New Wheels maybe 16" Tyres Etc

bonnietiler · Postby **bonnietiler** » 11 Feb 2014 14:16

I have a TR7V8 which i'm really pleased with, I have had to use it throughout the Winter as a commuter, always starts and stops (thanks to the MGRV8 genuine Brake pads/princess calipers) The tyres are fine (damned with faint praise of course) In that they are one of very few tyres actually available for the 13" minilite currently fitted, I have trawled the search engine but found some conflicting answers. Clearly, the most economical method is MGF wheels either 15 or 16 inch. I sort of lean to 16" in the event that I want to go for larger discs in the future should I breath on the motor at a future date?
Could anybody advise me on fitment of either size with tyre size used and the need if any for bodywork mods due to the increased dimensions. Are they a direct fit, do I need to modify hubs in any way are the wheelnut dimensions the same?Will this impact on speedo readings? I am using Power assisted steering so doubt that the feel and weight will be effected unduly

alc59 · Postby **alc59** » 11 Feb 2014 16:40

I can't answer your questions, but I can offer some gold 13 inch minillites a good home.
Best wishes
Al

HowardB · Postby **HowardB** » 11 Feb 2014 19:24

I have older MGF 14" wheels on my 7 with 185's at the front and 205's at the rear. Fixing bolts are at the correct centers already, but the center hole needed to be v slightly opened out on one wheel only.

If I recall correctly there is a very slight difference in the overall dia but not enough to worry about - I use a GPS speedo as a back up anyway for accurate speed measurement.

I will post a picture later

Beans · Postby **Beans** » 11 Feb 2014 20:18

In my opinion ride will suffer with 16" wheels.

<center>

1976 TR7 FHC (needs some TLC ...)
1980 TR7 DHC (my first car, a.k.a. Kermette)
1981 TR7 FHC (Sprint engined a.k.a. 't Kreng
[url="http://www.tr7beans.blogspot.com/"]My full Blog[/url]</center>

Hasbeen · Postby **Hasbeen** » 11 Feb 2014 22:59

I'm with Beans.

I have a 7 with 13 X 6 wheels, shod with 185 70s front & 205 60s rear. This combination gives the best car I have ever driven on a long drive. I have done 1300 kilometers in a day, & enjoyed that night, out with friends.

I have a 4.6L 8 with 15 X 7" wheels, with 195 60s front, & 215 60s on the back. It is a really great car, with incredible overtaking ability, & handling, & a joy for about 400 kilometers. I have done the same 1300 kilometer drive in it, & would never do it again.

These cars need that big bag in the tyre as part of the suspension to make a good tourer. If you don't want to drive long distances, the 15s do allow those larger brakes, but even for the 16s on my Honda S2000, the best performance tyres are no longer available, & I have just fitted some Kumho 13s on the 7, I am very impressed with. Apart for those big brakes, I can't see much advantage.

To answer your question, we had to roll the lip on both front & back guards to give adequate clearance, & that is with the very slightly wider Nissan Skyline diff fitted, replacing the standard one, which could not handle the 330 BHP.

Hasbeen

HowardB · Postby **HowardB** » 12 Feb 2014 01:51

Photo of car with MGF wheels

john 215 · Postby **john 215** » 12 Feb 2014 05:10

Hi,

As wheel diameter goes up the tyre profile tends to go down, with this the comfort level tends to reduce too, although handling can be improved. The speedo does not always change as the rolling diameter stay's approx. the same due to the profile drops.

I tried a set of 17" wheels on my mine once ( was given Avez's so thought " what the hell ?! " ) and they gave a very stiff ride due to 35 profile and just didn't like the look [V] Quite happy with 14" Revolutions now fitted.

Lots of options on this thread -

http://www.forum.triumphtr7.com/topic.a ... C_ID=12834

Cheers John

LIVE LIFE A QUARTER OF A MILE AT A TIME!

1976 Speke FHC Beauty Now with an overdrive conversion

1979 3.5 FHC(STATUS PENDING!!)

1982 2.0 DHC NOW A 4.6, BUILT NOT BROUGHT !!!!

