[Nick]

"around 2001" - that includes '99 engines....

:LOL:

[black04z71]

This is the question I have the Trailblazer SS are rated at 390 with the LS2 and I read that it was 10 les HP because they couldn't use the Efans. I havn't look under the Trailblazer SS and my 04 is rated at 295 without efans. So I don't think its them just a little weird why it would be on one motor and not anoter. I am sure its just a little differnce in tuning and I think old red is right with the TM. I read somwhere else on here that there is more TM in the 05 models then the 04 the 04 have more then the 03.

[sleeper357]

The 05's with the aluminum block are the HO motors(5.3 HO), and all the heads on the gen III vortecs from around 2001 and up are aluminum.

It is the HO 5.3 310Hp 335tq in the z71, alum block and heads. I think it was also used in the 2yr run on the SSR before they added the 6.0

[Colby 04]

This is the question I have the Trailblazer SS are rated at 390 with the LS2 and I read that it was 10 les HP because they couldn't use the Efans. I havn't look under the Trailblazer SS and my 04 is rated at 295 without efans. So I don't think its them just a little weird why it would be on one motor and not anoter. I am sure its just a little differnce in tuning and I think old red is right with the TM. I read somwhere else on here that there is more TM in the 05 models then the 04 the 04 have more then the 03.

Where did you "read" that?

You can't always believe everything you read

[Nick]

This is the question I have the Trailblazer SS are rated at 390 with the LS2 and I read that it was 10 les HP because they couldn't use the Efans. I havn't look under the Trailblazer SS and my 04 is rated at 295 without efans. So I don't think its them just a little weird why it would be on one motor and not anoter. I am sure its just a little differnce in tuning and I think old red is right with the TM. I read somwhere else on here that there is more TM in the 05 models then the 04 the 04 have more then the 03.

The TB SS has a more restrictive exhaust than a Vette.