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Old 01-17-08, 04:26 PM   #1 (permalink)
Roary
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345/35x15 too wide?

On the KVA I aquired in December there are a set of 345/35x15 tyres on the rear fixed to revolution wheels. Having researched what many other users have on their cars I feel a bit unusual and am now wondering about the rear section that I have and the usability of such wide tyres.

I have managed to find replacements OK but would appreciate any feedback from anyone using 345 tyres.

Many thanks

Chris
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Old 01-17-08, 04:40 PM   #2 (permalink)
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Re: 345/35x15 too wide?

Chris,

345's are huge bites in the pavement! Can you post a picture of the rear of your car that shows the body work on the car, looking up the tailpipes so to speak?

I would be interested to see what the rear clip looks like from the rear, and how the tires fit up under the flares.

Thanks in advance for your efforts!
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Old 01-17-08, 05:01 PM   #3 (permalink)
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Re: 345/35x15 too wide?

The only picture I have is when I draped the body over temporarily before it was strapped to the roof of the garage whilst I work on the car.

It does not give much away as to the suitability but time will tell I guess...
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Old 01-17-08, 05:20 PM   #4 (permalink)
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Re: 345/35x15 too wide?

Nice a**
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Old 01-17-08, 08:38 PM   #5 (permalink)
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Re: 345/35x15 too wide?

Chris,

Your photo shows a little bit of the footprint those huge tires are making. Thank you for taking the time to post that shot for me.

Keep going with your great work. Those rear tires are awsome! Wow.
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Old 01-17-08, 08:51 PM   #6 (permalink)
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Re: 345/35x15 too wide?

What make/brand tires are they?
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Old 01-17-08, 10:02 PM   #7 (permalink)
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Re: 345/35x15 too wide?

Hi,I have 335/30x18 on mine.Only issue is road noise on certain surfaces.

Cheers.
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Old 01-17-08, 11:33 PM   #8 (permalink)
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Re: 345/35x15 too wide?

Hoppy,

Do you have any issues with your clutch with those big tires?

PS: What is that yellow pickup like vehicle in your last picture? Looks like it has a Mustang frontend on it, with a pickup box(????).

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Old 01-17-08, 11:43 PM   #9 (permalink)
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Re: 345/35x15 too wide?

Looks like a Ford F6 Tornado "ute". Basically, it's the Aus version (smaller and less comfy) of an F150 Lightning Pickup.
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Old 01-18-08, 12:25 AM   #10 (permalink)
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Re: 345/35x15 too wide?

Chris
I currently have Avons mounted on 15 X 14" wide wheels and I personally think thats a nice look with the bodywork.
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Old 01-18-08, 01:35 AM   #11 (permalink)
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Re: 345/35x15 too wide?

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Originally Posted by Gary Kadrmas View Post
Hoppy,

Do you have any issues with your clutch with those big tires?

PS: What is that yellow pickup like vehicle in your last picture? Looks like it has a Mustang frontend on it, with a pickup box(????).

Gary,

PR at GT40 Australia uses 335s and his clutch is over 2 years old and he competes regularly.

The yellow car in the background is PRs 2006 Ford Falcon ute.
We still produce Falcons in OZ,a ute is basically a sedan from the b pillar forward and a pick up at the rear.You can get all the luxury (leather etc) in a work vehicle that will fit in a shopping centre car park.
5.4 lt(260 kw) with 6 speeds.

Mark,

The Tornado is a turbocharged multi port six.

Hoppy
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Old 01-18-08, 02:57 AM   #12 (permalink)
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Re: 345/35x15 too wide?

The 345/35-15 was OEM on two cars--the Lamborghini Countach and the De Tomaso Pantera GT5 and GT5-S. In the latter case, the tire was fitted on 15x13 wheels.

It is probably a perfect fit for a wide-body (Gulf flares) GT40 as well. You will probably have to tune the chassis to prevent terminal understeer if you are running 15x8 (or so) front wheels. The Countach used 225/50-15 fronts, and the Pantera used 285/40-15 (MUCH wider, and no longer available through conventional sources). Think big honking rear swaybar to get the rear end to rotate properly so you don't just plow straight off into the hedges.

I don't know what you would want to run on the front of a GT40 with 345/35-15 rear tires. You'd have to have something with a fairly low profile, as your rear tires are only 24 inches high. Looking at a representative 225/50-15, I see that it's listed as 23.9 inches which would make it a good match, height-wise. Unfortunately, you can't get much wider than that without getting substantially taller. Only Dunlop makes a 245/50-15, and that's 24.7 inches tall. Sports cars look decidedly weird when the front tires are taller than the rears.
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Old 01-18-08, 10:16 AM   #13 (permalink)
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Re: 345/35x15 too wide?

Thanks Mike, great information but now I am really confused...the tyres that are on the car will have to come off anyway as they will not pass the SVA test we have in the UK. (we have to have a "E" mark and these tyres don't have them.

