Haynes Forums  

Go Back   Haynes Forums > Haynes Roadster Forums > Bodywork and interior
FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1  
Old 30th June 2013, 08:16 PM
Johno's Avatar
Johno Johno is offline
Senior Member
 
Join Date: Sep 2011
Location: Lutton (East Anglia)
Posts: 497
Default Rear wheel arch width

I'm trying to sort out what wheels to purchase but I don't have my rear arches yet.
So what is the standard width from side of car to outer edge of arch for most suppliers (AGM, Equinox etc...).
With this in mind I should be able to determine what offset to order to fill out the rear arch if you see what I mean..
Also any suggestions what size wheel tyre combo to suit original MX5 speedo criteria.
__________________
Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction.
Albert Einstein

http://s1199.photobucket.com/albums/aa472/JohnoSS1/

Johno
Reply With Quote
  #2  
Old 30th June 2013, 08:40 PM
Davidbolam Davidbolam is offline
Senior Member
 
Join Date: Mar 2011
Location: Gosforth, Newcastle Upon Tyne
Posts: 856
Default

Quote:
Originally Posted by Johno View Post
I'm trying to sort out what wheels to purchase but I don't have my rear arches yet.
So what is the standard width from side of car to outer edge of arch for most suppliers (AGM, Equinox etc...).
With this in mind I should be able to determine what offset to order to fill out the rear arch if you see what I mean..
Also any suggestions what size wheel tyre combo to suit original MX5 speedo criteria.
The tyres for the speedo to read correct are 185 60 14's if this helps.

David
__________________
Click to see my build photos on Flikr

http://www.flickr.com/photos/67112582@N03/

Saturn MX5 Based Chassis, Limited Slip Diff & 2.4 Quick Rack.

Build cost.... seems to be spending more on tools than car bits at the moment! (they will be handy in the future though).
Car iva'd and passed 15/08/2014. Finished weight 572kg.
Reply With Quote
  #3  
Old 1st July 2013, 05:25 AM
Ben_Copeland's Avatar
Ben_Copeland Ben_Copeland is offline
Senior Member
 
Join Date: Feb 2009
Posts: 290
Default

Pretty sure equinox ones are 11inch wide rear wings. Although Dave will make them any width you like.
Reply With Quote
  #4  
Old 1st July 2013, 03:56 PM
voucht's Avatar
voucht voucht is offline
Senior Member
 
Join Date: Jun 2011
Location: Lautrec, Tarn (81), Occitanie, France
Posts: 879
Default

Hi Johno,

For the wheel/tyre combo, if you change the wheel size of your donor, the tyre dimensions will change too (obviously ). You have "equivalences" of tyre sizes (ie if you want to fit 15'' wheel instead of the original 14''), but of course, they are not "exact". It is just a question of how many % difference with the circumference of the original wheels you are ready to accept. I think between 0 and 3%, it is acceptable for your speedo/mileage counter to be still "correct".

I used a French website to calculate mine, but I found this one in English. It is about Miata, so it is even better for you !

http://www.miata.net/garage/tirecalc.html

If, as Ben says, rear arches are 11'' wide, you can with no problem use a 7x15 wheels, same ET (offset) as the MX5 wheels in 14'', and a 195/50-15 tyre (-0.3% difference with the circumference of the 185/60-14)

Now, if you want your wheel to be as close to the edge of the arch as possible, you will have to recalculate the ET you need. But bare in mind that not all ET are available for a given size/centre bore (register)/PCD, so, I would stick to the MX5's ET.

Hope this will help
Reply With Quote
  #5  
Old 1st July 2013, 06:28 PM
TSM Locost's Avatar
TSM Locost TSM Locost is offline
Senior Member
 
Join Date: Mar 2007
Location: Wisbech
Posts: 423
Default Equivalents

Check these out: http://www.midlandwheels.com/FitmentGuide.asp#maz
__________________
Be Lucky, Mike.
Reply With Quote
  #6  
Old 2nd July 2013, 08:59 PM
Johno's Avatar
Johno Johno is offline
Senior Member
 
Join Date: Sep 2011
Location: Lutton (East Anglia)
Posts: 497
Default

Thanks all for your advice...
__________________
Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction.
Albert Einstein

http://s1199.photobucket.com/albums/aa472/JohnoSS1/

Johno
Reply With Quote
  #7  
Old 3rd July 2013, 07:32 AM
jason 82 jason 82 is offline
Senior Member
 
Join Date: Feb 2012
Location: Coleford
Posts: 354
Default

Go for the 15 inch rims Johno, your car looks mint, it would be a real pitty not to fill those arches right out ! If you have a really understanding wife, get some magnesium alloys, they are light as a feather, keeping the weight right down just putting the idea out there
Reply With Quote
  #8  
Old 3rd July 2013, 02:55 PM
TheArf TheArf is offline
Senior Member
 
Join Date: Jan 2010
Location: Wrexham North Wales
Posts: 1,041
Default

Johno that is one seriously tidy build mate, can I just ask a quick question, what length have you made the arms for your headlight brackets and do you need to adjust them for the dia of the light unit itself.
My lights are 3.5" dia so would I need to compensate for the size but my plans are the same as yours to run the cables through the arms and keep it all minimal

Arfon

p.s sorry didn't want to distract from the original subject
Reply With Quote
  #9  
Old 3rd July 2013, 08:57 PM
Johno's Avatar
Johno Johno is offline
Senior Member
 
Join Date: Sep 2011
Location: Lutton (East Anglia)
Posts: 497
Default

Quote:
Originally Posted by TheArf View Post
Johno that is one seriously tidy build mate, can I just ask a quick question, what length have you made the arms for your headlight brackets and do you need to adjust them for the dia of the light unit itself.
My lights are 3.5" dia so would I need to compensate for the size but my plans are the same as yours to run the cables through the arms and keep it all minimal

Arfon

p.s sorry didn't want to distract from the original subject
Hi Arfon,
I think the measurement is 120mm from centre of light to edge of box, not 100% sure so will check tomorrow for you. I'm guessing this measurement is pretty standard and should be suitable for any size light.
The tube I used was 19mm same as top wishbones.
__________________
Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction.
Albert Einstein

http://s1199.photobucket.com/albums/aa472/JohnoSS1/

Johno
Reply With Quote
  #10  
Old 3rd July 2013, 09:06 PM
Johno's Avatar
Johno Johno is offline
Senior Member
 
Join Date: Sep 2011
Location: Lutton (East Anglia)
Posts: 497
Default

Quote:
Originally Posted by jason 82 View Post
Go for the 15 inch rims Johno, your car looks mint, it would be a real pitty not to fill those arches right out ! If you have a really understanding wife, get some magnesium alloys, they are light as a feather, keeping the weight right down just putting the idea out there
Hi Jason...
Gonna have a job getting that one passed the financial advisor....
Yeah I agree 15" would look good but might stick with 14" as I believe it's better to have a bit more tyre sidewall on these cars for handling.
I've been thinking about putting some 205's on the rear and 185's on the front what do you reckon?
__________________
Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction.
Albert Einstein

http://s1199.photobucket.com/albums/aa472/JohnoSS1/

Johno
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT +1. The time now is 06:57 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.