MR2 Roadster Owners Club

The Workshop => Performance Related => Topic started by: Smithy on April 11, 2021, 10:24

Title: Anyone running a square set up on 15"?
Post by: Smithy on April 11, 2021, 10:24
I have my eye on a set of team dynamics 15" but not sure how it will handle. I have a standard FL set up at the moment.
Title: Re: Anyone running a square set up on 15"?
Post by: SV-3 on April 11, 2021, 10:32
Quote from: Smithy on April 11, 2021, 10:24I have my eye on a set of team dynamics 15" but not sure how it will handle. I have a standard FL set up at the moment.
As the Beatles sang: "Let It Be" ;)
Title: Re: Anyone running a square set up on 15"?
Post by: Ozzy on April 11, 2021, 11:52
I did briefly many years ago when I got my first MR2 roadster. It was very tail happy, even in the dry when pushed or driven enthusiastically.

I have the stock 15" staggered PFL wheels on my current mr2 with TR1 tyres and it just sticks to the bends. Amazing grip in rain also, so the difference between the two is night and day.
Title: Re: Anyone running a square set up on 15"?
Post by: Roj on April 11, 2021, 12:20
One sized glove doesn't fit all.

What will be your intended use? Some have had good results going 205 square but it depends on what you want from the car. Going square should reduce understeer and give a sharper turn in at the expense of outright lateral grip, dependent on what sizes you're going from and to.

Unless you're specifically looking to change the characteristics on track/sprint/hillclimb etc. you're probably best sticking with a stagger (IMO).
Title: Re: Anyone running a square set up on 15"?
Post by: Dev on April 11, 2021, 16:00
There are many that have gone with a square set up without too many issues and there are some advantages if you race. Larger tires increase unsprung weight and reduce the nimbleness which decreases the fun factor.
 
The reason you go staggered or for a smaller width tire is for fun. It makes the car feel alive and you can dial out the understeer easily if its a bother with adding negative camber up front.
 The way the car turns feels more like a nimble shopping cart than a feeling of a delayed response.

 If given a choice I would want a tire that grips better in small sizes than wider tires.



Title: Re: Anyone running a square set up on 15"?
Post by: Smithy on April 11, 2021, 18:09
Thanks everyone. I have a standard FL set up at the moment and I love the way it handles. The wheels I have seen for sale are a good price but at 15s all round. I don't want to change just because they look nice only to find I've lost the special feel my car has now. My car won't see a track .
Title: Re: Anyone running a square set up on 15"?
Post by: 1979scotte on April 11, 2021, 18:30
Loads of us have 15 all round that's standard for pfl cars.
You don't have to fit the same size tyres

185 205 are what we all use on pfl.
Title: Re: Anyone running a square set up on 15"?
Post by: Smithy on April 11, 2021, 19:07
Thanks Scotte and Dev.
Title: Re: Anyone running a square set up on 15"?
Post by: McSmallface on April 11, 2021, 20:36
Like the previous gents have pointed out you can run a square setup and then maintain the stagger with the tires as for example a 6.5 wide rim could accept a 185 tire on the front and 205 tire on the rear. The only other thing to would need to do it you wanted to maintain the matching front to rear track width is to either get a rear wheel in the same size as the front but with a lower offset or pop a spacer on the rear wheel to bring the rear out a bit.
Title: Re: Anyone running a square set up on 15"?
Post by: m1tch on April 13, 2021, 15:41
I am running a square setup in terms of wheels but running 195 front, 225 rear so same wheels, staggered tyres.
Title: Re: Anyone running a square set up on 15"?
Post by: Smithy on April 13, 2021, 19:48
This Friday I'm picking up a set of 15s with the tyre staggered as mentioned above. I will keep my stock FL set up for winter. Wasn't really looking for wheels but they just came up at such a good price. I'm looking forward to seeing the difference if in handling if any.
Title: Re: Anyone running a square set up on 15"?
Post by: Dev on April 14, 2021, 00:37
Quote from: m1tch on April 13, 2021, 15:41I am running a square setup in terms of wheels but running 195 front, 225 rear so same wheels, staggered tyres.

