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/serious rollers-pleeze?
Update, it's a new year, let's get it in gear! 1,677 "peeps" on this subject and (3)? ,people have said their interested?? Howard Cams is "workin a quote" for qty. 10 and 25 billet rollers. If I get enough positive feed-back from "this" forum, I may jump-start this. 215-340 and "noseless"-only. 350 sbb. folks already have rollers from TA ,and TA hasn't responded for this application.We know all about the low cost, other components , we're running out of excuses not to. Stay tuned, it will get-"bumpy". roverman.
Edited 1 time(s). Last edit at 01/11/2010 09:10PM by roverman. |
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/ non-serious $'s
Update, Under $300. ea. based on qty. 25 in a run, "noseless" are less. All will accept retainer plate. How bout "bolt-on", a distributor gear/spacer, onto "noseless" cam, for those who want dizzy? Let's get "bumpy". roverman.
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BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6468 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Serious Cams
Looks like TA is making a little progress in that area, as Mike Jr says they are waiting on a Rover roller cam to test and if it checks out they will order.
Jim |
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/loaner?
I have (3) in stock, but I "loaned" MikeSr. a stg. II V6 billet roller, about a year ago- no word. Much as I'd like to help..........
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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/loaner?
I have (3) in stock, but I "loaned" MikeSr. a stg. II V6 billet roller, about a year ago- no word. Much as I'd like to help..........
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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
Update. written quote, Flanged, finished complete,(5) in a run= $355. ea. No flange, finished complete, (25) in a run=$295. ea.
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Re: Serious Cams
By flanged, I assume (making an ass of me and u) that you mean the cam has the distributor drive extension hanging off of the front of the cam. True?
I'll have to raise some money to buy some cams. I'm going to try to help get the volume up enough to get a full order. I'll sell the extras. Are these cams finish ground to specification? Will they be surface treated after grinding? Is it safe to assume (there's that word again) these will be compatible with those nice, new, Delphi V6 roller lifters that we buy off of eBay? I'll get in touch with Art via PM when I have raised the funds. |
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, you know of an "inflection" occuring in oem, Rover head flow? I believe by lifting valve faster and more lift will keep the valve in the "sweet spot"/flow under the curve-longer? I'm not convinced that what works great in a sbf. will in a Rover. The more we lift the valves, the more they are unshrouded from chamber and cylinder walls,(their not centered in chambers). Clan, yes, when I say "flanged" = identicle to 215-340 Buick, oddfire V6 Buick and RV8's with distributors, BUT will accept RV8 retainer plate! I will make at least (1) to take sbc(3) bolt drive for belt. I don't "trust" that little notch in"noseless" cam for serious work. We will need "exact" lobe lift and LSA., and lift per deg. of cam rotation,(we're not limited to .007"/deg. now), for rough and finish grind. Finish grind will be .005"-.010" removal per side, occurs after carburizing to depth of .040". This should be adequate depth for hyd. rollers and mech.'s excepting RV8's in TF/TA drags? roverman.
Edited 2 time(s). Last edit at 01/16/2010 09:23PM by roverman. |
Re: Serious Cams
Art, I understand that after about .400" of valve lift the BOPR ports don't increase their flow by much. I've seen that inflection on Ford Y-block heads and Studebaker V8 heads. So the trick is to maximize low-lift flow to get the port flowing that much sooner (I think). With the roller lifters the valve timing can actually be shortened and still have a very good Area Under the Curve (AUC).
