BlackGMC

iTrader: (31)

Well I have been reading up on all of these for the last few weeks and I think I have decided on what combination I want to go with. I don't want anything extreme, just a little bit more go. Keep in mind this is my only vehicle that is drivable at the moment and I don't want it breaking on me. The truck is a 2004 RC 4.8 auto w/3.42, exhaust and CAI only.

This is in the order I will be installing/buying

Software:
HP Tuners
Wideband 02

Gears:
3.90 (i have heavy *** 20's w/ 31' tire)

Converter:
Yank 2600

Cam:
Comp Cam 212/218 114lsa low lift (.522 .529)
+supporting valve train stuff (springs, etc.)

As you can see all of this is not the biggest size but enough to notice a difference and keep the truck from breaking.

So do yall think this combination will wake up the 4.8? My main goal is to show up the SPEEDO wearing, Honda Civic next door neighbor.

BlackGMC

iTrader: (31)

ttt...

moes04silverado

iTrader: (2)

that all will wake it up for sure....

i went with the TR224 cam....WOW is my only comment...

i would get a dyno tune if you have the local access, you performance will be much better...

Colby 04

I would go 4.11 on the gear

I have a 4.8 with heavy *** 20's and 31" tires, my gas mileage went up when I swapped in the Yukon 4.11's. It drives sooooooo much better now, it's not struggling to get around, especially on the highway.

BTW, I had 3.42's

Colby 04

I'm shocked, everyone I've talked with about cams(because I'm no expert), has always said the TR224 was too big for a 4.8 in an extended cab. How well does your's run?

I put the 224 in my 6.0....which will find it's way in my truck this weekend

vanillagorilla

iTrader: (1)

I don't think the TR224 is to big for an EC. You just need the proper tuning and a little more stall. I second the 4.10/4.11 gears too. Anything less with that tall of a tire would be a waste.

If you want a nice 4.8 RC setup, check out Thunder's threads and website. If you do go with a comp cam, at least get the high lift version. The low lift profiles are about as lame as my cam's.

moes04silverado

iTrader: (2)

to be honest with you its really powerfull at the top end right now...i do need to swap some different gears, get a 3000 stall in there and re adjust my tune a little...but other than that, which is a lot it runs real good... the first time i had it tuned was with only the longtubes on there, nothing else...not even o2's...so i feel that i am not getting the potentional power that i could be getting....it did make 275 RWHP when it was first tuned... but like i said above, i still need to finish....just need some $$$$$$$

blackGMC: I think that is a good cam but i would try to find one with more valve lift at the same or close to the same duration...

BlackGMC

iTrader: (31)

Really your mileage went up? That would be nice, I might go that way then. Thanks for the input.

So this cam instead.

Cam:
Comp Cam 212/218 115lsa low lift (.558 .563)
+supporting valve train stuff (springs, etc.)

The reason I am going with a smaller cam is I want it to idle like stock and so I can tune it myself. IMO learning to tune is going to be a challenge anyway so tuning a smaller cam from the begining IMO would be easier.

moes04silverado

iTrader: (2)

i gain on fuel mileage also!!! went from 15/16 on the highway to 18-20

here are my cam specs

Thunder Racing

224/224 .581/.581 112lsa

BLACKND

iTrader: (5)

I third the 4.10's. I had 3.90's in my crew cab and always wished I had gone to the next size. Besides, what brand 3.90s were you looking at. IMO the richmonds are too noisy, I hated mine. And why not go with the same cam on a 112 LSA? Or Comp makes a custom grind 214/220 .559/.564 lift and 112 LSA that I think would be great on the 4.8 or even the comp 216/220