schmendog

iTrader: (10)

Swapping out my big NA cam for a smaller blower cam next week and want to know if I can keep all the same valve train parts, or will I need to get different length pushrods etc. Knowledgeable folks and guys with experience please chime in.

Cam coming out: 233/241 61X/62X 113 + 4
New cam going in: 224/230 581/590 114 no advance ground in

Currently have 1.7 harland sharp
Ls7 lifters
Comp cam 7.550 pushrods
TFS 215 built heads with dual springs
Stock block

Thanks

mark21742

More than likely you will need slightly shorter pushrods....it takes a few days of down time, but the best thing to do is bolt the cam in, them check to see where the pushrods you have put you...I forget the exact math of how many thousandths of an inch each turn is, but most of the time you will want 1 1/4-1 3/4 turns from 0 lash to torque on your rockers....if you drop the ones you have now in and set them to 0 lash, come back and tell us how many turns it takes to get you to 22ft lbs of torque

99Bluz28

iTrader: (35)

Here you go, open the file.
https://ls1tech.com/forums/14930022-post24.html

schmendog

iTrader: (10)

Good information on there for sure. Sounds like a pretty solid method.

PREDATOR-Z

Yeah double check but those XeR lobes have a small base circle and yours should be in the right range.

schmendog

iTrader: (10)

Ill have to call comp to find the difference of base circle diamater between the two cams, not sure if my current cam has the XER lobes or not.

schmendog

iTrader: (10)

Comp said the base circle of my cam is "One inch four sixty" not sure what measurement that is exactly. Would using a cam doctor be as good as degreeing a cam? A local shop can put in on their cam Dr to verify the specs, if the specs are acurate, would this be just as good as degreeing the cam and just advance or retard as required?

quik95lt1

iTrader: (7)

use and adjustable pushrod and measure the preload desired......best way....every cam is ground a hair different regardless of what its advertised as.......measuring is the best way.....as for the springs just remember whatever full boost pressure you will be running will counteract the springs seat pressure