The down-side with roller cams would have to be reversion. Maybe that's why you always see factory HiPo roller cam engines using long intake runner tuning (TPI Chevy, SEFI Ford 5.0L, SEFI Ford 7.5L); it's probably because of the wicked air pressure pulses from snapping the valves open so quickly. The long runners would isolate the other cylinders from 'seeing' the pulses, and carbs have a bad time with tuning when the reversion is severe. But I'm not an expert on this by any stretch - I'm just guessing. So, between increasing the intake valve size a bit, pocket porting the intake ports, removing any abrupt angles in both ports, and a roller cam, we can get big improvements in low RPM torque and still have ok power in the mid-range. I'm modeling my specs on the Ford 5.0 SEFI HO engine because I drive one and it's got very nice low-RPM torque, excellent fuel economy at highway speeds, and uses electronic port fuel injection. The 4.0 that I got has port fuel injection. I think the stock 5.0 cam has something like 114 or 115^ LSA. But the 5.0 has short rods (5.09" on a 3.0" stroke). With the low rod ratio, the piston gets to the top of its travel later and the exhaust and intake events are naturally closer, resulting in more reversion from exhaust pressure. Also, with a wide LSA, valve overlap is reduced and less fuel escapes during overlap, which improves economy and reduces emissions. The rod ratio is higher on stock BOPR engines. My Olds has a 2.8" stroke and a 5.66" rod and the piston spends more time near the head during overlap, so blow-down will end sooner and reversion will be reduced, so I'm assuming that I can pull the LSA in a little tighter, to 112, to pick up some more mid-range torque. The Rover 4.0 has an even longer rod and it will have even less sensitivity to LSA and overlap. But I'm only taking a swag at these numbers. I'm completely open to suggestions about valve timing suggestions. My goal is for a daily-driver friendly engine in a LBC with a 5 speed. I have an Olds 215, a Rover 4.0, and I also have a Rover 4.2 crank that I might put into the Olds. Engine sizes will all be in the 3.5 to 4.0L range. The Olds heads have the valves centered in the cylinder better than the Buick-based heads, so the shrouding issue is different there, but it might not make much difference in my application. |
BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6468 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Serious Cams
Art, I would be but I have a custom grind in my 340 that is yet to be tested and crank clearance in this motor is critical so I'll have to pass this time around. But I do hope it becomes available as a regular part. Better check with the boys over on the Buick board. Some of them may buy in, and if they could get them with the 350 journal sizes several of the 350 guys would I'm sure now that the TA heads are almost done.
Jim |
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
Jim, Thanks for response and I understand. Only response I got for V8 Buick folks was for LS 1 pattern on 350 sbc's. As I see it, those folks already have resonably priced cams from TA. I think it's a good thing to have more than one supplier of a particular type of cam. I suspect more people will, "come on board", once"others" provide concrete results. Thanks, 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/getting started
I'm ordering #8620 mat. blanks, tommorrow. Paul Menton will have (5),completed cams, should anyone be interested. roverman.
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Re: Serious Cams
Art, I haven't yet come up with a ramp rate for the cams. I'm thinking that because the base circle is relatively small, and because the lifer bores are cast aluminum, I'd be looking at something that's lower than the typical Ford Windsor or Chevy SB ramp rates.
I was going to mine the Buick V6 site for potential information about cam specs, but searches of the web on terms such as 'cam ramp rate', 'cam lift rate', etc. never did produce any numeric values, only references to the subject as an abstract concept. BTW, our friend who is building a turbo V8 Triumph might be interested in a cam with zero overlap and a wide (114 -117) LSA. Seems like a roller cam would be perfect for a turbo application. |
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 and Tony, I'll ask Fri. bout lift rates and what "masters", they have in-stock. Good new is, as round lobe blanks, only thing final is "flange/no flange".For obvious reasons, we want to keep base circle as large as possible,while achieving enough lobe lift, and smaller than bearing #4. I "assume", you-guys, have found a swinging deal on double roller chain drive for "no flange" Rover ? Rollin on a riv..... 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
Nic, thanks, but no thanks. Just buy a cam when your ready. Paul and all, I put a deposit in, to build (10) blanks, (6)flangeless and (4) with(215 style).I want to use 2.0" dia. on flange and a Rover retainer plate. If someone has a problem with this...tell me NOW. Contreras is going to spec. an oem. sbf. roller cam coming into shop, prior to being ground-hotter. "Rollin on a riv."....roverman.
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