ok so the cam went flat in dads 48 its a sbc i guess my question is where do i get a new one and what brands are recomended.. right now it has a hydraulic 500 lift 204 duration comp cam.. the car has a 700r4 with 3.73 gears and a 3000 stall should i go back with this combo or whats your guys recomendations? sorry if i sound like a idiot but if it isnt auto body and paint i have no clue about this stuff i can put them together make them run and thats about my extent... i called summit and they have a 501 244 he said this is as close as they have to what i have now.. is this ok or?? i dunno ill stop babbeling!
The xe284h is what u have I think. http://www.compcams.com/Technical/DynoSheets/XE284H-10_001.asp There are similar, break it in by the book.
Best place for a cam is in the engine 'nuuck nuuck 204 duration is pretty tame and no where near that xe284 Is is possible that 204 is a typo
lol i know the best place is in the engine!!! im just goin off what the paper the dude gave us 12 years ago when they built it for us! it might be a typo i dunno? just want a good sound and some performance not like it goes to the racetrack it has skinny bias ply tires not like it would ever put any power down anyway! its got like 6" glass placks and lake pipes so its noisy anyway 70mph almost puts ya to sleep!
Take the numbers off the end of the cam call summit and tell them the nubers and that you want to go back with that same cam unless Pop didn't like the way it ran before it flattened the cam.
the cam that was in there was fine... im not sure why it went flat maybe the rockers was not set right after we switched from roller tip to the full roller rockers? we did have a roler tip rocker break one time but i cant remember what one it was... but i will pull it and check the numbers on it.. so would summit be everyones recomendation on where to buy? all the local parts stores are out of handon anything aftermarket and they dont know a damn thing unless the computer tells them... it also used to foul that number one plug alot...
im never lucky.... the motor never smoked always had plenty of power just started to backfire out of the driver side exhaust.. so i took out the #1 plug got it on tdc and the both #1 rocker arms were loose the others were tight loose tight loose and so on... so this is why im thinking flat cam? am i wrong could it be something else?
At TDC both valves are supposed to be closed, the lifters on the heel of the cam. That would mean there is less pressure on the rockers/pushrods etc. at that point anyway. So, I don't know if that is conclusive evidence of a flat(tened) lobe on that cylinder. A more certain way would be to turn the engine over by hand and pay attention to the range of movement of each pushrod/rocker and see if any are noticably less than any other. Ray
Could just be an adjustment issue. Press in studs coming up. Or significant lifter wear . cam wear on the high lobes can also wear the lifters too, then when the lifters are on the low side they are now short = loose rocker from previous adjustment .
Boy! You sure opened a can of worms! First of all, flat cam lobes come from a variety of sources, and probably the first one to consider is the kind oil you were using. Not all oils have additives friendly to older engines. In the quest for 'a cleaner environment' oil companies stopped putting a variety of chemicals in the oils they produce and sell to the motoring public. If you haven't researched this, or don't know the difference, I'm sure it's on the HAMB. Start there before you shop for a cam. Also, when a cam wears out, metallic particles migrate throughout the engine in the oil. Check bearings, etc. If they're not scarred, and reduced to toast, I would suggest flushing the engine with diesel and replacing the oil pump, lifters (of course), push rods and timing chain, along with the cam. A lot of people now run Shell Rotella because it has the required additives. Some use synthetic oil. No matter you use make sure it's compatible with your needs. (I know this is not as in depth as it could be, but this is a sore subject with me, having had three cams from major cam grinders go sour, it dawned on me it was not them but something else and by luck I stumbled on an article in Hot Rod magazine that ran down the whole deal with oil being the cause of cam failure.) Knowledge is power. Also make sure you are generous in applying pre-break in lube on the cam lobes and an additive in the oil when you are breaking in a new cam. And, praying won't hurt. This is truly one of those areas where a little help from the Big Kahuna is in order.
the heads do have screw in studs and there is no signs of metallic paricals in the oil it looks fine. could the rocker have backed off maybe? we have always used synthetic oil.
Roller rockers and poly locks ? I've seen it happen when guys tighten the lock with a weak wrist. Put a big magmet on the filter and run it some- Cut the filter open and have a look.
ill throw a speaker magnet on the filter tonight and see what happens. how do i know when its tight enough or adjusted right? (the rocker)
Take it to a mechnic. If you are running hydraulics what you want is zero lash then 1/4 turn. Are you running poly locks for adjuster nuts? You cannot run the stock style nuts and expect it to hold an adjustment. it just is not going to happen with your setup.
There's a few different ways to adjust them but two main styles, not running and running. I always do my preliminary adjustments one cylinder at a time following the firing order while rotating the crank. This gives me the opportunity to see and closely watch things in a new set up. Hydraulic lifters require a per-load and I use feeler gauge to measure how far the pushrods moved the lifter plunger. After the engine is fired and broke in I do an adjustment with the engine running. This requires special oil deflector clips and a valve cover sawed in half , sometimes a mechanics stethoscope too. If this sounds like something you are interested in doing I can provide more info, if not a mechanic might be a better idea.
yeah ill be calling one of my mechanic buddies to do this one... ill stick to slinging body filler, metal flake, and candies!
Let me help you out some. Myself and several other fellows got tired of answering the same questions over and over, so we wrote tutorials. Now all we have to do is link the turorials and life is good. Here's one that addresses flat tappet cam failure.... http://www.crankshaftcoalition.com/wiki/Camshaft_install_tips_and_tricks Here's one that addresses ignition timing at the damper.... http://www.crankshaftcoalition.com/wiki/Determining_top_dead_center Here's one that addresses valve adjustment and ignition timing at the distributor.... http://www.crankshaftcoalition.com/wiki/Valve_adjustment_SBC/BBC I don't come over here often, because most of you guys don't know how to say thank you.
Find the problem and correct it, as others have pointed out, back to the original question, CompCams sells hydraulic cams with surface treatment, case hardening process, don't recall the name. Sould set your mind at ease when you buy a new one, do proper break in, if you have high spring pressure consider using break in springs. Its a pain in the ass but it will keep you from wiping a lobe
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