Engine and Transmission Tech

Ok so the idea of Lotus 907 heads on a Rover sounds like a pretty cool project. I know Art is considering doing this project. I hope he does so I can see it happen vicariously. So I looked around a little and learned a lot in a short period of time. The bore spacing is correct, the head bolt holes are at the right width but wrong place for the block so the block needs some modifying for that. Some fabrication for the intake and exhaust.

I welded up my own headers. It's not easy but mostly just time consuming. It's actually kinda fun. The intake could be approached the same way with tubes and webber carbs or injection bosses and throttle bodies.

So not a lot of guys are gonna want to build this but I thought I'd start a thread to discuss the possibilities.

Just for fun I searched ebay for 907 heads. I found a whole engine for $100. LOL!

[cgi.ebay.com]


Here's a couple pix of a guy mocking up the heads on the Rover block:




It looks like you could just mill off the webs on each end of the lifter valley and bolt a plate on there. It might actually add some strength to the block. What do you do with the lifter oil galleries? Like just block the passages from the pump? Then there's the timing belts. Should they use separate belts? Like one for each side? I'm assuming you would use the crank pulley from the 907 and adapt it to the crank nose. Would it spin at the right speed for the cams?

Just trying to get the ball rolling.



Edited 2 time(s). Last edit at 11/10/2009 02:49PM by NixVegaGT.

Yea suure Nic, like "set the hook" in the old guy. Actually, (2) 907 crank spockets(1 for each head), an maybe Vega timing belts so "poly vee" on backside drives the accessories as tensioners. Gut the cambearings and "shrink-fit" a heavy walled/steped , alum.tube, where cam was, "notched" for killer strokes. This will beef the main saddle area upstairs and add oil resevoir to feed the mains? But wait, for a few $'s more... why not VVT? Stock 907 rod weighs 928 grams! Top fuel anyone? Problem with 2L. is not enough tork, with puny 2.75" stoke, huh? Plenty of recip. weight, 1" dia hvy. wall pins. I think we can lighten-up a little here. Nice, right side headers already available. Need to duplicate-mirror image for left side.Use nipped Rov. bathtub, why-not. Heads are soo stong, you could tie them together but not needed. Block is stronger with "tube" and no valve train inside.West Coast RacingCyl.Head is claiming 305cfm.@ 28" and .450" lift.2.3L. produces 265hp.,na.on gas.Port velocity is good through-out the range. Eight cyl. should do better than double as a 4.6L,(reduced parasitic losses). Plan is for my 74 JH. roadster. JHPS already"hates me". I'm going to DESTROY resale value! Let the spewing begin. roverman.

Plenty of valve area but those intake ports look kinda small. Can't see the exhausts but likely as not they do too. Something needs to be done about that for sure. That mismatch on the studs might be the biggest problem though, depending on where they hit on the block. The deck isn't thick enough to just drill and tap new holes. Since the lifter galleys feed the mains you can't just block them off unless you run external lines to the mains but since an external pump will be needed, why not? Maybe feed them using Art's cross bolts. With all that welding going on. might as well just weld a plate across the top of the lifter valley too.

Jim

What you are saying is the path the oil takes goes through the lifter galleries so we can't just block off those galleries. SO we use a blank like Art's talking about for the cam bores. That seems easy enough. Then we need a crossover of some type. We could use holes through Art's cam blank. We could put a hole through every journal location. Still gotta deal with the lifter bores. Do we just press in blanks there too? I guess that would work fine. It doesn't need to be leak proof just needs to keep the pressure up, right? Nothing's moving here so we don't need to worry about stuff wearing out.

Good point about the oil pump. We're probably going to have to need an external pump because of space needed for the timing belts, right? I suppose we could ditch the front cover all together. Use a crank triggered EDIS for distribution. There is probably not room for the oil pump because of the timing belts, right? Then we have to deal with making some type of housing for the front seal.

OK Art. I've got to do some decoding of your post so bare with me. I skipped over the VVT for now. We should talk more about that but later. Are you saying that we could use the Lotus piston and rod? That would be with the stock 2.8" stroke, right? I'm thinking we could do this for a bigger displacement though. Not like the ones I've been discussing in the stroker options thread because it would be cool to really wind this thing up. Get some major revs out of it. What kind of RPMs are they running with that West Coast motor?

Backing up: So we drive the oil pump off one timing belt and the alternator off the other one. Make sense?

Ok what the hell is "nipped Rov. bathtub"??? Sounds like pornography. LOL.

