Wheels

[prezoom]

For the life of me, I have never understood why anyone would add weight to their flywheel. Increasing the size of the wheels, equals more weight that has to be turned, and stopped. Same said for larger, heavier, tires. Add them up, Elans have 5 flywheels, along with most other cars.

Rob Walker
26-4889

[holywood3645]

Rob, He has 190 bhp, and will need to get it to the ground.
James

[holywood3645]

Looks like revolutions knockons are an option in the UK
James

[msd1107]

Rob makes a good point about the effects of larger wheels and tyres. One well regarded improvement is replacing the heavy steel flywheel with a lightweight aluminum one (or a machined and lighter one).

There is a down loadable spreadsheet at elan-f15/updated-spreadsheets-t18445.html that has the capability to estimate acceleration times and allows the user to change wheel weights, tyre weights, flywheel weights, etc and see the effect on acceleration times. There are also other tables for the curious.

The tyre manufacturers website will often have technical information on each of their tyres, which usually includes weight. So for any tyre in which you are interested, you can see the projected weight.

Also to be considered is the effect of tyre size, especially as they affect engine RPM on the road. Some members run tyres as small as 175/50-13. More commonly used is 185/60-13. Both of these are substantially smaller than the standard 155/165-13 tyres used as stock.

There is also another down loadable spreadsheet at post82912.html (20080411zGearRatios.xls down at the bottom). One sheet is TiresS or tyres sorted by rev/mile. If you key in an existing or prospective tyre size in the Gearbox sheet, the TiresS sheet will give you the sizes sorted, with an indication as to which sizes are closest (or how far apart they are)

Starting from a relatively standard 155-13 tyre (912 rev/mile), possible choices are 185/60-14 (915 rev/mile), and 185/55-15 (904 rev/mile). If you run 165-13 tyres (887 rev/mile), close choices might be 185/70-13 (893 rev/mile), 175/70-14 (880 rev/mile), 185/65-14 (884 rev/mile), 175/60-15 (893 rev/mile), or 195/55-15 (893 rev/mile).

So, do the analysis and come up with an acceptable to you choice.

Cheers,

David
1968 36/7988

[holywood3645]

No argument from me with Rob's theory, or the points you make. The idea of getting 190 bhp from what basically is a detuned F2 engine to the ground through 155x80 tires seems pretty crazy. Im not saying you or Bob are suggesting Ian does that. The whole engine, transmittion, diff, and wheel/tire package needs to be optimised, for max performance. And Ian 'IS' the man to do that.
I think Ian is just asking about peroid looking wheel options for his elan with wide arches (they are much wider than the 26R style) and is going to have some serious HP
James

[garyeanderson]

Roy Jewell and I both have these Jap Magna wheels, 7" in the back and 6 up front. I don't know how they will work but my guess is with the Plus2 rear hubs (an extra 5/8 inch per hub added width to the rear track) they will fill the rears and not add a lot of "flywheel" to the 4 corners. I still don't know if it will be street driven but the wheels are period correct and some have turned up on "the bay" in the past 10 years. Not very common but wide knock ons are limited. Bolt ons wheels offer a wider selection, Panasport Ultralites are an option about 9 pounds each for a 13 x 6.

Gary

[prezoom]

I have no argument with matching tire size with horsepower. James, install that 2L BD engine, and I'll buy your new Minilites, you are going to need a whole lot more wheel/tire. My point was, if you have a low horsepower car, plus 1 sizing, going up an inch in diameter and the subsequent increase in combined wheel/tire weight, will generally diminish performance. There was an excellent article in Grassroots Motorsports a few years ago, increasing wheel/tire size on a Miata/MX5. As the weight of the wheel/tire combination increased, the subsequent lap times went up over the factory setup. I know if I changed my KO steel wheels for something lighter, I would gain performance, if only slightly. I am sure mentally, the performance increase would be huge.