As time goes on I can see the wheels coming off and me taking them to a specialist who works with historic tyres. Perhaps they can match me with a suitable front & back set.
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Old 01-18-08, 10:53 AM   #14 (permalink)
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Re: 345/35x15 too wide?

Well, you have several options if you are willing to sacrifice having pure 'road' tires.

Pirelli makes a 345/35-15 in their awesome P-Zero formula; is that what you currently have? Availability of those tires goes up and down, as they are produced in small batches, and they usually run out and are unavailable for a few months or a year before they fire up and produce another batch. Pirelli is also quite proud of them, reflected in their astronomical price of $502 each in the USA!

(The link below is a mile long, although this forum software renames it 'using cookies'; hopefully it will work for you, but if not, go to The Tire Rack - Your performance experts for tires and wheels and do a search on tire size, 345/35-15)

Using Cookies

These are fully street-legal tires. Given that they are produced in Italy I would *assume* that they have the requisite stampings on the sidewall. If they don't, I would recommend that you find a reasonable MOT tester and point out that although they are missing some trivial markings, they are of the utmost quality and that shouldn't stand in between you and a tax disc.

Failing that, then another potential solution is the Michelin TB-15 road/race tires. These are basically brand-new 40-year-old tires, i.e. they have brought back a 1960s racing design and made them fully road-legal, with a "V" speed rating. They are available in the UK from Longstone Tyres, and they are *bloody expensive*!!!! But besides looking right, they probably offer excellent traction (at the expense of lifespan)

http://www.longstonetyres.co.uk/Special_Offer.php

Here is some more information on these tires from the manufacturer website:

Michelin Sport - Set the page name

Note that the same sizes are available in the TB5 compound for use in temps above 20 C; not really a factor for a road tire in England!

I believe Avon Tyres also makes a tire that might be appropriate, although I don't think their rear tire sizes are quite as large as the ones above. But maybe you could live with them?

Personally, if you have tread remaining on your existing 345/35-15 tires (are they Pirellis, or Yokohama AVS?), I'd just run with those for the time being. Again, a few cases of beer on the passenger seat might be just the ticket to get them through the MOT inspection. And if you're anywhere near Leicestershire, I have a friend who owns an MOT station, and under special circumstances like this, can be seen inspecting his cars with the help of a guide dog and a cane, if you get my drift....
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Old 01-18-08, 11:08 AM   #15 (permalink)
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Re: 345/35x15 too wide?

Chris,

I run 345/35x17 Pirrelli P Z zeros rears on my GTD experienced no problems with clutch (full size mustang clutch with billet flywheel) In fact during car rebuild last spring i put the original clutch back in (11000 miles use)

In the renault R21 box heavy wear on CWP and differential, so replaced with ATB via Chris Cole. Also heavy wear on CV joints but these were found to be cheap repro's, replaced with genuine ford scorpio units.
Results of the above were a very quiet transmission and ride.

Front tyre size 235/45x17 runs okay with these but i have purchased 245/45x17, as I feel an improvement could be made to the general balance of the car.

regards,
John
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Old 01-18-08, 12:10 PM   #16 (permalink)
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Re: 345/35x15 too wide?

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Originally Posted by John Oxborough View Post
Chris,

I run 345/35x17 Pirrelli P Z zeros rears on my GTD...
I'll bet you a pint at the pub that you don't!

This, because nobody (including Pirelli) made a 345/35-17. They're all 335/35-17 (or 315/35-17).

But your general point is still quite valid--rear tire size won't play nearly as much a role in premature clutch/drivetrain wear as will excessive horsepower, driver technique, poor quality components (such as little girly Renault gearboxes and spindly driveshafts), etc. and so forth.

Back to the original issue, of running 345/35-15 tires. I forgot to mention that because these tires (and the matching fronts) are so short, the car will be noticeably lower that most other GT40s, which makes them look meaner, but the reduced ground clearance can be problematic on a car with precious little clearance to begin with. Even greater circumspection will be called for when dealing with speed humps, unkind garage forecourts, ferry ramps, etc.
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Old 01-19-08, 04:07 PM   #17 (permalink)
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Re: 345/35x15 too wide?

What timing. Apropos of this very discussion, a good friend of mine, an American living in northern Spain named Charlie McCall, just took his 1985 GT5-S Pantera out for a drive today. His wife shot some video of him easily roasting his 345/35-15 PZero tires.

High-res version here:

http://members.aol.com/PanteraGT5S19...eraHighRes.wmv

Low-res version here:

http://members.aol.com/PanteraGT5S19...teraLowRes.wmv

Regular attendees at Le Mans might recognize this car, as he makes the pilgrimmage every year.

P.S. I have found that clicking the links doesn't always work for some reason; right-click to download the file onto your hard drive, which then works every time.
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