Do short runner intakes (i.e. MiniRam) like cams with more duration, or more lift? I am sure this is pretty technical. But I would think that with the short runners, the induction waves are packed together pretty tight, so wouldn't it make sence to run a higher lift cam, instead of a higher duration cam? I mean, if the waves are compact, then it seems as if having the valve open for a long time wouldn't help all that much, it makes sence to run more lift. Anyway, I really don't know about all this too well and was wondering if somebody could explain it to me.

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End

Current Mods: LT4 HOT Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Performance Resource Chip, Accel Ignition Coil, Cap, Rotor, 8.8mm Wires, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

Soon to Come: 7.625" 10 Bolt with 3.42s and Accel TPI Intake Base

 

yes

 

let me try this again before hitting reply. in short form, they are more preferred to longer duration as far as racing goes since short runners are for hp and that is mainly where higher rpm come's from is the duration. for street use, more lift is nice since short runners tend to have less torque.

 

both!!!!!!

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87z 383,afr 190's, comp hyd roller(242/248-.540/.562,114 sep),Ported and polished mini ram, 30lb inj, 3.42 gears, tremec 5spd, , 1,3/4" slp headers, speed pro bank to bank-wb02.
"Just remember children, no man can beat you once youv'e found the cliterous." 'chef'

 

Hey, 87Z-ya what are your times in the 1/4th and in 0 to 60?

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1987 Chevy Camaro IROC-Z
L98 TPI 350 (5.7L)
TH 700R-4 Transmission
Borg Warner 7.75" 9 Bolt Rear End

Current Mods: LT4 HOT Cam, Comp Cams 1.52:1 Roller Rocker Arms, Edelbrock TES 1 5/8" Headers, Hooker 3" Aerochamber Cat-Back System, Performance Resource Chip, Accel Ignition Coil, Cap, Rotor, 8.8mm Wires, K&N Filters, JET TPI Air Foil, All Free Mods, Falken ZIEX Z-Rated Tires.

Best ET (w/o LT4 cam): 14.32 @ 97.7mph
(corrected for elevation)

Soon to Come: 7.625" 10 Bolt with 3.42s and Accel TPI Intake Base

 

Both, and neither. The short runner intakes like the Mini-ram generally flow best at the upper rpm region, and high lift cams with large valves will help support the breathing habits of that type of intake. The duration of the camshaft is more important than the lift at determining the rpm range the cam works best at. I have a cam in my car with .500 lift on both intake and exhaust, but it also has a short stubby duration and therefore breathes best at very low rpms. Desktop Dyno shows me as having over 400 ft-lbs of torque at idle.

The real answer is that the intake/exhaust valve overlap is the most critical factor in determining the rpm range at which the cam works best, and since the overlap is a factor of both the duration and the LSA, and the duration numbers are most often spoken of in cam comparison discussions, the overlap becomes by default the variable everybody talks about. Larger amounts of overlap will breathe better at high rpms, and this will complement the short runner style intake the best.

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89 IROC with lots o' stuff

-=ICON Motorsports=-