Chevy High Performance Magazine
Intake Port Flow Test Results
180cc to 199cc Heads

Valve Lift	Airflow Research 190	Brodix-8 Pro	Canfield Aluminum	Holley SysteMAX	GM LT4	Edelbrock Performer*
.200	144	125	141	130	147	121
.300	208	177	201	184	197	174
.400	244	220	247	222	230	216
.500	262	254	258	242	250	235
.600	261	226	257	252	243	236
*The Edelbrock head has a 166cc port volume; but is included here because it competes directly with these other aftermarket heads in the marketplace.

Chevy High Performance Magazine
Exhaust Port Flow Test Results
180cc to 199cc Heads

	Airflow Research 190		Brodix -8 Pro		Canfield Aluminum		Holley SysteMAX		GM LT4			Edelbrock Performer*
Valve Lift	open	w/pipe	open	w/pipe	open	w/pipe	open	w/pipe	open	w/pipe		open	w/pipe
.200	115	121	91	94	104	107	90	92	109	114		95	96
.300	146	157	118	123	135	143	117	122	133	141		134	134
.400	176	188	138	144	164	175	143	148	159	167		159	159
.500	190	202	155	164	175	190	168	172	172	180		177	177
.600	197	211	161	170	183	200	181	187	177	185		187	187
*The Edelbrock head has a 166cc port volume; but is included here because it competes directly with these other aftermarket heads in the marketplace.

"Pipe Dreams"

One of the most recent changes in cylinder-head flow-testing is the use of an exhaust pipe. The idea is to better simulate the way the exhaust port flows air. Our testing revealed that there is a significant difference in exhaust port flow when the same port is flowed with and without a pipe...Higher lift numbers tended to reflect the greatest change in flow between using the pipe and not using it. Increases were around 4 to 7 percent with the addition of the pipe."

AFR 210cc Race Ready Heads
Out-flow Every Challenger!

AFR Race Ready Cylinder Heads

Here's what CHP has to say about AFR's 210cc Aluminum Race Ready Heads: "When you get into these larger heads, the flow really starts to take off. The AFR heads measured a little larger than 210cc, but when you've got 240 cfm at 0.400-inch valve lift, who cares? The AFR 210 rocked to a max flow of 284 cfm at 0.700-inch valve lift right out of the box. With its E/I of 75 percent at 0.400-inch valve lift, it's hard to find something wrong with these heads. As street heads they're probably a bit large for a 350ci small-block, but they'd be a killer for a larger displacement Mouse motor, such as a 408- or 420ci thumper. When it comes to airflow, especially around 0.400- and 0.500-inch valve lift, the AFR is unparalleled among the heads we tested."