Plug the galleys feeding the lifter bores, won't needum. Feed oil to cam replacement tube/oil resevoir to priority-fed-mains. Easy take-off from this to feed heads. I belive a belt driven Mopar(gerotor) sbm.,oil pump should be adequate. Less bleed-off than all those, "leaky" lifterbores. push rods and rockers. Lotus, rod,pin and piston-dumb. Waay too heavy.We want around 600 gram sbc rods and lite pins/pistons. Jim and all, wer'e "used" to looking at 2 valve ports for adequate flow. they need to be "big", because there port velocity doesn't measure-up to 4 valve specs. Granted the 907 ports need opening-up for maximum flow, larger vales are reasonably priced. "If" the "worked" 907's do indeed flow 305"@ .45" lift, thats enough .Nic, "nip the bathtub", it's not a "video", trim the stock, sheet metal, intake gasket, sometimes refered to as "bathtub', to fit up/to the 907 heads. Kinda like "wildcat" does. I'll have to check where max hp. was-thought 6,500-7k. Drive a distribtor off end of a cam or belt, frequently done in aftermarket. We don't have "tons" of valve train loads trying to split the valley in this build.The block likes this.This motor will be heavier, 3 more cams and the heads are beefy. Big stroke, no problem, but kinda like chosin a cam/cams, how big you need? Nic, now when you say,"we're", you mean vicariously-right? Stay tuned, it mite get bumpy,roverman.

I guess I do mean vicariously but I do say "we" because I want to build this engine! It captures the imagination.

Thanks for the clarification. The "bathtub" makes sense now. What do you think of eliminating the front cover? I bought this water pump for my engine build. Cheap and mounts anywhere:

[www.daviescraig.com.au]

You can control the temp with a thermal switch. Nice. SO remote water pump, remote oil pump, cams up in the heads so there's no need for the front cover, right? On my Rover block, opposite the starter there is a little port that faces the flywheel. It seemed to me that there could be a crank trigger setup using the flywheel... Just thinking out loud.

I thought the late Rover crank trigger was back there? I need to look at the late Buick V6 rear drive blower arrangement. Distributor or accessories out or way for a way short engine.Why have front tim. cover if doun't need? Belt guards, a good idea. This motor wants' injection, slideplte-best. roverman.

Your cam replacement tube is going to get complicated. For one, if longer strokes are to be considered it will have to have reliefs cut in it for the rods to clear, and may need them for the shorter strokes also. Full cam bearing diameter is going to stick out farther than any cam lobes you could get. And there's no point in filling a big tube full of oil, that's just trouble looking for an excuse. I actually kinda liked Art's idea of using hollow cross bolts to carry oil to the mains but it might be a challenge getting enough oil in there that way, still, just a function of pressure I suppose as it's a hydraulic system. Could run it right on up there as far as needed to get the flow. Also all those lifter plugs would have to be necked if you expect oil to go around them. That's another invitation for disaster having all those plugs in a vital system. Probably better to shrink a thinwall stainless tube into the galley full length and then drill it back out as needed. As I recall the hole is drilled from the main up past the cam bearing and into the lifter galley. So after tubing the galleys just re-drill those holes. If you want some sort of a one piece cam replacement use a billet and turn down the lobe areas to the base circle at the same time that the plug sizes are machined and put o-ring grooves for sealing so that it doesn't require massive force to press 5 plugs into place at the same time. The area between the o-rings can be recessed for oil flow between the galleys.

Access to the oil galleys can be front or rear and there is some logic in plumbing to the rear, as well as using external plumbing for the pick-up, although tieing in at both front and rear would be an option. An oil pump driven by one cam belt is not a bad idea, provided it used a toothed pulley and was therefore on the inside of the belt. Alternator could be either way. A simple aluminum plate with a seal for the crank could also act as a backing plate for the timing belt covers. Matching to the pan shouldn't be difficult. Rover did in fact use a notched flywheel for crank trigger. No reason the starter ring gear couldn't be used as well. I think Mega-Squirt could handle a 300 tooth wheel last time I looked so it's feasible.

Jim

Using the flywheel teeth as trigger is pretty cool. EDIS is out then because it uses a missing 36-tooth rig. I like the idea of turning down between the journals. I suppose it might be easiest to just index some cam bearings and press those in to block the cam oil galleries. That would be pretty easy. What do you guys think? It wouldn't do anything for load sharing but we could do that differently anyway..

The thinwall sleeve in the gallery is nice. I really like that idea. Then use some sort of different crossover. I'm with you on the lifter plugs about having a bunch of them sitting in there waiting to fall out. I'm not tracking on the lifter plugs needing to be necked. Is that to get oil to the cam journals? Well that's not necessary anymore if we loose the crossover in the cam plug idea. If you're talking about obstruction in the gallery side isn't it already like that with the lifters in place normally? Not really an issue if we ditch the lifter plug idea anyway.