Beans · Postby **Beans** » 12 Feb 2014 07:13

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Hasbeen

... I have a 7 with 13 X 6 wheels, shod with 185 70s front & 205 60s rear. <hr height="1" noshade id="quote"></blockquote id="quote">
Interesting. Since changing the wheels on my DHC from 5,5Jx13" to 6Jx13", while using the same 185/70 tyres, the car handles much better and is more precise.
Not as precise as the Sprint (on 7Jx15" with 205/50 tyres) but a very good allrounder indeed.
And certainly more comfortable, which is good for a long distance touring car.

<center>

1976 TR7 FHC (needs some TLC ...)
1980 TR7 DHC (my first car, a.k.a. Kermette)
1981 TR7 FHC (Sprint engined a.k.a. 't Kreng
[url="http://www.tr7beans.blogspot.com/"]My full Blog[/url]</center>

bonnietiler · Postby **bonnietiler** » 12 Feb 2014 09:10

So, if f'rinstance I went down the 15" route then would 195/60 be an appropriate tyre size?
I currently run 6J 13" Minilites with Nanking 205/60 tyres.
Thinking about it, they are certainly a wider section than std will that impact on Speedometer accuracy at all?

saabfast · Postby **saabfast** » 12 Feb 2014 11:10

The width will not make a difference but the height will. Obviously the height is affected by the aspect ratio to the width.
There are a number of size calculators on the net, ie
http://www.etyres.co.uk/tyre-size-calculator
Your current tyres compared with the standard 185/70 show a -2.21% difference in diameter which is acceptable in speedo effect terms. Using 15" 195/60 show +4.41% which is over the recommended +/- 3% acceptable variation.
Easiest way to check on the car is to use a sat nav and see how far out the speedo is so that you are aware and avoid the speed cameras.

Alan
Saab 9000 Stg 1 (now passed to son for his family car)
Saab 9000 2.3 FPT Auto (now gone that others might live)
Saab 9000 2.3 LPT Auto
Saab 9-5 2.3 Vector Auto Estate
'81 TR7 DHC

bonnietiler · Postby **bonnietiler** » 12 Feb 2014 12:00

Understood, so a 55 ratio would be preferable.
many thanks
brian

jeffremj · Postby **jeffremj** » 12 Feb 2014 15:57

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by bonnietiler

Understood, so a 55 ratio would be preferable.
many thanks
brian
<hr height="1" noshade id="quote"></blockquote id="quote">Correct. A simple method is this:

205/60x13, then 205/55x14 and 205/50x15 will give similar speedo values.

Or try 185/70x13, then 195/60x14 and finally 205/50x15 all have similar rolling radii.

I leave it to you to work out relevant 16" and 17" values.

HDRider · Postby **HDRider** » 12 Feb 2014 16:55

I have 15" wheels and 205/50/15 tires on my TR8 and am very happy with the tire performance. My lap times at Autocross have been consistantly lower since I made the change.

The power steering has no issues with the larger tires and no problems at all as far as body clearances go. Not to mention they look great on the car.

I would not want to go to a lower profile tire personally. Too stiff a ride and too easy to muck up the wheels on the crappty roads around here.

Edward Hamer
Petaluma CA

alc59 · Postby **alc59** » 21 Feb 2014 15:03

Still up for the minillites
Al

busheytrader · Postby **busheytrader** » 22 Feb 2014 08:23

I've tried 15" 50 profile (on white MG Maestro Turbo lattice alloys) and my personal rear end felt every bump and thump.

I prefer driving with the 14" 60 profile since the handling is almost identical as the 50 profile but the ride is more compliant.

(Same opinion as learned friend John)

Adam

TR7 V8 DHC Jaguar Solent Blue. 9.35cr Range Rover V8, Holley 390cfm, JWR Dual Port, 214 Cam, Lumention, Tubular Manifolds, S/S Single Pipe Exh, 3.08 Rear, 200lb Spax & PolyBushes all round, Anti- Dive, Strut-Top Roller Bearings, Capri Vented Discs & Calipers, Braided Hoses, 4 Speed Rear Cylinders, Uprated Master Cylinder & Servo, AT 14" 5 Spokes or Maestro Turbo 15" Alloys, Cruise Lights, S/S Heater Pipes, Replacement Fuel Tank. No Door Stickers. Mine since July 1986, V8 from 1991 courtesy of S&S V8 conversion and big brake kits.

Anonymous

New Wheels maybe 16" Tyres Etc

New Wheels maybe 16" Tyres Etc

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