Roller lifter question
#1
VIP Member
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Roller lifter question
I have 2 Gen 6 502 roller motors with 70 hours on them. I am changing camshafts. Can I re-use the roller lifters or do I need to buy new ones. The old cam was stock at .483 lift and the new cam is going to be between .587 and .610. Again both cams are roller cams.
Thanks,
Dave
Thanks,
Dave
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Last edited by Bigwavz; 03-21-2005 at 01:10 PM.
#3
MarineKinetics
Platinum Member
Re: Roller lifter question
Dave,
The factory guide bar lifters are limited to .326" lobe lift, or approx .555" valve. If you choose a cam that specs higher you must replace the lifters.
Bob
The factory guide bar lifters are limited to .326" lobe lift, or approx .555" valve. If you choose a cam that specs higher you must replace the lifters.
Bob
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Re: Roller lifter question
I have the exact same issue to deal with. One of the last things I have to sort out besides measuring for new pushrods. So question is. What are the best lifters to use?
#6
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Re: Roller lifter question
I know your not supposed to use stock lifters beyond .326, but I have personally used as much as .378 lobe lift with factory lifters, that's .642 valve lift with 1.7 rockers. I think it just depends on the cam. I think I discovered this on accident because I had bought the cams and lifters for a brand new set of short blocks and I decided to just see if the factory lifters would work. This particular cam looked fine with factory lifters so I used them. These motors have never had any problems.
The main issue is to install the cam and check for interference with the guide bars. You have to check every lobe for interference. Check to see if it is too far down in the guide and make sure it doesn't come up too far. You can buy new factory lifters a lot cheaper than aftermarket.
I think .326 is a good guide to make sure you check anything over this much lift.
Like I said YOU HAVE TO CHECK THIS.
Just remember wrong or weak valve springs will make the BEST lifters fail.
The main issue is to install the cam and check for interference with the guide bars. You have to check every lobe for interference. Check to see if it is too far down in the guide and make sure it doesn't come up too far. You can buy new factory lifters a lot cheaper than aftermarket.
I think .326 is a good guide to make sure you check anything over this much lift.
Like I said YOU HAVE TO CHECK THIS.
Just remember wrong or weak valve springs will make the BEST lifters fail.
#7
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Re: Roller lifter question
I would use new lifters. Crower has a new design that oils the rollers. I will be going to roller cam with these lifters from flat tappet solids next rebuild.