new heads vs old heads
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Pro
Joined: Jan 2004
Posts: 525
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From: Morton IL
new heads vs old heads
I have some A.R.E. Stage II LS6 heads on my 01 zo6. They have 2.08 1.60 valves, and flow...
200 155.9 136
300 212.3 171.9
350 235.5 186.3
400 258.8 193.4
450 280.3 202.4
500 293.6 213.2
550 301.9 218.5
600 311.8 227.4
I am running a comp cam XE-R 232/236 .595/.601 @ 114 lsa. It has a PP TB, port matched ls6 intake, stock pulley, stock airbridge, TPIS through cats, GHL exhaust and Donaldson Blackwing.
The car dyno'd 420.5/389 SAE yesterday.
The numbers seem to flow very well, but I'm not sure they huge intake valve is doing much for the heads in terms of velocity, which is very important. Would it be worth switching to a 'new' patriot ls6 head (or really whoever), ie could I pick up 20-30 hp more? To me, a heads/cam ls6 should be doing higher than 420.
200 155.9 136
300 212.3 171.9
350 235.5 186.3
400 258.8 193.4
450 280.3 202.4
500 293.6 213.2
550 301.9 218.5
600 311.8 227.4
I am running a comp cam XE-R 232/236 .595/.601 @ 114 lsa. It has a PP TB, port matched ls6 intake, stock pulley, stock airbridge, TPIS through cats, GHL exhaust and Donaldson Blackwing.
The car dyno'd 420.5/389 SAE yesterday.
The numbers seem to flow very well, but I'm not sure they huge intake valve is doing much for the heads in terms of velocity, which is very important. Would it be worth switching to a 'new' patriot ls6 head (or really whoever), ie could I pick up 20-30 hp more? To me, a heads/cam ls6 should be doing higher than 420.
Burning Brakes
Joined: Jul 2003
Posts: 1,104
Likes: 0
From: "In a van down by the river" CO
Re: new heads vs old heads (wango tango)
That does seem low, depending on the dyno you used. 2c5only21 is getting about 430 on a 99 LS1, MN6 w/ stage 2.5 and the TR224 through a Donaldson and Belanger exhaust. :confused:
Drifting
Joined: Nov 2001
Posts: 1,791
Likes: 0
From: NE PA
Re: new heads vs old heads (wango tango)
Assuming your motor is properly tuned, those heads are killing you. Several cars with slightly smaller cams are making 440+ rwhp with the heads in my signature. If my car were an M6, I'd have likely broken the 400 rwhp mark even the little cam I'm running.
[Modified by XTrooper, 6:05 AM 2/2/2004]
[Modified by XTrooper, 6:05 AM 2/2/2004]
Melting Slicks
Joined: Jun 2001
Posts: 2,743
Likes: 3
From: Davie Florida
Re: new heads vs old heads (wango tango)
I think you are right, that 2.08 intake valve is probabily hurting your cars output, because of shrouding around that big valve. A valve that big belongs on a set of heads for an engine with a 4 inch or larger bore. Are you sure those heads weren't meant to be used on a large displacement engine. How does your car perform at the track? That's what really counts anyway.
[Modified by Mitch C, 12:37 PM 2/2/2004]
[Modified by Mitch C, 12:37 PM 2/2/2004]
Drifting
Joined: Nov 2001
Posts: 1,791
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From: NE PA
Re: new heads vs old heads (wango tango)
P.S.- Understand that the Patriot "LS6" heads aren't LS6 heads. They are truck heads with the combustion chambers welded up to make them smaller. I'm not implying this is a bad thing, just wanted you to understand what you were buying if you decide to go that way. :)
Melting Slicks
Joined: Oct 2002
Posts: 2,855
Likes: 0
Re: new heads vs old heads (XTrooper)
:iagree: the guy that built my heads has examined these heads and was not at all impressed--on one set he could see daylight between one of the valves and the seats, I would examine them carefully, and the porting appears to leave something to be desired, and I also agree about the valves, I'm not sure you should even be using 2.055 on stock displacement, I would use the 2.02/1.57 and the VE should give you what you are looking for, perhaps you should sell those on the forum and do a P&P on a new set using the stock valve sizes--
