Renault straight eight engine anyone..?
- Thread starter 56 Fregate
- Start date
The exhaust valves are in the block. The 6 push rods are for the OH inlet valves.
The exhaust passages had a beautiful straiģht shot from the valves to the perfectly round ports.
The carbs were on the opposite side of the engine to the exhaust, so it was a crossflow design as well.
I see. Thank you.
Used in Series IIA Land-Rovers, that engine's burned exhaust valves were not uncommon in my experience.
Really interesting I've always thought. RR did the same but I'm not sure who else did.
But wait there's more.
I'd note from this delineation there is a brake servo attached to the rear of the gearbox (M) and is driven from the final drive. If you remember the sad and sorry Monastella from a while back which was missing some of the key parts. https://www.aussiefrogs.com/forum/index.php?threads/1929-monastella.140492/
I'd note from this delineation there is a brake servo attached to the rear of the gearbox (M) and is driven from the final drive. If you remember the sad and sorry Monastella from a while back which was missing some of the key parts. https://www.aussiefrogs.com/forum/index.php?threads/1929-monastella.140492/
Hehehehe! How the times have changed. I see an updraft carby hanging off the side like some forlorn irrelevant ancillary and also, is that something else they're driving off the (!) gear driven (?) alternator (I suspect a dynamo in fact) shaft? Looking where the outlet is going, I would hazard a guess it's an oil pump?
Water pump.
Oh, I thought the cover it outlets into was the pushrod cover.
Well, cool, nevertheless.
I mean you see how you can take just one part off and fix that instead of having to dismantle half the car to get to the part you need to take care of. Oh, the good old days.
Well, cool, nevertheless.
I mean you see how you can take just one part off and fix that instead of having to dismantle half the car to get to the part you need to take care of. Oh, the good old days.
The Land Rover's 6 cylinder although IOE and the same capacity as the Rover 90 and 105 six cylinders, are actually a different engine. The Land Rover had a 7 bearing crank whereas the P4s had a 4 bearing crank. You can see the difference in the head gasket, the P4 cylinders are spaced in pairs to accommodate the 4 main bearings where the Land Rovers cylinders are spaced evenly as there is a main bearing in between each cylinder.
Even the local engine rebuilder's parts books reckoned they used the same head gasket, clearly they are different.
Well back to the original engine. Remaking a straight 8 engine will require a crankshaft so here is a suggestion. 
These guys weld together broken cranks so I suggest "just" welding together two 4 cyl cranks and VOILA an 8 Cyl. Then all you have to do is cast the block to suit and then the head ?? What could go wrong there. The essential ingredient seems to be a carton of fags for the workers ?? Gees some great basic machining, setup, and welding skills seen here with minimal equipment. The mobile phone in his top pocket lives a charmed life too !!
Jaahn
These guys weld together broken cranks so I suggest "just" welding together two 4 cyl cranks and VOILA an 8 Cyl. Then all you have to do is cast the block to suit and then the head ??
What could go wrong there. The essential ingredient seems to be a carton of fags for the workers ?? Gees some great basic machining, setup, and welding skills seen here with minimal equipment. The mobile phone in his top pocket lives a charmed life too !!Jaahn
Hmm! I'm not too sure it's that easy but what is easy is to make a youtube video of your capabilities without any verification, call me Thomas.
There's a chap in USA who has a stack of used straight eight parts including cranks. The Americans seem to value their old Yankee iron and they keep stuff. Start with a crank of known integrity is the go, then make the block to suit and then the head etc. Do you reckon it could be done..?
There's a chap in USA who has a stack of used straight eight parts including cranks. The Americans seem to value their old Yankee iron and they keep stuff. Start with a crank of known integrity is the go, then make the block to suit and then the head etc. Do you reckon it could be done..?
Even if you dissected 3 Four cylinder cranks to loosely look like an eight the pins and bearings wouldn't necessarily be the correct size for said application particularly the rear bearing.
