807-03 engine into r12

Back in the day I remember seeing a couple of r16 bell housings that had been modified by adding a bulge for the crownwheel on the other side and modifying the clutch release arm to work in a similar way to how a 12G one did (similar to r17 but on opposite side). Then you use a 16 input shaft and bell housing with your r12 box. It’s a lot of stuffing round, and the ratios in a r12 box are all wrong for an 807 anyway. Also. People talk about the r18 block having the same mounting castings as r12/15/17, but that’s not my recollection (I may be wrong but remember stuffing round with one to get it done and eventually just modifying an 807 to take the 18 sleves).
 
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Back in the day I remember seeing a couple of r16 bell housings that had been modified by adding a bulge for the crownwheel on the other side and modifying the clutch release arm to work in a similar way to how a 12G one did (similar to r17 but on opposite side). Then you use a 16 input shaft and bell housing with your r12 box. It’s a lot of stuffing round, and the ratios in a r12 box are all wrong for an 807 anyway. Also. People talk about the r18 block having the same mounting castings as r12/15/17, but that’s not my recollection (I may be wrong but remember stuffing round with one to get it done and eventually just modifying an 807 to take the 18 sleves).

from questionable memory the ratios in the 352 box are the same between R12 and R17 (or near enough). They share the same box number, different suffix, thank you Renault.

There you go. I think your problem with the blocks was that you were trying to use a 17 block in a 18. The other way around works because the 18 block has more bosses cast than the 17, or at least that's my experience.
 
You can do it if carefully grind out a hole slot R12 box taking great care with main gearshaft oil seal then, manufacture an aluminum cover to weld on inside of gearbox then sealed with expoxy resin. Worked well in my motorkhana special. R16 front reversed on to R10 with R12 box so all going 4 forward gears and reverse. Used an offset pivot point to increase clutch throw.

This is the only way to make a R16 bell housing to bolt up to a 352-** transaxle.
 
Back in the day I remember seeing a couple of r16 bell housings that had been modified by adding a bulge for the crownwheel on the other side and modifying the clutch release arm to work in a similar way to how a 12G one did (similar to r17 but on opposite side). Then you use a 16 input shaft and bell housing with your r12 box. It’s a lot of stuffing round, and the ratios in a r12 box are all wrong for an 807 anyway. Also. People talk about the r18 block having the same mounting castings as r12/15/17, but that’s not my recollection (I may be wrong but remember stuffing round with one to get it done and eventually just modifying an 807 to take the 18 sleves).
from questionable memory the ratios in the 352 box are the same between R12 and R17 (or near enough). They share the same box number, different suffix, thank you Renault.

There you go. I think your problem with the blocks was that you were trying to use a 17 block in a 18. The other way around works because the 18 block has more bosses cast than the 17, or at least that's my experience.

The 352 transaxle in the R12 & R15TS & R17TL have roughly the same gear ratios, the real difference is the diff ratios. R12 is 3.77:1 & the R15TS 7 R17TL is 3.55:1
 
The 352 transaxle in the R12 & R15TS & R17TL have roughly the same gear ratios, the real difference is the diff ratios. R12 is 3.77:1 & the R15TS 7 R17TL is 3.55:1
Yeah. R12 does around 4000rpm at 100kph in 4th whereas with 17 box/diff ratio you’ll do 100kph at around 3400.
 
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from questionable memory the ratios in the 352 box are the same between R12 and R17 (or near enough). They share the same box number, different suffix, thank you Renault.

There you go. I think your problem with the blocks was that you were trying to use a 17 block in a 18. The other way around works because the 18 block has more bosses cast than the 17, or at least that's my experience.

This was for an r17 and was an 18 block. The 17 motor mounts are pretty much in the centre of the block. The 18 are further back. There are a few castings in the 841 type r18 block but (from the experience I had) they don’t work with the mount plates of r17 (think the oil filter side can be made to work but the starter side is a fair way off. I have also heard it said that very late r16ts 807 motors had the provisions to mount in r17... I have seen a few r16 motors and haven’t seen one that does, so I suspect this to be a myth.
An r18 block will however, bolt into an r16 or a europa.
This is all pretty pointless though, as nobody has a spare r18 block. I was looking for one a while back and couldn’t find any.
 
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We've done dozens of these and never used any R16 bits.

Sometimes we were stuck for a bell housing and modified a 16 to fit but everything was from a 17.
R15/17 are built on a R12 floor pan so everything just bolts in, (there just a 2 door R12 with a bigger motor).
4Sp R17 box will go straight in but 5 speed needs a bigger floor hump, that's why we prefered to use R12 automatic body shells. R12G and R17G have bigger humps than standard but not as big as automatic shells.

Use radiator (can't use R12 radiator because it flows the wrong way and is to small) so use R17 with all the standard R17 hoses. R17 carby will hit the bonnet, either run side draught or you can remove the heat plate from the bottom of the R17 carby and it will clear, good luck in cold weather.