Rob Walker
26-4889

[Tahoe]

I have no argument with matching tire size with horsepower. James, install that 2L BD engine, and I'll buy your new Minilites, you are going to need a whole lot more wheel/tire. My point was, if you have a low horsepower car, plus 1 sizing, going up an inch in diameter and the subsequent increase in combined wheel/tire weight, will generally diminish performance. There was an excellent article in Grassroots Motorsports a few years ago, increasing wheel/tire size on a Miata/MX5. As the weight of the wheel/tire combination increased, the subsequent lap times went up over the factory setup. I know if I changed my KO steel wheels for something lighter, I would gain performance, if only slightly. I am sure mentally, the performance increase would be huge.

Rob Walker
26-4889

Here is the GRM article. http://grassrootsmotorsports.com/articles/speed-holes/

[Ianashdown57]

Hi,

I think my goal is to build a car that is 'essentially' what an Elan might have been had Lotus continued to build them and added some newer technology parts as they became available. I want to retain the handling charachteristics of the Elan, but with more HP, and make it so that the edge of the performance can be reached without having to be at lunatic speeds. So a little bit larger tires but not huge.

So, having said all that it looks like 26R sizes are probably where I'll end up. Minilite style or 26R style wheels are edging in to the lead at the moment. As far as bodywork goes I think the 26R wheel flares are very good looking, but they are un-godly expensive from Bean for what they are; 3 ply fender overlays! I think a large part of the cost is shipping them from the UK, does nobody make them in the US?

As for adding wheel size and losing performance. I think this is a compromize that has to be made. But going up 1" in diameter and a couple of inches in width shouldn't add too much in rotational inertia. The trade off will be a reduction in overall weight by using aluminum gearbox and differential housings.

Keep the ideas and comments comming.

Ian

[collins_dan]

http://www.ebay.com/itm/Lotus-Elan-S1-S ... 1655400%26

You might try the guy selling the air dam on ebay. I have corresponded with him and he has some fender molds, not sure if he has them for 26Rs.

Dan

[upnorthelan]

I just got a set of 26R flares from Curtis Unlimited, in Euricka CA. I'll have to find their #, no website. Cost was 1/3 of Bean or Tony and they were beautiful!

I went the minilite route 6x13 knock ons and they look great under the new bodywork.

Mike

[Tahoe]

I just got a set of 26R flares from Curtis Unlimited, in Euricka CA. I'll have to find their #, no website. Cost was 1/3 of Bean or Tony and they were beautiful!

I went the minilite route 6x13 knock ons and they look great under the new bodywork.

Mike

I was just going to suggest them. I recieved an email from them last night but didn't get a price from them for the 26R flares. I'm taking a guess but I think they are around $500 for a set. Mike, can you confirm the price? They are night owls so call late. I recieved the email at 4a.m.

Contact info is:
Bert and Fay
Curtis unlimited
707-443-8523 btwn 3 pm and 3 am Pacific time

[upnorthelan]

Russ,
Believe it or not, it was $500 including shipping all the way to Michigan! Before finding the Curtis' I was going to make a mold of a friend's flares because I couldn't/ wouldn't caugh up the going rate.

Here's a picture of them. Glasswork done on the insides, wheelwells rebuilt and waiting for the top seems to be fared in. I'm very happy with the Minilites and they DO clear the lower control arms on the rear just.

Mike

[Tahoe]

Russ,
Believe it or not, it was $500 including shipping all the way to Michigan! Before finding the Curtis' I was going to make a mold of a friend's flares because I couldn't/ wouldn't caugh up the going rate.

Here's a picture of them. Glasswork done on the insides, wheelwells rebuilt and waiting for the top seems to be fared in. I'm very happy with the Minilites and they DO clear the lower control arms on the rear just.

Mike

Mike,

Very nice! Did you modify your front bumper or did you buy a 26R one? I assume Curtis has the bumper as well but I never inquired.

,Russ

[upnorthelan]

Russ,
I chopped my old bumper upon the advice from a friend.
Because there's so much variance in fit, I opted to hang
the front "fenders" first, and then cut the bumper, wax the
new bumper pockets, then laid new glass to mate up with
the remains of the bumper to ensure a really nice fit. I've seen
some 26r bumpers that don't appear to fit well and wanted
mine to look right. That and the fact that I'm cheap and have
more time than money:)