Ditching the lifter plugs is a real good idea for more than one reason. Longitudinal flow down the galley depends on the necked area of the lifters because the lifters bisect the galleys and a straight sided lifter would block it off. I think. Might want to check that. Anyway visualize the restriction in oil flow down the galley past all of those lifters, even with the necked down area. No wonder the rear rod journals get starved. So with the sleeve in place all those 8 restricters per side just magically go away and the rear bearings get full pressure.

Some of the mains are fed from one lifter galley, some from the other. So both have to have pressure and flow.

Jim

Back to my post on 08, heavy wall tube means any wall thickness less than solid. Milling (2) flats-90deg apart between journals-easy for machinist. This is a beefy, heavy walled, main webb reinforcement.Dry ice-it preheat block and you got plenty of clearance/time to install. Plug your solenoid controlled ,Accusump into this galley,bore to be determined, and "viola", you got the oil right were you want-it to prelube for start-up. I think I count maximum (5) plugs for lifter galleys? Why is there oil even going there? Back-tracking from mains? Ok lets put small thread-in plugs bottomed-out to prevent? I think with this lay-out, "side-oiler" is not needed. Isn't this fuun? roverman.

Art, isn't the block already pretty stiff in that area, what with the cast areas that contain the existing oil galleys? How does a big chunk of metal down the middle add anything? I could see the sense in something like a girdle plate but especially with the cam and lifters gone the lifter valley seems plenty strong enough already. As far as plugs to block off the lifter galleys from the mains and cam bearings, you'd have to put a plug in the bottom of a small (3/16-1/4") hole nearly 5 inches long which opens into a larger channel. No step to cut threads for a plug unless you drill the holes out larger. Taps long enough to do that job are scarce and pricey and it's too small for a tapered pipe thread. So not as simple as it sounds. Maybe you could drill through the top of the lifter galley and go in from that end, I'm not sure. If the holes don't line up pretty close to centered it could get nasty.

But as long as we're doing... might as well bore the cam bores out so they are all the same size, that way you can use a uniform stock size of hollowbar. I have no idea if you can get aluminum hollowbar in TGP (turned, ground, and polished) or if you can get it with the over 2" OD and something like a 1/2" ID but if you can that might work and you could then hone the block to fit. Incidentally, the trouble comes, not from the amount of time you have before the plug warms up, but from contact with the bore. For something like this, with 5 journals and the plug packed in dry ice it'd still be a real good idea to heat the block in an oven to get as much clearance as possible and even then try to hold the interference down to .001" Getting it in and getting it properly positioned front to rear and rotated correctly so that your flats line up in the right place and your oil holes mate up properly will still provide you plenty of opportunity for error, at which point you will have created wholesale scrap. Not that it can't be done, but getting it right the first time? Maybe, maybe not. And about that plug... sounds simple to you maybe, to me, not so much. Expensive, hard to source, easily damaged material, needing end fittings (lathe operation) and "simple" milling that isn't all that simple. First you have to determine the angle between the flats, then the longitudinal position and depth. Then you have to set up a mill with a degree head, and either it has to be a pretty good sized mill or you will have to reposition the work at least once to get both ends of the part. Next you have to have oil holes to communicate with the main oil drillings in the block and some go right and others go left so you have to get that part right and it has to meet the passage properly. That doesn't sound very simple to me, especially compared to just turning o-ring grooves and clearances on a bar of round billet, where none of the tolerances has to be very close. But if you don't like the idea of using tubing to block off the lifter bores and you're dead set on adding a third oil galley maybe you could use hollowbar instead of solid and cross drill it into the oil grooves between the o-rings. Another thought, I bet you could find drill rod that could be shrink fit into the lifter galleys, thereby eliminating them entirely. No threaded plugs that way, but hey, maybe it'd stiffen the block! ;-)

Jim

Guys,

Don't know if this schematic of the rover oiling system helps, it appears to me that you could just plug/weld the oiling holes to the cam bearings and lifter gallery and the oiling to the mains would still be retained and with better pressure.

Don't have the benefit of a bare block in front of me so I could be wrong.

Kevin.

If this is true then the mains are fed through one side of the lifter gallery. SO we don't need to worry about crossing over. I'm thinking Jim's solution of pressing a stainless sleeve done the right gallery would work best. Just leave the rest open. We could drill the holes for the mains in the tube first. Drill them larger than the main ports so indexing isn't mega critical. Or drill them after like Jim was saying.

Seems like the simplest solution there. On the front seal. How do we do that? Usually the seal mates with the balancer housing. Do we have it seal on the nose of the crank instead since it needs to go behind the timing gears?

