Head and intake flow. Something to think about. :)

5ohCOUPE · 03-14-2003, 12:07 PM

Im getting a set of AFR 165's and an Edelbrock Performer RPM intake. The intake flows around 217 to 220 per runner, the heads flow 245 per intake runner. Will you really get the full power out of these heads if the intake is holding it back that much ???? I have heard that the intake should flow more than the heads. Any ideas on what can be done other than porting the intake or going with a different intake? Also these flow numbers were from 2 different sources. Its possible that the numbers might be WAY off and im just worrying for nothing. The holley systemax intake flows more but I think it might flow too much for a N/A combo. What do you guys think??

DirtKing · 03-14-2003, 02:23 PM

I wouldn't be afraid of the holley intake, however, i found that my afr 205's max ported flowed what AFR said they did box stock. Call up extrude hone and ask them what increases they see from porting the edelbrock. It's one good way to verify flow numbers from an independant source.

dragstang86 · 03-14-2003, 09:43 PM

im going to put the systemax on my N/a 306. I know a guy with canfield heads, x-303 and a systemax with a c-4 2800 stall convertor goin mid 11's. Go with the systemax or wait for the RPM 2 to be released at the end of april.

Jeff Chambers · 03-16-2003, 08:52 AM

A good basic rule-of-thumb is that you want the intake to flow 15% more than the heads so that the intake doesn't become the restriction in the airflow. I've found this to be a pretty good rule-of-thumb for getting the absolute maximum performance out of flow limited heads like we used to be forced to run in S/W. The performance difference between an intake that flows nearly what the heads did and one that had the 15%+ excess was significant.

03-14-2003, 12:07 PM	#1
5ohCOUPE Registered Member Join Date: Sep 2001 Location: ORANGE PARK FL. USA Posts: 208	Head and intake flow. Something to think about. :) Im getting a set of AFR 165's and an Edelbrock Performer RPM intake. The intake flows around 217 to 220 per runner, the heads flow 245 per intake runner. Will you really get the full power out of these heads if the intake is holding it back that much ???? I have heard that the intake should flow more than the heads. Any ideas on what can be done other than porting the intake or going with a different intake? Also these flow numbers were from 2 different sources. Its possible that the numbers might be WAY off and im just worrying for nothing. The holley systemax intake flows more but I think it might flow too much for a N/A combo. What do you guys think?? __________________ 91 LX COUPE, 3.73 gears, 2 1/2 inch H-Pipe, 1 5/8 MAC long tube headers, 73 MM C&L MAF, 70 MM MAC TB, LUNATI cam,1.7 TFS Rockers, TFS Track Heat heads, TFS Track Heat intake, T5 with PRO 5.0 shifter, Griffin aluminum radiator, Fluid Damper, SSM traction bars, 190 GPH in tank fuel pump. And more to come.

03-14-2003, 02:23 PM	#2
DirtKing Registered Member Join Date: Feb 1999 Location: brooklyn center,mn,USA Posts: 169	I wouldn't be afraid of the holley intake, however, i found that my afr 205's max ported flowed what AFR said they did box stock. Call up extrude hone and ask them what increases they see from porting the edelbrock. It's one good way to verify flow numbers from an independant source. __________________ 88LX notch, Speedpro EFI 358windsor 11.2 to 1 compression, 5 lug baer claws all around..g force t5 and 3.55 gears. rwhp soon to come. Oh yeah...92 octane NO detonation.

03-14-2003, 09:43 PM	#3
dragstang86 Registered Member Join Date: Sep 2002 Location: baltimore, md Posts: 220	im going to put the systemax on my N/a 306. I know a guy with canfield heads, x-303 and a systemax with a c-4 2800 stall convertor goin mid 11's. Go with the systemax or wait for the RPM 2 to be released at the end of april. __________________ 90 LX Hatchback 306, AFR 165's 58cc, E303, 1.6 roller rockers, 70mm throttle body, cobra intake, bbk fenderwell, bbk longtubes, x-pipe, flowmasters, pullies, msd 6a, crane ps-92, stock MAF sensor, electric fan, No AC, No air pump, flaming river quick ratio rack C-4, 3500 stall, 373's, aluminum driveshaft SSM Lift bars, , sub frame connectors, strut tower brace 12.57 @105.12mph w/ 1.686 60ft before bbk longtubes (with equal shorties) ----------------------------------------- 86 tube chassis coupe - the trailor queen

03-16-2003, 08:52 AM	#4
Jeff Chambers Moderator Join Date: Aug 2000 Location: Milan, OH Posts: 2,699	A good basic rule-of-thumb is that you want the intake to flow 15% more than the heads so that the intake doesn't become the restriction in the airflow. I've found this to be a pretty good rule-of-thumb for getting the absolute maximum performance out of flow limited heads like we used to be forced to run in S/W. The performance difference between an intake that flows nearly what the heads did and one that had the 15%+ excess was significant. __________________ Jeff Chambers 1990 Mustang GT 10.032 Seconds / 137.5 MPH 14-time Street Warrior World Record Setter CRT Performance 2001 Tropic Green Mustang GT - 12.181 / 113.2 MPH 2002 Ford F-250 Crew Cab 7.3l Power Stroke - 17.41@77.2 "There's nothing boring about a small block automatic shifting gears at 9400 rpm!"

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