I think I have found the culprit of my 3000 RPM and higher miss and or back fire. It a worn cam. The exhaust lobe for cylinder 3 is worn down really bad. Basicly the entire lobe is the base circle. Here are some pics.
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Worn Cam
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Re: Worn Cam
wow those pics are very small ummm go here to see larger pics
http://picasaweb.google.com/bcbarlow7737/WornCam#
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Re: Worn Cam
Welcome to the world of flat tappet cams... I guess that could be another reason to call them "FLAT" tappet..
I would STRONGLY suggest you take it completely apart, fresh hone on the cylinders w/ new rings, bearings and whatnot... When a lobe goes away like that it throws all that mess into the cylinder that is most closely aligned with it.. Sorry to hear of your problem..
Take a breath and save some coin and go to a hyd. roller, you will NOT be disappointed that you did. We did a BB Chevy a couple years ago, it had a history of killing a camshaft or two, as BB will, I suggested when we rebuilt it and stroked it to a 489 that we go hyd. roller, the customer decided to get cheap at that point, wasn't long before it killed another flat tappet and had to come completely apart and be freshened, he THEN decided that it was time to switch to a roller, we did and he said it like night and day as far as power, we didn't dyno it the first time, but we did after the roller, so unfortunitly we don't have numbers to compare to..
Someone on another forum always saw me ragging on flat tappet cams, he had just invested a bunch of money in a stroker, 6 pack SB Mopar, he had used a flat tappet, with all the talk he heard from me he got scared, he pulled it down and switched to a roller, both combos had been dyno'd, I believe it picked up like 40/60HP, can't remember exactly, but he was VERY excited. He also said the sound and response was night and day!!
Do it NOW, or be sorry later..
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Re: Worn Cam
X2. I've had some bad experience with flat tappets lately, solid and hydraulic. The best lifters and racing oil or good diesel oil will live with a very mild cam, but with any kind of lift or spring pressure the cam will die.
Do a roller.The official Bangshift garage door guru. Just about anything can be built using garage door parts, trust me.
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Re: Worn Cam
10-4. Both of my cars have little hydraulic flat-tappets, and with diesel oil and crossed fingers I haven't wiped any out for almost three years, now. However, my buddy's aggressive solid cam got wiped out like three times. He switched to a roller and hasn't had any problems, and picked up 25 hp.
Next motor I build will have a roller, no questions.The official Bangshift garage door guru. Just about anything can be built using garage door parts, trust me.
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Re: Worn Cam
Originally posted by HoosierGTASorry that your cam went flat but, aleast You have an excuse for a bigger can! What size you going with?
Ask him if he wants my cam specs.....should wake it up nicely... ;D
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Re: Worn Cam
unfortunately the block i have is a 2 piece rear main flat tappet 72 truck block. Retrofit roller cams are really expensive and I don't have the money right now to go crazy on this thing. I'm on vacation till Thursday. I've got everything torn apart waiting for the new cam to get here from summit Monday morning and then I'm gonna throw it together and hopefully Tuesday or Wednesday haul it out to hoosiers house so we can break the cam in with out ticking the neighbors of with the camaro singing through the flowmaster. But thanks for the advice and if you have anymore that you can offer considering the boat I'm in it would be greatly appreciated
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Re: Worn Cam
Originally posted by VortecRSunfortunately the block i have is a 2 piece rear main flat tappet 72 truck block. Retrofit roller cams are really expensive and I don't have the money right now to go crazy on this thing. I'm on vacation till Thursday. I've got everything torn apart waiting for the new cam to get here from summit Monday morning and then I'm gonna throw it together and hopefully Tuesday or Wednesday haul it out to hoosiers house so we can break the cam in with out ticking the neighbors of with the camaro singing through the flowmaster. But thanks for the advice and if you have anymore that you can offer considering the boat I'm in it would be greatly appreciated
You have rejected my reality and substituted your own..
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