I thought square meant same width tires all around unless I am mistaken.   
  I know of double stager which is different tire width and different wheel hight. Or triple stagger which is different tire width, different wheel width and different wheel hight which is what the FL car has.

Title: Re: Anyone running a square set up on 15"?
Post by: Roj on April 14, 2021, 07:23
Quote from: Dev on April 14, 2021, 00:37
Quote from: m1tch on April 13, 2021, 15:41I am running a square setup in terms of wheels but running 195 front, 225 rear so same wheels, staggered tyres.

I thought square meant same width tires all around unless I am mistaken.   
  I know of double stager which is different tire width and different wheel hight. Or triple stagger which is different tire width, different wheel width and different wheel hight which is what the FL car has.



That's my understanding too, square set up refers to the tyres, not the wheels.
Title: Re: Anyone running a square set up on 15"?
Post by: Nvy on April 14, 2021, 09:05
Quote from: Dev on April 11, 2021, 16:00There are many that have gone with a square set up without too many issues and there are some advantages if you race. Larger tires increase unsprung weight and reduce the nimbleness which decreases the fun factor.
 
The reason you go staggered or for a smaller width tire is for fun. It makes the car feel alive and you can dial out the understeer easily if its a bother with adding negative camber up front.
 The way the car turns feels more like a nimble shopping cart than a feeling of a delayed response.

 If given a choice I would want a tire that grips better in small sizes than wider tires.


dev, Can u elaborate on the bolded part? I have this with a square setup at the moment(winter tires) but when I change to the summer ones, it is less pronounced but still not confidence inspiring. I have same rims back to front but no spacers, do you think adding a spacer will fix it? Tires are 185/55/15 and 205/50/15 Yoko Ad08r both on 7" rim and was thinking of adding 13mm spacer in the back.
Title: Re: Anyone running a square set up on 15"?
Post by: JB21 on April 14, 2021, 09:36
I'll be running a square set-up on my next track day with my 2ZZ track car. 205 equivalent slicks on 7J rims.

I currently run 3 sets of wheels.

Wets on FL wheels - Rainsport 5 - front 195/50/15 - rear 215/45/16

Road/damp/cold on 7J OZ wheels - Nankang AR1 - front 205/50/15 - rear 225/45/15

Dry on 7J OZ wheels - Hankook Ventus F200 slicks (medium compound) - 200/580/15 square


Title: Re: Anyone running a square set up on 15"?
Post by: Dev on April 14, 2021, 13:36
Quote from: Nvy on April 14, 2021, 09:05
Quote from: Dev on April 11, 2021, 16:00There are many that have gone with a square set up without too many issues and there are some advantages if you race. Larger tires increase unsprung weight and reduce the nimbleness which decreases the fun factor.
 
The reason you go staggered or for a smaller width tire is for fun. It makes the car feel alive and you can dial out the understeer easily if its a bother with adding negative camber up front.
 The way the car turns feels more like a nimble shopping cart than a feeling of a delayed response.

 If given a choice I would want a tire that grips better in small sizes than wider tires.


dev, Can u elaborate on the bolded part? I have this with a square setup at the moment(winter tires) but when I change to the summer ones, it is less pronounced but still not confidence inspiring. I have same rims back to front but no spacers, do you think adding a spacer will fix it? Tires are 185/55/15 and 205/50/15 Yoko Ad08r both on 7" rim and was thinking of adding 13mm spacer in the back.

 Less confidence could be due to many things.  What tire pressures are you running and what is the load rating of the tires?

Less responsive or a delayed response can be a result of two things. More tire width in the front and more negative offset of the wheels.  If you add a spacer you will increase the negative offset.

  When this happens you will have a feeling of more stability but your steering wheel will have less feedback.

