Chim/Griff owners: What tyres are you running?

[Chris71]

So, what tyres are people running on their Griffiths and Chimaeras?

The main reason I ask is tyre availability: As I understand it, it's hard to find 15" tyres in the correct speed rating for road use (as opposed to track days).

How big an issue would it be if you ran marginally under-rated tyres to get the correct size for the original wheels? You'd be pretty hard pushed to exceed 149mph in a standard Chimaera on a UK track I'd imagine(?) and I don't intend to go quite that quickly on the road.

Those who have switched to larger front wheels - can you restore the original rolling radius by switching to a lower profile? Also, I've heard it suggested that OEM tyres were quite stiff so you might get the same compliance by fitting something with softer sidewalls in a lower profile?

Finally, what are the pros and cons of fitting equal diamater wheels on both ends?

Also, can people suggest what make/model of tyre you'd recommend for all-round road use (particularly any to be found in the standard sizes)?

[.Mark]

Chris71 said:

So, what tyres are people running on their Griffiths and Chimaeras?

Got Toyo T1-R's on the back, great tyre. Got Dunlop Sport 9000's on the front, don't like them. I did check with the fitters and they are the correct speed rating. Had them a while now so it is entirely possible that availability/ratings etc has changed.

[Chris71]

.Mark said:

Chris71 said:

So, what tyres are people running on their Griffiths and Chimaeras?

Got Toyo T1-R's on the back, great tyre. Got Dunlop Sport 9000's on the front, don't like them. I did check with the fitters and they are the correct speed rating. Had them a while now so it is entirely possible that availability/ratings etc has changed.

Are they standard size tyres running on the regular 15" front / 16" rear wheels?

ETA: And to all the other people who voted for standard size wheels and tyres on the correct speed rating - where are you buying them from?

Edited by Chris71 on Monday 22 November 11:56

[450Nick]

I used to just run toyo T1-Rs on all four corners. Couldn't care less about the speed rating!

Now run 16" imolas all round with R888's on on some days, and 17 (front) 18(rear) wheels with low profile T1-R's on others. Stuck on the R888's at the moment though as the others are bald! That said, if I were buying again, it would be R888's every time.

[rigga]

17" all round with Falken 452 rubber...... but when i purchased mine it already had aftermarket 16"'s fitted all round so ive never had the problem of finding 15" tyres in the right speed rating .

[Chris71]

What profile do you run after switching to 16" wheels? According to an online calculator I found you're only 6mm (IIRC) out on rolling radius if you switch down to a 50% profile. i.e. 205 50 R16 as opposed to 205 55 R15.

I guess you might not want to stiffen up the sidewalls on the front end and leave the rears on the [more flexible] 55% profile though? That might have enough impact on the overall stiffness to induce some understeer.

[BeastMaster]

Just to add my 2d worth

If running different speed ratings please notify your insurance and get a note - also remember that the speed rating is not just for the max speed but are reinforced to cope with power delivery of performance cars.

When voting for standard wheels and tyres, is this standard size tyres to the year of manufacture as the profiles changed eg 205/60ZR15 to 205/55ZR15 to 205/50ZR15 depending on year. I have stuck to the orignal on the rear of 225/55ZR16 although in 1995 they changed to 225/50ZR16 because it may change the gearing and speedo reading.

I now need to get the fronts changed so am thinking that I can choose any of the options from the above sizes to find a tyre to match the rears which are Uniroyal Rainsport 2 the only consideration being ride height.

As a footnote - my car has power steering and as such could cope with the wider front option, and was uprated to a 500 by the factory in 1999 but the tyres have not changed. I have decided to keep the narrower sizes as the car is very planted and balanced, something that may be upset if going wider - breakaway more sudden, and the dreaded aquaplaning when wet.

Andy

Andy

[Grey Ghost]

rigga said:

17" all round with Falken 452 rubber

Same here. Very nice tyres for the money.

[Johno]

225/45/16's

245/45/16's

Toyo T1-R's

Griffith 500SE

Edited by Johno on Monday 22 November 14:34

[Chris71]

BeastMaster said:

As a footnote - my car has power steering and as such could cope with the wider front option, and was uprated to a 500 by the factory in 1999 but the tyres have not changed. I have decided to keep the narrower sizes as the car is very planted and balanced, something that may be upset if going wider - breakaway more sudden, and the dreaded aquaplaning when wet.

This is the main thing on my mind. Mine doesn't have PAS and the 225 width tyres on 18" wheels make it feel like a bit of a truck. It robs the steering of much of its subtlety and at slow speed I even wonder if you'd be able to wind on corrective lock quick enough - it's a long way from the 'flick of the wrist' action on the Caterham. There again, that only weighed 508kg.

Should point out I have driven several non-PAS on standard tyres and owned a non-PAS S3, so I'm not just being a big girl. Honest.

Likewise, I'm not particularly worried about outright grip (within reason) if I can trade some of it for consistency, feedback and progressive breakaway.

[.Mark]

Chris71 said:

Are they standard size tyres running on the regular 15" front / 16" rear wheels?

They are the bog standard TVR fit alloys, so yes, standard tyre sizes, as for actual sizes I can only say I have replaced like-for-like size since I got her so can only assume it's as she came out the factory.

If it helps I can get the sizes for you when I am home this evening, can't remember off the top of my head because I have just replaced the Cerbera tyres and so only have those sizes running round my head - I can't internally store too much data

[DavidLScott]

Chimaera 450 on standard proper rated tyres.

