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Search found 8146 matches

by CamKing
Wed Jan 19, 2022 11:01 am
Forum: Forum Help / Questions / Tips
Topic: PM problem
Replies: 2
Views: 34

Re: PM problem

I have no idea.
I don't see where that's even an option.
I just PM'd her, and asked her to PM you.
by CamKing
Tue Jan 18, 2022 10:56 am
Forum: Announcements
Topic: Don Terrill's book, "The Horsepower Chain"
Replies: 2
Views: 408

Re: Don Terrill's book, "The Horsepower Chain"

Make sure you order your copy, before they're all gone.
by CamKing
Sat Jan 15, 2022 1:57 pm
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

hoffman900 wrote: Sat Jan 15, 2022 12:31 pm I forgot you had mentioned the rollers are really just LARGE diameter flat tappets design wise.
Other way around.
From the design standpoint
A flat tappet profile is just a roller profile with a 56" radius roller.
by CamKing
Sat Jan 15, 2022 12:17 pm
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

Thanks Mike. As a follow up to this post I have another question. The last few years, I’ve had stuff come through the shop that in m opinion had ports with too much cross section. It’s easy to do today, especially since everyone buys heads base on flow. The question is I think the same thing can be...
by CamKing
Sat Jan 15, 2022 11:59 am
Forum: Engine Tech
Topic: Cam overlap degrees for marine cam selection
Replies: 15
Views: 771

Re: Cam overlap degrees for marine cam selection

You need to look at overlap at the seat duration, not the .050" duration.
If you look at seat duration, the Comp cam actually has a lot less overlap.
by CamKing
Sat Jan 15, 2022 10:35 am
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

Mike, Hadn’t thought about them as IR designs, but I can see that now. Thoughts on that type of valve lift curve shape for flat tappet / OHC bucket type systems? All my cam designs(roller, flat tappet, bucket follower, finger follower) are designed the same way. If you took any of my non-roller pro...
by CamKing
Fri Jan 14, 2022 5:44 pm
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

I've only looked at pictures of the 209 Ilmor valvetrain. it was defiantly a compromise to keep the engine the same size as the 4 valve Ilmor. It's funny what lengths Comp will go to, to not call their "Low Shock" designs, what they really are. They're just mild I.R. lobe designs that can be ground ...
by CamKing
Fri Jan 14, 2022 4:50 pm
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

Yikes! I guess with the Buick, if you made an aluminum block it wouldn’t be production anymore, Actually, there was nothing in the rules about the block material having to be stock. When my dad build the 209ci turbo Chevy V8's for indy, in the early 80's, he had Chevy cast the blocks out of Aluminum.
by CamKing
Fri Jan 14, 2022 4:07 pm
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

hoffman900 wrote: Fri Jan 14, 2022 3:07 pm Who was designing Cosworth’s cams back then?
We made cams for Vince Granatelli Racing and Penske, in the late 80's. By mid 90's teams couldn't even look inside the engines.
by CamKing
Fri Jan 14, 2022 2:39 pm
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

No, the 1994 engine when Rahal had to buy a Ilmor-Chevy Penske car to qualify for the Indy 500. You're not going to believe it, but that 1994 engine that Honda developed, used a cast iron block. That added weight made those chassis that were designed around the all aluminum Cosworth, impossible to ...
by CamKing
Fri Jan 14, 2022 1:48 pm
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

Since you were there, what did Honda first mess up with their foray into Indy Cars in the mid 1990s? Are you talking about the Judd-Honda that debuted in 1988 ? That engine was designed and Built by Judd, and Honda just put their name on it. I never looked inside of one, but it was a new engine, tr...
by CamKing
Fri Jan 14, 2022 1:08 pm
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

It's like everything else. There's always diminishing returns. I tell my customers that run Methanol, to run as much compression as they can get, and in practical cases, that's correct, but even that has a limit. No matter how good the fuel is, you will reach a point where the added power made by th...
by CamKing
Fri Jan 14, 2022 12:51 pm
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

That's exactly what we did with the classes that were restricted to 9-9.5:1 compression. there were a lot of restricted compression classes in the late 80's, Modifieds, Asphalt Latemodels, Winston West stock cars, and others. Besides the compression limit, these were engines that had been well devel...
by CamKing
Fri Jan 14, 2022 11:08 am
Forum: Engine Tech
Topic: Cam design basics ?
Replies: 90
Views: 23431

Re: Cam design basics ?

Bringing this one back from the dead. I heard Mark Cronquist of JGR mention today about closing the intake valve "early"* on restrictor engines / limited compression engines to build cylinder pressure, but he has learned with the less rules JGR Baja truck engines that you can close it too early. I ...
by CamKing
Thu Jan 13, 2022 11:35 am
Forum: Engine Tech
Topic: Has a Dependable SBC flat tappet lifter been located ?
Replies: 31
Views: 2957

Re: Has a Dependable SBC flat tappet lifter been located ?

xxdabroxx wrote: Wed Jan 12, 2022 6:16 pm Mike, how aggressive are the lobes you ground on my cam as far as lifter life? R78440-80440
Those profiles were designed for endurance racing, so they're not aggressive.