 But its much more than that. When you change the offsets you  change the scrub radius which can make a profound difference on how the car handles because it changes the geometry of the whole suspension including the spring rates. It is one of those modifications that can radically change the way the car feels depending on how much or how little so you need to carefully consider.

 Before I would add a spacer I would work on other things since you are using stock sizes it shouldn't be this bad for you and it could just be an alignment issue.

Title: Re: Anyone running a square set up on 15"?
Post by: Nvy on April 14, 2021, 13:44
Quote from: Dev on April 14, 2021, 13:36
Quote from: Nvy on April 14, 2021, 09:05
Quote from: Dev on April 11, 2021, 16:00There are many that have gone with a square set up without too many issues and there are some advantages if you race. Larger tires increase unsprung weight and reduce the nimbleness which decreases the fun factor.
 
The reason you go staggered or for a smaller width tire is for fun. It makes the car feel alive and you can dial out the understeer easily if its a bother with adding negative camber up front.
 The way the car turns feels more like a nimble shopping cart than a feeling of a delayed response.

 If given a choice I would want a tire that grips better in small sizes than wider tires.


dev, Can u elaborate on the bolded part? I have this with a square setup at the moment(winter tires) but when I change to the summer ones, it is less pronounced but still not confidence inspiring. I have same rims back to front but no spacers, do you think adding a spacer will fix it? Tires are 185/55/15 and 205/50/15 Yoko Ad08r both on 7" rim and was thinking of adding 13mm spacer in the back.

 Less confidence could be due to many things.  What tire pressures are you running and what is the load rating of the tires?

Less responsive or a delayed response can be a result of two things. More tire width in the front and more negative offset of the wheels.  If you add a spacer you will decrease the negative offset.

  When this happens you will have a feeling of more stability but your steering wheel will have less feedback.

 But its much more than that. When you change the offsets you  change the scrub radius which can make a profound difference on how the car handles because it changes the geometry of the whole suspension including the spring rates. It is one of those modifications that can radically change the way the car feels depending on how much or how little so you need to carefully consider.

 Before I would add a spacer I would work on other things since you are using stock sizes it shouldn't be this bad for you and it could just be an alignment issue.



Yeah but the front wheel is 7" with 38 offset vs  6" 45 offset. Meaning its spaced out around 12 mm. I want to fix this first as I have good alignment. -2.2 all around and 0.1 toe in rear/ 0 toe front.
Title: Re: Anyone running a square set up on 15"?
Post by: Dev on April 14, 2021, 14:00
Quote from: Nvy on April 14, 2021, 13:44
Quote from: Dev on April 14, 2021, 13:36
Quote from: Nvy on April 14, 2021, 09:05
Quote from: Dev on April 11, 2021, 16:00There are many that have gone with a square set up without too many issues and there are some advantages if you race. Larger tires increase unsprung weight and reduce the nimbleness which decreases the fun factor.
 
The reason you go staggered or for a smaller width tire is for fun. It makes the car feel alive and you can dial out the understeer easily if its a bother with adding negative camber up front.
 The way the car turns feels more like a nimble shopping cart than a feeling of a delayed response.

 If given a choice I would want a tire that grips better in small sizes than wider tires.


dev, Can u elaborate on the bolded part? I have this with a square setup at the moment(winter tires) but when I change to the summer ones, it is less pronounced but still not confidence inspiring. I have same rims back to front but no spacers, do you think adding a spacer will fix it? Tires are 185/55/15 and 205/50/15 Yoko Ad08r both on 7" rim and was thinking of adding 13mm spacer in the back.

 Less confidence could be due to many things.  What tire pressures are you running and what is the load rating of the tires?

Less responsive or a delayed response can be a result of two things. More tire width in the front and more negative offset of the wheels.  If you add a spacer you will decrease the negative offset.

  When this happens you will have a feeling of more stability but your steering wheel will have less feedback.

