Best heads for lq9
TECH Veteran
Joined: Sep 2014
Posts: 4,893
Likes: 703
From: Mississippi
*Referring to HOT Rod mag article of 20 intakes tested. A PROVEN head on a 370ci is a out the box AFR 230 V2 head. Combined with headers acourse and a FAST 102mm the motor pumped out 590 horse at the crank using a cam that wasn't really optimized for the heads and intake. It was a poor cam choice at 231/247 duration comp shelf cam. Due to the AFR heads having such a high intake to exhaust you don't need so much exhaust duration on the cam. To clear 600 horse I would follow this combo but with slight twists yet not to spend money on unessarary stuff.
- Run the AFR heads out the box.. no additional work is needed to the heads. Ported heads by Tony Mamo is high.
- instead of just bolting the intake on the motor out the box I would have the intake ported to match the heads by Tony Mamo.
- instead of choosing a comp off the shelf cam I would let Tony Mamo or Pat G spec the cam using a cam motion core.
Follow this setup here and I do what I recommended and you'll clear the 600 Mark easliy with good drivabilty and a mean low end grunt to boot.
I pesonally think a 234/238 cam would be more powerful than the cam Richard used in the article.
- Run the AFR heads out the box.. no additional work is needed to the heads. Ported heads by Tony Mamo is high.
- instead of just bolting the intake on the motor out the box I would have the intake ported to match the heads by Tony Mamo.
- instead of choosing a comp off the shelf cam I would let Tony Mamo or Pat G spec the cam using a cam motion core.
Follow this setup here and I do what I recommended and you'll clear the 600 Mark easliy with good drivabilty and a mean low end grunt to boot.
I pesonally think a 234/238 cam would be more powerful than the cam Richard used in the article.
TECH Fanatic
Joined: Aug 2009
Posts: 1,845
Likes: 255
From: Coast of San Mateo County Between Pacifica & HMB
I agree with you Darth, as I mentioned before, MMS 235s
(out of the box, maybe lighter valves) would be
An awesome head for a 4.00"-4.060" Bore especially with the
3.625" Stroke.
Tusky I believe what you ment to say was the AFR 230 (and MMS235)
have much higher "Exhaust to Intake Ratio"
227*-231* intake duration is the sweet spot for a 3.625" Stroke IMO
From 1500-7000RPM and naturally aspirated, only 4*-6* split
Need to be added to exhaust duration due to the excellent
E/I Ratio. LSA and advance determined by Tony based on
Induction, weight, gearing, trans, and goals/purpose.
(out of the box, maybe lighter valves) would be
An awesome head for a 4.00"-4.060" Bore especially with the
3.625" Stroke.
Tusky I believe what you ment to say was the AFR 230 (and MMS235)
have much higher "Exhaust to Intake Ratio"
227*-231* intake duration is the sweet spot for a 3.625" Stroke IMO
From 1500-7000RPM and naturally aspirated, only 4*-6* split
Need to be added to exhaust duration due to the excellent
E/I Ratio. LSA and advance determined by Tony based on
Induction, weight, gearing, trans, and goals/purpose.
If you want 500-600hp out of a 365" engine you're going to need incredible cylinder head flow out of an efficient port. You'll also need compression and enough available p to v to run a large enough camshaft to make the HP you're after.
You'll have to fly-cut the pistons for the camshaft you'll need to run and to have adequate P to V. IMO the compression will need to be at least 11.5:1 to reach your goals which will require the heads to be milled and milling takes away P to V clearance.
I'd go with a proven head like a TFS or AFR head. You can get these direct from the manufacturer for a cheaper price, or have someone like Chris Frank or Tony Mamo port a set themselves. They'd buy the heads as a raw casting with no port work performed, and then port them themselves to their liking. This costs more, but you end up with a head that flows considerably more air and is even more efficient.
I have a few ideas in terms of what kind of camshaft it would take to reach your goals, but everything has to work together in a build like this to make the kind of power you're after.
It would be much easier honestly if you just purchased a 408" rotating assembly to reach your 600hp goal IMO.
You'll have to fly-cut the pistons for the camshaft you'll need to run and to have adequate P to V. IMO the compression will need to be at least 11.5:1 to reach your goals which will require the heads to be milled and milling takes away P to V clearance.
I'd go with a proven head like a TFS or AFR head. You can get these direct from the manufacturer for a cheaper price, or have someone like Chris Frank or Tony Mamo port a set themselves. They'd buy the heads as a raw casting with no port work performed, and then port them themselves to their liking. This costs more, but you end up with a head that flows considerably more air and is even more efficient.
