Thread: 383 Stroker- cam clearance

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I bought a comp xr270HR-10 roller cam that s too big for the rods to clear. Unfortunately I don't know the make of the rods I have-reusing a 383 rotating assembly from a rebuilt engine, which worked fine with a flat tappet cam in an old 2-piece block. Was this simply a rookie mistake that can be fixed by ordering a small base circle cam, or do I have to do some measuring? If the later, how do I do that?

Thanks,
Ken

Originally Posted by kfox

I bought a comp xr270HR-10 roller cam that s too big for the rods to clear. Unfortunately I don't know the make of the rods I have-reusing a 383 rotating assembly from a rebuilt engine, which worked fine with a flat tappet cam in an old 2-piece block. Was this simply a rookie mistake that can be fixed by ordering a small base circle cam, or do I have to do some measuring? If the later, how do I do that?

Thanks,
Ken

scat makes a rod that takes a cap screw and the under of the head of the cap screw is i think about 1.400 were many are a long 1.600 bolt and with the cap screw there on need for side nipping the head of the threw bolt. that needs to be done with a stock rods. the scat stroker cap screw rod #scr5a7 for 5.7 or #sc6a7 for 6.000 are much shorter were the cam can hit. the hyd roller lifters have a 700 wheel diameter . i would be never carfull going to small base cam . i built 383 with much bigger roller cams then with you are using with the scat cap screw rods with no work needed or the comp star rods will give you more room as well or just use another cam

If the cam is new you can contact Comp Cams and tell them you need to exchange it for a small base circle cam and they will send you another with a return shipping label so long as the cam has not been used. I explained to them that I had installed it and the rods would not clear the cam and they told me "No Problem". Very good customer service. Another time in a state if incoherentness, I had a bit of a problem with clearance and mistakenly aligned the wrong set of timing marks.

Thanks Ed. That's great to hear. While I'd prefer to get some rods that fit, I don't want to have to get everything rebalanced.

Originally Posted by kfox

Thanks Ed. That's great to hear. While I'd prefer to get some rods that fit, I don't want to have to get everything rebalanced.

your not out of the woods yet. if rods are threw bolt and no one did the prep work your not going with much cam. if you go smaller base circle 900 . lifter body could hit the ramps . better check see if your lifters are going to work with small base

That's the story of my life these days... Rods have been ground around the shoulders. The assembly worked in a similar setup with a 214/214 flat tappet cam. Thanks for the input.

Maybe you should re check the timing gears/chain for correct timing----and then if correct, there will probably be only 2 that hit and might only take a small amount of extra clearance----

Talking about rebalancing----with extra clearance work, the rods you have will be out of balance---------