Best tire size and spacer setup for Turbo Twist wheels?
#31
04-05-2017, 10:27 AM
Agree on 18s. I went to 19s for a while & came back to 18s. Much depends on the road surface you drive on. If it's not smooth, you will be jostled by the reduced compliance from shorter sidewalls.
#32
04-05-2017, 12:23 PM
19's are good, you just need to find the right tire combination. I spent way too much time researching this and explored every option.
If you go with 18's:
Stock 225/40/18 or 235/40/18 fronts along with the 295/30/18 PS2 are best in this size.
GT2 sizes 245/40/18 front with 315/30/18 in PS2 or BFG Rival tires are best.
If you go 19's:
Best fit but hard to get 235/35/19 with 315/25/19 Sportcontact 6 ordered in from Germany are best in this size but low profile sidewalls have rougher ride and less grip. Toyo and Nitto make these but are poor tires.
Next best fit 245/35/19 with 295/30/19 Fronts are .2 inch smaller than rears so front drive may have less efficacy but these are available in many great brands and are very close in size. Won't fit on 12 inch rims though.
Next is 245/35/19 with 305/30/19 Rears are .5 inch taller than fronts which is pushing it, but I haven't heard of anyone ruining their diff with this setup. Lots of rubber on the road and plentiful tire choices. I like the Michelin PSS or new 4S for street tires and the Brigestone RE-71 or Yokohama AD08 are great sticky aggressive tires with awesome sidewalls that will work on track.
If you go with 18's:
Stock 225/40/18 or 235/40/18 fronts along with the 295/30/18 PS2 are best in this size.
GT2 sizes 245/40/18 front with 315/30/18 in PS2 or BFG Rival tires are best.
If you go 19's:
Best fit but hard to get 235/35/19 with 315/25/19 Sportcontact 6 ordered in from Germany are best in this size but low profile sidewalls have rougher ride and less grip. Toyo and Nitto make these but are poor tires.
Next best fit 245/35/19 with 295/30/19 Fronts are .2 inch smaller than rears so front drive may have less efficacy but these are available in many great brands and are very close in size. Won't fit on 12 inch rims though.
Next is 245/35/19 with 305/30/19 Rears are .5 inch taller than fronts which is pushing it, but I haven't heard of anyone ruining their diff with this setup. Lots of rubber on the road and plentiful tire choices. I like the Michelin PSS or new 4S for street tires and the Brigestone RE-71 or Yokohama AD08 are great sticky aggressive tires with awesome sidewalls that will work on track.
Has anyone tried to get the car on the lift (or put up on 4 jackstands), wheels off the ground with engine started and put in gear to see what amount of torque the front is producing when the car is lightly putting along? I bet that if you simply put the car in first and let the rears turn with idle RPM, you'll be able to grab the fronts and hold them in place. Have someone slowly increase rpm and see if the fronts start producing much torque. Simple test to give you an idea to check the system... Takes 15 minutes to accomplish..
Last edited by pwdrhound; 04-05-2017 at 03:02 PM.
#33
04-05-2017, 01:16 PM
Registered User
I think mine works. Last I drove it I would kick the rear out on some corners and I could feel the front pulling me along. Also when I would floor it in the rain I never got significant wheel spin and I was running 1.2 bar. I know my car used to have 19's on it from the previous owner that had 225/40's up front with 305's in the rear.
I forgot to mention the 225's, they are 26.1 in tall and they work well with the 295's and 305's but is a skinny tire that will push.
I forgot to mention the 225's, they are 26.1 in tall and they work well with the 295's and 305's but is a skinny tire that will push.
#34
04-05-2017, 02:26 PM
I'm running 225/40/19 and 295/30/19. Gives me the same sidewall height + comfort as stock and also gives me the same overall diameter front to rear for the AWD. My setup is a couple pounds lighter even though 19" vs stock hollow spokes (yes, I weighed them). My car is a street car, the setup works perfect for my application. 
#35
04-05-2017, 06:34 PM
Registered User
Join Date: Jan 2014
Location: California
Age: 69
Posts: 265
Rep Power: 45 
To test the viscous coupling: on a nice smooth and level concrete floor, put a floor jack under the rear cross member and jack it up enough to lift the rear tires off the ground. I put 1x4 wood in front of the front wheels to stop the car from moving. Get in start it up, turn PSM off, let out the clutch in first gear. the car will push against the the 1x4s but not climb over it? Be carefull!!!!!! I have done this and see a a fair amount of torque but not enough to climb over a 3/4 thick piece of wood, so not all that much. Give it a try, only takes about 10 min. to check it out. I would like to know how other peoples cars respond to this.