New Pic of My Truck

[RatPwrd72]

Here's a new pic of my truck at the hit...You guys may remember I was putting a 468 together a couple of months ago. We got it running, but lost a cam on the third pass (it literally wiped out all 16 lobes on the cam). We went on a recommendation from our machine shop (they also build some kick ass motors) and ran a Crower Solid cam this time. After a little tuning, it went 6.72 in the 1/8th with a 1.42 60'......After 6 passes, we went to check valve lash and noticed several exhaust valves loosened up severely. Brought it home and tore into it yesterday to find 4 exhaust lobes wiped out and a couple more headed that direction. So, we're back to square one. Everything is going back to the machine shop to get checked out. It looks like our installed height on the springs is way off. I'm thinking it may be time for a roller.....Here's the pic.

[regan wilson]

I've been there too . When it happened to me a couple times I finally figured out I was sold the wrong inner spring . The inner springs themselves had 110 lbs of pressure . What is your seat pressure and open pressure ? Thats really the only way to find out why this is happening . I dont really think you need a roller there are alot of good solid flat tappet cams out there . If it is like the problem I had the inner springs and a new cam will cost a whole lot less than a roller setup . Bad thing is I'm sure your bearings are toast now they just dont like to have ground up cast iron run through them .

[nxtruck]

I agree with Regan; you may be looking at a seat pressure/open pressure problem. You may also be dealing an oiling or break-in issue.
I will say this, however; if you can afford a roller cam and related parts, then do it. You can stay conservative on the cam grind so that you're not replacing springs every other month, and really the only other thing to keep an eye on would be the lifters. I would say that the best thing you can do to keep the valvetrain alive is to keep an eye on the lash( just like you would with a flat-tappet cam). With the right grind, you should see a difference in power, compared to the flat-tappet. This is assuming that the flat-tappet was right for your combo.
I can definitely understand being on a budget. Believe me, I have more used stuff in my motor than new. I buy my lifters from a friend who races a S/S IA Camaro and he replaces his every 50 or so passes. What I'm trying to say with this is if you can,at all, afford to change over to a roller setup, then, in my opinion, you'd be much better off.
Good luck whichever way you go with it!

[djracer]

I would lean towards a roller also! Chet Herbert cams sells some very reasonable roller stuff! You will have to have new springs but I think it would be worth it in the long run!

[RatPwrd72]

The spring pressures, installed height, and seat pressure all checked out on my heads. So, it looks like the cam simply gave up. I think its time to try a roller for sure. Competition Products and Herbert both look to have some good prices on there stuff...

[nxtruck]

Once you get over the initial expense, you'll be glad you went with a roller setup. You're right; both Herbert and Competition Products have good prices on cams, lifters, springs, etc. I've used Herbert lifters before with good luck, also. I don't know whether or not you have one with your flat-tappet setup, but I would suggest using a stud girdle. They'll help keep the valves in adjustment longer, along with keeping the top-end of the valvetrain more stable.
Good luck with it, and let us know what happens!

[hotrod 80]

I have heard stories of a Lubri-plate compressor oil that is extremly high in Zinc content . This combined with a break in that does NOT include inner springs may be the way you should go . Break the cam and then install the inner springs .

[hiway]

Big solids mean Rotella/Lucas break in oil and no inner springs for sure. A solid roller is the way to go though if you got the budget. Lots of good used stuff out there also. Cool truck!