BritishV8 Forum

Art,

IO/IC/lift:15°/67°/0.283
EO/EC/Lift: 65°/21°/0.283
Duration int/exh: 266°/266°

These were based on Ford 5.0 cam specs. I think this has a LSA of 112.

Whoa! I was looking at the picture of the Chevy block with the roller lifters. The glyptal painted valley looked similar to the Chevy engine I have for my 55 Chevy, but I was assuming that it was a 305 or 350 roller block. Then I noticed the steam holes. It's a 400 (which means it's non-roller) like my small block. So, some of the parts are retro-fitted.

I'll have find out more about what parts they used. Looks like a pretty slick installation.

3100 and 3400 FWD and 2.2 four cylinder Chevy,also used in other GM cars for the rollers. The spider and dogbones from 86-88 Buick 3.8 roller FWD engine on older RWD turbo 3.8.The spider and dogbones in the Chevy are factory newer Chevy retro fitted on 400 .

Wide Open Throttle (WOT-TECH V6 Performance) sells the small V6 lifters with LS springs installed for high lift cams and stiff valve springs. Supposed to be twice as stiff as the stock lifter springs.They sell just the heavier springs for $29.95 for 12, I imagine you could get 16 from them.  More stabilty at high RPM,anti-pump up?.

Sounds like a decent price. I'll be investigating beehive/ovate springs too. The higher mass of the roller lifter makes 'heavier' springs necessary, but beehive springs avoid spring harmonics and you can get away with lighter springs. Considering the relatively smaller base circle of the Buick/Rover cam, seems like lighter springs are a good idea to help with cam life.

I wonder if that's why Olds used beehive spring on their 215?

Latest Supercharged Buick V6(Series 3) has Beehive springs. Supposed to be good to .480 lift.

Actually, I think the first "beehive", in real production, (some antique engines used a similar design), for GM, may have been the Olds 394". I believe slightly pre-dated the 215. I have a theory, un-proven, that a 1.6 rocker ratio will return the push rod side of the valve train, easier than a 1.5, all else being equal. IE., harder for same parts to open/easier to close. I find it "entertaining" that Comps Cams was blowing, "orfice smoke rings", by claiming "they" invented the beehive.  Ok, spring on far right is stock MGB valve spring?-explains the "tilt".Not that long ago, I bought my 1st. set of beehives from Comp Cams, $57.They sure got "pricey" since then!  Doug Herbert is still diggin for a quote for roller cams. Rollin On A Riv.....roverman.

Roverman, All those springs are the small springs inside hydraulic roller lifters. The 2 left small and large are V6 the 2 right LS7-mucho stiffer. I was thinking the newer beehives might work on the Rover. On another thread I have a picture of Mopar 318-360 shaft mount rockers that may be modified to work.

British Car Conversions also sell the upgrade LS internal springs for the small V6 roller lifters. A guy on the J body forum also recomends replacing the internal wire clip with a 5/8" internal snap ring. The mods would be good for 7000+ RPM. Are you guys doing the roller lifter swap planning on overlapping two 86-88 Buick V6 spiders. I presently have neither a 215 or Rover,but have over the years had 215's,Buick V6's,Buick 300 and 350 V8's. I am interested in the strokers also because in my opinon the 215 was just too small.

Jim and clan, My 1st. set will be,gutted/converted to mech. I would "definately" go with the circlip for serious roller work. I just don't believe I will need more than oem., to do the job, in a racing Rover eng. I have Buick V6 "dogbones" on the way and will pursue the Buick V6 hold-down arangement, perhaps spliced/welded. We shall see. roverman.

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?

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.

Paul, I think this forum is it. Previous conversions were mega $'s , skirted mech. rollers. Race car , only stuff. roverman.

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.

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?

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.

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.

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?

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.

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.

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.

Jim, Could you tell me the URL for the Buick web ring with the roller conversion information?

Thanks.

Wait. I found it.

http://www.v8buick.com/showthread.php?p=1549390

http://www.turbobuick.com/forums/engine-tech/224567-fwd-roller-non-roller-cam-parts-gn-motor-w-pictures-3.html

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

Post from Jim in the Big bore thread. It's a good one...

QuoteHey Art, I bet you could take some weight out of that roller cam and make the engine a little lighter. Wonder how much trouble it'd be to run a hole down the middle of it? Come to think of it, with your Rotus heads you might save a whole lot of weight that way.

Jim

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...

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.