Help picking out a cam...
02-07-2017 | 02:42 PM
#31
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From: NW Michigan
Currently the lifters don't have a tie bar, and when I got new pushrods they were the ones sold for the "retrofit" set up. Bear with me as I barely know what the f*** I'm doing with V8s. I was hoping to not need new lifters as I know that these fit and work and don't want to contend with the issues everyone else is having.
03-30-2017 | 05:38 PM
#32
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From: SF Bay Area
So after some googling, soul searching, reading tea leaves and what not, it looks like the 731 would be a nice fit without having to reinvent the valve train and should slide in with the existing stuff. It's not a huge step up from the ZZ502 cam, but has a better LSA and breaths a tad bit better where I tend to putt around in the midrange anyways.
Any thoughts on that, and anyone have a 731 laying around?
Any thoughts on that, and anyone have a 731 laying around?
Lol!
03-11-2018 | 10:41 AM
#36
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From: SF Bay Area
Dumb question...
I picked up a 168731 Crane cam which isn’t that much bigger than the ZZ502 cam it’s replacing. Crane recommends their 99896 springs which have installed heights of 150 lbs at 1.900 and 454 lbs at 1.310 and the factory GM ZZ502 springs are rated at 150 lbs of seat pressure and have pretty low hours of use. I know it’s always a good idea to switch them out but is it necessary when they are this close?
I picked up a 168731 Crane cam which isn’t that much bigger than the ZZ502 cam it’s replacing. Crane recommends their 99896 springs which have installed heights of 150 lbs at 1.900 and 454 lbs at 1.310 and the factory GM ZZ502 springs are rated at 150 lbs of seat pressure and have pretty low hours of use. I know it’s always a good idea to switch them out but is it necessary when they are this close?
03-11-2018 | 12:22 PM
#38
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From: SF Bay Area
Great question. This is the info someone posted on the Chevelle forum. I’ll dig a little deeper to verify. I guess they look a little soft and were talking about shimming them up for a similar cam. My rev limit is at 5600
“GM at 140#@1.94" ht, 368# rate,”
“GM at 140#@1.94" ht, 368# rate,”
Last edited by Baja Rooster; 03-11-2018 at 12:43 PM.
03-11-2018 | 04:47 PM
#39
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From: Pa
2 different springs can have the same seat pressure and way different open pressure, which may let the lifter jump over the nose of the cam and bounce a few times on the way closed. Plus the open pressure can be way off if it's checked at 2 different lifts.
03-11-2018 | 06:07 PM
#40
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