19 replies to this topic

[Thorney]

Okie, dokie, I get it now. Bad news - Lotus Oz wheels (by far the nicest) simply will not fit UNLESS you have standard suspension and have no intention of changing. It will be a tight fit but you 'should' be ok. If you have Nitron/Spax etc then forget it. I didn't get to check it on a track so you may have problems if you do. Speedline wheels will fit fine Not quite as nice as the Lotus ones but same weight. In order to fit Speedlines (or Oz) is to swap to a 4 bolt pattern. Using Lotus hubs (much much lighter than OEM - I'll weigh them when I get a chance) the rotational weight is hugely reduced (just under 5kg's a corner) Lotus disks and hubs are very very impressive and I think will make even more of a difference on a track. Now the real news. Yokohamas utterly transform front end grip , even in the wet they were more predicatable (once I got tyre pressure right). On a track they will be unbeatable (as they were on the Sprint). The rear real news is the 16" front wheel. Now I'll be honest and did think Lotus using a 16" wheel was more marketing that purposeful - how wrong I was. I went from standard to new set up and turn in was sharper, steering quicker and whole car felt more alive - Now this could be due entirely to the lower weight of the wheel but I think the smaller size is crucial here. Brooke Kensington and AmD have been marvelous, taking a chance on numerous set ups until we knew what worked. I'll write this all up of course but I wanted to post up quickly when I knew. Sounds like there may be some 5 bolt wheels coming soon, my opinion on these (all IMO of course): 1. Avoid any wheel which doesn't save a significant amount of weight on standard, nice wheels won't do anything unless they save some weight. Within reason of course, go too light and you can break a wheel - not fun 2. Go for a 16" front - it does make a huge difference 3. Swapping to 4 bolt isn't simply just a method to get other wheels. The lighter hub and disks from Lotus or others DOES make a difference and would be worth it IMO even without a wheel change (if you get my point). 4. Get AO48's. They're fine in the wet and unbeatable in the dry. I woke up this morning thinking all the effort (and considerable cost) of swapping to 4 bolt was a waste of time, however after some time on the road and an airfield I'm now convinced it is a good method of upgrading the handling of the car. I have a revived respect for Lotus, 16" front wheels aren't all hype, they do work I'm impressed.

[Ricky2772]

4. Get AO48's. They're fine in the wet

if you forget the emoticon, someone might believe you're serious...

edited to say that they are indeed fine, ..... to CRAWL home if rain happens...

048's work IF at temperature....don't forget those "cuts" are purely for homologation reasons...when you say 048, think of slicks....

Edited by Ricky2772, 05 November 2003 - 10:26 PM.

[minime]

now you understand why i want the 4 stud hubs!

[Ricky2772]

- I'll weigh them when I get a chance) the rotational weight is hugely reduced (just under 5kg's a corner)

afaik, superleggera's +048 save 3,2 kg each corner
changing to astra 4-bolts hubs requires to change discs AND AP calipers, or they can be kept?

[speedyK]

The rear real news is the 16" front wheel. Now I'll be honest and did think Lotus using a 16" wheel was more marketing that purposeful - how wrong I was. I went from standard to new set up and turn in was sharper, steering quicker and whole car felt more alive - Now this could be due entirely to the lower weight of the wheel but I think the smaller size is crucial here.

Go for a 16" front - it does make a huge difference

I have a revived respect for Lotus, 16" front wheels aren't all hype, they do work I'm impressed.

Remember when you said how 17" fronts were right for VX/Speedster 'cos GM told you how it was "engineered" for them?

This confirms beyond doubt that it was really because Opel was insisting on 17" for marketing reasons – pandering to the ignorant masses to sell more. No skin off Lotus's nose either.

Glad to have this confirmation that 16" front is the way to go. Sure you're right about the lightweight hubs too. Just wondering if I can get this passed in Switz.

Is this right now:

Speedlines: 16" front, 17" rear with Lotus 4 bolt hubs and Yoko 048's fit with standard suspension and with lowered (no fouling anywhere).
And with race suspension (lowered) still not an issue at front or rear with the above kit?

Who's going to supply this stuff, AmD? Will official confirmation of suitability for fitting to VX/Speedster be issued (essential for Switz./Germany/Austria AFAIK)?

Did you get a chance to take some pics of this on the car, Thorney? Would be v. keen to see.

[minime]

the discs have to change.....calipers are ok! i spoke to regal today about the lotus wheels and they said they could flare the arches a tad so that they could fit.....