 But its much more than that. When you change the offsets you  change the scrub radius which can make a profound difference on how the car handles because it changes the geometry of the whole suspension including the spring rates. It is one of those modifications that can radically change the way the car feels depending on how much or how little so you need to carefully consider.

 Before I would add a spacer I would work on other things since you are using stock sizes it shouldn't be this bad for you and it could just be an alignment issue.



Yeah but the front wheel is 7" with 38 offset vs  6" 45 offset. Meaning its spaced out around 12 mm. I want to fix this first as I have good alignment. -2.2 all around and 0.1 toe in rear/ 0 toe front.

 I made a small typo which I corrected. You increase the negative offset in regard to adding spacers or different wheel offsets.

 In regards to your question I also would like to fix my offsets as my wheels are 37 and would like to have the factory offset of 45 which is almost impossible. You can go more negative with spacers but there is no way to go positive unless the back of the wheel is machined which I heard is possible but extremely rare.
 
However if you mean you would like to fix front to back equally as far as offset to have them equal then I think that would be ideal if the rear wheels are more positive than the fronts.
 
 Do you have a problem with high speed stability? as far as confidence inspiring or is it low speed.

Title: Re: Anyone running a square set up on 15"?
Post by: Nvy on April 14, 2021, 14:18
Quote from: Dev on April 14, 2021, 14:00
Quote from: Nvy on April 14, 2021, 13:44
Quote from: Dev on April 14, 2021, 13:36
Quote from: Nvy on April 14, 2021, 09:05
Quote from: Dev on April 11, 2021, 16:00There are many that have gone with a square set up without too many issues and there are some advantages if you race. Larger tires increase unsprung weight and reduce the nimbleness which decreases the fun factor.
 
The reason you go staggered or for a smaller width tire is for fun. It makes the car feel alive and you can dial out the understeer easily if its a bother with adding negative camber up front.
 The way the car turns feels more like a nimble shopping cart than a feeling of a delayed response.

 If given a choice I would want a tire that grips better in small sizes than wider tires.


dev, Can u elaborate on the bolded part? I have this with a square setup at the moment(winter tires) but when I change to the summer ones, it is less pronounced but still not confidence inspiring. I have same rims back to front but no spacers, do you think adding a spacer will fix it? Tires are 185/55/15 and 205/50/15 Yoko Ad08r both on 7" rim and was thinking of adding 13mm spacer in the back.

 Less confidence could be due to many things.  What tire pressures are you running and what is the load rating of the tires?

Less responsive or a delayed response can be a result of two things. More tire width in the front and more negative offset of the wheels.  If you add a spacer you will decrease the negative offset.

  When this happens you will have a feeling of more stability but your steering wheel will have less feedback.

 But its much more than that. When you change the offsets you  change the scrub radius which can make a profound difference on how the car handles because it changes the geometry of the whole suspension including the spring rates. It is one of those modifications that can radically change the way the car feels depending on how much or how little so you need to carefully consider.

 Before I would add a spacer I would work on other things since you are using stock sizes it shouldn't be this bad for you and it could just be an alignment issue.



Yeah but the front wheel is 7" with 38 offset vs  6" 45 offset. Meaning its spaced out around 12 mm. I want to fix this first as I have good alignment. -2.2 all around and 0.1 toe in rear/ 0 toe front.

 I made a small typo which I corrected. You increase the negative offset in regard to adding spacers or different wheel offsets.

 In regards to your question I also would like to fix my offsets as my wheels are 37 and would like to have the factory offset of 45 which is almost impossible. You can go more negative with spacers but there is no way to go positive unless the back of the wheel is machined which I heard is possible but extremely rare.
 
However if you mean you would like to fix front to back equally as far as offset to have them equal then I think that would be ideal if the rear wheels are more positive than the fronts.
 
 Do you have a problem with high speed stability? as far as confidence inspiring or is it low speed.



