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Author Topic:   HELP!! got real bad problems with my new motor!!
pbrcowboy2
Dirt Freak

Total posts: 380
posted April 19, 2005 09:49 PM  
i had a 355c.i., with h345np030 pistons that broke my 14103 speedway came in four places!!!

my new motor is a 350 std bore, with h631std flattops with a cc 12-502-5 cam from jr motorsports!!

i used 882 heads with .600 lift springs and stock pushrods with my 355 now with my "new " 350 I am using same heads and valves and springs but my poly locks keep backin them selves off and i have a clucking sound thru the carb im holdin 65 lbs oil pressure but motor seems really really dead!!

thought i might try longer pushrods!! i got a elgin part number pr385s isnt this a standard pushrod tho!! i mean a couple minute of running and these rocker arms r so loose i can dang near put the tip of my pinky between valve and rocker arm!!

im all completly lost and really frustrated, any ideas thanks guys

crc1124
Dirt Maniac

Total posts: 143
posted April 19, 2005 10:24 PM  
I'm just guessing but are your springs too stiff? From what I've have learned on here is that everything needs to match, especially in the valve train department. Usually springs that stiff are used on roller cams. Are those screw in studs or pressed?

Kromulous
Dirt Forum Champ
Total posts: 796
posted April 20, 2005 07:00 AM  
How much lift is on that cam, and is it a flat tapper?

As well, are the studs screw in? or pressed? If there pressed in, get them out. That or pin them in, screw ins would be alot better.

Pushrod length can be an issue, look on Comp cams site, there should be a tech article about selecting the proper length pushrods. Basicly when the lifter is on the backside of the cam (no lift) the roller tip should be on the outter side of the stem, not out on the edge, just not centered on the stem. At full lift, it should be on the opposite side, not out on the edge, but not centered as well. Read that tech article, and check it.

ss99
Dirt Maniac

Total posts: 120
posted April 20, 2005 07:20 AM  
I agree with the other posts - studs may be pulling out. If not, the cam may be going flat on you. I hope not.


leapinlizard
Dirt Freak

Total posts: 402
posted April 20, 2005 07:58 AM  
Try adjusting the poly locks finger tight at the lash you want then back them off a 1/8 turn. Tighten the allen locks and retighten the poly locks 1/8 turn. This should keep them tight. If it doesn't, make sure there is a flat spot on your rocker stud tips. Sometimes this area isn't flat and the poly locks have nothing the lock on to.

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