Dunlop R5s and rim width.

cbbear · Post by **cbbear** » Wed Jul 25, 2012 1:02 pm

Hi, little help please gentlemen.

Dunlop 600-15 R5s. I seem to remember that the early Autocar road test used R5s for the high speed run. Anyone know if this was the tyre size and whether they were on 5 or 51/2 inch rims?

Any negative thoughts regarding fitting these tyres to an early 3.8 E, just for nostalgia? (Other than price of course). I've been told they're now "all weather" compound.

Best, CB.

Post by **Heuer** » Wed Jul 25, 2012 1:24 pm

More info here: http://www.longstonetyres.co.uk/page/jaguar-e-type Give Dougal a call at Longstone and he will give you a run down on what tyres are best. There is a video on the site discussing the merits of the different options for the S1 including the Dunlop's.

Jaguar specified 5? wire wheels but offered 5.5? wheels, on the rear only, for racing. You can fit 6? wheels but only a 5? wheel will fit in the spare wheel well. Many people fit modern low profile tyres, typically 70 or 65 section, and they do look good but there are compromises. The already limited ground clearance will be about 1? lower, the lack of compliance in the narrow sidewall will make the ride firmer and the extra width will make the steering heavier. The lower profile tyres do not fill the wheel arches so whilst the car now looks good from the front/rear it looks odd from the side. Modern tyres are designed for cars with variable camber geometry which the E-Type does not have so directional stability and cornering can be affected. If you want wide tyres use Michelin XWX on 6? wheels which were period fitments to the S3 V12 cars (although they had power steering) and are a better match for the E-Type's dynamics. They are readily available although not cheap. The best way to improve an E-Types handling, precision and feel is to fit solid wheels instead of the wires. Wide wheels upset the cars' balance.

I have tried 6" wheels with Yokohama and Pirelli tyres and the driving experience was, frankly, dismal. I went back to 5" wheels with Michelin XVS 185VR15 and the car is a delight to drive. Smooth, controllable, finger light steering and the ability to adjust the cornering angle with the throttle - a complete hoot! And at three figure speeds you can take your fingers off the wheel and it remains arrow straight. The wide rubber made my E-Type tramline like crazy, steering lost its feel and speed bumps were a nightmare. Forget taking your E-Type to the gorgeous back roads of France if you have low profile tyres fitted - it will be quicker to walk through the villages

Many people are moving back to 185's as the tyre of choice if you want to drive your car rather than look at it. Best 'upgrade' you can make to an E-Type.

As for crossplies you will find you can be even more of a hooligan on roundabouts and traffic free roads but you will lose the margin of safety that radials bring to the party. Probably best avoided if you are going to seriously use your car.

cbbear · Post by **cbbear** » Wed Jul 25, 2012 2:58 pm

Thank you David, I agree with everything you say. But I still wish to fit R5s for nostalgia sake. Can you or anyone help resolve my question? Thanks to all.

Best CB.

Post by **Heuer** » Wed Jul 25, 2012 3:26 pm

The high speed runs were done using 9600 HP with 5" wheels and Dunlop R.5 racing tyres set at 40psi. The R.5 tyres were a very hard compound and made the ride harsh, hence they were not fitted to production cars. They were also chosen because they were narrow (reduced rolling/air resistance) and had a larger circumference than the road tyres. After the runs 9600 HP was refitted with RS5 tyres and it was used as the press hack.

Nearest you will get today are these: http://www.longstonetyres.co.uk/page/64 ... p-rs5.html

cbbear · Post by **cbbear** » Wed Jul 25, 2012 4:16 pm

Thanks David. For the record genuine Dunlop R5 600-15, same size as originals (I think), are available and in stock here:

http://www.classictyres.com/item/364/60 ... unlop-race

Best M.

Post by **Heuer** » Wed Jul 25, 2012 4:35 pm

I think the clue there is the word 'Racing' writ large, so probably not going to give decent all round performance on the road. You will notice they also do not have a speed rating. The Dunlop RS5 6.40 on 5" wheels is the road going version of the R.5 6.00 and should give you all the fun you desire. If you ordered your E-Type with racing tyres Jaguar supplied R.5 6.00 x 15 (5" wheels) on the front and R.5 6.5 x 15 (5.5" wheels) on the rear. Longstone sell the latter. According to Dougal:

"Racing tyres are normally designed purely for racing, and no compromises are made for road suitability. However due to popular demand and in Dunlops acknowledgement that many drivers of vintage and classic road legal race cars prefer to drive them to and from events on their racing tyres. Dunlop have carried out a complete test and development program on the Dunlop Racing Tyres resulting in "E" marking accreditation on certain vintage and classic Dunlop racing tyres. These are the 16" & above Dunlop racing R5, R1, 3-stud & 5-stud pattern Dunlop racing tyres. The L and M section Dunlop Racing tyres unfortunately are NOT road legal."

So you are stuck with the RS5's I'm afraid.

cbbear · Post by **cbbear** » Wed Jul 25, 2012 6:56 pm

Thanks David. They told me would be fine for road use - not good, eh?

Thought it might be a nice idea though - R5s, Castrol R................

