Thought I was swapping out a set of stock cams on my 10 ultra for a set of new Andrews 48, bearings, lifters etc. Open it up to find adjustable pushrods, Torrington bearings and cvo 255 cams. Dealer never told me and since my header install in 2016 I’ve been running a power vision tune based on stock with high flow a/c and S&s headers.
my question is should I still swap out the bearings and is there any need to change the adjustment on the push rods or can I just reinstall.
thanks

 

If it were me, I would be tossing the 255 cams, replacing the inner cam bearings, installing the 48 cams and readjusting the pushrods. Pretty sure FM can provide a decent base map for the 48s but a proper dyno tune will be necessary to truly dial in the 48 cams. The 48s will pull off idle very much like the 255s but will carry out the curve another 500 rpms or so. There is a market for the 255s; peddle them on Ebay.

 

Thanks, I already have the cams and they will be going in. So I still need to readjust PRs even though they are both bolt in cams? Btw rocker covers are off already so was just going to drop them in. ( had other work to do and obviously thought they were stock pushrods) I don’t want to risk F’ing up adjusting pushrods.

 

I am just guess and I am sure someone with more knowledge will be by, but I would think you will need to adjust them unless the base circle of the cams are the same. Then again I could be wrong but why chance it?

 

If you have the rockers off...why not go with fixed length push rods?

 

IIRC, base circle of the 48 cams is a tad smaller than the stock cam base circle; I don't recall how much. A lot use stock push rods with the 48; some get some noise and some don't depending on factory clearances in how the valve train stacks up. You could probably get away with using the adjustables without readjustment and if you get some valve train noise, go in and increase the length 1-2 flats depending on TPI. Having said that, if it were me, I would readjust and set preload at .135" but I am **** SOB and want to know that the lifters are sufficiently preloaded.

 

i appreciate your input. The PRs are the SE adjustables #18422-08 int. and #18413|08 exh. Instructions say 2.5 turns to put it around .104 ,how many turns to put it at .135? If it makes a difference lifters are feuling hp4000.

 

3 turns 2 flats.....?

 

Those are 24TPI pushrods and 3 turns + 2 flats will set preload at .1386"; which would be fine with me. Just be sure you are adjusting with piston at TDC on compression stroke.

 

I was just going by this chart and 20 flats ended up being about .132