Jump to content

03 engine line-up revision...


Recommended Posts

Not a 6.0 SS question but, as far as I know in 03 the 4.8's and 5.3's were upped by about 30 horse. I think the 4.8 went from 255 to 285. Wondered if this was due to a mild head redesign, bump in compression, or a simple cam change? Just wondered as I may be picking up a 99 4.8.

 

 

Thanks.

Link to comment
Share on other sites

The HP has been on the rise from 99 on the 2003 on all the motors. I had a 99 4.8 myself. As far as I know tuning is the only difference on the 99 and 03 models. I am sure Zippy could help with this question.

On my 99 I did a volant air kit and a Diablo Tuner and cut .5 sec in the 1/4 mile.

 

Good luck on your shopping.

CD

Link to comment
Share on other sites

Not a 6.0 SS question but, as far as I know in 03 the 4.8's and 5.3's were upped by about 30 horse. I think the 4.8 went from 255 to 285. Wondered if this was due to a mild head redesign, bump in compression, or a simple cam change? Just wondered as I may be picking up a 99 4.8.

 

 

Thanks.

To the best of my knowledge, all the HP boosts have been by tuning only.

 

Butch 02 Sierra Denali

Link to comment
Share on other sites

To me, that seems like a lot to pick up by tuning - unless GM deliberatly used a conservative tune on the earlier ones... :confused:... also I noticed that the early rating of 255 for the 4.8 was at 5200 - the 285 rating was at 5600. That makes me think cam or intake manifold changes... LOL, maybe I am too used to imports (30 seems huge for factory tuning) - I suppose on a 300 horse engine a gain of 30 is only 10% so maybe it was more agressive tuning...

Link to comment
Share on other sites

if i recall it went like this.

 

4.8.... 99=255hp, 00=270hp, 01=270hp, 02=270hp, 03=285hp

5.3.... 99=270hp, 00=285hp, 01=285hp, 02=285hp, 03=295hp

6.0 (8600gvw version) 300hp from 99 up.

6.0 320 first year C3/denali 320 later upped to 325

6.0 SS and escalade 345hp.

Link to comment
Share on other sites

if i recall it went like this.

 

4.8.... 99=255hp, 00=270hp, 01=270hp, 02=270hp, 03=285hp

5.3.... 99=270hp, 00=285hp, 01=285hp, 02=285hp, 03=295hp

6.0 (8600gvw version) 300hp from 99 up.

6.0 320 first year C3/denali 320 later upped to 325

6.0 SS and escalade 345hp.

Well, I hate to say it but zippy is wrong. The '01 C3 came with 325hp, so did the Sierra Denali.

496091_11_full.jpg

Link to comment
Share on other sites

good catch naked av, you are correct. entering this stuff in while watching tv, typing on chat, and doing other stuff can catch me off guard. as for the c3, just going by the paperwork i have which very well could be incorrect, it shows the first year for it was 320 and upped to 325 the next year. i believe you are correct C3, thanx for catching that.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...