The Wheels

In 2000 I replaced the wheels with Raceline RL-7 items similar to those fitted at the time to the Cerbera 4.5 and early Tuscans. I chose Raceline as I wanted to keep a TVR look to the car. The Griffith has 15” front and 16” rear wheels and after some deliberation I went for 17” fronts and 18” rears to retain the nose down stance of the Griffith, I think it works. At one moment I considered going for 16" and 17" but then I thought "In for a penny in for a pound."

Replacing wheels seems commonplace with owners these days so there is plenty of information available and dealers offering conversions but a couple of years ago it was pretty much trial and error. The first thing to check is the rolling radius of the new tyre size, if you stick to the same radius you “should” avoid issues with wheel arch clearance and speedometer error. Steve Heath has a useful tyre size calculator on his web site, look in the FAQ section http://ourworld.compuserve.com/homepages/shpub/ .

The next thing of to check is that the brand of tyre you select is available in the size you want, not always the case! I stuck to Bridgestone SO2 Pole Positions and as I do not have PAS chose 215 40 x 17 for the fronts and 255 35 x 18 at the rear. I would have gone for a 245 rear but they were not available in 18” from the Bridgestone, Toyo do offer the Proxes in a 245 35x18 so I may try these next time.

The Griffith wheels have a 4-stud 108mm p.c.d. (Pitch circle diameter) fitting, which is a Ford pattern, so doesn't represent a problem, however the issue is to establish the correct offset, not as easy as it may sound! I called Portfield who told me 35mm all round, just to double-check I called the factory and they confirmed this, they were however both wrong and this caused a few issues later. My advice would be to remove a front and rear wheel from the car and measure it, I did this afterwards and the fronts were 25mm and the rears 37.5mm. Incidentally the inside of my rims were marked 25mm on the front and 35mm on the rears, strange eh?

I chose 8” width rims and (erroneously thanks to TVR) went for a 40mm offset front and rear, in the end I wound up with 6mm spacers at the front to stop the wheels rubbing on the lower wishbones and 3mm spacers at the rear. A common question is, how does it handle with wider tyres & bigger rims, well to be honest I really don't think the ride is compromised and the steering feels slightly lighter if anything.

Finally I thought I’d be clever and get four alloy wheel centre caps from TVR to finish off the new wheels. They duly arrived but didn’t fit, seems the Cerbera has a 50mm centre bore to it’s wheels whereas the Griffith has 45mm so the caps were 5mm too large in diameter! Not to be deterred I sliced the backs off my new TVR caps, cut the flanges from the blue anodised jobs supplied by Raceline, Araldited them in place and bobs-your-uncle they fitted. I put a dab of silicone sealant on the back to save me losing them, stuck on the TVR centre badges and job done! It’s all rather complicated but it works, looks good and makes room for my 315mm brake discs.

Inside rim of standard rear wheel showing the marking ET35 (the offset in mm) and 7¹/₂J16H2 (width and diameter)