Engine and Transmission Tech

Anybody ? I was getting "zero" response from serious cam post, so I'll try one more time. Late Rovers running roller chain, belt or gears ? Perhaps a crafty person, "converted", early set to late ? What have you 4.0/4.6 L., people done ? roverman.

Have to look into it. I assumed all Buick/Rover engines used the same timing chain. Whatever part # Cloyes or Edelbrock should work for all.

I think the standard roller chain will fit, checks have to be made as i have seen one or two touch the cover at the top

Yep, all interchangeable.

Clan, seriously here, we're comparing, early with snout/dis. gear, to with-out snout/gear.When you look at "late" cam, you'll see. roverman.

I've got an SA Gear double row chain for my Olds 215, probably from JC Whitney. I'm not at the point of assembling those parts yet. I do have a 4.0 but that's a pretty low priority right now. Other fish are frying.

Believe it or not Roverman, the TR8 and MGBV8 guys retro engineer it to go back to the distributor. Dumb I know! That is why the TR8/SD1 timing cover is worth its weight in gold. You have to go out and find a timing cover, oil pan, buy an intake and carb, buy headers, buy a nice ignition system, Mallory distributor, cam and lifters, and reuse that horrible cam gear and oil drive system. Lots of waisted money if you ask me. That is why I want to do the turbo so badly. On the surface the FI system for a turbo seems like a lot of money, until you start to weigh it against all of these other parts.

Kevin and clan, the roller cams I'm having made,(10), are late nose. Problem seems to be, finding a cost effective, hi-performance drive, for same. Regarding FI and turbo's, can't blow through , oem. FI with upgraded controller/fuel curve ? I definately like the idea of crank driven oil pump, even if it's external. I suspect if cam gear was driving dizzy-only, would be non issue. roverman.



Edited 1 time(s). Last edit at 03/22/2010 10:52AM by roverman.

Art,

If I'm understanding you, the main problem with the later style rover cams with provision for the retainer plate is that the bolts for the plate can foul certain types of timing gears, the one that creates most problems are the vernier types but this can be addressed by slimming down the heads of the bolts which is not a problem in that they are not under a lot of stress.

Depending on which bottom end you are using, the crank snout will need the slot lengthened to use the longer woodruf key to drive the oil pump.

Some of the later front covers are quite short, dont have a dimension but they look similar to the SD1/P5-6 or buick215.

Kevin.

When I was racing the TR8 with the 3.5, I used to go thru cam and distributor drive gears like crazy. They don't like sustained high revs. I'm guessing the cam would walk out as the gears wore. The car would experience loss of power and even see misfires at higher RPMs, because the timing would change as the gears wore. Once I went to the 4.0 cam retainer and slotted the back of the gear to sling more oil, the problem went away. I am really looking forward to using the crank driven oil pump and distributorless ignition to get away from the earlier set up. I never even considered the thought that the timing chain would be a problem.

Todd, The gears we're never intended to hold the cam in position. Taper on the lobes were, (wishful thinking).The higher the rpm, the less contact, that 30" radii on bottom of lifters,has upon the very slight taper on the lobes. I'm thinkin, you were'nt using thrust button ? roverman.

Your right. There wasn't any provision for that on the earlier Rover covers. On the Buick and Olds covers, there is a bump where the cam is. For some reason, Rover did away with them and it took them 30 years to figure out it was an issue. In hind site, I am sure that is why my cam would "walk", thus screwing up my timing and chew up my gears. I talked to Tim Lanocha about the timing chain. He has used the double roller on the SD1, the intermediated cover that has the distributor holes but blocked off, and the later slim cover with no provision for the distributor. He doesn't remember having any issues on any of the covers with regards to using the timing chain. He did mention that you need a spacer under the front pulley bolt if you use the 4.0 crank with the early covers.

Some X bolted blocks dont have a retainer, same as the earlier SDI blocks, I would assume the cam skew gear creates thrust against the block holding the cam in position, One performance thing we used to do was fit a thrust button in the end of the cam and adjust the buton so it is about 0.002" 0.004" clear of the cover which effectivly stops the cam walking about.
Overall the new style pump and front cover shorten the engine about by about 2" over the short Buick/Rover P5/6 nd nearly 32 over the rangerover verson

Couple of pics of the later cover, Im sure I have posted these allready