Serious Cams

Started by roverman, November 21, 2009, 09:41:58 PM

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roverman

Isn't it about time? I suspect if "forward" thinkers from this forum and say, V8 Buick(sbb), ask a company "like" Doug Herbert etc.-not a plug," how much to make say qty. 10-50 of ROLLER billet cams, with/with-out stepped bearing dias'"? These companies have many cam" masters" specifically for the sbc. hyd/mech. lifters,(the lifter of choice). Volume talks and they "retail", #8620 material, rollers at $230., just an example. "If" there were enough interest, I could build the tooling to readily, "bronze bush" our beloved motors, making low cost sbc. lifters suitable. Anyone? roverman.

pcmenten

Yeah, I was wondering when the BOPR engine was going to enter the 80's and get a reasonable set of roller cam hardware. The lifter bore is the same as the Chevy, so that end of the hardware shouldn't be hard to come up with. What's left? The camshaft?

They make link-bar lifters, so just use those lifters on a roller grind of your choice. Yet, there's nothing out there that's off-the-shelf.

The shaft rocker system should be rigid enough to bear the higher spring rates needed for roller lifters. Roller rockers would be a help. Beehive springs will reduce the spring pressures needed. Seems like a slam dunk, but I guess things look easy to me because I don't really know how they get done.

Regardless, I'd like to see something like this happen. Art, I'll commit to buy a cam or two, just tell me where to send the money. BTW, my application would be hydraulic roller cams for emissions-legal engines.

Edit; a post-script - on the subject of rigid rocker shafts, I heard an idea from Ted Eaton over on the y-blocksforever forum. Gun drill a solid bar to make a heavy walled rocker shaft. Then chrome the shaft for a durable finish.

Doing this one-at-a-time would be spendy, so it might make sense to have a place like that rocker arm rebuild company job the project.

NixVegaGT

We'd have to get our British cousins on board with us. I only just finished this engine with a nice Erson cam from Woody. On the 360 I'd be in though.

BlownMGB-V8

The BOPR engines have the oil galley too close to the bottom of the lifter bore to use a standard roller lifter so it's necessary to use a "skirted" design where the roller is recessed into the body of the lifter. These are more expensive to produce due to more complicated machining processes and the prices for them tend to be higher. That would be the first thing to source. It has been done. TA sells a billet roller cam for the 350 which isn't much different. But it'll set you back nearly $1500 for the cam and lifters.

Jim

NixVegaGT

Sweet. Are those like the ones GM was using back in the 80's? I think I remember seeing some that looked like that in my Dad's Olds Diesel the 3rd time we were rebuilding it. What a pile. Anyway, maybe we could use something like that??

nalle

Jim, is it something like these http://static.summitracing.com/global/images/prod/large/lun-72400lun_w.jpg ? I am trying to understand the design you are talking about.

castlesid

The Wedge shop do a custom Erson roller cam and the correctly shrouded roller followers for the princely sum of $1759.00

I have seen the shrouded roller followers from other sources, TA Performance and elsewhere for reasonable money so if one of the cam producers was prepared to do a custom roller cam for sensible money it could be worthwhile, might be worth asking comp Cams as they do make roller cams.

rollercam.jpg

Kevin.

BlownMGB-V8

Those are the type, as Kevin posted. Notice how the rollers are recessed up into the body of the lifter. Without this feature there will be huge leaks when on the lobe. Also I'm pretty sure Olds used larger diameter lifters but you might check it.

Jim

NixVegaGT

That's exactly what they looked like. I wonder how big they are. I think my Dad's probably got a lifter laying around. It was a pretty cool looking part. Fun to fiddle for the ADD mind with while talking on the phone. I'll give him a call and find out what the diameter is. Can't hurt.

hoffbug

I believe Crower also has the correct roller lifter ( solid) and the ability to custom grind.

roverman

Forum Folks, My main point was, once the lifter bores are bronze bushed, we run any @##$^^&&**, sbc. lifter we want-Cheep! I suspect this will lead to reduced bleed-off and pressure loss oil from lifters bores,(better fit when hot), plus some beneficial pre-stress of the bores? BOPR. lifter dias. are same as sbc. @ .842",(also our rod width).I haven't done a bleed-off check of the OEM sbc. hyd. roller lifter yet,anyone? It looks a "lot" like the roller pictured except for tie bar. Want cheep mech roller lifter? Take hyd. guts outta  sbc., put the "lid" back in to bottom, add longer push rod and "viola", you"ve just made a lighter/stronger mech. lifter. T&D made thick rocker shafts for B/R. Not cheep but good. I know of no rocker mfgr' that makes "rollers" with "needles" on shafts. Crane and Kenne Bell had alum. bores. This kind of $, I want needles in there.Since TA moved their valve angle to 13 deg., this "should" have made room for needle/roller rockers. Can we get a "want" list together and get ball/roller, goin? roverman.

