Modest upgrades to an R10

R

R4gene

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Tadpole
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Jun 1, 2021
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Lidsdale
Waiting for a recently purchased R10 to be delivered and was wondering what upgrades are worth doing. As far as I can tell it is still stock standard. I intend to use the car as a daily driver, no city driving all country.
Any advice, tips or pitfalls greatly appreciated.
 
Much depends on how brisk your country driving will be.
 
Able to keep up to speed limits mostly without having other drivers waving their fists at me 😂
 
What model? Round eye?

A good stock R10 is more than capable to keep up with modern traffic given our speed limits though a five speed 'box never hurt anyone. But that's a long and far from modest story.

I would suggest you invest in some good quality tires first thing (assuming there is absolutely nothing mechanical to need attention) and take it from there.

One thing to do if you like that sort of thing is an electronic ignition module to replace the points. There are many to choose from, all pretty much the same. It will improve your starting and running because it will keep the timing spot on (if all else is in good nick; if not, it won't do much).

If the car has been laid up for some time, you will have your work cut out. Brakes, bearings, suspension, steering, fuel system, ignition, clutch, the rest of it.

Like I said, get some good tires and try as is, ideally on an extended drive and the car will tell you what it needs. Just check fluids before you set off.

Bonne chance.
 
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I would also consider making the rear suspension straps a little bit shorter than standard. If the car has been standing and the brakes needs work, then remove the rear brake limiter at the same time and replace it with a T-piece.
Frans.
 
Bustamif said:
An R12 motor, new shocks, 5.5 inch wide wheels, maybe lower springs.
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That R12 engine is a bit feeble, need this

911.jpg
 
Here is one I prepared earlier, it has the lighter magnesium case than the alloy one above and one off Andial angle port heads. I was thinking of another Floride, more space for a Porsche engine and better airflow to the engine bay than R10.

The R12 motor would be easier than the RSR Porsche engine (below) for rego in NSW.

I agree with Frans suggestion regards the straps and rear brake valve. Good modest mods for cost effective improvements
 

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Hi :)
Hi plenty of simple suggestions. Here are mine. They ride a lot better with a bit of weight in the front. That stops the front suspension from topping out on our poor roads, say two bags of cement or equivalent.
Never over-drive it as standard they can be unforgiving at the limit. You are better off with sliding the rear than getting ultimate grip. Smaller wider rear wheels was common to lower the rear and widen the track.
But an enjoyable car and enough go for normal use. Those engines respond to normal old fashioned 'hotting up' quite well but parts to do that might be hard to get now.
Jaahn
 
Good point about weighing the front end up a bit, but also keep in mind they will go sideways on dry tarmac at 40km/h. Which means you have enough front end grip but little rear. This is with standard width tires.

The fun of a lightweight car.

As for more power, I think the first thing I would do is change to a better flowing carby, say a 32/36 DGV and make sure the intake is nicely matched to the head. Tuned well, the DGV is enough for upwards of 150HP so more than plenty for the stock engine.
 
Definitely R12 engine, even in std form. 14” wheels seem to be a good compromise. 13’s give better acceleration and arguably 15’s better road manners if you can get the wider 10S wheels but having tried all combinations I’d go with 14’s as a better compromise.

I wouldn’t bother with extractors whether you go with a side draft Weber or more original 10S or R12 downdraft, the std R12 manifold will work just as well. A mandrel bent exhaust and Lukey muffler will give a nice bark and performance.

Agree with electronic ignition suggestions and much of what else has been said.
 
A selection from the above & some further thoughts.

1. A standard R10 1108 engine is not a slug but: a standard 1289 or 1397 engine from an R12 is worth having. But: the conversion is not a bolt out & bolt in simple task. There is some fiddling with clutch & transaxle input shaft. Seek expert advice.

2. I concur with 14" rims. Easiest way to do this is to use R16 rims & have a wheelwright sever centres from rims, reverse rims, weld over valve hole & drill new valve hole. The result is a nice strong 4.5" wide rim which will take 175/70-14 tyres. My current favourite 14" tyre is Pirelli's P6; it has a nice stable tread, a structure which is responsive to pressure tuning, benign limit behaviour & decent grip in the wet. Don't fuss too much if you can't get rims with the safety ridges, don't fit tubes and try to get the later rims with centre holes if possible. 175/70-14 has an almost identical circumference to the standard 135/80-15.

3. Do shorten the droop straps to 330 mm (R8G length) & replace the rear pressure limiting valve with a simpleT piece of tube. The rear brakes will do more work & front lock up in the wet is near abolished.

4. I disagree with the suggestions for electronic ignition. I was an enthusiast for these conversions but am now disenchanted. Failures have been:
- R8 with warm 1.4 & Bosch distributor. Crane Cams Hall effect kit fitted & failed; another fitted & failed. Gave up. Fitted a Gammatronix transistorised ignition module which uses points but only as switches (found on eBay UK).
- Djet with warm 1.4 & SEV Marchal distributor. Igniter 11 Hall effect kit fitted & failed. Converted to Gammatronix.
- 4CVG with warm 1.4 R5 Alpine/Gordini engine & Ducellier distributor. Hot Spark Hall effect kit fitted & just failed. In at my dyno guy now having Gammatronix unit fitted.
- Moke with warm 1330 engine & Lucas distributor. Fitted (in 1980) with (what was then called 'Optospark') module with infra red "chopper" set up in distributor & remote unit. Unit failed after about 5 years but had a lifetime warranty & was replaced (now relabelled 'Megaspark'). No further failures & still in use.

