16 replies to this topic

[Tim F]

Hi all, Hope you can help me out I'm getting some speedline'a'likes but slightly different on the front 7.5 x 16 instead of 7 x 16. 1) Are the sizes below correct, is any preferable? Front 195/50/16 205/45/16 Rear 225/45/17 235/45/17 2) What speed rating? 3) What tires should I go for? I want a cheaper option full road tire that will sit on Gaz suspension. Not semi slicks. Thanks! Tim

[Retset]

195/50 R16 is the 'right' size - same as an Exige or VXR. Diameter 60.14 cm

205/50 R16 gives a slightly bigger rolling radius so fills the arch better. Extra width no problem for handling. Diameter 61.14 cm.

205/45 R16 gives a slightly smaller rolling radius so may look a bit small unless car well lowered. Diameter 59.09 cm.

Pic below is 205/50 R16 and very low (110mm ride height). Car being raised today as I am fed up of scraping it (second pic - also gives an idea of what a 205 looks like in the arch).

As for tyres - Kumho KU31 will do everything you want. The 205/50 R16 is more available and cheaper than the 195/50 R16

For rear, just keep standard 225/45 R17.

[Crazyfrog (Fab)]

Car being raised today as I am fed up of scraping it

did try that height and i agree far to low

[Tim F]

Thanks v much all

[Winstar]

195/50 R16 is the 'right' size - same as an Exige or VXR. Diameter 60.14 cm

205/50 R16 gives a slightly bigger rolling radius so fills the arch better. Extra width no problem for handling. Diameter 61.14 cm.

205/45 R16 gives a slightly smaller rolling radius so may look a bit small unless car well lowered. Diameter 59.09 cm.

Pic below is 205/50 R16 and very low (110mm ride height). Car being raised today as I am fed up of scraping it (second pic - also gives an idea of what a 205 looks like in the arch).

As for tyres - Kumho KU31 will do everything you want. The 205/50 R16 is more available and cheaper than the 195/50 R16

205/50 R16 will give the closest rolling radius to the 175/55 R17 of the original brigstones so the best option for the std ABS

[Darcini]

195/50 R16 is the 'right' size - same as an Exige or VXR. Diameter 60.14 cm

205/50 R16 gives a slightly bigger rolling radius so fills the arch better. Extra width no problem for handling. Diameter 61.14 cm.

205/45 R16 gives a slightly smaller rolling radius so may look a bit small unless car well lowered. Diameter 59.09 cm.

Pic below is 205/50 R16 and very low (110mm ride height). Car being raised today as I am fed up of scraping it (second pic - also gives an idea of what a 205 looks like in the arch).

As for tyres - Kumho KU31 will do everything you want. The 205/50 R16 is more available and cheaper than the 195/50 R16

205/50 R16 will give the closest rolling radius to the 175/55 R17 of the original brigstones so the best option for the std ABS

Would a 205/55 R16 go too far the other way? ie rolling radius greater than the optimum of the originals?

[Ouchie]

A massive 8mm larger diameter.

Tyre Size Calculator

[Darcini]

So 13mm smaller diameter is better than 8mm larger? And if so why? In tyre sizes of course

[Ouchie]

So 13mm smaller diameter is better than 8mm larger? And if so why?



In tyre sizes of course

23mm smaller is preferred, if you go for 195/50/16.

If it's good enough for a factory VXR and Elise then it's good enough for a VX. Maybe expect ABS issues.

I currently have KU31 205/45/16xl and no problems except a touch more arch gap than with larger diameter tyres. Meh.

Edited by Ouchie, 08 July 2009 - 07:01 PM.

[Ouchie]

For reference... Tread Width(mm)...Profile Height(%)...Wheel Diameter(inches)...Tyre Diameter(mm)...Difference(mm) 175...55...17...624...[N/A and Turbo] --- 195...50...17...627...+3 195...45...17...607...-17 195...40...17...588...-36 --- 205...55...16...632...+8 195...55...16...621...-3 205...50...16...611...-13 195...50...16...601...-23 [VXR, Exige, Elise] 205...45...16...591...-33 195...45...16...582...-42

Edited by Ouchie, 08 July 2009 - 07:16 PM.

[Darcini]

quote] If it's good enough for a factory VXR and Elise then it's good enough for a VX. [/quote] Wouldn't dispute that for a moment, even I could tell the difference when I fitted 16/17's to mine, albeit with T1R's! However what I don't understand is why a smaller diameter wheel on the front improves handling, (apart from the lighter unsprung weight, which would still apply if retaining the original 17" diameter but with a lighter wheel?)

[goodeg]

If it's good enough for a factory VXR and Elise then it's good enough for a VX. Maybe expect ABS issues.

Except the VXR, S2 Elise & Exige all have the 4 channel ABS rather than the 2 channel on the NA & VXT.

So would any of these:

205...55...16...632...+8
195...55...16...621...-3
205...50...16...611...-13

not be better than 195 50 16 given they are closer to the standard diameter.

I currently have standard wheels on my turbo but I am looking to change to TD's and trying to work out the best tyre sizes without introducing ABS problems.

[theolodian]

If it's good enough for a factory VXR and Elise then it's good enough for a VX. Maybe expect ABS issues.

Except the VXR, S2 Elise & Exige all have the 4 channel ABS rather than the 2 channel on the NA & VXT.

So would any of these:

205...55...16...632...+8
195...55...16...621...-3
205...50...16...611...-13

not be better than 195 50 16 given they are closer to the standard diameter.

I currently have standard wheels on my turbo but I am looking to change to TD's and trying to work out the best tyre sizes without introducing ABS problems.

I think that the issue there is finding tires actually made in some of these sizes.

[goodeg]

R888's & A048's are available in 205 55 16 T1R's & KU31's are available in 205 50 16 T1R's are available in 195 55 16 By available I mean listed on the Camskill website, I am unsure of stock.

Edited by goodeg, 08 July 2009 - 07:53 PM.

[theolodian]

R888's & A048's are available in 205 55 16
T1R's & KU31's are available in 205 50 16
T1R's are available in 195 55 16

By available I mean listed on the Camskill website, I am unsure of stock.

Oooh, and Nankangs!

Cor, those T1R's are a bit cheaper than the 175/55-17's! (which are listed as not available of course)

Has no one tried 195/55-16's?

[techieboy]

Cor, those T1R's are a bit cheaper than the 175/55-17's! (which are listed as not available of course)

Has no one tried 195/55-16's?

I'd guess taller sidewall profiles would be just about the last thing you want to do with T1R's. The 50 profile was squidgy enough and can't imagine it'll be any better with a 55 profile.

[Extrapilot]

However what I don't understand is why a smaller diameter wheel on the front improves handling, (apart from the lighter unsprung weight, which would still apply if retaining the original 17" diameter but with a lighter wheel?) The 16" wheel will re-distribute the weight, and make the car less likely to understeer. By changing the suspension, you get the option to lower the front, and put more downforce on the tyre. Hope that helps