Its just that I turn the wheel and the car follows after that. Not as agile that I would like it to be. What I am planning to do is to remove coilovers and fit OE shocks + springs + spacers in the back to fix back to front track width, will also lower the camber a bit -1.5 front and -1.2 back.
Title: Re: Anyone running a square set up on 15"?
Post by: Dev on April 14, 2021, 14:32
Quote from: Nvy on April 14, 2021, 14:18
Quote from: Dev on April 14, 2021, 14:00
Quote from: Nvy on April 14, 2021, 13:44
Quote from: Dev on April 14, 2021, 13:36
Quote from: Nvy on April 14, 2021, 09:05
Quote from: Dev on April 11, 2021, 16:00There are many that have gone with a square set up without too many issues and there are some advantages if you race. Larger tires increase unsprung weight and reduce the nimbleness which decreases the fun factor.
 
The reason you go staggered or for a smaller width tire is for fun. It makes the car feel alive and you can dial out the understeer easily if its a bother with adding negative camber up front.
 The way the car turns feels more like a nimble shopping cart than a feeling of a delayed response.

 If given a choice I would want a tire that grips better in small sizes than wider tires.


dev, Can u elaborate on the bolded part? I have this with a square setup at the moment(winter tires) but when I change to the summer ones, it is less pronounced but still not confidence inspiring. I have same rims back to front but no spacers, do you think adding a spacer will fix it? Tires are 185/55/15 and 205/50/15 Yoko Ad08r both on 7" rim and was thinking of adding 13mm spacer in the back.

 Less confidence could be due to many things.  What tire pressures are you running and what is the load rating of the tires?

Less responsive or a delayed response can be a result of two things. More tire width in the front and more negative offset of the wheels.  If you add a spacer you will decrease the negative offset.

  When this happens you will have a feeling of more stability but your steering wheel will have less feedback.

 But its much more than that. When you change the offsets you  change the scrub radius which can make a profound difference on how the car handles because it changes the geometry of the whole suspension including the spring rates. It is one of those modifications that can radically change the way the car feels depending on how much or how little so you need to carefully consider.

 Before I would add a spacer I would work on other things since you are using stock sizes it shouldn't be this bad for you and it could just be an alignment issue.



Yeah but the front wheel is 7" with 38 offset vs  6" 45 offset. Meaning its spaced out around 12 mm. I want to fix this first as I have good alignment. -2.2 all around and 0.1 toe in rear/ 0 toe front.

 I made a small typo which I corrected. You increase the negative offset in regard to adding spacers or different wheel offsets.

 In regards to your question I also would like to fix my offsets as my wheels are 37 and would like to have the factory offset of 45 which is almost impossible. You can go more negative with spacers but there is no way to go positive unless the back of the wheel is machined which I heard is possible but extremely rare.
 
However if you mean you would like to fix front to back equally as far as offset to have them equal then I think that would be ideal if the rear wheels are more positive than the fronts.
 
 Do you have a problem with high speed stability? as far as confidence inspiring or is it low speed.



Its just that I turn the wheel and the car follows after that. Not as agile that I would like it to be. What I am planning to do is to remove coilovers and fit OE shocks + springs + spacers in the back to fix back to front track width, will also lower the camber a bit -1.5 front and -1.2 back.

 I take it, it doesn't move as a unit. This is probably more to do with suspension than tires.
 A friend that had BC coil overs had that issue which we tried to correct with corner balancing, changing springs and alignment.  It helped and made it better but it was far from the stock suspension.  I believe it is due to the damping control as far as timing. 

 I would go back to a base line with OE suspension and see what it does before adding spacers. I bet you will see a massive difference.
Title: Re: Anyone running a square set up on 15"?
Post by: JB21 on April 14, 2021, 14:39
Quote from: Nvy on April 14, 2021, 13:44
Quote from: Dev on April 14, 2021, 13:36
Quote from: Nvy on April 14, 2021, 09:05
Quote from: Dev on April 11, 2021, 16:00There are many that have gone with a square set up without too many issues and there are some advantages if you race. Larger tires increase unsprung weight and reduce the nimbleness which decreases the fun factor.
 
