Gannet

I just arranged to buy a custom Comp grind from forum bro 1stz06. Specs are 228/232 .588/.592, on a 110+1. Yes, another Patrick G grind.

This is going on a stock '02 LS1. Based on what I've read in other threads I get the impression this *should* clear if installed straight up, but I'd like other opinions. It's not a standard grind so it's hard to find equivalent examples.

Thanks in advance!

orangeapeel

iTrader: (18)

Always check if you are unsure. Always. But, I think that you will be fine with that cam. What type of lobes does it have? LSK/X-ER?

Gannet

I haven't seen the full cam card yet. But, given the specs it appears to be an XER 3724/3726 combo.

I'd check for sure if I was doing the install myself, but I am shopless. I'll have to see if any of the shops around here can do that without pulling the heads. You'd think so, but when I asked one repected shop about shimming the springs to within .050 of coil-bind I got the 'ol mumbo-jumbo. I almost get the impression a lot of these guys are just parts installers.

I dunno, maybe I'm unrealistic. I'd like to have my cam degreed, P to V checked, springs shimmed, and geometry checked. Is that too much to ask? How much should all that run, over and above the cost of an install? Do any shops do that, or only guys who are working on their own cars?

OTOH, I should think there would be a formula that would let you calculate clearance, if you knew the valve drop on a given setup, and had a reasonable approximation of the lobe lifts. Since practically all the cams of interest use Comp lobes it shouldn't be all that hard to amass a lobe table with lifts at say 10 or 20 degree increments. Interpolate what's in between. Any of you ME students out there up on your dynamics? Good extra-credit project.

orangeapeel

iTrader: (18)

Because for the most part that is true. You might rummage through the sponsor list and see if you are local to any of them. I know for a fact that there are several on there that will take good care of you.

PREDATOR-Z

Norris motorsport and VINCI

PTV will be fine on unmilled/stock gasket combo. Degreing this cam to make sure it is 110+1 is crutial (or doctor the thing to know if dot-dot is exactly that)
But, if cam only, I suggest advancing the cam another 2*
It will raise the DCR a tad (another .2 for ~ 8.2)

i would run 7.425 Comp cam p-rods

Josh

iTrader: (9)

Mine fit fine dot-to-dot.

Josh

BlackHawk T/A

iTrader: (3)

So instead of advancing the cam another 2*, how about he just gets it ground the right way and run it straight up? That is, if its not already in his hands.

PREDATOR-Z

He said that he is getting it used from another member.
BTW straight up means 0 advance like 110 LSA, 110 ICL
I think you meant dot-to-dot

Gannet

I did mean dot-to-dot, or 109 ICL in this case. Thanks for the correction. That's what I come here for, to learn.

I'm curious as to why you think longer pushrods would be a better fit in this case?

Mssingkid

iTrader: (7)

I have this cam(Being tuned on the 17th) and with a .045 gasket it cleared without issue. I wouldn't run a LSK on the exhaust side on this cam, as the piston chases the exhaust side. Intake valve has tons of room though and thats where my LSK lobe is. Hoping for 430hp and 400 trq with tons of power under the curve. I've done every bolton besides a FAST or EWP. I'm sure a FAST would net me some more power but i have to convince myself the 10-15hp is worth 1K...


227/232 .640/.595 110(+1) Again should have numbers 11/17/06..

PREDATOR-Z

Ok, just for ya, one more time

On a cam only swap, the XE-R lobes have a smaller base circle of at least .09x (depending on lifts). Half that amount is the effective amount needed to add to the stock length p-rods (7.400) to get back to the stock preload on lifters.
So ideally, the p-rods used should be 7.44x.
Now it is in general better not to go over that so the next logical smaller size is 7.425s
see Comp cam makes p-rods in .025 increaments. 7.325-7.350-7.375-7.400-7.425-7.50
I hope this makes sense. 7.425s will reduce the sewing machine effect normaly encountered with 7.400 on smaller lobes.

Gannet

Sure does. I was aware of the effect of base circle, I just didn't realize that XERs used a smaller base circle.

So now I'm curious why all the shops selling XER-based cam&kits are shipping 7.4s...

BlackHawk T/A

iTrader: (3)

Would a taller lifter make up the rest of the difference and let you nail it for no "sewing-machine" effect?

1stz06

iTrader: (18)

Gannet, there is a guy here named Pewterme. Do a search of his threads. He is running this cam with stock heads. He also had the cam installed dot-to-dot and then went back and had it advanced. I am sure he can pass along some useful information to you.

Best wishes,
J.R. Thomas

Gannet

J.R., thanks much for the pointers - and the cam. Checking through his many threads now.