I was thinking about the head oiling. The best way to tackle that would be to make an external bypass. Like a braided ss line, right? We could take off the back of the block maybe and run a couple -4AN lines to each head oil gallery. What do you guys think of that idea? I guess we could just use a small manifold of fittings as it feeds the main gallery. I was just thinking it'd be nice to feed the mains first instead of the other way around. I guess it probably doesn't matter though.

On the cam timing. How does that work? I mean will the valves be timed right if we just put the 907 cogs on the crank and cams? I mean will they be spinning at the right rate? On that note do the cams need to be billet or something?

For the max RPM it seems like the limiting factor wouldn't be mechanical as much as flow. I bet this thing could really spool up. What do you think?


Thanks for participating in this thread. It's pretty fun for me. I hope it is for you guys too.



Edited 1 time(s). Last edit at 11/10/2009 11:04AM by NixVegaGT.

This comment may not be relevant but, generally 90 degree double overhead cam per bank V formation engines are too wide to fit in a car such as an MGB and the others on this site.

Nick,

The way I read the drawing is that the mains are fed after the cam bearings and the lifter bores are fed by the gallery to the right of the cam in the schematic, this feed then goes up to feed the valve gear in the rover heads, the feed to the left bank is not shown.

If the drawing is accurate then i see no reason why the holes in that gallery which feed the cam bearings cant just be blocked with threaded plugs or possibly welded but that might cause stress problems. You would have to a hole of suitable size in the bottom of the bearing housing to allow direct access to the oil holes but that should not be a problem.

The lifter gallery could just be blocked at an appropriate position either to maintain the feeds to the heads or block it if so desired.

Jim,you appear to have a good working knowledge of the oiling system, is this a viable proposition?

Unfortunately I can't open the pictures showing the 907 heads, any way they can be opened in the normal way.

Kevin.



Edited 1 time(s). Last edit at 11/10/2009 02:17PM by castlesid.

Yeah. Sorry about the pix. I'll go back and fix that momentarily.

Quote:

This comment may not be relevant but, generally 90 degree double overhead cam per bank V formation engines are too wide to fit in a car such as an MGB and the others on this site.

Ok. It is a British V8 though. OR you could just make the car wider, right Jim!? LOL. (that is what Jim did to his car.) Seriously though, are you saying we should talk about how to deal with that in this thread? Ok. I'm in.

How about swapping the heads from side to side and run the exhaust over the top into a turbo. We could build 180º headers to feed the turbo then! Then feed the intakes with logs on the sides. Just barely slipping under, between the fender wells and the block. I think the intakes would point down then. Anybody?

I guess we don't necessarily need to feed a turbo with it though. Maybe we could squirrel up the header pipes and run one big tube down one side of the engine at the rear.



Edited 1 time(s). Last edit at 11/10/2009 03:16PM by NixVegaGT.

Nick,

We'd make it fit, actually from memory the lotus heads aren't that wide compared to some modern engines.

Kevin.

OK first a couple of corrections. The 215 does in fact feed all five mains from the left side galley, (the 340 feeds at least the rear main and I think one, maybe two others from the right side) and the galley is offset enough from the lifter centerlines that a straight sided lifter or plug *should* cause no significant restriction although they certainly would cause turbulence. The feed is to the left side lifter galley then down past the cam to the mains. Transfer from the left to the right side galley is through the front cam bearing, to the groove in the front cam journal, around the cam, and through the cam bearing into the right side galley so isolating that galley is very easy. The feed to the left galley comes out just in front of the #2 cylinder and makes a 90 degree turn into the front cover. Tapping into that galley at that point would be fairly easy. Drilling from the top to plug the galley end of the drillings to the mains would have to go right through the web reinforcements so not a real good idea there, and the communicating holes to the cam journals are small and would need to be enlarged if the feed was through a tube in the cam location, but they could be easily blocked by "incorrectly" installed cam bearings for main feed via tubed left side galley. head oiling could be via either internal or external lines.

Nic, my car is only wider on the outside, inside it's no different.

Jim

Ok so on a 215 block we can ignore the "right" (when looking at the front of the engine) gallery all together. On a later block, like the 340, maybe even the Rover blocks, we need some type of crossover from the "left" gallery to the "right". Is that what you're saying?

On the main "left" gallery (at least on the 215) we could put your stainless steel tube idea and redrill from the main side to open it back up again to just the mains. That would effectively block everything else and we could then feed the heads externally or something. You were thinking like tubes in the lifter gallery with fittings off the main gallery, right?

BTW everybody should be able to see those pix now.

On the oil pump we're talking about using something like this?




I was thinking I could order a 907 head gasket and see where the holes end up but my engine is totally assembled now. Anybody else willing?



Edited 2 time(s). Last edit at 11/10/2009 04:23PM by NixVegaGT.