I'm just about to fit a set of aftermarket alloys to my MK7 Golf GTD. The wheels are Rotiform IND-T in Silver/Machined and the specs of them are 18x8.5 ET45. Tyres are Michelin Pilot Sport 4 in 225/40-18. These wheels use a radius bolt seat, the same as the OEM wheels.
I'm trying to figure out if I need longer wheel bolts and if so how much longer. The OEM bolts (27mm thread length) when fitted to the OEM Nogaro wheels protrude from the mounting face of the wheel on the inside by 19mm.
When these bolts are fitted to the Rotiform wheels they protrude by 16mm so with a 3mm difference one would say I need bolts with a 30mm thread length to match the amount of thread available on the OEM set up but... having done a good bit of research the minimum amount of rotations that is recommended for a 14x1.5 wheel bolt (stock bolt for VW) is a 7.5 turns. So I checked this with my OEM wheels and I only get 6.5 turns from initial thread engagement to fully tightened at 120NM. With the Rotiform wheels I only get 5 turns. So neither are 7.5 or above, not even the OEM setup??
Can anyone advise here?
I did contact Rotiform directly and they gave me an a totally useless answer - they said I should be O.K. using the OEM bolts but if I had any concerns with the amount of thread engagement I could buy longer ones. Great info
I'd like to be a bit more solid than "should be O.K." when it comes to attaching wheels to my car to be honest and I can buy longer bolts? Thanks for the the tip... I would have thought that the manufacturer would be able to confirm on what is required.
I also contacted three Rotiform dealers for advice by email and not one replied. Nice.
Thanks.