The reason you go staggered or for a smaller width tire is for fun. It makes the car feel alive and you can dial out the understeer easily if its a bother with adding negative camber up front.
 The way the car turns feels more like a nimble shopping cart than a feeling of a delayed response.

 If given a choice I would want a tire that grips better in small sizes than wider tires.


dev, Can u elaborate on the bolded part? I have this with a square setup at the moment(winter tires) but when I change to the summer ones, it is less pronounced but still not confidence inspiring. I have same rims back to front but no spacers, do you think adding a spacer will fix it? Tires are 185/55/15 and 205/50/15 Yoko Ad08r both on 7" rim and was thinking of adding 13mm spacer in the back.

 Less confidence could be due to many things.  What tire pressures are you running and what is the load rating of the tires?

Less responsive or a delayed response can be a result of two things. More tire width in the front and more negative offset of the wheels.  If you add a spacer you will decrease the negative offset.

  When this happens you will have a feeling of more stability but your steering wheel will have less feedback.

 But its much more than that. When you change the offsets you  change the scrub radius which can make a profound difference on how the car handles because it changes the geometry of the whole suspension including the spring rates. It is one of those modifications that can radically change the way the car feels depending on how much or how little so you need to carefully consider.

 Before I would add a spacer I would work on other things since you are using stock sizes it shouldn't be this bad for you and it could just be an alignment issue.



Yeah but the front wheel is 7" with 38 offset vs  6" 45 offset. Meaning its spaced out around 12 mm. I want to fix this first as I have good alignment. -2.2 all around and 0.1 toe in rear/ 0 toe front.
If you want sharp turn in then more front toe out is necessary. I set mine at 0 when I first got the car and it was plain dull. Changed this to 1mm (0.09°) out each side, and it was much, much better. Now have it at 2mm (0.18°) out each side, and its so sharp. However this maybe to extreme for a road car, and will scrub the inside of the tyres.

Also I find the OE wheel offset doesn't help with feel and stability. Mine feels much more planted on aftermarket wheels with a 38ET, as it widens the axle track.
Title: Re: Anyone running a square set up on 15"?
Post by: Dev on April 14, 2021, 15:01
Quote from: JB21 on April 14, 2021, 14:39
Quote from: Nvy on April 14, 2021, 13:44
Quote from: Dev on April 14, 2021, 13:36
Quote from: Nvy on April 14, 2021, 09:05
Quote from: Dev on April 11, 2021, 16:00There are many that have gone with a square set up without too many issues and there are some advantages if you race. Larger tires increase unsprung weight and reduce the nimbleness which decreases the fun factor.
 
The reason you go staggered or for a smaller width tire is for fun. It makes the car feel alive and you can dial out the understeer easily if its a bother with adding negative camber up front.
 The way the car turns feels more like a nimble shopping cart than a feeling of a delayed response.

 If given a choice I would want a tire that grips better in small sizes than wider tires.


dev, Can u elaborate on the bolded part? I have this with a square setup at the moment(winter tires) but when I change to the summer ones, it is less pronounced but still not confidence inspiring. I have same rims back to front but no spacers, do you think adding a spacer will fix it? Tires are 185/55/15 and 205/50/15 Yoko Ad08r both on 7" rim and was thinking of adding 13mm spacer in the back.

 Less confidence could be due to many things.  What tire pressures are you running and what is the load rating of the tires?

Less responsive or a delayed response can be a result of two things. More tire width in the front and more negative offset of the wheels.  If you add a spacer you will decrease the negative offset.

  When this happens you will have a feeling of more stability but your steering wheel will have less feedback.

 But its much more than that. When you change the offsets you  change the scrub radius which can make a profound difference on how the car handles because it changes the geometry of the whole suspension including the spring rates. It is one of those modifications that can radically change the way the car feels depending on how much or how little so you need to carefully consider.

