hub offsets/ tire clearence

[upnorthelan]

So I've read alot about Elan and +2 hubs in the archives and would be greatful for final confirmation before ordering some new minilites. I'm currently running a S4 with Avon ACB 9 fronts all around (5.5 x 22"), stock flares (wings?), stock 4.5" steel wheels and experiencing slight rubbing against the rear springs under hard cornering. I have the narrow spring kit.

Minilite apparently cannot change the backspacing for a knock on wheel to alieviate the issue so I thought switching to +2 hubs may gain me the clearence I'm seeking. (Minilites will be 6 x 13", 26R flares to accomodate).

From what I've read...
My Elan being an 036 w/ knock on hubs, I have the same bearings (GT 6) as a +2?

The front +2 hubs are 3/16" outboard compared to the Elan and the rears 7/8"?

Thanks,
Mike

[CBUEB1771]

Tire to spring clearance will not be the biggest problem. With 6X13 Minilites and +2 rear hubs you will likely have fouling of the outboard control arm bolts against the inner wheel rim. The 5X13 Minilites should not have this problem, they fit my +2 without problem whereas 6X13 do not fit. I say all this assuming you have standard rear control arms. An option is to use the adjustable versions from Spyder (and likely other usual suspects) which use spherical rod ends for the outboard pivots. These will clear almost any alloy wheel.

[upnorthelan]

Thanks Russ,

I have standard a-arms, but use a low profile aircraft bolt that I hope will negate that clearence issue. I may have misspoke, Minilite cannot change the backspacing (4.125") which is the same as my steels, so all the extra meat will be outboard (hence the flares). That's why I'd hoped +2 hubs would push things out even further to help with the above issue as well as tire clearence.

Mike

[upnorthelan]

Ah... it took me a minute to process that. Aluminum wheels will be much thicker than the steels, shrinking the inner lip diamiter to foul the bolt, provided it's a large head?

[CBUEB1771]

Ah... it took me a minute to process that. Aluminum wheels will be much thicker than the steels, shrinking the inner lip diamiter to foul the bolt, provided it's a large head?

Exactly. The +2 hubs will certainly help with clearance to the spring but not enough to alleviate the control arm bolt interference. It just dawned on me that something like ARP bolts with the reduced 12 pt head would help quite a bit.

[upnorthelan]

Excellent, thanks again Russ!

Lots of things to consider when doing this project. I'm a young art teacher with limited funds and want to make sure I can bight all this off. It'd probably be smarted to switch to bolt on hubs and have more wheel options, but I'm a sucker for aethetics and love the knock ons.

Mike

[cabc26b]

Mike ,

You can in machine down the outer lugs on the control (right side) . For completeness I like the spherical inside the outboard lug and the bolt head recessed into reduced outer lugs - top left. Stock is bottom left , lots of making room on the wheel and bolt-head to make work with 5.5 inch alloys and stock fenders - messy.

George

[CBUEB1771]

Mike,
I posted a couple of images here showing the difference in clearance between the 5 and 6 inch wide Minilites:

elan-f15/inch-alloys-for-t17440.html

Minilite used to be pretty accommodating about producing different offsets.

[upnorthelan]

George,
Thanks for the options. I wanted to get in touch with you again about the gussets/reinforcements you did to your maroon car. I plan to have the body off over winter and want to strengthen my frame. You previously sent me great pictures illustrating weak areas that I've since lost years ago.

Russ,
Nothing works better than actually seeing it! The 100mm backspace looks ideal. Minilite is saying they can make me a wheel @ 105mm backdspace and no smaller which may still work providing I find +2 hubs.

Thanks again,
Mike

[PA]

I have also need looking at this possible problem.

The biggest problem is the internal diameter of any cast alloy wheel at the inner rim so that it does not foul on the wishbone and the bolt heads. My estimates suggest that the internal diameter of the wheel needs to be 317mm to 320mm to clear the wishbone and bolts at this point. Without the wishbone being modified.

Some 20 years ago I bought some Revoloution RFX wheels for my road elan (I have since sold the car). These wheels just fitted over the wishbone without the bolt head touching the rim these wheels had an internal diameter at the rim of 320mm and a back space of 110mm they fitted on standard original elan knock on hubs. They were a 5 inch wheel and allowed a 165 70 profile tyre to fit in a standard S4 rear wheel arch.

The plus two hub pushes the wheel out further and widens the rear track. Depending on what tyre size you want to use will start to give you trouble fitting inside even a 26r style wider arch.

On my car I am trying to work out what is the best back space and wheel to use. I plan to use a 6 x 13 wheel with a tyre up to a maximum width of 205 60. I have a set of wider 26 r rear arches which I have yet to do a final fix to the body. I have bolt on rear hubs on the car.

My reckon at this stage I need a wheel with an internal diameter of 320mm at the inner rim and back space of between 101 and 109mm. This will then allow me to get the 205 width tyre in the arch.

I would be interested in others experience with rear wheels and race elans with wider tyres.

I do not know the dimensions of the 26r wheels offered by TTR and Kelvedon and what the backspace and internal rim diameter is. As these wheels on 26r cars allow a wider tyre to fit in a 26 r arch. Given the race series these cars run I doubt that modified wishbones with rod ends fitted to the outer fixing point on the wishbone would be allowed.

The car I am building will be a track only car.

Regards

Paul Aston.

[elj221c]

Paul,

I have 7" JAP (JAPearce) rims on the rear.

The set of wheels that came with the car have a stepped inner rim and measure 12 1/2" inside with a set of 3 5/8". Picture 2. The front rims are 6" but if you need measurements from those there will be a delay as they are not accessable at the moment.

The other set I bought a couple of years ago (all 7") have a tapered inner rim after the first 1/2 or so and measure 12 5/8" with a set of 3 9/16". Picture 3.

Both have plenty of clearance with standard bolts with a 1/4" head depth and a 1/16th" washer with standard bushes.

They fit under flares but not 26R. Picture 1. Tyres are 205/60/13. (the car is jacked up, they fit better than shown!)

[upnorthelan]

Paul,
I'm hoping to run a 205/60 as well. A friend of mine casts mag 26R wheels for Dave Bean. He quoted me a backspace of 4.5"! You can imagine how outboard those hubs must be. Apparently inboard clearence is still very tight. I went ahead and ordered a set of peg drive minilites 13x6 with a 105mm backspace. I'll deal with any potential control arm interference when they get here. I can put some pics up once things are sorted out.

Mike

[blacklotus]

Tire/Rim clearances just keep on rolling along---I am also looking to put knock off Minilights on my S4.( without flares) I was planning on using the +2 5.5J version so as to get some more rubber on the road. I have the narrow springs. Is the Minilight rim too thick at the A arm in that standard size?
Thanks Very Much
R

[upnorthelan]

I don't think the +2 alloy wheels would be a thiner casting than any other aluminum wheel. I do believe that lotus split the difference between 4.5 and 5.5 wheels, adding .5" to either side. That'd be a backspace of ~ 4&5/8. You'd have to use +2 hubs. Those wheels seem pretty hard find. They are beautiful though!

[bettlesr]

If you are using the Spyder double A frame rear suspension, the upper bushing housing also fouls the inside of the knock on Minilite 6" x 13" wheels. I had to grind a fair amount off of the upper bushing housing as well as the normal lower control arm ends and bolts. I didn't want to cut into the wheels. I run 185-60x13 A048 Yokohama tires and 26R flairs. No clearance problems in the wheel wells.