Cam check
Thread Starter
Race Director
Joined: Aug 2004
Posts: 10,628
Likes: 132
From: Duvall, WA
Cam check
I'm acquiring parts for the 350 I'm building for my '71 Roadster and want to run a cam by my CF C3 people to see what you think.
http://cranecams.com/index.php?show=...21&lvl=2&prt=5
It's a four speed with 3.36 rear end, 10:1 compression, the new AFR 195 heads, forged pistons, forged steel GM crank, H beam connecting rods. The car will never see a track, I just want nice street performance. I think this cam is about right. Anyone else?
http://cranecams.com/index.php?show=...21&lvl=2&prt=5
It's a four speed with 3.36 rear end, 10:1 compression, the new AFR 195 heads, forged pistons, forged steel GM crank, H beam connecting rods. The car will never see a track, I just want nice street performance. I think this cam is about right. Anyone else?
Melting Slicks
Joined: Dec 2000
Posts: 3,407
Likes: 2
From: Carmichael CA
I'm looking at the list on this page: http://cranecams.com/index.php?show=...262-400%20C.I.
I see that the cam you selected is for a hydraulic roller rocker setup...is that what you are doing...adding a roller cam setup? Or, do you just want a better cam than what was in your L48?
I think you would be happier with the 268: http://cranecams.com/?show=browsePar...tType=camshaft or the 272: http://cranecams.com/?show=browsePar...tType=camshaft part numbers 113521 or 100052.
Hopefully, someone with a 71 who replaced their cam will chime in with their thoughts. But, there's also CompCams.com to look at...they have what they call Extreme Energy cams like the 262XE which is decent...or a plain 268H. Some owners that upgradded to the 272 Magnum have some rough idles. On descriptions of cams the idle will start with SMOOTH IDLE which means it actually idles at the required idle speed with good vacuum...around 15inHG. GOOD IDLE means if idles at a higher RPM than the required idle speed and has slightly less vacuum...around 12inHG...you can get these to idle at the required idle speed, but it will be a rough idle. Then there are the cams which don't even list that they idle...the specs have the minimum range at like 2400RPM...which is about where they "idle" at.
I see that the cam you selected is for a hydraulic roller rocker setup...is that what you are doing...adding a roller cam setup? Or, do you just want a better cam than what was in your L48?
I think you would be happier with the 268: http://cranecams.com/?show=browsePar...tType=camshaft or the 272: http://cranecams.com/?show=browsePar...tType=camshaft part numbers 113521 or 100052.
Hopefully, someone with a 71 who replaced their cam will chime in with their thoughts. But, there's also CompCams.com to look at...they have what they call Extreme Energy cams like the 262XE which is decent...or a plain 268H. Some owners that upgradded to the 272 Magnum have some rough idles. On descriptions of cams the idle will start with SMOOTH IDLE which means it actually idles at the required idle speed with good vacuum...around 15inHG. GOOD IDLE means if idles at a higher RPM than the required idle speed and has slightly less vacuum...around 12inHG...you can get these to idle at the required idle speed, but it will be a rough idle. Then there are the cams which don't even list that they idle...the specs have the minimum range at like 2400RPM...which is about where they "idle" at.
Drifting
Joined: Apr 2002
Posts: 1,716
Likes: 4
From: New Baden Illinois
I have a brand new Crane 272 Powermax cam and lifter kit if you are interested. It is the hydraulic flat-tappet, if you aren't going with the roller setup. This is supposed to be the largest cam that you can go with without increasing the stall speed.
Here is the link for the thread I have in the parts section:
http://forums.corvetteforum.com/show....php?t=1472969
Send me a pm if you are interested.
Here is the link for the thread I have in the parts section:
http://forums.corvetteforum.com/show....php?t=1472969
Send me a pm if you are interested.
Thread Starter
Race Director
Joined: Aug 2004
Posts: 10,628
Likes: 132
From: Duvall, WA
Yes, I am going to go with a roller set up. I am going to use a different block and save the original numbers matching engine. The block I am going to use has 4-bolt mains and factory bore. The machine shop verified it will clean up at .030 over. I don't need a whole lot of vacuum, as I don't have power brakes.
Also, it's a 4-speed so stall speed isn't an issue.
Also, it's a 4-speed so stall speed isn't an issue.
Racer
Joined: Nov 2004
Posts: 485
Likes: 1
From: Oakville ON
If you are looking for good street performance, I suggest you go with a cam with 222* - 226* if you want good low end an easy off-idle transition, while still being powerful. The 195 is bigger than what you want - go with the 180. Check out AFR's web page for power curves they show with which head and cam. Most people want too much cam /port for what they really need.
Race Director
Joined: Mar 2001
Posts: 11,322
Likes: 1
From: Living in the Hartland
Check out the GM Hot cam, am running it a 355 in my Formula and it makes loads of torq. I am running 1.5 rockers so the duration is about 2 less on both int and exh.
Can be had for about $200
This hydraulic roller cam is for service only for all V8 engines with roller camshafts. The duration at lash point in degrees (intake/exhaust) is 279/287; duration at .050" tappet lift (intake/exhaust) is 218/228; and maximum lift with 1.6 rocker ratio (intake/exhaust) is 525/525. Valve lash is zero/zero and lobe centerline is 112 degrees.
Le Mans Master
Joined: Oct 2001
Posts: 5,943
Likes: 3
From: Wildwood IL
Originally Posted by Rich's'78
Check out AFR's web page for power curves they show with which head and cam. Most people want too much cam /port for what they really need.
Look into "real" dyno'd builds to make a choice. That will give you an indication of real life numbers rather than a whole bunch of opinions & theory. Pretty surprising what head & cam combos AFR had dyno'd. Eddie
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
