Comp Cams Camshaft And GM Performance Intake Manifold

The new cylinder heads also require a different carbureted intake manifold because of the wider but shorter intake-port design. GM Performance Parts has already filled that void with a brand-new casting.
The new cylinder heads also require a different carbureted intake manifold because of the
The cam change to the Comp Cams hydraulic roller was again, very easy, and we reused the production GM hydraulic roller lifters.
The cam change to the Comp Cams hydraulic roller was again, very easy, and we reused the p
This is the plenum area of the new GMPP intake manifold. Most modern single-plane intakes tend to extend the port-runner dividing walls into the plenum area. This manifold does not. We might experiment with this to see if there is some power hiding in this manifold.
This is the plenum area of the new GMPP intake manifold. Most modern single-plane intakes

Dyno Day
Test 1: is the best power curve from last month's story using the stock LQ4 6.0L iron heads, GMPP Hot cam, GMPP carbureted intake manifold, Holley 750-cfm carb, and Kooks 1-3/4-inch headers. Test 2: is where we jump directly to the big L92 heads combined with the larger Comp hydraulic roller camshaft. We also increased carburetor size to an 850-cfm Holley to make a little more power at the top while retaining the Kooks 1-3/4-inch headers.
	Test 1		Test 2		DIFF
RPM	TQ	HP	TQ	HP	TQ	HP
2,200	399	168	378	157	-21	-11
2,400	392	179	378	172	-14	- 7
2,600	393	194	386	191	-7	-3
2,800	401	214	396	211	-5	-3
3,000	414	237	406	232	-8	-5
3,200	427	260	414	253	-13	-7
4,300	435	281	419	271	-16	-10
3,600	438	299	422	289	-16	-10
3,800	437	315	423	305	-14	-10
4,000	434	331	424	323	-10	-8
4,200	434	347	427	341	-7	-6
4,400	436	366	432	362	-4	-4
4,600	441	387	438	385	-3	-2
4,800	447	408	447	408	0	0
5,000	450	428	455	434	+5	+6
5,200	450	444	462	457	+12	+13
5,400	444	456	464	478	+20	+22
5,600	436	466	464	494	+28	+28
5,800	430	475	459	506	+29	+31
6,000	423	483	451	515	+28	+32
6,200	--	--	443	524	--	--
6,400	--	--	438	535	--	--
6,600	--	--	435	546	--	--
6,800	--	--	425	551	--	--
Avg.	428	336	427	364
Power/ci(peak)	1.23	1.32	1.27	1.51
Comparing peak numbers, the torque gained only 14 lb-ft, but the horsepower jumped a staggering 68 hp with the combination of the larger cam and the L92 heads.

SOURCES
COMP Cams	Kooks Custom Headers North Bayshore NY 866-586-5665 www.kookscustomheaders.com
Federal-Mogul 26555 Northwestern Hwy. Southfield MI 48034 248-354-7700 www.federal-mogul.com	LKQ Chicago IL
GM Performance Parts www.gmperformanceparts.com	Scoggin-Dickey Parts Center Lubbock TX N/A www.sdparts.com
Holley Performance Products 1801 Russellville Rd. Bowling Green, KY 42101 KY 42101 270-782-2900 www.holley.com