4.8 is 285hp / 295 tq

 

Do you know when GM upped it because it was in 2000 that the 4.8 and 5.3 each went up 15hp making them 270 and 285? Thanks for the info.

 

'03 I believe.

 

my buddy has an 01' with the 4.8M5 and we've been playing with it as we go. we've installed edelbrock shorty headers, flowmaster cat back, k&n fipk, and eaton limited slip (his had the 3.73 option already). it certainly pulls well and after i modified the lower spring slapper the majority of the wheel hopping has went away. the trans is absolutely terrible and we are planning a 6 speed conversion like on the berger truck (i spent about 10 minutes crawling under it this past weeekend). the next mod for his will be hptuners and more cubes in the spring.

 

What do you do to the spring slapper. This is the first time of heard this.

 

buy some cal-tracs to get rid of wheel hop. intake, gears and full exhaust will wake your truck up alot. you could look into a cam too. Something like a 224/224 114lsa. I know where you will be able to get one cheap... oh ya and get a radix not a turbo too.

 

i'll try to get some pictures of this tomorrow. it doesn't wheel hop when laying into it since i've done this to it. after the headers were installed he was going to do a burnout and it wheel hopped so bad the driver side header hit the steering shaft. after that i did the mod and it now only will try to hop if your just barely into to it and the tires break loose (like rain, dirt, etc.). we'll probably put cal trac's on it once it gets to the point where it has a traction problem.

 

The factory MG5 five speed does suck, the more I drive it, the more I realize this. I think 3rd gear is really long winded. That's why I asked would 3.73's improve it alot. I realize 1st gear is very low, but the difference it would make to the 3rd gear should help it out alot. The truck will run 90+ in 3rd gear w/ the 3.42.

 

if you're considering changing, 4.10 might be a good choice also. 3.73 does work better than the 3.42, but that damn 2-3 split is a bitch either way.

 

Yes , my truck is a auto .. I forgot you have a Manual . Put a Posi unit in there ..