Wheel clearance

[Merv and Sharon]

How far, if at all, can tyres/rims protrude from the body to pass inspection? I think I know the answer! Just checking.

Merv

[Beejay]

Merv,

Even if they could protrude past the body would you want them to?

Much better to have them tucked under and go lower!

Ben

[bret a ewing]

4 X 4 ?

[Merv and Sharon]

Missing the point guys. My new wheels seem to protrude about a cm beyond the wheel arch at the rear. Now do I have to get the arch extended, get new rear wheels or is there an allowance under Australian rules? Many Cobras are on the limit here but I seem, for some reason, to be just over it. Not sure why as the same size, off set and manufacture wheels have been fitted to another Harrison recently.

Merv

Merv

[400TT]

Merv, I expect you have checked the wheel offset/backspace to make sure it's the same as that other set of wheels.

Is there is any difference in the rear-ends? Are they both Skyline R32 rear-ends, yours doesn't have the R33 rear. The R33 rear may be wider.

Considering it won't look quite right, I would just extend the lip on the rear. Going to a full size 427 SC lip on the rear should easily fix the problem and enhance the look of the car as well in my opinion. More money though.

[Merv and Sharon]

Thanks Craig. yes I have checked the offsets against those of the other Harrison owner. Interesting about the rear ends though will need to check with Warwick! Not sure how one gets the extra lip for his body either.

Merv

[sideshow]

if u drop a straight line from edge of rear guard flare what ever u call it

no part of the wheel can touch that line

so basically tyre cant protrude past guard so either refibberglass the guard or get a

thinner tyre

[Merv and Sharon]

Have lowered it to the ground and things improved. Fronts seem OK but the right rear is still out at the top by at least 1 CM, even with the negative camber that is on it now. Strangely the L rear seems just OK. Sill hight seems fine at 180cm without motor.

Perplexing!

[Tenrocca]

Originally Posted by Merv and Sharon

Sill hight seems fine at 180cm without motor.

Perplexing!

Man you have that baby jacked up...wicked!

Seems to be a common problem with a few kits that the bodies arent centered right on the chassis - Took ages to get mine straight - bloody annoying.

Depending on the wheels you may be able to get the contact hub mating face machined a little, and maybe ge teh hub nmachined a little too to bring it in when you need too. As the suspension works up as youve seen, it will pull the wheel in - I think if you dont have clearance issue with the gaurds, and can possibly borrow a set of rear wheels for rego - having the wheels as far out as possible looks good IMHO. I tries to push mine to the limit.

You cant tell me these rears a fully inside the gaurds at ride heigt - I think it looks tough:

[Merv and Sharon]

Thanks for that. There may be a centering problem, as the LHS is definitely better on this Harrison. May be some scope for improvement when the suspension and toe are set up. The rear end is the R32. Some space for machining the back of the wheel and maybe the hub, or else as you say, use smaller wheels for rego OR get some flare on the guards!

Merv

[martrogers]

This does not seem to be your problem but worth mentioning anyway.

When working out my offsets/backspace I realised from the rim cross section drawings I was sent that whilst offset is based on the rim width which is measured between the inside of the rim flanges, backspace is measured to the outside of the inboard rim flange. In my case the rim flange (and its flare) was 13mm so this needs to be taken into account when converting offsets to backspaces if you're tight for space.

[sambo]

Merv, in your investigations did you happen to find any difference between the R32 and R33 rear ends? Mine's R33 so that's why I'm asking. I think after reading this thread I'll be carefully measuring both sides before placing my wheel order.

[400TT]

Sambo, I've been told the R33 rear is the same width, but considering the apparent size difference between R32 & R33 I'm a bit suss.

Yeah, best idea is to measure and be sure.


Merv, are you going to register the car in gelcoat or will it be painted?

You may get up to 5mm by machining the wheels, but doubt you will get any out of the hubs/rear-end without major modification.

Actually have you checked that the rear wheels are pushing on flush to your hubs? That should be obvious though.

Just seems weird that there is a difference.

If it helps we could try one of your wheels on my brothers car. I'm up at his place most Saturdays helping with the GT40. Plus we could give an opinion on whether it would pass rego.

[Merv and Sharon]

Thanks again guys. Yes the wheels are all flush on the hubs. There is some scope for minor skimming of the back of the wheel face but not much as there is only about 5-6mms between the caliper and the wheel now. I did measure the backspaces carefully and checked when they arrived. I checked with Warwick and mine is the R32 rear end (the spring passes thru the upper suspension arm). The ride height is 190 now and should be a bit lower when motor and g'box are in and that should also fold the wheels in a bit more.

Still a mystery! The brake rotors are new ones and I can't imagine that one could take (or want to!) much off them. The LHR side is better than the Right, which also puzzles me. I am starting to like the look though! Maybe I should bring one wheel down to check. I am planning to have the motor dropped in when it arrives in a few weeks and and could get this damn wheel aspect checked then. I was going to have it painted before rego but could delay that.


Merv

[byroncobra]

Hey this is sounding very familiar!
How did your rear end end up Merv?

[Merv and Sharon]

It was touch and go Greg. I DO have the R33 rear (was wrong above). In Indo Papua now so apols for the delay. Not sure what off sets/backspaces/tyres you used and whether the problem is front and rear? I had my suspension set up in a preliminary way by Warwick's suspension guy at Labrador (very cheap) and then finished the job up the Sunshine Coast with a local specialist. The wheels tucked in a good deal and they angle out a little at the base anyway with the suspension settings (using Warwick's suggested settings) and that seemed to do most of the rest. Ride height can also be an issue. I used the same settings and tyres as a former customer of Warwick's these were 'just' OK at rego. I would be even more conservative if I did it again (i.e., do exactly what Warwick suggested). I also suspect that the RHS rear on the Harrison is a little offset towards the centre - that is more prone to protrusion than the LHS. Importantly is was registered and drives superbly on the road - like the proverbial 'rock'. 2000ks with no probs.

Merv

[byroncobra]

Merv, I spent an interesting morning at Matts' place, aka spookypt.

We put my Dragways on his Harrison and found to my surprise that they fit fine, just tucking inside the guards.

The only explanation that was confirmed by Scott at Venom is that I must have a R33 rear end. I had been told by the guy that i bought the car from that it is an R32 and he's ordered the wheels to suit Warricks spec.

So the lesson is don't assume that what one's told is correct.

The R33 is wider than the R32 (as I think you already know)

Anyway, Matts' RF Racing 17" wheels with +50mm offset (plus a 25mm spacer) are a perfect fit. Not Hallibrands but apart from the wrong colour look pretty smick. The next question is, will Mr Cross accept spacers? If not I'll leave them off for rego.

I'll persevere as you did with your wheel combo, I still can't fathom how you tucked them under the guard, i'll revisit this after paint. She's off to Des the painter in a few weeks......should be home before Chrissy for trimming up.

[07cob]

Greg

The R32 camber arm has a 'ring' for the shock to pass through (ala the links Sambo supplied in your other post), while the R33 has a camber arm that runs around the front (or back - I'm not sure) of the shock. Given Merv's experience and yours, I guess the 32 and 33 rears are different widths.

Geof

[byroncobra]

Oooohhhhh no Geof, there goes my theory. The shocky and spring pass through the ring.
Are you sure there's not a couple of arm configurations for a R33?

[WKB]

Greg,
What chassis number have you got? Should be able to work out if it R32 or R33 from when it was made.

Warren