Best, CB

Post by **Heuer** » Wed Jul 25, 2012 7:22 pm

Thanks David. They told me would be fine for road use - not good, eh?

Which is why I recommend Longstone Tyres. Dougal will tell you the truth, even though you may not want to hear it!

Add some Castrol R to your petrol tank and you will get that gorgeous smell! I would be interested to hear how you find the RS5 tyres though.

JagTheOne · Post by **JagTheOne** » Fri Jul 27, 2012 11:51 am

Hmm, castor oil. What if people can not only hear me coming but also smell my car passing by

What do you think about combination of Castrol Classic R40 oil and XK engine?

I was trying to find service interval for this type of oil but without success. I found lot of number between 5000 to 10 000 miles or every 6 months... Do you know something more?

Thanks
Martin

Post by **Heuer** » Fri Jul 27, 2012 12:22 pm

It is a single grade oil designed for racing whereas you should be using a multigrade oil (e.g. 10W/40) for road use, mineral for the first 5,000 miles and then semi-synthetic. The R40 is not ideal for road use as if you are stuck in heavy traffic and the oil gets really hot your oil pressure could drop dramatically. A race car is constantly moving at speed so it gulps lots of air to keep things reasonably cool but even a full race XK engine will be using 10/40 nowadays. As I say, if you want the smell, put a cup full of Castrol R in your petrol tank.

According to Castrol themselves:

"It is difficult for us to give accurate advice on what frequency of oil change would be needed if you were running on Castrol R40, but it could be as low as every 1,000 miles. Castrol R 40 is a very good lubricant under certain circumstances, however it is relatively unstable and will therefore tend to promote the build up of deposits in your engine. The instability of Castrol R means it is also not recommended for long term storage, so if you were going to store your car for 6 months, we would suggest you consider filling with new Castrol R at the start of the storage period and draining and replacing with new oil at the end, before using the car again. If storing for longer than 6 months, it may be worth switching back to a modern mineral, part-synthetic or full synthetic.

We are often asked about the best way to obtain the Castrol R odour and from our discussions we are aware that many people add a small amount to their fuel. Just how much seems to be an inexact science, but generally the less you can get away with the better. You might like to start with 1000:1 fuel:R ratio (50ml of R in a 50 litre fuel tank) and see how that works, adding more oil if there is insufficient effect. I would suggest if you get as far as 100:1 (500ml of oil in a 50 litre fuel tank) and still aren?t getting the effect you want, you might want to re-consider the benefits versus the downsides!"

Unfortunately the smell will always be behind you so you will not get the benefit. Someone suggested putting it in your lawnmower fuel so you can get pleasure from a chore!

JagTheOne · Post by **JagTheOne** » Fri Jul 27, 2012 6:30 pm

:? Whatever... Thanks again David.

I think I'll start to use it in lawnmower since it is the only way for me how to enjoy it for now.

My car is waiting in the garage for restoration. Man I can't wait for that day when I'll start the engine... But I think it will take few more years to earn some money and build some decent shed where I can take it apart.

Martin

PeterCrespin · Post by **PeterCrespin** » Sat Jul 28, 2012 10:40 am

If you want to know what Cazzie R does to an engine, look at the outside of a well-used and not fastidiously-cleaned frying pan or baking tray. Thick, sticky oxidised goo :-(. It's not even all that easy to clean off the outside if it leaks on a hot area. Also, putting significant amounts in your fuel is going to crud things up eventually as it is not mega-soluble in fuel so can separate on standing. It is not low-ash so will promotote carbon build-up on pistons/rings, valves and chambers as well.

I loved it in my race bikes but they used comparatively small amounts, whereas doing the number of changes you'd have to do in an XK would be ruinously expensive. In the 2-strokes I never had to change the oil of course, so that was not an issue, just the price differential.

You can't just swap to and fro with R either, because mineral/castor react. You can only really switch totally safely in either direction following an engine rebuild. Again, not a big issue on a race bike unless it was oil-in-the-frame like my Metisse. But do you really want to strip your XK when you get tired of taking out a mortgage to change gallons of oil every month or two? You can't even take it to the dump like normal oil as it will ruin their recycling batch.

If you've got an alcohol-fuelled high-compression racer then go for it. R is very slippery (high lubricity) even by today's standards. But for a road car or even petrol racer nowaday's, there is no rational reason for using it in preference to the modern oils with their additive packages or synthetic base stocks.

Nice dream but probabvly time to wake up and smell the coffee instead - it's easier to wash up. I did try it in the fuel tank of my first D-type but that didn't work very effectively so I stopped experimenting.

Pete

david muir · Post by **david muir** » Fri Aug 17, 2012 1:46 pm

cbbear,
have sent you P.M.

David Muir

adam · Post by **adam** » Sat Sep 01, 2012 5:49 pm

Hi just fitted some dunlop RS5s, so far so good i will let you know when ive tried them for longer.
Adam

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

The 'E' Type Forum

Dunlop R5s and rim width.

#1 Dunlop R5s and rim width.

#2

#3

#4

#5

#6

#7

#8

#9

#10

#11

#12

#13 Dunlop R5s

#14