CAJUN C4

do you think 165#'s is too much valve spring seat pressure for a ZZ4 Roller Cam used with L98 Heads?

jburnett

165lb seat pressure??? Yeah, that's too much for that cam. I would say 115-120 would be preferable; now if you had a bigger one with over 230 degrees of duration 165's would probably be okay. I ran 170 at 1.95" installed height with my hyd. roller I used to run (242/248 at .050")
-Jeb
PS- Stock is only about 90 which is way too little...

1MoorTym

Way too much.

Just a suggestion, why don't you use the springs for the cam and the heads that you're suppose to.

That would be GM 12551483 with 101# seat pressure. They're available in as a kit under p/n 12495494.

Just look at your signature and saw you have an 84. Don't think the spring diameter is good for iron heads. p/n 10185086 may work its got a 1.273" diameter and also spec'd for the ZZ4 cam.


[Modified by 1MoorTym, 6:35 PM 5/8/2003]

CAJUN C4

I'm building an L98 with 133 Heads & ZZ4 Cam Havea a chance to buy some TPIS ZZ9 Springs for a song & that would be the seat pressure if I used them. I'm gonna buy the GM ZZ4 Springs as you mentioned.Just didn't know if that 165#'s or so was too high
Thanx for all your help.

89vette

Its way too high as others have said. Also I would not buy used valve springs unless they were tested and verified. Use the spring that GM recommends or call Comp and/or Crane and ask them.

richy rich

for what it's worth I run the zz-4 cam in my stock 94 vette[great cam even w stock pcm & auto]I run the LT-4 chepie springs[105lbs]The zz-4 crate comes w these LT-4 springs;so I figured they would do the job for me as well.

Nathan Plemons

I run 150 or more. The springs I have are 150 at 1.8" installed height, I just don't remember what we installed them at.


[Modified by Nathan Plemons, 8:13 AM 5/10/2003]

65Z01

If you use the TPIS #700-132 springs (for use with ZZ-9 cam) you can install them at 1.85"-1.80" for 105-125lbs seat pressure.

TPIS recommends 110lbs seat pressure with their cams for up to 6,250 RPM; slightly higher seat pressure if you use 1.6:1 RRs.

Remember that more spring pressure than is necessary to follow the cam profile throughout the RPM range only contributes to early cam and valve train wear.

It would be better to use the lower spring pressure and upgrade to Ti retainers with 10deg locks.