I have a few ideas in terms of what kind of camshaft it would take to reach your goals, but everything has to work together in a build like this to make the kind of power you're after.
It would be much easier honestly if you just purchased a 408" rotating assembly to reach your 600hp goal IMO.
LS1Tech Sponsor
Joined: Sep 2004
Posts: 825
Likes: 568
That's a HUGE spread in power and the parts and money required are very different also.
Same size engine with similar compression, 100 HP naturally aspirated is a huge difference.
My out of the box MMS 235's would run great and likely get you towards the higher end of your target but the right complimenting components is of course key and required. Have me port the 102 is another no brainer....go with a mdium sized stick for a better balanced combo....numbers aside you will enjoy it for a long time versus getting too aggressive and chasing a number only to get tired of all the trade-off that come with that decision long term.
I can guide you into the right package.....when your up for putting something together shoot me a PM or better yet an email and we can discuss whats involved. Ive built countless successful combinations over the years and know how to optimize the money you (we) have to work with.
Cheers,
Tony
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Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
www.mamomotorsports.com
Tony@MamoMotorsports.com
Anything worth doing is worth doing well. Build it right the first time....its alot cheaper than building it twice!!
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Teching In
Joined: Sep 2020
Posts: 16
Likes: 0
*Referring to HOT Rod mag article of 20 intakes tested. A PROVEN head on a 370ci is a out the box AFR 230 V2 head. Combined with headers acourse and a FAST 102mm the motor pumped out 590 horse at the crank using a cam that wasn't really optimized for the heads and intake. It was a poor cam choice at 231/247 duration comp shelf cam. Due to the AFR heads having such a high intake to exhaust you don't need so much exhaust duration on the cam. To clear 600 horse I would follow this combo but with slight twists yet not to spend money on unessarary stuff.
- Run the AFR heads out the box.. no additional work is needed to the heads. Ported heads by Tony Mamo is high.
- instead of just bolting the intake on the motor out the box I would have the intake ported to match the heads by Tony Mamo.
- instead of choosing a comp off the shelf cam I would let Tony Mamo or Pat G spec the cam using a cam motion core.
Follow this setup here and I do what I recommended and you'll clear the 600 Mark easliy with good drivabilty and a mean low end grunt to boot.
I pesonally think a 234/238 cam would be more powerful than the cam Richard used in the article.
- Run the AFR heads out the box.. no additional work is needed to the heads. Ported heads by Tony Mamo is high.
- instead of just bolting the intake on the motor out the box I would have the intake ported to match the heads by Tony Mamo.
- instead of choosing a comp off the shelf cam I would let Tony Mamo or Pat G spec the cam using a cam motion core.
Follow this setup here and I do what I recommended and you'll clear the 600 Mark easliy with good drivabilty and a mean low end grunt to boot.
I pesonally think a 234/238 cam would be more powerful than the cam Richard used in the article.
Staging Lane
Joined: Feb 2020
Posts: 80
Likes: 19
I just dyno'd 442 the other day through an auto with an ambient temperature of 82 degrees. I'm running a LQ9, stock untouched LS3 heads, GPI ported LS3 intake, ported LS2 TB, and a 227/236 cam. You'll need a lot more head/cam/compression than I have to hit 500 wheel NA.
Teching In
Joined: Sep 2020
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TECH Veteran
Joined: Sep 2014
Posts: 4,893
Likes: 703
From: Mississippi
Richard Holderner made 591 horses on a forged 6.0 with a off the shelf comp 231/239 cam with a fast 102mm intake and AFR 230 V2 heads.
To actually clear 600 at the crank go just a little bigger than the cam above and it should make it but torque number might surfer from doing so.
To actually clear 600 at the crank go just a little bigger than the cam above and it should make it but torque number might surfer from doing so.
Remember you won't make that power with torque on a 6.0. You'll make it with RPM. If you don't care about driveability, then cam fairly aggressively, say 242/246-111+3 territory and 12.1 compression. If you go solid roller, add five degrees to both sides. Be a **** on your valvetrain geometry - set the rockers with proper wipe pattern, run 11/32 pushrods or open the holes up for 3/8.(even better). Set it up to peak around 6800 rpm with peak torque in the 5200-5400 range. Don't fall for the short runner / small plenum BS. Rod mod the LS3 intake or else do a fast long runner or even the hi ram type set up.
My point it, it ain't just about the cam, but those AFR 230's will certainly support the power. Set the motor up to rev and not float valves, and you'll do great.
My point it, it ain't just about the cam, but those AFR 230's will certainly support the power. Set the motor up to rev and not float valves, and you'll do great.
