T-Rex and Ported Heads
Thread Starter
Joined: Aug 2004
Posts: 11,258
Likes: 146
From: Pace, FL
T-Rex and Ported Heads Hi, I'm a newb to the forums but I've searched for results on the T-Rex cam with ported heads on a stock shortblock and haven't found much. So, I have a couple of questions about what I'm considering.
I want a pair of heads that have high compression, but don't require milling, because of PtV clearance issues with the T-Rex. Also, I'll be installing all of this myself, and I can flycut the pistons if I have to, but I don't want to resurface deck for the intake manifold. Anyway, two heads that seem to fit the bill for my needs are the TEA Stage 3 5.3L Heads (I believe 10.9:1 CR, and it flows 320cfm and 276!)
and the Patriot Stage 2 LS6 Style Heads with 59cc welded chambers (11.5:1 CR and 304cfm and 229).
The TEA heads flow better on the top end, but it has lower compression, and large valves, 2.055" and 1.6, which will probably require some flycutting. The Patriot heads have a higher compression, better low and midrange flownumbers, smaller valves that probably won't require flycutting, but not the same topend flow.
Price is somewhat of a concern, with the TEA heads with Comp 921 springs, which I can easily replace after the T-Rex wears them out, should run over $2500 with 5.3L cores. The Patriot heads with the Patriot Gold Dual Springs are $1795 from TSP. However, I'm wanting to go with the head that will augment the T-Rex the best.
It seems to me that the TEA would agument it best because of the T-Rex's high lift and high RPM nature. If matched with a FAST 90mm Intake Manifold and Kooks 1-7/8" headers, the engine should produce very high numbers in excess of 510rwhp with all the bolt ons. What do you guys think? I like the Patriot heads because of the higher compression and lower price. It also seems that it flows well enough. However, I'm not too concerned with low RPM power, but good midrange torque would be nice. Patriot heads have pretty good velocity with its 225cc intake ports. I don't know what the intake port of the TEA heads are or its velocity, so I don't know how it'll do with midrange torque.
Alternatively, the ported AFR heads from Absolute and TEA seem to have great flow numbers. Yet can I get the combustion chambers welded in AFR heads, or is milling the only way to go? Absolute heads have 206cc intake ports and flow 320cfm @ .600
Those things should absolutely rock for a 3.9" bore! I haven't heard anything on TEA's AFR heads on a 3.9" bore 
If I have to mill the AFRs down to get 59cc combustion chambers, the T-Rex will get grumpy, and I'll have pistons bitchslapping valves. If Absolute welds chambers, then I might have to go with them when they are released.
I want a max effort 346 for now, and eventually I'll forge the bottom end and put a 150 shot of NOS on it, but for now I just want the best head/cam package I can buy. If any of you guys have any thoughts or knowledge of what might be best for what I'm looking for, I'd highly appreciate it.
Jake
I want a pair of heads that have high compression, but don't require milling, because of PtV clearance issues with the T-Rex. Also, I'll be installing all of this myself, and I can flycut the pistons if I have to, but I don't want to resurface deck for the intake manifold. Anyway, two heads that seem to fit the bill for my needs are the TEA Stage 3 5.3L Heads (I believe 10.9:1 CR, and it flows 320cfm and 276!)
and the Patriot Stage 2 LS6 Style Heads with 59cc welded chambers (11.5:1 CR and 304cfm and 229). The TEA heads flow better on the top end, but it has lower compression, and large valves, 2.055" and 1.6, which will probably require some flycutting. The Patriot heads have a higher compression, better low and midrange flownumbers, smaller valves that probably won't require flycutting, but not the same topend flow.
Price is somewhat of a concern, with the TEA heads with Comp 921 springs, which I can easily replace after the T-Rex wears them out, should run over $2500 with 5.3L cores. The Patriot heads with the Patriot Gold Dual Springs are $1795 from TSP. However, I'm wanting to go with the head that will augment the T-Rex the best.
It seems to me that the TEA would agument it best because of the T-Rex's high lift and high RPM nature. If matched with a FAST 90mm Intake Manifold and Kooks 1-7/8" headers, the engine should produce very high numbers in excess of 510rwhp with all the bolt ons. What do you guys think? I like the Patriot heads because of the higher compression and lower price. It also seems that it flows well enough. However, I'm not too concerned with low RPM power, but good midrange torque would be nice. Patriot heads have pretty good velocity with its 225cc intake ports. I don't know what the intake port of the TEA heads are or its velocity, so I don't know how it'll do with midrange torque.
Alternatively, the ported AFR heads from Absolute and TEA seem to have great flow numbers. Yet can I get the combustion chambers welded in AFR heads, or is milling the only way to go? Absolute heads have 206cc intake ports and flow 320cfm @ .600
Those things should absolutely rock for a 3.9" bore! I haven't heard anything on TEA's AFR heads on a 3.9" bore If I have to mill the AFRs down to get 59cc combustion chambers, the T-Rex will get grumpy, and I'll have pistons bitchslapping valves. If Absolute welds chambers, then I might have to go with them when they are released. I want a max effort 346 for now, and eventually I'll forge the bottom end and put a 150 shot of NOS on it, but for now I just want the best head/cam package I can buy. If any of you guys have any thoughts or knowledge of what might be best for what I'm looking for, I'd highly appreciate it.
Jake 
Thread Starter
Joined: Aug 2004
Posts: 11,258
Likes: 146
From: Pace, FL
Ya, I've seen that one, but I'd prefer not to flycut the **** out of my pistons if at all possible. I guess my question could be shortened. Is there a set of welded chambered heads that flow very well that would match up with the T-Rex? APE and Patriot are the only two that I know of that use LQ9 heads then weld the chambers for higher compression on a 3.9" bore. Both of those are below 2k also.
Joined: Nov 2001
Posts: 8,484
Likes: 0
From: Cecil County Raceway!!!
The problem with ported heads is that they typically come with larger valves.
My heads are milled .040 so I think you can effectively subtract these numbers.
on the exhaust side I measured .040...need .100 min
on the intake I measured ~-.040 or so...(.040 into the flycut) need .060 bare min
Either way it looks like you'll have to flycut the intake definately (with 2.02 valves) and maybe the exhausts
One other thing to consider...better make sure the cam is installed at the right intake centerline...if its advanced any...the intake clearance will get that much tighter. The numbers above are on a 107.5 centerline (+2 degrees advanced as per the cam spec sheet)
My heads are milled .040 so I think you can effectively subtract these numbers.
on the exhaust side I measured .040...need .100 min
on the intake I measured ~-.040 or so...(.040 into the flycut) need .060 bare min
Either way it looks like you'll have to flycut the intake definately (with 2.02 valves) and maybe the exhausts
One other thing to consider...better make sure the cam is installed at the right intake centerline...if its advanced any...the intake clearance will get that much tighter. The numbers above are on a 107.5 centerline (+2 degrees advanced as per the cam spec sheet)