I recall about 30 years ago reading a magazine article where a US builder joined two small block Chevy V8s together to create a V16. The cast iron blocks and heads were cut, chambered and welded together and the steel crankshafts were welded together. The only thing I don't remember is was what they did with the camshafts?
I found a short online article on it.
I found a short online article on it.
Sweet 16 Chevrolet
Built by the father-son team of Al Mathon Sr. and Jr. by merging two blocks, two steel crankshafts and four cylinder heads into a single unit. The engine has nine main caps instead of the normal five. The rear main on the block up front is shared with the
www.museumofamericanspeed.com
... I wonder if Chev used cross plain cranks, if they did it would be very smooth indeed.
The small block Chevy has a 90 degree crank.
Well of course it could be done ! The time factor is the problem like most ambitious projects. I think you have the skills. As you already know the planning is the answer and then the reality check on the ideas and plans.Hmm! I'm not too sure it's that easy but what is easy is to make a youtube video of your capabilities without any verification, call me Thomas.
There's a chap in USA who has a stack of used straight eight parts including cranks. The Americans seem to value their old Yankee iron and they keep stuff. Start with a crank of known integrity is the go, then make the block to suit and then the head etc. Do you reckon it could be done..?
You could just use two 4s and connect them 45deg out of phase(like the V16) and have an unusual firing order. Would not matter with an 8. I would not worry about the rear bearing size as the 8 would probably put out less power than the individual 4s. I am not sure what you had in mind there
But if you had a made 8 crank then that is easier and more reliable in the long run probably. That sets the dimensions too so half the planning is done ! Are they available with usable rods, pistons and bearings too ??
Those rods in the picture are spindly old style but would suit a low reving side valve.Jaahn
I'm toying with you. I already know I can do it but just because one can do something doesn't mean they should. I mean whats the benefit in doing so and is the benefit equal to the effort, that is the question. I already know I can do the complex castings in alloy. Vintage parts like rods and pistons are available. I already have a 1936 Dodge 6 to use as a master for critical measurements like bore and stroke, the shape of ports and combustion chambers etc. The layout of a Dodge six is the same as most of the other manufacturers including Renault except a Renault straight eight is a mirror reverse to the American brands. So my Dodge six gives me most of the info I need including oil/water passages and strutting requirements. Remember I think that casting an iron block would be out of my reach but an alloy block is definitely doable at my facility. I can make the patterns with ease, I have a mill and lathe, primitive though they may be but still quite usable and I know how to use them. Drilling long holes for oil passages would be a steep learning curve and there are still some gaps in how the thin iron cylinder liners would behave in an alloy block.
So in summary: If I acquire another Dodge six engine which are easy to get and quite cheap, I then have enough con rods, main bearing caps, oil pump, water pump etc etc. to complete the job. NOS valves and bearing shells can be got and I can find a crankshaft in USA and would then have to manufacture a camshaft in reverse polarity to suit the Renault configuration which will be easy enough. That should keep me occupied for the next decade..easy.
But is it really worth all the effort. Remember the golfer who spends his life trying to perfect his swing, for what benefit. That is the question.
So in summary: If I acquire another Dodge six engine which are easy to get and quite cheap, I then have enough con rods, main bearing caps, oil pump, water pump etc etc. to complete the job. NOS valves and bearing shells can be got and I can find a crankshaft in USA and would then have to manufacture a camshaft in reverse polarity to suit the Renault configuration which will be easy enough. That should keep me occupied for the next decade..easy.
But is it really worth all the effort. Remember the golfer who spends his life trying to perfect his swing, for what benefit. That is the question.
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@56 Fregate I'm guessing you already have this article given your interest in the subject?
It's an interesting read for those who haven't seen it though.
www.motorsportmagazine.com
It's an interesting read for those who haven't seen it though.
Rare car: a vintage straight-eight Renault
When I heard that a straight-eight Renault was to be found in this country I thought that it might offer material for another White Elephant safari.
www.motorsportmagazine.com
Thank you, yes I have seen it and there is a Youtube piece on it too somewhere.