NixVegaGT

Lets do it! No answer from my Dad yet but I suspect the lifters fit the stock lifter bores for a 350 chevy. I'll keep digging. Good idea about homemade solid lifters. COOL!

castlesid


roverman

Ok, So if we've taken the plunge to use sbc lifters...why not lube thru the push rods? "If we do this, can we not use sbc roller/needle rockers on a "smaller" dia., solid shaft? Probably strong enough with-out "end supprts". IF you must have end supports, why not each end of the head, simpler and the strength is already there. While we're on this sbc. stuff, we need to stop comparing our valve spring needs to that of sbc's. Most of us will not be using 2.02 and 1.6 dia. valves. Most of us will not be running the radical "ramps" as raced in sbc's. For most of us, our valve train requirements will closely resemble Buick V6, after-market parts.Let's narrow this down. Lets get a consensus.Let's focus and then go-for-it. roverman.

NixVegaGT

I've already converted for oiling though the pushrods for my engine. It just took getting hollow push rods and blocking off the oiling ports in the head.. I like the idea of going with a solid shaft. I think a hollow one might be stronger... Wait that's true for bending but we're probably talking about more shear force than bending force. Lighter though.

SO you're talking about those shaft conversion thingys the Chevy guys use, right? The little shafts that bolt into the stud mounts or whatever? Just ditch the little shaft thing and use one shaft per side mounted on the existing perches. We could make mounts that resemble the D&D gussets for the ends of the shaft...


roverman

Nic-et-all, yes. Gives us cheep/good rockers with ratios uo to 1.7/1. Remember our small base circles for 3.85" strokes? In leiu of support bracket on ea. end of current design,  affix a "support plug" in the end/rocker cover support wall. Make the "new" shaft reach this. More -simple, I like simple.

BlownMGB-V8

That'd work well with an o-ringed cast valve cover... now who can we get to make those for us?

Jim

hoffbug

Peep these:

[www.kmjent.com]


Nic. Are those 289 for the whole set of do you need 8 pairs of them?

I know some folks poo-poo on T&D but I love their stuff.
You have choice of steel or Aluminum and choice of rocker ratios as well...( the steel rockers isnt available for the SBB/Rover yet)
 since the Buick 215  stuff uses the stands on the heads its about 1/2 the price of a SBC setup. T&D says they can do up to a 1.7 ratio for the rocker, their shafts are solid gun drilled.. and due to the design of their rocker you can either oil through shaft like factory or through the pushrod. Like a SBC...

 I run their stuff on the Chevelle and its very high quality.. see below.






Nic..Look at the horrible finish on the rocker body next to the adjusting nut.. And this is on a site that they are trying to sell something!


roverman

I suspect on our sbb/Rovers, rocker loads will be approx. 60-70% of sbc's with 2.02/1.6 valves? I'm thinkin the "bargin" roller rockers have a good chance of holding up, provided we supply a good shaft and mounting? Comp.Cams stainless rockers at $259. I think that beats "Wildcat"?  I'm ready to build shafts. What say? roverman.

roverman

Whoa! I just pressed-apart a "Pro Form" needle/roller, rocker for sbc. Bad idea! Not made to disassemble, rebuild/etc. Some of the needles-gone. Shaft is stepped-down ea. end from .720" to .466 dia's.(bearing id).Unless someone finds rockers with a straight shaft through them, this won't fly. I'm considering counterboring alum rocker for bigger needles, but this rocker is already weakened by huge slot in middle. Anybody? roverman.

BlownMGB-V8

Look into aluminum extrusions. There is bound to be an extrusion company that has a shape that will work for rockers. (maybe even with a near net size bore) Slice them to length, drill and ream the needle bearing bore, slot and drill for the roller and pin, drill and tap for the adjuster, and all you need is the shaft. Don't pay $700 a set, it's one of the easiest engine parts to make.

Jim

roverman

Jim, sounds pretty simple. How much do you want for 1-2 sets with-out shafts? roverman.

BlownMGB-V8

Depends on how much you want to do Art. Find the extrusion and the hardware and I can do it fairly cheap. If I was making some for myself, same thing. But I'm not. So, how much do you want to do yourself?

Jim

roverman

Jim and all, My first choice,still digging, is to use a sbc. design with a one dia. shaft. I simply have too much on my plate, "907", Silver State Classic, etc., to build rockers from scratch. Maybe their out-there. I'm waiting to hear back from "Herbert".   Thanks, roverman.