So upgraded my cam on my iroc sbc 305 to a crowler hydralic roller cam which has a max lift of 484.Can I reuse the lifters which are in good shape and reuse the factory pushrods and valve springs.

Cheers.

 

There are calculations you need to do off the Cam card. You need to know what your current valve train can handle before you hit coil bind. You may also need to change your pushrods as well once you figure out your rocker tip sweep across the valve tip.

 

hmmm no sweep as I have stamped rockers, yes I did the calculations and valve height should be good at 7.5 install height safely..However not sure of pushrods.

 

Never heard of "Crowler". However I do know of Crower, started back in the 60s by Bruce Crower. Is that who your cam came from? I'm guessing their 00480 or 00481, or perhaps 00461 or 00463?

Lifters, yes generally you can re-use if they're in good shape.

Push rods, iffy at best. Stock pushrods are made from about the cheeeeepest thing that's shinier than rubber. They might "work" butt will be one of those things that might just flake at any moment.

Valve springs, ABSOLUTELY POSITIVELY UNEQUIVOCALLY UNDER ANY CIRCUMSTANCES WHATSOEVER DO NOT RE-USE. I can't think of anything stuuuuupider or more destructive that you can possibly do to an engine than that. Stock ones aren't even able to control valve motion on a STOCK cam, let alone ANYTHING aftermarket, and ESPECIALLY not something aggressive and "performance" oriented.

In 2026, the best choice for springs, is probably "LS6" ones such as from Texas Speed, and the Comp 787 "adapter" retainers with their associated hardware, set up to 1.800" installed height, without the stock "rotator" garbage on the exhausts. That setup will work fine with any of those cams. I also strongly suggest putting in new valve guide seals; use the FelPro "positive" ones that they list for intake, on both int & exh; NOT "umbrella" type, and don't even bother with the useless O-rings that go inside the retainer after you put it on the valve with the spring compressed and before the retaiers.

 

Say i just happen to have some ls6 springs install height is supposed to be 1.800 however calculations say I'm safe at 1.750 can I set them to that because last experience with these was I found some measures Shor and I don't want to remove material from the seat and a .050 offset keepers leave not much valve head for rollers to sit on.

 

Not sure about "calculations". Kinda depends on the numbers that go into them, more so than the numbers that come out. GIGO as they say.

That said, LS6 springs are good to about .550" lift in LS applications. Of course the springs don't open their eyes and look around and identify the castings they're installed on and decide accordingly how they're gonna behave; butt that gives you a rough benchmark. If they'll tolerate .550" lift at 1.80" IH, then they should be OK with .500" lift at 1.75" IH. So more than likely, it wouldn't be a problem.

OTOH the exhaust "rotators" are about .120" tall; meaning, you take em out and throw em in the trash where they belong, you automatically pick up that much extra IH on the exh side. Similarly, the oil splash shields go in the trash; and those are another .025" or so that you'll gain. Also keep in mind, you almost can't have "too much" seat pressure; valve float IS NOT the valve getting tossed into space at the peak of the lobe, what it REALLY is, is BOUNCING OFF THE SEAT when they should be closing, which makes all the parts crash into each other. THAT'S why crappy valve springs are so destructive: it's like taking a hammer to every part in the system, thousands of times a minute. Valve motion control is most critical near the seat. Lower IH on any given springs, as long as they don't bind, will help that. Measure measure measure measure measure. If you want 1.800" IH, it's almost always available without any further machine work to the heads.

.050" offset keepers, should they be required, won't cause problems with rockers.

You'll need to buy a shim assortment no matter what to set ANY springs to ANY known measured controlled IH, unlike the factory who just jammed abuncha crap together and whatever it was, it was. Stock machine work is NOTORIOUSLY inconsistent. So use your spring micrometer and do the best you can.

I notice you didn't ask about re-using your stock rockers. I would NOT do that. Mostly because I've watched stock rockers bend and flap like a flag in the breeze, with a Strobotac. They're scary. Stock rockers might as well be stamped from sheet RUBBER for as floppy as they are. I'd STRONGLY recommend upgrading them, preferably to steel ones, and NOT cheeeeeeeeep chinesium ones off ebay or the like. Crower and Comp are the 2 go-to sources for those.

 

I have self alignment roller.rockers from summit for another project im sure they would work