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new wheels on but got a problem>>>&

right i got my new fox 4 evos on my car with 195/45/15 tyres on (i had 185/60/13 before) the ratio is 0.8% diff in size, before i was able to ge the car to 100mph befor ei ran out of road not it sits at 90 in forth and wont go any more it sits quite hapily at 5000 rpm and ive still got another gear whats going on, my cat is f***ed so im getting more mid torque is this substituted high end torque or what could it be the diff in weight of the new wheels.

im stuck.

help please.

cheers jamie.

60% of 185 = 111mm(4.44") + 13" = 17.44"
45% of 195 = 87.75(3.51") + 15" = 18.51"

Thats roughly the differance, quite alot.

bigger wheels doesnt mean higher top end at all!

Your gearing/engine was designed to top out in top gear with a rolling radius of 17.44"

You have know lost your rolling radius and in turn lost your engines ability to top out in top. so to speak.

sh* what do i do to get it back.

or to improve on it...lighten the car...

im getting nitrous fitted in two weeks.
  Skoda Fabia vRS

i think the nitrous should do it hehe

after i fitted my 15s i got my RT chipped at Hill Power an it was transformed after that !

really m8 because the engine is wicked it blows away many a nova sr and ax gts etc etc. but i want more top end so will the no2 sort out my top end problem.

i dont know what to suggest, other than rectifying the problem, sorry.

I havnt the technical knowledge to advise you what power(torque) your engine needs to develope to overcome the gearing losses.

maybe your get lucky and the captn may comment!

i hope so if not ill just get an engine conversion to a 16 megane or something then add the no2.

any one else (captin you here)

cheers jamie.

Hi Jamie.

If yer cat is f*(KED, then it may well be effecting overall power..

what makes you think you have more torque mid range with a knackered cat m8 ??.

by putting on bigger wheels you are applying a larger turning force to the power unit.. there will be a max torque figure that you cannot overcome.. on the 1.4, perhaps you have hit it already. ??

2 ltr me thinks lol