mk3cn4

iTrader: (3)

Hey guys, I spent a lot of time on this so I really hope someone can use this video to determine simply if this is a stock or aftermarket camshaft.

I used a dial guage from Harbor Freight and had some confusing results measuring the lift on this cam.

Please see this very short video.

Is this enough to determine if this CAM is stock or aftermarket? (It's supposed to be a CheaTR cam).

Also attaching zoomed in pic of the guage at bottom.

First, here's the layout of what I did:



...and here's the video with the results:

Measuring Installed Cam

I still have it all set up, if I need to measure a different way I can.

Pics:



The video shows the pushrod going 238 thousandths "leaked down" on exhaust, is that enough info? Not sure what that means.


Guy who sold me the car said it has a CheaTR cam in it, someone in another post said if I did this I should be able to at least see that it's stock or not, that's all I'm really trying to determine at this point.

That thread:here where I'm trying to decide if the valvesprings need replaced or not. Answer from this thread will apply to decision in other thread.

outkast6991

iTrader: (34)

if it was me i would pull the rocker and try to measure off the pr itself. this will take the lifter plunger travel out of the equation. if it is .238 and we assume .100 of lifter travel it would put your lift around .575. no way to really be sure without taking the plunger travel out of the mix

99Bluz28

iTrader: (35)

Was this on the exhaust lobe? The lift on the CheaTR exhaust lobe at the valve spring is .575" so that sounds about right.
Id also try it off the valve spring retainer, you should be really close to .575" exh.
"CheaTR" - 214/230 .601/.575 117 LSA.

mk3cn4

iTrader: (3)

Yes, this was the exhaust lobe. Sounds like it may be a cheatr then. Will still do some more testing and post what I find.

Thanks !!!

mk3cn4

iTrader: (3)

Ok, this is cool. Someone had a good idea, I am going to go ahead and yank a rocker and check the pushrods and see if they are the stock ones, that would be a good indicator as well, and also do the same test above just on the unsprung pushrod.

Once I tell 100% it's a cheatr cam, then I'm back to my other thread (linked in first post) where I need to decide on swapping the springs because these look stock to me.

So, if the lift measurements continue to hold true at .575 showing it's a cheatr cam, and it's a stock pushrod, then I think I am going to assume the springs are stock and just buy springs for this thing to be safe I guess.

So I can shop while I continue to test, what springs do I need here assuming valvetrain is all stock 2002 LS1 (cheapest that are considered safe)? Do I need anything else, like special retainers or seats or whatever?

Thanks guys, I'm trying to learn about this stuff. Just so much to learn.

outkast6991

iTrader: (34)

depends if you want a single or dual spring. i would go with a PAC 1218 or 1518 and some hardened pr's for sure

farmington

iTrader: (14)

put your indicator on the valve side of the rocker arm to get your actual lift.

mk3cn4

iTrader: (3)

Cool, those 1218's are cheaper than I thought, I think I'll go with those.

Texas Speed site outright says they work with stock retainers and seats, so I assume that's all I need.

Since I'm an M6, I thought it was good practice to have stock pushrods because you want them to bend in case of an accidental too high downshift.

Now I need to find an in-car compressor I can borrow/rent!!!

I am still going to give the gauge another shot without the rocker before I reassemble to see if I can nail the cam specs with it, will post results here for other searchers.

Any other opinions or advice please chime in!!!

mk3cn4

iTrader: (3)

I didn't know that's where the measurement was supposed to be done, THANK YOU.. I will certainly do that. If it's very obvious and clear, maybe I'll make another video for other searchers.

Who knows, maybe it'll make a sticky here!!

Thanks.

EDIT: just realized the valve side drops when the valve opens, not sure if I'm going to be able to get the dial to work right there.

outkast6991

iTrader: (34)

i would stay off the rocker all together and just measure your lobe lift off the pr/lifter. take that number and multiply it by 1.7 and you have your valve lift

mk3cn4

iTrader: (3)

Yea, I think that's the best bet. I never knew what the actual lift numbers literally equated to on a cam, now I know! I will be doing that next chance I get, just going off of unsprung pushrod and multiply by 1.7

Thanks!!

EDIT: Got another good tip: I will do it on an intake pushrod, not exhaust, because intake is larger lift (on a cheatr cam) so it'll be even more obvious!

Please keep the tips coming!!!

01ssreda4

iTrader: (96)

No you do not want a stock pushrod because it will bend. Quite the opposite, with that cam they will bend, it's just a matter of time. You need aftermarket pushrods.