More questions .. tyres now :)

[stuntman]

Hello one and all.

My next question is ...

I have just purchased a set of 265/75/R16 Grizzles for moi truck.

I have a 40mm body lift on the old girl and I was wondering, will I need to trim anything on the arches, I will be doing the 'camel cut' but do I need to do any more?

Eventually I will be putting a 2" suspension lift on aswell.

PS what size in height are tyres if anyone knows off hand?

Cheers

Andi K

[stuntman]

Also, how much of a speed difference will it make from standard, probably badly worded here, what I mean is how much difference will there be in the indicated speed on the speedo?

Thanks in advance

Andi K

[mentalmoshio sophs V8i]

265/75/16 are 31,6 inch tall and gives an increase in speed of about 9 percent

[andygod]

I used to have 235 / 85/ 16 tyres and above 60 mph the Speedo read about 5 - 10 mph above the real speed. I now have 265 / 75/ 16 tyres and the Speedo seems pretty accurate at all speeds. I check the speed difference using a G.P.S unit so I get an accurate reading. I hope you realise that vehicle will be a lot slower with larger tyres than it was with the standard boots on.

[stuntman]

Yeah mate, speed isn't something I'm looking for in the truck.

If I was I wouldn't have sold my drift car! I will need to sort out the loan of a decent gps system to check the speed of the old girl.

[Range Rover Blues]

You can also do it on the motorway.  On the hard shoulder you'll see white sticks every 1/10th of a mile.  Provided they are accurate 9almost always) then you can time yourselfover a measured distance.

[hairyasswelder]

Yeah mate, speed isn't something I'm looking for in the truck.

If I was I wouldn't have sold my drift car! I will need to sort out the loan of a decent gps system to check the speed of the old girl.

You can borrow my road angel classic if you need one  ;)

[Charlie716]

All UK motorways are metric (little known fact) so the markers are at 100m not 1/10 mile [-X

[Range Rover Blues]

You can also do it on the motorway.  On the hard shoulder you'll see white sticks every 1/10th of a mile.  Provided they are accurate (almost always) then you can time yourselfover a measured distance.

[stuntman]

Excellent responses everyone, thanks.

Hairyasswelder I WILL eventually get to a meet, I just have such a hectic livestyle it's hard to commit to being anywhere!

[auf_wiedersehen_pet]

I used to have 235 / 85/ 16 tyres and above 60 mph the Speedo read about 5 - 10 mph above the real speed. I now have 265 / 75/ 16 tyres and the Speedo seems pretty accurate at all speeds. I check the speed difference using a G.P.S unit so I get an accurate reading. I hope you realise that vehicle will be a lot slower with larger tyres than it was with the standard boots on.

235/85s are 31.7" tall and do 637 revolutions per mile.
265/75 are 31.6" tall and do 636 revolutions per mile.

There should be no noticeable difference in "Indicated" speed, or for that matter "Real Speed".

Speedos are always optimistic and read too high. With my larger 235/85s, the indicated speed is reduced, however, this reduction brings it in line with the real speed. When checked against GPS, my speedo is no spot on throughout the scale.

This might be useful...

http://www.miata.net/garage/tirecalc.html