5. Fit (locally available) Koni R8G dampers. Leave on softest setting plus half a turn (this only adjusts rebound). A bit of fiddling at the front extending the height of the bottom mount to accommodate the shorter damper shaft & at the rear (removing a shroud to fit in the spring & turret) but still modest fiddles.

6. Don't sling a sack in the front. With a near standard motor you add too much weight. But, unless you will carry big loads in the front boot, consider removing one turn from the front coil. This raises the front spring rate &, much like a larger front anti roll bar, changes the F/R balance of roll resistance in a beneficial way. It also mildly improves top speed.

If you like the results & wish to do more immodest fiddles my next list would be:

quicker steering, front radiator, electric fan & electric water pump, camber compensator & the usual engine fiddles if you have a 1.4 fitted by then. None of these involves dramatically hard engineering changes.
 
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Assuming the OEM springs are linear, I am not sure I follow the logic of the spring rate comment.

Why do you think the spring rate would change if one coil is removed?

I accept there may be other considerations specific to the car that may be at play (e.g. the spring angle might change resulting in a lower spring loading, which has the same effect as a higher spring rate).
 
Lots of good ideas here. I'd add that in round numbers, with standard tyres on 15" rims (in my case 145-15 Michelin XZX) you do 4,000 rpm for 100 kph. It'll do that all day but is on the busy side, noise-wise. The original 1100 engines were prone to failure of the top ring land at high mileage, allowing little bits of piston ring into the combustion chambers. That would point you to a new sleeve kit at the least if the engine is original.

There are different views, but we found a 40 kg bag of cement in the front of the R8 greatly improved cross-wind stability when ours was used on the Freeway in Perth a lot. Cement bags are now 20 kg.

Mr 4cvgordini had poor results with Hall Effect kits. I had the opposite experience with the one branded "Hot Spark" but you are still relying on the centrifugal (mechanical) advance system and the pivots wear out in the end (although they can be rebushed). I fitted a 123 electronic distributor in the end, a couple of years ago, and the performance seems no different to me but it starts MUCH better and runs more smoothly on a slight throttle opening. Not cheap. The original system works perfectly well when set up properly but I agree with him about the Gammatronix unit - I have a 6V one on my 4CV and the beauty (for me) is the minimal current switching from the points, which show no marks on the faces after some years.

Regarding brakes, several of us in WA use silicone brake fluid, and since you'll perhaps do a full overhaul you could take the opportunity to change. Not everyone agrees but I've found the complete lack of corrosion and long life very appealing. When I dismantled my 4CV brakes after 25 years with silicone everything was perfect, full stop. With the R8/10, corrosion behind the seal grooves in the callipers is the issue. I still have a tiny leak somewhere - not a drip to be found - but if you clean them up super-carefully when re-sealing they behave OK.

I've had Konis for many years on the R8. Totally agree that this is worth doing. PM me if you'd like detailed information about the lower mounting brackets, as there are indeed two types and you need the later ones for new Konis.

The car might still have its original windscreen - if so remember it is not laminated, and one day you'll get that stone....... Some people have fitted two-speed wipers using R12 components. I haven't bothered but do have a foot switch that gives one sweep and rewired very slightly to give automatic parking.

Back in the day, people fitted R12 or Fuego tombstone seats for comfort and neck protection. First find your seats though.

Don't hit anything. They are not strong by modern standards!

Good luck with it.
 
I have owned 4 R10's. 1 standard, 3 altered. Competed in all the usual club motorsports, sometimes well and other times not so WELL?.

The 10 that stood head and shoulders above the others was the dead standard one! (y)

Note: I too now would shorten the rear drop straps as suggested. :)
 
BIGRR said:
I have owned 4 R10's. 1 standard, 3 altered. Competed in all the usual club motorsports, sometimes well and other times not so WELL?.

The 10 that stood head and shoulders above the others was the dead standard one! (y)

Note: I too now would shorten the rear drop straps as suggested. :)
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Funny that. The design engineers maybe knew what they were doing?

I've experienced a dramatic improvement in turn-in and wet road behaviour going from 135-15 ZX to 145-15 XZX on the standard 4" rims. The next generation tread pattern is good and my new ones are the special batch made ones, so I think a modern structure and compound.
 
schlitzaugen said:
Assuming the OEM springs are linear, I am not sure I follow the logic of the spring rate comment.

Why do you think the spring rate would change if one coil is removed?

I accept there may be other considerations specific to the car that may be at play (e.g. the spring angle might change resulting in a lower spring loading, which has the same effect as a higher spring rate).
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I am not an engineer but this is what I take the story to be:

Imagine a torsion bar. Fix one end & apply a twisting force to the other. The bar accommodates this force by distorting along its length. Lots of molecules & their bonds are involved in this accommodation. As distortion increases the bonds resist it more (until rupture occurs).

With a shorter bar, & for a given twisting force, fewer bonds are accommodating the force & the bar is initially distorted more & the bonds involved thus enter the greater resistance zone earlier.

I no longer recall where I got this from & I would be delighted to have someone more technically competent in the area supply an antithetical analysis. No doubt there’s an “explainer” or three out there in the web. I haven’t yet looked.
 
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