I have a set of Stage2+ GTP heads off my T/A I could use on my 5.3L truck. The heads are milled and welded up to resemble the smaller chambers of a 5.3L head (they were made before people started using the 5.3L head cores). On a 5.7L engine I am supposed to see an 11.4:1 comp ratio. they flowed 317cfm intake @ .575 lift.

My question is would they be worth putting on the truck? Would it be ok to use my 02' Z06 cam or should I install the 223-.589-112 Piglet cam I have for those heads (if the gain would be marginal then I'd rather keep the Z06 cam for smog reasons). I don't see a lot of people with heads and cam in here so I just wondered if it was because of price or was it the gains are not worth it? My best ET to date with the new cam and electric fans is 14.60@91.75mph. I'd like to get into the lower 14s with the heads if possible so that the nitrous will get me into the high 12s. The truck weighs 4850lbs (track scale).

I also have a wet-kit I will be installing on the truck so I am aware of the fuel upgrades I'll have to do.

 

Okay... the only thing I see that may adversly effect this is the intake valve size...the 5.3 has a small 3.78" bore. I wouldn't go ANY larger than a 2" (I'd keep the stock 1.89" or maybe a 1.9") as you will shroud the chamber, decrease velocity, and lose power. Comp should be around or over 10.5:1 I'd say with those milled heads.

I'd run the Z06 cam +4*. It will be a total of 2* advanced then. That other cam is WAY too big with stock stall and no tuning.

Hope that helps...

 

Wait... read your sig. If you have that TT 3000 in there you could run that cam from your T/A but even then it's gonna need some mad tuning and head parts to hold up...springs, rods, retainers, etc.

What heads exactly to you have? 5.7s? What is the extent of their mods?

 

Hmm

I didn't want to change anything on the heads besides the springs because if I got in a pinch I could easily sell them. I believe they have 2.05 valves on them now.

The cam is almost identical to the TR224 but with more lift but still very fast ramp rate. The reason I was considering it is because my buddy put a 226/234 cam in his 6.0L and it kicks ***! He rules me at any speed and put down 332rwhp-346rwtq or something like that and the only diff. between us is his 6.0L vs my 5.3L and his bigger cam vs my 02' Z06.

I actually have a Yank TT3000 and LS1 Edit so tuning is no problem.

So most guys with trucks get them made with smaller vavles huh? Damn!

 

My heads are a stage 2+ (bigger than stage 2 but under a Stage3 race head). I bought them used from a guy who made 437rwhp-419rwtq in his T/A. I had issues in my T/A so i only made 370rwhp @ 5000rpm with this setup. They are machined for double springs, titanium retainers, I have 2 sets of hardended pushrods in 7.4 and 7.350 sizes.

I am not sure what all goes into doing LS1 heads but I know the chambers were welded up to make a smaller combustion chamber like the 5.3L heads, they were milled I am guessing .030 to get the extra compression ratio on a 5.7L. The ports were hand ported but not hogged out like ARE heads.

 

Damn F8LPONY...I'd sell my girlfriend to get those heads !!! (hmmm...not a bad idea actually...it would certainly be a renewable source of income )

I think those heads would be WAY too much fora 5.3...and with the 2.05 valves you would shroud the hell out of the them and probably end up nowhere near the real potential output of those heads


BTW...your friend runs a 226/234 in a 6.0 ??...with what kind of stall ??...and does it have ANY low-end left at all ???

 

Most of us truck guys are afraid of big cams compared to the f-bod guys.

I don't think anyone around here would think about putting that big of a cam in their truck. It may not be so bad with a 6.0, but in a 5.3 it would be rough.

 

LMAO at Yelo!!!

Yeah, that seems to be the general idea with the valves being too big I won't buy a set of heads for this truck so at worst I will just sell these and use the money for a blower or something.

I have a call in to Craig at GTP to see what he thinks it would cost to set these up for this truck but I doubt it would be worth the price.

As for the big cam in my buds truck you can actually read his post in this forum. His SN is BLK6.0LHD or something like that. The post was titled "My dyno #s or something".

I have drivin his truck around and while it seems to be a tinny bit more sluggish off the line than mine (He has a TCI 3200 stall) the damn things pulls VERY hard from 4k RPM all the way till his stock limiter. He had ZERO tuning at the time I drove it also. Even without tuning he leaves me in the dust. On my G-Timer he runs 96-97mph vs my 92mph (this timer has been used at the track and is almost dead on, less 1mph max).

Godamned 6.0L!!!!!

 

Man, the heads will make more power but not nearly as much as you are thinking. This 5.3 is a small motor...I bet those ports you could stick your fist into (not really but..) you will have not nearly enough cubes to pull that airflow and that intake valve is WAY too big for that bore. Velocity is power, more than total flow @ .650

It's not just the small displacement that needs that smaller valve, it's the bore...it's tiny! AFR-165cc SBF Ford heads have a 1.9" intake valve...that 302 motor comes with a 4" bore! That's due to cubic inch limitations not just bore. Why are those heads good for about 100flywheel HP (go read CarCraft within the last year)? High velocity ports and correctly sized valves. You are limited by both of those factors on the 5.3 when trying to use those heads on it. That'd be like using 205cc heads on the 302 motor...

 

224/232-558/568 on a 112. It lost alittle on the bottom before tuning and a stall, but not much. it would still spin the tires from a dead pretty good. After the converter and some tuning from Allen the thing wont hook in 2wd, it spins threw first and into sec without stalling it up on the converter. I have some videos that i will try to get on here.