typical road race cam profiles?
06-16-2005, 04:00 PM
#1
typical road race cam profiles? Hey guys... I'm getting more and more into road racing and looking at replacing my cam with something smaller I believe.
Here is my combo:
439rwhp/385rwtq
'99 shortblock with Katech rod bolts 23K miles
AFR 205's milled .024", MLS gaskets
TSP 233/239 .603/.600" 112LSA cam
LS6 intake, ported TB
March UD pulley, Fidanza alum flywheel, T56
Jagsthatrun (JTR) 1 7/8" LT headers, Magnaflow dual 3" with cats/Xpipe/muffs
3:90 gears thru RX-7 IRS with alum driveshaft
no p/s or a/c
91 octane, 26* timing
This cam when compared to my buddies 225/225 .589" lift cam made 40rwtq less at 2500-3500rpm and about 20-30rwtq less from 3500-4500rpm with nearly identical mods (I have AFR's and he has Stage 3 GTP 5.3 heads being the only difference aside from the cam). Only at 6200rpm did my cam finally more power than his and only a few percent more. He made 428rwhp/405rwtq..... I only rev my cam to about 6,000 on the road courses to keep coolant temps down and when passing to 7100rpm if needed.
On the road course I can blow the tires off in 2nd when exiting corners if I try... but most of my corners require 3rd gear and traction is good. I have 285/30/18 Mich Pilot Sport Cup tires I'm running all around and once these wear out some Hoosier R3S03's same size.
What cam are you guys running and what do you think about me running a 224/228 cam? I can get a used one for $200. I think the powerband won't be as high and I'll gain a little more torque back.
Other mods are in my sig. I have 3:90 gears.
Here is my combo:
439rwhp/385rwtq
'99 shortblock with Katech rod bolts 23K miles
AFR 205's milled .024", MLS gaskets
TSP 233/239 .603/.600" 112LSA cam
LS6 intake, ported TB
March UD pulley, Fidanza alum flywheel, T56
Jagsthatrun (JTR) 1 7/8" LT headers, Magnaflow dual 3" with cats/Xpipe/muffs
3:90 gears thru RX-7 IRS with alum driveshaft
no p/s or a/c
91 octane, 26* timing
This cam when compared to my buddies 225/225 .589" lift cam made 40rwtq less at 2500-3500rpm and about 20-30rwtq less from 3500-4500rpm with nearly identical mods (I have AFR's and he has Stage 3 GTP 5.3 heads being the only difference aside from the cam). Only at 6200rpm did my cam finally more power than his and only a few percent more. He made 428rwhp/405rwtq..... I only rev my cam to about 6,000 on the road courses to keep coolant temps down and when passing to 7100rpm if needed.
On the road course I can blow the tires off in 2nd when exiting corners if I try... but most of my corners require 3rd gear and traction is good. I have 285/30/18 Mich Pilot Sport Cup tires I'm running all around and once these wear out some Hoosier R3S03's same size.
What cam are you guys running and what do you think about me running a 224/228 cam? I can get a used one for $200. I think the powerband won't be as high and I'll gain a little more torque back.
Other mods are in my sig. I have 3:90 gears.
06-21-2005, 06:48 PM
#2
Be careful with the "off the shelf" LS1 cams. Especially the big ones. The ramp rates on the lobes are brutally fast and will eat your valvetrain alive. There are only 2 cams designed for the LS1 that were meant for road race use. The ASA cam and the Grand Am Cup cam. You wont see the peak #'s with these cams like you do with the others, what you will see is oodles of power "under the curve". Most Ls1 cams are "peaky". These ones are not. They both have big duration, narrow LSA and decent lift. I dont know about he ASA cam but the GAC has an asymetrical lobe profile. Alot softer on the valve train.
06-21-2005, 09:15 PM
#3
TECH Addict
It sounds to me like the ASA cam would be a very good choice for you. I've had mine in my car for a month or so and so far I love it. It'll easily make power to 6500+ rpm's and great torque even from 2500 rpms's. The valve train is just as quiet as it was with the stock cam. You could easily run 1.8 rockers as well to add some lift if you wanted to. I'm going to leave mine as is though. Lot's of twist in the area's you're running yours in for sure. A custom cam might also be an option you might like to look into.
