Web Cam #218 shim on top?

Hey guys,

I'm in the middle of a cam upgrade due to a wiped lobe on my 0.365 drop in cam. Not sure why it failed. Will post pics soon.

Is anyone running a Web #218 (0.418 lift 242 deg @0.050) cam with shim on top? Web lists that cam as shim under but I've seen cams from other companies with the same lift listed as shim on top. Thoughts?

From what I recall... Shim under bucket, high compression pistons and performance valve springs.

I run .418 lift with shim on top. Been that way over 12 years.

roy-b-boy-b wrote:

I run .418 lift with shim on top. Been that way over 12 years.

Thanks Roy! Are you running a Web #218 grind?

The reason I ask is because the #218 is a really fast acting cam. Most 0.400+ lift cams have a lot more duration than the #218. I'm concerned that the lobe profile will also be a factor in determining shim on top or under.

It's not a lot quicker than the cam you're replacing.

And, that's not what determines S.O.T vs S.O.B.

118 Grind

Master # Lift @ .020 @ .050 @ .100

118 .365 283° 246° 216°

218 .418 280° 242° 218°
483 .395 266° 242° 216°
493 .415 276° 252° 229°

Subtract Dur at .100 from Dur at .020

118 = 67
218 = 62
483 = 50
493 = 47 [I run these in my bike with S.O.B.

I've run the 483 in a J motor with S.O.T. They're a lot quicker than either of the other two grinds. They don't rock the shim down in the bucket oil groove. That's what you're fighting against....

If I were going to go against Web's S.O.B. advice, at the very least, I'd find some newer J model S.O.T. buckets with the narrower oil groove in the bucket.

See the lobe wipe pattern in the photo. The cam lobe has moved far enough past where the oil groove is in the bucket under the shim. That was with those 483 grind Webs.

A lot of nice cams still available. The one that's over .400 and keeps S.O.T. is the Cam Motion Z4.

Anyway..... do what you like but the info might come in handy

Look a the lobes on a Megacycle 470-15. Your jaw will drop open at how pointy they are. They shocked me. They have to put midrange in the mix with.410 lift as pointy as they are. I setup a head for some but never heard from the guy as to how the cams worked....

All good info Larry. Thanks!

I found the Z4 grind listed here at a good price
store.starracing.com/servlet/Detail?no=700
But it seems to have a little more duration than I want. I'm also considering the K410. Do you have the same lift data (@0.020, @0.050 @0.100) for those two grinds?

Also, the 483 grind you listed looks good but I don't see it in the Web catalog.

davel wrote:

All good info Larry. Thanks!

I found the Z4 grind listed here at a good price
store.starracing.com/servlet/Detail?no=700
But it seems to have a little more duration than I want. I'm also considering the K410. Do you have the same lift data (@0.020, @0.050 @0.100) for those two grinds?

Also, the 483 grind you listed looks good but I don't see it in the Web catalog.

There's an Aussie member on here that I setup with porting, Z12 Grind cams and CRS29's. He wanted midrange pull. His bike is an orange KZ...it's on here somewhere. I think in the "one engine mod" thread. PM him.... he'll give you the straight skinny on the outcome... I really like that Z1 Grind. K410 is also nice and keeps S.O.T. but I think the Z1 gives it more bottom....

No, I don't have the specs you're after. Wish I did though. I have a bunch more Web's though..

larrycavan wrote:

Look a the lobes on a Megacycle 470-15. Your jaw will drop open at how pointy they are. They shocked me. They have to put midrange in the mix with.410 lift as pointy as they are. I setup a head for some but never heard from the guy as to how the cams worked....

This is a good looking cam for what I'm after. Their catalog on the web site is from 2008. I'll make a call on Monday to see if it's still available. This might be the one.

Thanks!