Different Wheel Offset Driver/Passenger Side?

[dodds-gttdi]

I'm looking at replacing my alloys with another set in the next few month (so they'll be up for sale soon) but I needed to know if my new set of alloys would work (offset, tyre size, etc). So last night I went out and measured my current alloys and how much inset there was between the wheel outer rim and the top-most outer part of the arch.

I have OEM Seat BBS Alloys 18 x 7.5" ET 51 so pretty normal (same as GTI 18's) and 225/40/18 Toyo T1R tyres. My car is lowered on Eibach Pro Springs also

These are the results I got, wheel rim to arch:

Driver Front: 19mm
Driver Rear: 21mm
Passenger Front: 15mm
Passenger Rear: 19mm

 
I can remember somebody observing that the rear axle on a Mk4 golf was 10mm narrower (to counter understeer) so I assumed this was the same with the Mk5. Can anybody tell me what may be wrong with my car?

I haven't had it 4 wheel laser aligned after my lowering springs. Would that solve it?

Thanks in advance for your help/opinion.  

[sub39h]

Your measuring system will be far too inaccurate to pick up differences in mm

It would be worthwhile getting a 4 wheel alignment

[dodds-gttdi]

Your measuring system will be far too inaccurate to pick up differences in mm

  Have you read the first post? One wheel is majorly out! By 4 or 6 mm!! Plus there is no difference in axle width between front and rear. I thought the rear was 10mm narrower.

It would be worthwhile getting a 4 wheel alignment

This I thought. Anybody used CLCM Alignment in Sighthill, Edinburgh? Any good reports, price estimates?

[sub39h]

Your measuring system will be far too inaccurate to pick up differences in mm

  Have you read the first post? One wheel is majorly out! By 4 or 6 mm!! Plus there is no difference in axle width between front and rear. I thought the rear was 10mm narrower.

so your steering wheel was 100% bang on straight to within 1mm, you were on ground that has been proven to be perfectly level, you measured at exactly 0 degrees on the wheel on all 4 ocassions, there was absolutely no human error between you and your tape measure?

even if your wheel was bang on straight, which i assume it was, by your own admission you've had a suspension mod without having it aligned, so it's probably going to be out a little anyway.

sorry to sound obnoxious but i stand by my comments. you can't measure this accurately enough for 4  - 6mm to mean anything at all.