Fronts: Dunlop SP9000 but not sure if they are available any more.
Rear: Falken 452 because I couldn't get the matching Dunlop SP9000's a eyar afetr getiing the fronts done.

Suit me fine but I don't go rushing around in the wet so cant comment one way or the other.

[spend]

Johno said:

225/45/16's

245/45/16's

Toyo T1-R's

Griffith 500SE

Edited by Johno on Monday 22 November 14:34

I got those sizes (albeit the superior TVR T1-S's ) with the factory spider/brake kit on a 93 car & the speedo is perfectly fine.

[Chris71]

.Mark said:

If it helps I can get the sizes for you when I am home this evening, can't remember off the top of my head because I have just replaced the Cerbera tyres and so only have those sizes running round my head - I can't internally store too much data

I'd love to have two TVRs to confuse. I'm really quite jealous.

Back to wheels, what type of wheels did the Griff SEs run? ...interesting to see people using 45 section tyres on the 16" wheels; that must put the rolling radius at least as low as the 55s on the regular 15s?

[edward1]

Sp9000's on the front and Goodyear Eagle (no longer available) on the rear. I initially didn't like the sp9000's as I was suffering understeer that wasn't there in the past, however the correct geometry set up sorted that problem and I have been pretty happy since.

[Chris71]

Sorry, I'm sure I've asked this elsewhere, but I can't find it: What width wheels are people using - are they 7" all round?

I've noticed that Pro Race 1.2s for example (switching to wheels now!) are only available in 7" width for 16" diameter.

[Johno]

spend said:

Johno said:

225/45/16's

245/45/16's

Toyo T1-R's

Griffith 500SE

I got those sizes (albeit the superior TVR T1-S's ) with the factory spider/brake kit on a 93 car & the speedo is perfectly fine.

On the basis the T1S was replaced with the T1R (seems wrong way round I grant you), I contest your claim of superiority of your S's versus my R's (in fairness having been through at least 2 sets of both the difference wasn't apparent to me and as you know, I do a fair number of miles in all conditions and really there wasn't anything I noticed . ..

Edited by Johno on Monday 22 November 18:15

[.Mark]

edward1 said:

Sp9000's on the front .... I initially didn't like the sp9000's as I was suffering understeer that wasn't there in the past, however the correct geometry set up sorted that problem and I have been pretty happy since.

Interesting, I experienced the same as you, since had Gaz Gold Pro's fitted and a geometry setup and the understeer has indeed become less obvious. I'm still not keen on the 9000's as before with the Bridgestones the steering was so direct.
Bridgestone now do a new S001 (got them on my company car and they feel good), if I can ever wear down the 9000's and if B'stone do the S001 in TVR size I'm going to give them a go.

[S3DaveP]

I recently got my Griff 500 and it was fitted with std size ZR rated bridgestone Z02 on the rear and Z03 on the front. the fronts were worn close the the limit, so i replaced them with some Yokohama A022's 225/50/R15 91V as i could not find anything other that budget tyres in the correct ZR rating locally or on the internet.
I spoke to my insurance company and they were Ok with the lower speed rating.
The handling seems fine with these tyres, less tramlining than the S03's, but this maybe because they are new.

Dave

[Chimpafrolic]

Hi Chris I run Goodyear Eagle F1 directionals all round.

• Fronts: 205/50 ZR16 87Y

This size may be considered a bit skinny by some.

However in my opinion the 205's give lovely steering feel (I have power steering) without excessive understeer, I drive briskly on the road but have never taken the car on a track.

• Rears: 225/50 ZR16 92Y

The Y rating means all the tyres are approved for speeds of up to up to 186 mph.

Eagles give excellent grip in the dry a shed water brilliantly which is essential in a TVR if you ever get caught in a downpour.


Here is how 15" front wheels compare with 16" front wheels with my tyre choice.

Standard 15” Front wheels
Tyre width: 205mm
Aspect ratio: 55
Tyre wall height: 112.75mm
Final rolling dia: 493.75mm

16” Front wheels
Tyre width: 205mm
Aspect ratio: 50
Tyre wall height: 102.5mm
Final rolling dia: 508.9mm

In summary:

* The contact patch exactly the same as the standard setup

* Final rolling dia is increased by 15.15mm

* Tyre wall height is reduced by 10.25mm

The additional rolling dia only serves to lift the front of the car slightly.

I have a full set of the latest Gaz Gold Pro adjustable dampers so its a simple case of lowering the front ride height by 15.15mm to bring the front end ride height back to exactly where it was with the standard 15" front wheels.

The sidewall height has been reduced by almost 10%, which in theory should give a tyre wall that's 10% stiffer and therefore 10% more resistant to cornering deformation.

I would say its a nice compromise between improving the sidewall deformation without compromising ride quality.

In my humble opinion fitting very low profile tyres on bigger after market wheels often leads to a really harsh crashing ride on Chims & Griffs that's just not nice at all.

So the benefits of moving to 16" front wheels are:

1) Improved availability of quality front tyres at a decent speed rating

2) A stiffer tyre with less sidewall deformation during cornering

3) Retention of ride comfort

4) Original look of the standard wheels is retained

5) Should work out a lot cheaper than buying a full set of after market wheels and the inevitable four new tyres to go with them

Definitely a worthwhile mod.