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Author Topic:   Done for the year
ryan
Member
posted July 30, 2002 02:20 AM
I am quitting for this year and probally next year. I am going to race a cruiser for a year and give my wallet a break. But I still want to know what went wrong!!
Went through my third cam in 14 races and I don't know why. I ran the same block last year with no troubles. The only thing different I did this year was have the crank ground and different heads (441 last year 462's now). Two of the cams were midwest the other was a speedway. I have checked for coil bind and I have plenty of clearance there. I am wondering if I am doing something wrong or is it something in the block or heads. Last year was our first year in a street stock. We had no experience with solid cams whatsoever. We thought we had a hyd. cam so we set the lash accordingly before we started it and it had no compression we messed around for a while to figure it out and we did a bunch of cranking. We figured it out and got it started and we didn't really break in the cam and we didn't have a lick of motor trouble all year. This year we broke in all of the cams in like you are supposed to and have been having fits with it all year. It's frustrating not knowing whats going on. Here is our current setup 355 sbc 462 heads. Cams have been in the low .500 lift with 106 centerline, 7 quart pan, hv pump, racing 20-50 changed every 3 nights, acdelco filter, no restrictors any where, stock block except for the bore, 5.7 stock rods, regound crank ten and ten, no oil temp gauges, oil pressure ususally around 60-70 at idle cold 50 after the race(too much??) If you need more info just holler.
p.s. the bad lobes arent all in the same holes. Last time it dished out two lifters the time before the cam had lobes worn down. This time I haven't torn it down yet so I don't know


ryan
Member
posted July 30, 2002 02:24 AM
Just thought I would add that I have 1.5 long slot rockers with hardend push rods.Also I am not giving up racing for the year for just the cams I have had a ton of problems this year and Its to hard and expensive to work 40hrs a week at work and 40 hours a week or more on the car and still find time for the wife


dirtbuster
Member
posted July 30, 2002 09:13 AM
are you usding new lifters with ea cam?

Did you ever chack to see if you pushrods were spinning when the motor was running?

When you tore these motors apart did any of the bad lifters stick in the bores and you had to drive them out? Or have trouble getting the new ones to slip into the bores?

ryan
Member
posted July 30, 2002 12:11 PM
Yes new lifters each time.
I never checked to see if the push rods were spinning didn't even think of that. How fast should they move?
I had two lifters I had to use pliars to get free. We never had any trouble puttin the lifters in. Thanks again.

[This message has been edited by ryan (edited July 30, 2002).]

dirtbuster
Member
posted July 30, 2002 01:35 PM
If you pushed or pulled with pliers the worn lifters back through the top of the motor you may have put a small burr on the bottom of the lifter bore.. the lifters will sometimes wear a little at the cam then they wont fit back up through the bore. I just went through this last saturday had to take the cam out then push lifters down through to the bottom of the block. If you dont do this the bottom of the worn lifter will catch on the lifter bore and then put a burr on the edge of the lifter bore. Then when yuo put the new lifter in it will catch on this burr and will stick and the burr will keep the lifter from rotating, and thus wearing out the cam lobe or lifter face. This is why i asked if the pushrods were spinning. When you take it apart you can run your finger down ea lifter bore and feel whether or not there is a burr.. Be carfeul as the machined edges are sharp and will cut you. If you find one you can hone it with either a lifter bore hone or have you r machine shop doo it. Just be careful no to remove too much material in the bore itself. I had to do this in a block that had been sitting for several years to get the bores cleaned up from surface rust. I didn't want anything to stop thelifters from rotating.

Just a thought. May explain why it is the same block as last year but you are having trouble this year with cams.

Monster
Member
posted July 30, 2002 09:30 PM
What about valve springs? Are they different on the new heads? Stronger? Are you tearing the block completely down after these failures and scrubbing it with hot soapy water to remove all traces of those ground-to-abrasive-powder lobes and lifters? Dirtbuster touched on the burr deal, and also mentioned that those "machined edges are sharp and will cut you." We soften that edge! It will also scrape away oil, just as pretty as you please. We also Deburr all of the lifters in the oil band area(Not the face!). We use a Scotchbrite wheel on a bench grinder. Use some kind of thrust button to make sure your cam is not jumping back and forth. Look at your pistons VERY closely for signs of valve contact. With your cams, it won't be on the valve face area, but possibly down in the edges of the valve notches. Even the pros quit when it's no longer fun.


ryan
Member
posted July 31, 2002 12:15 AM
Lifter Bores were honed after this last cam went out and they spun freely. The valve springs are the same type as last year but they are new. After the first cam no we didn't tear it down after the second cam we did and we cleaned it up and re ringed it.
Monster I am not quitting I am just moving down a class for a year or so. I will still have the street stock around. Its hard to enjoy the sport when my car hasnt run right but 2 or 3 times this year. It wasnt always the motor but something would always break or get wrecked or something would get s.crewed up. This weekend I lost a cam and busted the top mounts of my rearend in two laps of racing. It's depressing that a guy I can always pass on the track no matter whats wrong with my car is only two spots behind me in points. Granted we have 40 plus s.stocks and 95% of them are top notch. thanks for the help so far guys.


Gene
Member
posted August 01, 2002 09:45 PM
Sounds like way too much seat pressure. Were the cams "kit cams"? You need to use the proper springs with the cam.


ryan
Member
posted August 02, 2002 12:02 AM
The first two cams were sets the last one wasn't. The last two cams had similar numbers 504 vs 507 all the other numbers were very close to each other. I really don't know what the H#ll is going on in there.


ryan
Member
posted August 05, 2002 12:01 PM
What tool do I need to check seat pressure. What are acceptable ranges. If its too high how do I lower it??


dirtracer14
Member
posted August 05, 2002 04:58 PM
To check seat pressure you have to measure how tall the spring is in the head ,then put it in a spring rate checker to see what seat presure is. I think he is mainly talking about seat pressure for breaking in the cam at first, most cam people have told me that once the cam is broke in corectly it should be fine as long as your not way over the recomeded pressure. To use the springs if they are to stiff i think they sell a retainer that will take 50 thous out of the height to lessen pressure or if you have room i have heard on the aftermarket heads they take the spring pocket down a tad. Im not an engine guy but have had alot of problems with wearing lobes out on the cam in the past,and it gets vary frustrating!


6pack
Member
posted August 06, 2002 10:52 PM
6 pack- no they haven't been tapped. I am going try a different block this time around. It kinda ****'es me off a bit that I guy I know that runs the exact same setup, but has restrictors to keep the oil off the cam and he doesn't break them in and has no problems. Cant say **** either

[This message has been edited by ryan (edited August 07, 2002).]

[This message has been edited by jammin (edited August 08, 2002).]

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