how you you verify cam specs?
Thread Starter
Drifting
Joined: Apr 2003
Posts: 1,379
Likes: 4
From: rome ny
how you you verify cam specs?
i bought a good used zz409 cam. from what i see it is a small base circle cam. what is the best way to verify the lift and duration of this cam once installed in the car. i tried to measure the valve open and closed to get total lift but a didnt have a mic and the lifters didnt have pressure built up yet, so i got false reading. it is really hard to eyeball a cam and see lift differences. is there an easier way?
Thread Starter
Drifting
Joined: Apr 2003
Posts: 1,379
Likes: 4
From: rome ny
the reason i was asking was that i didnt think the lift was as much as the stock cam, but the lobes are much steeper and definatly has more overlap. the fact that it is a small base circle cam might make just looking at the lift not very accurate. i just hate to get everythingput together and find out it is the wrong cam. i know the tpis part # is engraved in the front, so it is probably the right one. maybe im a little paraniod. 
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Well, you could just measure the base circle of each and you would know how much more lift the TPIS has.
The lobe peaks must be the same heght to clear the bearing holes, right, so more lift comes from a smaller dia base circle. A pair of calipers (not expensive from Sears) will be accurate enough.
The lobe peaks must be the same heght to clear the bearing holes, right, so more lift comes from a smaller dia base circle. A pair of calipers (not expensive from Sears) will be accurate enough.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by mos90
i just hate to get everythingput together and find out it is the wrong cam. i know the tpis part # is engraved in the front, so it is probably the right one. maybe im a little paraniod.
RACE ON!!!
Thread Starter
Drifting
Joined: Apr 2003
Posts: 1,379
Likes: 4
From: rome ny
Originally Posted by CFI-EFI
Degreeing the cam is a good idea whether you have suspicions or not. It verifies your work and that there isn't a stack up of tolerances that put it "off the mark". You don't have to wait until, "everythingput together", to check it. All you have to install is the cam, lifters, and timing set. Then if you find anything not to your liking, you are at the prefect place to rectify it.
RACE ON!!!
RACE ON!!!
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by mos90
seems like a good idea. i will pick up a degree kit tomarrow and check it out.
I had a ZZ9 done at Dennis Wells" Racing for $25
Jake
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by mos90
the only thing with degreeing the cam is you will find out what is it is installed at but it wont tell you specs of the cam.
RACE ON!!!
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Since the engine is in the car you may need to fab up a smaller degree wheel. Then a dial indicator is all you will need to spec out the cam.
Can you use a square rod in a drill through the dist opening spin up the oil pump to lube the lifters or is it an LT1? Are you trying to measure lift at the tip of the push rod with the rocker off?
Can you use a square rod in a drill through the dist opening spin up the oil pump to lube the lifters or is it an LT1? Are you trying to measure lift at the tip of the push rod with the rocker off?
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by mos90
yes...you cant verify lift and duration with degreeing as far as i was told..
RACE ON!!!