 Before I would add a spacer I would work on other things since you are using stock sizes it shouldn't be this bad for you and it could just be an alignment issue.



Yeah but the front wheel is 7" with 38 offset vs  6" 45 offset. Meaning its spaced out around 12 mm. I want to fix this first as I have good alignment. -2.2 all around and 0.1 toe in rear/ 0 toe front.
If you want sharp turn in then more front toe out is necessary. I set mine at 0 when I first got the car and it was plain dull. Changed this to 1mm (0.09°) out each side, and it was much, much better. Now have it at 2mm (0.18°) out each side, and its so sharp. However this maybe to extreme for a road car, and will scrub the inside of the tyres.

Also I find the OE wheel offset doesn't help with feel and stability. Mine feels much more planted on aftermarket wheels with a 38ET, as it widens the axle track.

 That is true in that more negative does feel more stable but that is because if feels less responsive to every bump in the road with less feedback. 
 I like more responsiveness that the OE offsets provide even if it feels less stable because I think its stable enough but far more playful for the street especially at lower speeds making it fun to drive.
Title: Re: Anyone running a square set up on 15"?
Post by: Smithy on April 15, 2021, 15:56
Quote from: Dev on April 14, 2021, 00:37
Quote from: m1tch on April 13, 2021, 15:41I am running a square setup in terms of wheels but running 195 front, 225 rear so same wheels, staggered tyres.

I thought square meant same width tires all around unless I am mistaken.   
  I know of double stager which is different tire width and different wheel hight. Or triple stagger which is different tire width, different wheel width and different wheel hight which is what the FL car has.


Sorry yes you're right. I have the same wheel size but different tyre sizes.
Title: Re: Anyone running a square set up on 15"?
Post by: Dev on April 15, 2021, 16:05
Quote from: Smithy on April 15, 2021, 15:56
Quote from: Dev on April 14, 2021, 00:37
Quote from: m1tch on April 13, 2021, 15:41I am running a square setup in terms of wheels but running 195 front, 225 rear so same wheels, staggered tyres.

I thought square meant same width tires all around unless I am mistaken.   
  I know of double stager which is different tire width and different wheel hight. Or triple stagger which is different tire width, different wheel width and different wheel hight which is what the FL car has.


Sorry yes you're right. I have the same wheel size but different tyre sizes.

I actually asked because I thought maybe it was something new that I was not aware of.
Title: Re: Anyone running a square set up on 15"?
Post by: Smithy on May 4, 2021, 11:01
I'm very pleased with my wheel set up now and It handles even better than before. I bought it with 17" rear and 16" front OEM wheels and it felt really planted in the bends. moving to 15" with staggered tyre sizes it feels like it picks up quicker (they are 2kgish a wheel lighter to start with) and it corners really well. It does however feel lighter at the front end in a straight line at higher legal speeds?
I have gone for the same PSI as before 26 front and 32 rear, is that correct?
Title: Re: Anyone running a square set up on 15"?
Post by: Ardent on May 4, 2021, 11:56
Generally yes.
But specific tyre info would be required say properly.
Are they standard or XL tyres?
Title: Re: Anyone running a square set up on 15"?
Post by: Chilli Girl on May 4, 2021, 13:21
Yep, mine were 26 fr, 32 r but they were stock facelift sizes, 15 fr,16 r.
Title: Re: Anyone running a square set up on 15"?
Post by: Dev on May 4, 2021, 14:01
What is the load rating on the tires?



Title: Re: Anyone running a square set up on 15"?
Post by: jvanzyl on May 4, 2021, 19:17
Erm you didn't have oem wheels... oem FL wheels are 16 rear and 15 front.
Please do share a pic.
Glad you're doing better anyway.
Title: Re: Anyone running a square set up on 15"?
Post by: Joesson on May 4, 2021, 19:50
Quote from: jvanzyl on May  4, 2021, 19:17Erm you didn't have oem wheels... oem FL wheels are 16 rear and 15 front.
Please do share a pic.
Glad you're doing better anyway.

