DAYTONA Sports Car Upgrades/improvements

[spookypt]

Hi, well I'm finally getting to the car to measure up some new rims and tyres for it. The current rims and tyres are
Rear 295/30 18 on 18 x 10.5 +25mm OS/170mm backspace +4mm spacer
Front 265/35 18 on 18 x 10 +31mm OS/170mm backspace

The current set up sticks out 15mm from the rear guards and fouls the coilover without the spacer and the front scrub on full lock on the A arms.

So unlike cobras I want a taller or equal tyre profile in the rear. I need to stay with 18's due to my large brakes.

So far, I reckon I have the rears correct. They'll be 275/40 18 NTO1's 18 x 9.5with +28mm OS/161.35 backspace. They sit in under the guards at full compression and miss the coil overs internally at full droop.

The fronts are more of a question. (the fronts in the pic aren't exactly what I'm looking to do. They are 235/40 18 on 18 x 8.5) so a 245/40 will be taller and fuller looking but same essentially frontspace position.

I either go 245/40 on 18 x 8 or 275/35 on 18 x 9.5. Any thoughts or comments?

(The links below may help others work out their desired sizes if they're looking to fit new wheels.)
Current:

Proposed






NT01 D.O.T.-Compliant Competition Road Course Tire
Tyre Size Calculator
Online Wheel and Tyre Fitment Calculator. Offset, Tyre Stretch and Speedo Error | Will They Fit
Wheel Offset/Backspace Calculator - Calculate/Compare Wheel Offset and Backspace

I know Serpent (Theo) has mentioned he runs 18 x 9.5 with a 150mm backspace (+16.65mm offset) all round but there is no way that OS will clear my rear coil overs in teh rear and it'd protrude my front guards another 8mm more s just goes to show all cars are different.

So feedback on using an 8inch wide front or 9.5 would be appreciated. I've got planet of spare race rims for the car so essentially is road and drive to sprints fun as well as making the car look a little more correctish.

(Thanks Pete H and Towy for the lone of their wheels)
Spookypt