Alternator and brackets need to be 17 not 16. Driveshafts are just standard R17, unless your not upgrading the brakes then R12 will do.
R12 Gordini was really a 4 door R17 Gordini and all the suspension and brakes were the same, Gordini's have disc rear but 17TL/15TS use R12 wagon rear brakes.

I'm the RCCV inspector and 30 years ago when these were more common I would be asked by Shannons to inspect cars to make sure they had the correct ventilated front discs ( from a 17) and the large rear drums (or disc) and the thicker sway bays from the 17. Then it would be insured as an R12 Gordini replica.

Good luck with yours, trying to use R16 parts is definitely doing it the hard way and I think you need a 17 or 15 donor car.

I have a very rusty low milage R17TL sitting in my backyard and a good rust free R12 sitting in the shed, I've been hoping the two would mate but I have two many other projects and no time anymore.
 
I’ve been what seems like halfway through this exact project for 6 years now. I did it once before (many years ago) using a 16TS engine and a 4sp 15TS box as you’re proposing and it involved a lot of fab and a lot of problem solving, so I feel I’ve made all the mistakes already.

The latest version of the project is doing as everyone has suggested and I have used a donor 17 for everything I need, and for everything I already had, now I have spares. With a complete 15/17 donor car, it is quite a straight forward process, but as David said, you’ll likely need to source manifolds and side draft carbs or go down the injection route, which is what I’ve done, but this opens up more cans of worms and the project snowballs like mine.

Its just my opinion, but honestly, if I was starting this project again now, I’d source the bigger brakes (I’ve come across the hubs, rear caliper mount brackets, calipers, etc, in separate ads online), get the bigger swaybars from signature, find a UN1 box, get some driveshafts made and drop in an electric motor for an EV conversion, but I’m also a little disillusioned with the project just at the moment.
 
We've done dozens of these and never used any R16 bits.

Sometimes we were stuck for a bell housing and modified a 16 to fit but everything was from a 17.
R15/17 are built on a R12 floor pan so everything just bolts in, (there just a 2 door R12 with a bigger motor).
4Sp R17 box will go straight in but 5 speed needs a bigger floor hump, that's why we prefered to use R12 automatic body shells. R12G and R17G have bigger humps than standard but not as big as automatic shells.

Use radiator (can't use R12 radiator because it flows the wrong way and is to small) so use R17 with all the standard R17 hoses. R17 carby will hit the bonnet, either run side draught or you can remove the heat plate from the bottom of the R17 carby and it will clear, good luck in cold weather.


Alternator and brackets need to be 17 not 16. Driveshafts are just standard R17, unless your not upgrading the brakes then R12 will do.
R12 Gordini was really a 4 door R17 Gordini and all the suspension and brakes were the same, Gordini's have disc rear but 17TL/15TS use R12 wagon rear brakes.

I'm the RCCV inspector and 30 years ago when these were more common I would be asked by Shannons to inspect cars to make sure they had the correct ventilated front discs ( from a 17) and the large rear drums (or disc) and the thicker sway bays from the 17. Then it would be insured as an R12 Gordini replica.

Good luck with yours, trying to use R16 parts is definitely doing it the hard way and I think you need a 17 or 15 donor car.

I have a very rusty low milage R17TL sitting in my backyard and a good rust free R12 sitting in the shed, I've been hoping the two would mate but I have two many other projects and no time anymore.

I have saved the auto transmission hump from my last auto Virage (they are quite large).

If you don't have the right radiator hoses you can cobble together a hose from right angle hoses and some aluminium tube quite easily.

There is no clearance between the top the the carby, I have removed the heat plate from the bottom of my carby to gain a few mm in clearance. I have not suffered any performance problems in cold weather which surprised me.
 
Angru. R16 TX blocks fit both 15/17 and 16's they have the additional holes to suit both forms of engine mounts. As 16TX's never were sold in Australia it is unlikely you would have seen one.
 
Ok Brains Trust(s) Did we work out what the K4m needs re bell housing and gearbox's? (with intention for a 12/15/17)

Asking for a friend..
 
Ok Brains Trust(s) Did we work out what the K4m needs re bell housing and gearbox's? (with intention for a 12/15/17)

Asking for a friend..

R12 (well anything usually mated up to a Sierra/Cleon iron block).

R15/16/17 (well ones mated up to an 807 style alloy block) need an adapter plate but would allow a bigger flywheel/clutch to be used. Might as well go F4R or EV if doing an adapter plate though.

if anyone wants to swap a R17 bell housing for an R12 one let me know.
 
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Some great information here to consider.
It's looking like a complete parts car may be making my way soon! Thanks to this active community.
I'm guess this 807 will await the next project or may end up being a fair donor engine.
I'll try to update with my progress as it developed 🙂
 
Cheers Jensen. I had thought the K4m would require the bigger flywheel clutch similar to the 807. The more you know..

*gumtree searches intensifies*
 
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