[Ricky2772]

the discs have to change.....calipers are ok!

you saying that standard AP calipers that fit on 5-bolts hub, will ALSO fit on bog standard astra 4-bolts hubs? same 2-allen bolts caliper attachment?!?
if so, that would be great news for you guys....

[dude]

is there some special reason why you can´t have 16" in the rear to?. it would be cheaper and lighter.

[Ricky2772]

is there some special reason why you can´t have 16" in the rear to?.
it would be cheaper and lighter.

no available tyre size (like 225-50-16) in 048's and prolly in any other brand as well....
...and they won't look good!

[cheeky_chops]

i spoke to regal today about the lotus wheels and they said they could flare the arches a tad so that they could fit.....

Can you roll GRP??? And I also thought that GRP was very difficult for the paint to bond too. Even when finished it is quite brittle...

[garyk220]

the discs have to change.....calipers are ok! i spoke to regal today about the lotus wheels and they said they could flare the arches a tad so that they could fit.....

After looking again at the pictures of the Lotus OZs on paulb's car, they do look great. Do you know the offsets on these wheels?

PS Ricky, the calipers bolt to the uprights. Only the hub has to be replaced, the part the brake disc is bolted to.

[Thorney]

You can't roll plastic. Only way would be to cut away the outer arch and attach extensions (like we have on the race cars) - awful lot of effort for a set of wheels. The change to 4 bolt hubs is indeed an awful lot more than just get other wheels. Lotus hubs are far lighter (I'll try to get a piccy of them side by side). The OZ's really are nice but they really wont fit. The Speedlines get close but not close enough to cause problems. I'm sure Brooke Kensington will be happy to sort other people with hub swaps and I'll get some piccies of the silver speedlines (I'll be getting black). Re the tyres, I have to say I'm quite impressed with the performance in the wet, they do slide but its very predictable but I imagine they might be a bit of a nightmare in pooring rain.

[Ducati996Senna]

What size tyres have you fitted to the front Thorney. I can't see that the 16" wheel will improve turn in speed unless the wheel combined with a tyre gives a reduced overall diameter. Example: 175/50 17 =60.68cm overall dia 195/50 17 =62.68cm overall dia 175/50 16 =58.14cm overall dia 195/50 16 =60.14cm overall dia Therefore a wider tyre with the same aspect ratio will give a larger overall diameter. The lightness of the wheel and hub assembly will obviously reduce sprung weight and improve suspension reaction given that mods are made to compensate for this lighter sprung weight. Wheels are a personal thing and I appreciate the work that you have done in this area. However I shall be looking for 5 bolt wheels that are alot lighter than the oem. Thereby I can use my standard wheels where I foresee its use in wet conditions. Looking forward to new wheel options.

[Thorney]

hehe. OEM is 17 x 55 Yokohama set up is 16 x 50 Quite a difference.

[Thorney]

and I dont see the yoko's as being a summer only tyre, like I said, I felt they were better than OEM in the wet. I'll be running these all year round. Maybe Italian rain is wetter than British

[cheeky_chops]

Does decreasing the diameter alter the speedo/milage?? Or is that on the rears??

[garyk220]

Does decreasing the diameter alter the speedo/milage?? Or is that on the rears??

Nearside rear sensor IIRC

[Ricky2772]

Looking forward to new wheel options.

adopting the 195-50-16 front, there is the yoko 039 option... (exige standard rubber)
more an all-rounder, more cuts for better wet handling, and still decently sticky on dry.... I have a 50% worn out set in the garage, and I liked'em a lot....sure enough, I almost never drive in the wet, so 048 are the best choice for me...
039's will be discontinued soon, but for open-road usage and occasional trackdays, they are an excellent choice if adopting the front 16' inchers

[Mike9009]

Thorney What was the approx cost for this work? Could you break it down into the individual components. ie cost to change to four bolt hub, cost of disks, cost of wheel and cost of tyre. I appreciate you might not have exact figures but ball park would be good enough.... Also this route forward (weight reduction and handling improvement) shouldn't effect your insurance premiums as much as sticking an indcution kit and zorst etc???? cheers Mike

[Thorney]

Hub change (includes uprated disks) - £500 approx Tyres - £500 Wheels - £500 All approx prices.So assuming we can get a decent 5 bolt lightweight wheel it'll save you £500 but may not gain you as much rotational weight loss.