Wheel and tyre weights and bhp/tonne

[neilg]

Hi chaps, for those who are interested

 

Just changing my wheels from SLR rims with Toyo R888s to MBs with Michelin slicks ( for Cadwell trackday) and i thought i'd weigh them just to compare. ( time on my hands this evening )

 

1. 8inch SLR with 205/60-13 Toyo R888 is 14.1kg 😳 ( 85% worn)

2. 6inch SLR with 185/60-13 Toyo R888 is 11.9 kg

3. 8.5inch MB with 20/54-13 Michelin slick radial is 9.9kg 🥰

4. 6.5 inch MB with 16/53-13 Michelin slick radial is 9.2kg 🥰 🥰

 

So 52kg against 38.2kg. A saving of 13.8kg. Blimey No wonder they cost so much !

 

Just for comparison i weighed my Minilights with Yoko A021Rs and they weigh

 

1. 6 inch minilight with 205/60-13 A021R is 12.5kg ( 80% worn)

2. 6 inch minilight with 185/60-13 A021R is 12.2kg

 

While i was being anal i also removed my fire extinguisher which was 3.9 kg and weighed my nose cone ( fibre glass) with number plate at 3.4kg

 

In terms of power to weight then i know from a piccy of my car on proper scales with full tank of fuel and SLR rims that it weighs 465 kg.

With slicks then and MB's it weighs 451 kg.

 

Assuming i have about 185 bhp( tuned Honda Blackbird 1.2) this gives a power to weight of 397 bhp/tonne and 410 bhp /tonne repectively when brimmed with fuel.

 

I am 87 kg ( ) so then this falls to 335 bhp/t and 343bhp/t when i'm in it.

 

I suppose with carbon nose cone and rear wings i could shave off another 5kg??

 

Anyway anal mode off-

Cheers Neil

 

 

 

 

 

 

 

 

[6speedmanual]

As well as the saving in dead weight, you will also have made massive reductions in the power needed to accelerate 4 large "flywheels". You should feel significantly more spritely performance.

 

Enjoy!

 

Peter

[anthonym]

copied op to fix the damaged formatting - with my thanks to neilg from 2011 :-)

Hi chaps, for those who are interested

Just changing my wheels from SLR rims with Toyo R888s to MBs with Michelin slicks ( for Cadwell trackday) and i thought i'd weigh them just to compare. ( time on my hands this evening 

1. 8inch SLR with 205/60-13 Toyo R888 is 14.1kg  ( 85% worn)

2. 6inch SLR with 185/60-13 Toyo R888 is 11.9 kg

3. 8.5inch MB with 20/54-13 Michelin slick radial is 9.9kg 

4. 6.5 inch MB with 16/53-13 Michelin slick radial is 9.2kg 

So 52kg against 38.2kg.

A saving of 13.8kg. Blimey 

No wonder they cost so much !

Just for comparison i weighed my Minilights with Yoko A021Rs and they weigh

1. 6 inch minilight with 205/60-13 A021R is 12.5kg ( 80% worn)

2. 6 inch minilight with 185/60-13 A021R is 12.2kg

While i was being anal i also removed my fire extinguisher which was 3.9 kg and weighed my nose cone ( fibre glass) with number plate at 3.4kg  In terms of power to weight then i know from a piccy of my car on proper scales with full tank of fuel and SLR rims that it weighs 465 kg. With slicks then and MB's it weighs 451 kg. Assuming i have about 185 bhp( tuned Honda Blackbird 1.2) this gives a power to weight of 397 bhp/tonne and 410 bhp /tonne repectively when brimmed with fuel. I am 87 kg so then this falls to 335 bhp/t and 343bhp/t when i'm in it. I suppose with carbon nose cone and rear wings i could shave off another 5kg?? Anyway anal mode off- 

 Cheers Neil