I thought that until recently when I noticed this:

https://www.mr2roc.org/forum/index.php?msg=851547

 I mentioned the 5 wheel nuts and the Roll Bar but neglected to mention the 17 inch wheel " options" that I guess makes them Optional OE
Title: Re: Anyone running a square set up on 15"?
Post by: Smithy on May 5, 2021, 11:57
I will get a better picture tonight but this is my car as I bought it. 17" rear and 16" front.
Title: Re: Anyone running a square set up on 15"?
Post by: AdamR28 on May 5, 2021, 13:53
I'm running square on 14s. All good.
Title: Re: Anyone running a square set up on 15"?
Post by: Petrus on May 5, 2021, 14:09
On a tráck car Adam. Just a detail, I know, but still ;-)
Title: Re: Anyone running a square set up on 15"?
Post by: Dev on May 5, 2021, 15:53
Quote from: Smithy on May  5, 2021, 11:57I will get a better picture tonight but this is my car as I bought it. 17" rear and 16" front.


 That is a FL car with 15/16 wheels.  Oddly enough the rear 16" OEM wheels is very heavy compared to the 15" wheels for the PFL and a good number of  17" aftermarket wheels.
 
Title: Re: Anyone running a square set up on 15"?
Post by: 1979scotte on May 5, 2021, 20:30
Quote from: AdamR28 on May  5, 2021, 13:53I'm running square on 14s. All good.

On track with no weight
Title: Re: Anyone running a square set up on 15"?
Post by: AdamR28 on May 6, 2021, 07:36
No reason it wouldn't work just fine on the road, though.
Title: Re: Anyone running a square set up on 15"?
Post by: Petrus on May 6, 2021, 08:37
Quote from: AdamR28 on May  6, 2021, 07:36No reason it wouldn't work just fine on the road, though.

Ground clearance?

That observed it is thé easiest solution to a bit lower gearing and the lightest wheels.
Title: Re: Anyone running a square set up on 15"?
Post by: AdamR28 on May 6, 2021, 08:53
Fair point.

Though assuming 185/60R14 tyres, a common size for 14" wheels, that would only drop ride height low single figures of mm.
Title: Re: Anyone running a square set up on 15"?
Post by: Petrus on May 6, 2021, 09:25
Quote from: AdamR28 on May  6, 2021, 08:53Fair point.

Though assuming 185/60R14 tyres, a common size for 14" wheels, that would only drop ride height low single figures of mm.

Aye, but I don´t live on a smooth track but at the end of a dirt track with green strip in the middle :-)
When I bought the car I could not get home. Needed to kleave it at the bridge and do a week of hard shovelling hardpack to fill in the track a bit. Also cropping the green short a dozen times/year.
At its very, VÉRY best it is

(https://myalbum.com/photo/Z0aKDDr8mspd/1k0.jpg)

and nów it it 20-25 mm lower on Sportivo kit :-O

Also getting on/off tarmac is more often than not a 10 cm. step. About half the time the parking is an unbuilt barren plot hardly suited for any road car.
Never mind getting in/out underground parking lots crossing the ideal.
Title: Re: Anyone running a square set up on 15"?
Post by: AdamR28 on May 6, 2021, 11:03
Don't lower your car then, simples ;)
Title: Re: Anyone running a square set up on 15"?
Post by: 1979scotte on May 6, 2021, 11:57
Quote from: AdamR28 on May  6, 2021, 11:03Don't lower your car then, simples ;)

Why didn't I think of that?
Title: Re: Anyone running a square set up on 15"?
Post by: Petrus on May 6, 2021, 12:09
Quote from: AdamR28 on May  6, 2021, 11:03Don't lower your car then, simples ;)

Yup.

Real world dictating.