Re: Serious Cams
After seeing the picture of the Chevy 400 with the conversion, I bought a spider and dog-bones for the Chevy V8 roller. When finances permit, I'll be buying the V6 roller lifters for both a Rover V8 and the Chevy V8.
Regarding splicing the spider, I expect that it's spring steel. I have tried to weld metal like that before and it's not simple. I'd guess that gluing and screwing are what's going to happen. I'm a little confused. Have people done roller cam conversions on BOPR V8's before? Using the V6 lifters? |
mgb260 Jim Nichols Sequim,WA (2463 posts) Registered: 02/29/2008 08:29PM Main British Car: 1973 MGB roadster 260 Ford V8 |
Re: Serious Cams
There was one guy talking about doing a Buick 350,lots of Buick V6 and Chevy V8 conversions.As for the spiders, I would just bolt both halves down and overlap.
Edited 1 time(s). Last edit at 12/14/2009 06:57PM by mgb260. |
roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Serious Cams
Paul, I think this forum is it. Previous conversions were mega $'s , skirted mech. rollers. Race car , only stuff. roverman.
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Re: Serious Cams
Art, I guess I'm a little compulsive and impulsive. So far, I've purchased 20 roller lifters. 12 left to go. I have the Chevy spider and dog-bones. Now I'm searching for the Buick V6 spiders and some more dog-bones.
12 new lifters for $77. It's a better price than the normal Chevy roller lifters, but it's going to add up. |
mgb260 Jim Nichols Sequim,WA (2463 posts) Registered: 02/29/2008 08:29PM Main British Car: 1973 MGB roadster 260 Ford V8 |
Re: Serious Cams
Paul you might be the first to get it done with the Rover! Are you planning to beef up the springs and circlip in the lifters too?
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roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Serious Cams
Paul, do you think? Got Cam? I will need word from Herbert this week or move-on.I would like one cam with bolt pattern for sbc. and bolt Buick distributor gear on top, using wet belt, sbc cam drive with(dynamic cam timing). I believe hyd. rollers will really shine, in most of the builds, for our little friend. roverman.
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Re: Serious Cams
Jim, until you asked, I hadn't even thought about it. My applications will be relatively mild, but I should probably consider the interplay between the valve springs and the lifter springs. The upper end of the planned operating speed was 5500 rpms.
At this point I was only thinking in terms of beehive springs. If titanium retainers are cheap enough, I'll use those. Stock rockers. Pushrods will have to be custom, but I'm not going to gold plate them. Because the circlips are cheap enough, I'll probably go with that. Art, the cam will have to be a custom/prototype job. I suppose if this works, the cam grinder can use the information to provide a retrofit option for Buick small blocks - 215/300/340 and Rovers. So maybe we can cajole Comp or Herbert into selling for a reasonable price in exchange for the information about how to do it. |
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NixVegaGT Nicolas Wiederhold Minneapolis, MN (659 posts) Registered: 10/16/2007 05:30AM Main British Car: '73 Vega GT 4.9L Rover/Buick Stroker |
Re: Serious Cams
Art, I know you were considering VVT in the past. I think I'm on to what you're saying with the dynamic timing. Are you thinking of putting a servo on the tensioner? I suppose you could use the fuel pump port on the front cover for something like that. Have it change timing based on RPM or demand?
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roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Serious Cams
Nic, and clan, mentally I'm invisioning an adjustable spring-on-tensioner,(lead/right side), upon which,oil pressure/cylinder assem. would oppose to, "retard" cam as rpm/oil pressure increases. Real basic, might work. There are many ways to make it more complicated. I like simple. This brings up a complication. In this set-up, I think I want crank driven ignition timing,rather than following the cam all over. We'll see. roverman.
Edited 1 time(s). Last edit at 12/15/2009 01:59PM by roverman. |
Re: Serious Cams
I had always thought that flywheel timing would have to be much more accurate than distributor or damper timing. The pick-up would make a heck of a hall-effect signal at the speeds it goes at its periphery.
Re; VVT, how's about a Rhodes-type lifter, maybe tweak it with cold (viscous) oil feeds to the lifters upon demand. A two-stage lifter that has its basic pump-up but then pumps up more when colder oil is supplied via a oil cooler/bypass system. You'd have to be rather picky about the oil you use. I'm thinking something like Mobil1 15w-50 could have its viscosity altered enough at operating temperatures to do the job. |
roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Serious Cams
Paul, Good Luck with that. The main complaint with, "Rhoades"/Hi leak-down lifters is no (2) are exactly alike in how much they pump-up. Reports on fairly serious bbc's is "never". Off course they reduce duration by reducing lift,(TICK), not a good thing for "flow under the curve". I've used them and now consider them a, "noisy band aid". Item #1, I believe Rover, crank trigger uses the flywheel. roverman.
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Re: Serious Cams
Jim, Could you tell me the URL for the Buick web ring with the roller conversion information?
Thanks. Wait. I found it. [www.v8buick.com] [www.turbobuick.com] Edited 2 time(s). Last edit at 12/15/2009 09:14PM by pcmenten. |
BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6469 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Serious Cams
I agree with Art on the Rhodes lifters. I thought I needed them to extend the rpm range but the lifter tap drove me nuts. At least if it had been all of them it would have sounded like a loose solid lifter cam, but no...
Jim |
NixVegaGT Nicolas Wiederhold Minneapolis, MN (659 posts) Registered: 10/16/2007 05:30AM Main British Car: '73 Vega GT 4.9L Rover/Buick Stroker |
Re: Serious Cams
Post from Jim in the Big bore thread. It's a good one...
Quote: What do you think? Cut it before heat treating... Has anybody done this before? Seems like a good way to reduce weight and increase bend strength. I was thinking there is less shear force then bend force. It works on the rocker shafts... |
roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Serious Cams
Nic,Jim and clan, I'm magnetically opposed to cast iron. It's best left for those 300-350 sbb folks. Getting over zealious with large bores and "tractor strokes"-Nic, only leads to problems like, bad cracks-internally. I shall shun Detroit wonder metal in favor of a lighter path to Nirvana- Ravhi Shankhar-Rover.
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roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Serious Cams
Volume changes everything. Looks like at 50 cams in a run could get the cost to approx. $250 ea.? Latest up-date on potential LCA's would be approx .106-112deg. Probably adequate spread ,especially with dynamic cam timing. Which snout, early/late? I like late for varicam potential. Consensus time, roverman.
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roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Serious Cams
As I recall, The early style flange can be machined to fit Rover retainer plate. "Early" not possible for sbc belt drive.roverman.
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Re: Serious Cams
I would be using one to replace the cam in a 4.0 cross-bolted engine. I assume that's a 'late' style. But I would also be thinking of replacing a cam in an Olds 215.
Jeepers, Art, $12,500? No promises, but I might be able to help a little with that but not that much. I'll PM you. |