Maximum wheel widths and offsets

[Caly2c]

hello and long time no speak for some of you

Sorry for another offset/wheel thread. ive read every single other one on here but non discuss the topic in much detail.

The last time i posted was with a similar set of questions in regards to wheel fitment. If you do remember it i am still pondering my options to this day. My cally has been back on the road for a just over 12 months now. And at the time of my similar thread it was still in the build process. After having the priviliage of being able to enjoy it again my attention has turned to replacing the near 10 year old cheap and heavy off the shelf wheels with something more appealing to the eye.

I have decided that custom (or an off the shelf wheel good enough from over seas) is the way to go. I'm a bit of a fussy person and alot of the new age off the shelf stuff here in Australia still doesn't cater for 4x100 or my tastes. There is a company or 2 in the uk that seem to fit both the custom and the off he shelf critieria. One is called Image Wheels. Ive heard mixed reviews from them but they appear to be well priced for custom wheels and Rochford Tyres. The latter does BBS RS style wheels for very little money. What made me look twice however was its fitment specs.

They claim they can supply 18x8 (front) and 18x9 (rear) with an offset of ET35 that will fit Calibra 4 stud. Link:http://www.alloywheels.com/8x18_Inch_Front_9x18_Inch_Rear_Calibre_Vintage_Silver_Alloy_Wheels_Only

I have seen some Calibra's with wide wheels fitted before with no body add ons and stretched tyres with one instance 9 inch front and 9.5 rear.

Now i know ET49 is optimum so ET35 would seem out of reach but some members have no problems.

I was after some opinions on the above specs and since the avenue exists for the ability to build a wheel from scratch what would be the optimum comprimise of safety/structural integrity vs looks. Ive got some ideas of my own but i would be interested to hear your feedback

many thanks in advance

Ben

[Fraz]

Well clever people came up with the offset of the wheels. And no doubt they also spent a lot of money in testing it as well. That's why I always try to get as close to the et of 49 as I can, not easy as very few make a wheel even close to that. You may be seeing people with a lower offset but are these an every day use car or just a show car? Driving everyday on the wrong offset is a lot different to just driving it at weekends

Sent from my HTC Wildfire S A510e

[Caly2c]

From the reading i have done on the topics on this forum it appears most drive with very low offset everyday, but i agree manufacturers come to the decision of their technical specs for a reason but to see that people are able to run much lower offsets without a hitch is interesting. My car is only driven on weekends when i'm able to. Ultimately id love to be able run as wide a wheel as possible. And seeing the above link gave me a glimmer of hope that doing so may be possible. i'm hoping that someone may have come across a similar fitment or shed some light on if it could work

[Mark1]

I have 8.5"x18 on mine with the offset at ET45 and 215/35 tryes and they can rub the wheel arch on the fronts.

[Caly2c]

Hi Mark, thanks for the reply.

I see, have you modified the gaurds in any way? In trying to eliminate all variables, there wouldn't be much of an advantage being 5 stud? All the cars ive seen or heard of with wide wheels are 5 stud interestingly.

[Mark1]

If you mean the wings then no I haven't but I did find that when I changed from Toyo's to Yoko's it stopped.

[poita]

Ben I'm running 19x7.5 with ET35, tyres are 215/35/19

the fronts cleared no worries at all, we did roll the rear out about 1" from memory.

you know my suspension, but for a refresher koni adjustables with eibach springs.

get no rubbing at all.

[Caly2c]

No mods? Wow. I'll be darned if i know why my current 17x7s at ET42 scrubbed before i rolled my guards and wound the ride height up, 8.5 and no problems is impressive. In theory then i could get away with 9's on the back then? hahaha

Yeah i vaugely remember your set up Pete. But i didnt know you were at ET35 Your spring is 35mm yeah? Ive had mine rolled about 1 inch also, what has crossed my mind is good ol Ozzy Tyres has sold me a weird offset and said it was 42 things just arent adding up with my car compared to everyone else.

With the wheel i want to have as much dish but even at Et35 i would be lucky to get much i think. If you havent already noticed im trying to push the wheel fitment barrier hahaha

[poita]

TBH when I got the springs they said 40mm, it sits pretty damn low

Definitly sounds like they wheels aren't what they should be, but that does not surprise me one little bit with Ozzy Tyres

[EddeyDancer]

I'm also trying to work this ET thing out...

Maybe this diagram might help clarify...

[Caly2c]

Yeah yours does pete ive noticed, ive got 35mm rear adjustable front, its higher than what id like at the front. But the scrubbing was insane. No problems at the rear however. Back then Ozzy tyres were the only supplier. And imports were sky high. No real choice.

Thanks the the pic Eddey. Best one ive seen. I understand the whole offset thing, just want to experiment with it, looks like ET35 is the lowest possible. Ive emailed a local wheel importer my requirements their liasing with their European supplier so ill see what they come up with. Damn GM's unconventional offset!

[EddeyDancer]

Mate...

What size tyres do You intend on fitting?
Will they be the same front and rear, or fats at the back???

I currently have ET 40 with 225/40 R18 front and back...
But I feel that 215/40 R18 would be much better for the front, as 225 is heavy on the steering...

I'm going to try 235's on the rear very soon, just not decided on which Mags they'll be better fitted on...
The ET 40 or the ET 45??? Seems like the ET 40 from what I gather...

So I'm trying to work out this ET thing, to avoid scraping...

[poita]

That's right you put the H&R's in the front from memory?

I Imported the wheels myself from the UK Ben, www.bkracing.co.uk

The guys where great to deal with and turned up pretty quick from purchase date

[Caly2c]

Mate...

What size tyres do You intend on fitting?
Will they be the same front and rear, or fats at the back???

I currently have ET 40 with 225/40 R18 front and back...
But I feel that 215/40 R18 would be much better for the front, as 225 is heavy on the steering...

I'm going to try 235's on the rear very soon, just not decided on which Mags they'll be better fitted on...
The ET 40 or the ET 45??? Seems like the ET 40 from what I gather...

So I'm trying to work out this ET thing, to avoid scraping...

215s most likely, just depends on what width i go with, with as much as 8.5 possible id be tempted to at least go 8. With 8.5 or even 9 on the back. Im thinking the latter must be possible in some way if someone is advertising a package. I havent really decided on the rims either. The new TSW forged stuff looks nice, and i have looked at some UK stuff. Will all depend on what answer i get back from the local guy. I'm a big dish fan, but i'm not sure i'm going to be able to get the results i want so it may be a non dish style rim with a bit of concave. Yeah i was thinking ET40, Pete's running ET35 as he stated with no issues.

Same here mate, i'm trying to do as much research as possible so i get the clearence right.

That's right you put the H&R's in the front from memory?

I Imported the wheels myself from the UK Ben, http://www.bkracing.co.uk

The guys where great to deal with and turned up pretty quick from purchase date

Thats them, it was the only coilover kit readily available here too, got them (along with the Rieger stuff) through TCCA in Sydney. Not sure if their still around. Only has adjustable front, but the rear is well matched. Rides beautifuly. I'll shoot them an email i think mate, see what they have to say about it. Yeah i remember they arrived pretty quick, good shipping price from memory too. Did you have to pay custom's duty??

[poita]

nah no customs fee's as the wheels came in under $1kAUS at the time

from memory it was 444 pounds for the wheels and 400 pounds for freight

about $1500aus landed, aussie dollar is better now so would be cheaper

mine are the BK299, but I had them repainted