18" Alloys Wheels

Sep 18, 2009
2,443
1
Shropshire
Could i get away away with running 18" alloys with 205/45/R18 Alloys on standard suspension and springs on a mK1 Leon FR TDI ?

Also what offset would i be needing ?
 

dholdi

Active Member
Jul 3, 2008
931
4
Preston
You want 225/40/18 tyres to maintain the aspect ratio although without getting the calc out the tyres size you mention would also be close, but why go narrower ?
 

FSiLeonMike

Barmy Army Reservist (TA)
Apr 26, 2007
1,303
0
Bury St Edmunds/Stowmarket-ish
You want 225/40/18 tyres to maintain the aspect ratio although without getting the calc out the tyres size you mention would also be close, but why go narrower ?

Only advantage to this would be a very slight improvement in fuel consumption and straight line speed.

Back in the early 90's, Tyrell F1 used to qualify with front whhels all round on their car, the straight line speed was much better, they did this until the powers that be decided it was "un sporting"

Also, with less off a contact area on the road, and a lower unsprung weight, accelleration, in theory, is quicker.

But all this gain is at the expense of grip. So yes, why go narrower? You'll just go into the ditch faster
 
Sep 18, 2009
2,443
1
Shropshire
I dont have to use the tyres i mentioned i can go with 225/40/18. Iam looking for a set of 18's without tyres so i have my own option of tyre brand. I have plenty of space in the arches but the suspension strut is looking close to the top of the tyre.

What PCD and ET offset are used on the MK1 Leons. Is anyone else using a different ET and spacers ?
 
Sep 18, 2009
2,443
1
Shropshire
5X100 ET35

An 18 on standard suspension will look like a monster truck IMO :)

Thanks mate.

if have more alloy and less tyre then the overall size should be the same as my 17's. The problem i have with dropping it is, this is my work car that i do loads of miles in, having a stiff bumpy ride with harder wear on bushes and tyres isnt going to make it very economical for me or my 600 miles a week journeys.

I take it the Cupra R springs are lower and stiffer then my FR ones but wont be as stiff as aftermarket springs. Will they fit my FR shocks ?
 
Last edited:

adam cupra 20vt

Built Not Bought.
Mar 31, 2005
6,162
2
Mud Hut
I replaced my standard 16's with 18's and with a 225/40/18 there were the same overall diameter

I would say with a 225/40/18 you should be the same overall as ypur 17's

Loads of room under the arches if you don't go silly wide, especially if its not lowered.

I think the R springs lower a cupra/FR about 10mm

You can buy JOM 40mm kits with shocks and springs for £130 shocks and springs are usually a nice ride.
 

sheffboy

avoiding potholes
May 25, 2007
655
1
et 45 is too high mate. your front wheels would rub the front struts.

If your wanting a comfy ride like you say I'd stick with 17s.
 
Sep 18, 2009
2,443
1
Shropshire
Bill Badger5 Forum sponsor.

If there aftermarket they will prob be tapered and not radius like the OEM wheels.

Don't forget longer locking bolts.

ok thanks.

Yer aftermarket. Went for a set of 18" Kahn RS-R.


prod_kahn_rs-r_080816120619.jpg
 

EmDee

Omnishambolic
If you can get six full turns of the bolts then you don't need longer ones. this will ensure it goes in as deep as it is tall and willl give the maximum strength/security. try the std ones and if you get 6 turns keep them ;)
 

adam cupra 20vt

Built Not Bought.
Mar 31, 2005
6,162
2
Mud Hut
ok, using a 10mm spacer it looks like then i'll be needing a 12mmx1.5 tapered wheel bolt with a thread of about 40mm.

No I'm pretty sure there 14 x 1.5 thread.

And unless you already have a set of tapered bolts you'd need new ones as OEM are radius head.

I'd also be very surprised if you got 6 full turns using a 10mm spacer with standard length bolts :)
 

FSiLeonMike

Barmy Army Reservist (TA)
Apr 26, 2007
1,303
0
Bury St Edmunds/Stowmarket-ish
My spacers are a pair of Delta Mics, which are supplied with 10 x Radius Bolts, and 10 x Radius Nuts, only prob with these is they are 50 quid a set, OK for the back, but on the front, I know DannyC87 experianced a little judder. He still managed a track day using them though. Talk to whoever is supplying the spacers, they will sort you out, and against the cost of a set of wheel/tyres and spacers, new bolts cost peanuts
 
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