[MattGM]

Why?

I just googled it and saw an answer on quota haha
It made sense tho, that larger rear track width would prevent rear weight transfer more then in the front making it more likely for the front to lose traction. I’m not a physicist but that sounds right in my head.

 

[Petrus]

Another thing I'm a little confused about is offset and how spacers work and when they are needed.

Spacers are used to reduce the offset; to put the wheels further out. It is a shortcut to wheels with the desired offset and comes with serious downsides.
One being that they in effect shorten the studs. Hence they are availeble with their own studs. You bolt them to the hub and then the wheel to the spacer.
It does not need a rocket scientist to get that this is suboptimal and that it also adds unsprung weight which is só noticeable on the itsybitsy Spyder.
Best shun them if a well handling car is the goal. If looks is the priority, then all rules change. You can go 17, 18" diameter, stretching rubber on a 10J , even 10 or more degrees negative camber!

 

[Petrus]

I just googled it and saw an answer on quota haha
It made sense tho, that larger rear track width would prevent rear weight transfer more then in the front making it more likely for the front to lose traction. I’m not a physicist but that sounds right in my head.

The question is ´Why?´

Do you think the car needs to be more understeered? Thát is the crux for handling changes.

 

[phattires]

Thanks for all the advice. After looking around a bit more I think I’m going to go with 15x7 35 offset in the front and 16x8 38 offset in the rear. Unsure about tires at the moment.

225/45 is perfect for the back with that offset , the fronts are where you'll have to compromise . If you are on lowering springs or plan to go lower you'll have to stay smaller than a 205/50 or you will get a slight rub on a hard corner .

 

[beachbum]

While I probably should just go with OEM my stubbornness is getting the better of me.

I think I’m gonna go with 15x7 with 41 offset in the front to keep steering hopefully similar, and 16x8 with 38 offset in the rear. My understanding also is a larger track width in the rear then the front promotes understeer over oversteer which seems like a positive too.

Tire recommendations for those sizes would be greatly appreciated but y’all have already helped a ton.

The 16" are going to be hard to find with a matching 15" front. Common sizes are 195/50 -15 front and something like a 205/45-16 rear, although a 8" rim may be too wide for that size. Most manufactures recommend a 7" rim for 205/45-16. You do have some brand options in those sizes.

We run 16" all around and are going to 195/45-16 front and 205/45-16 rear, both on 7" rims

 

[cosmin]

I don't know why you think a wider wheel base has an adverse effect on handling.

 

[carlbecker]

Man it's getting pretty deep in here , I call BS if you're saying you can tell a 35 offset from a 45 offset with the same size tire . I'd agree you can tell tire size being different but not those two offsets . !85/55's suck .

Call it what you like, there is a difference, a bit nervousness added. I suspect the difference is related to the steering inclination angle change but I am not an engineer. Then again I am not one for big changes from the original design as once again I am not an engineer. Of course I can also notice the difference between Koni shocks and OEM KYB, BridgeStone RE-040, RE-11, Dunlop 102, Dunlop ZII, Kumho PA-31, PS-31 tires. I can't tell the difference of 2 psi in the tires while street driving. I can tell the difference in small toe changes ft or rear and the door latch brace difference is noticeable. I keep camber settings at OEM center spec. Some of the bracing I have added didn't seem to make much difference. Amazingly I am not the most perceptive of people.

The weight added by spacers is nothing if longer studs are required for new wheels. I had to replace the studs when I installed the 15" Volk ce28n wheels costing several grams. Volks are Eight lbs each on the front and 8.5 each on the rear, weighed on my scale. Overall a good weight reduction.

I enjoy 185/55 or 195/55 very much. If the Dunlop ZIII where available in 185/55 I would use them. I prefer "in the middle" tire to wheel width matching.

 

[Petrus]

I suspect the difference is related to the steering inclination angle change but I am not an engineer.

It is simpler: The further out the wheel, the larger the torque reaction from differences in forces from the road.
This is quite common knowledge as to load on the bearings but it is exactly the same for the force on the steering mechanism.
From 45 to 35 may only be 10 mm but it is also a near 30% increase in arm length. Not a problem for the bearings but in the steering you cán notice that.

So yes you will notice it as more ´nervous´.
Hence also more sensitive to tramlining.

The upside is that it gives more feed back thus feel in the steering wheel. Delete the p.a.s. and you can most definitely notice the difference.


Aaaaaaanyway; it goes to show that appearantly small changes can most definitely have significant effects..

 

[Petrus]

Amazingly I am not the most perceptive of people.

There is a very interesting aspect to that. We humans are more sensitive to some forces than to others.
We are per example not very sensitive in ´measuring´ a force but more sensitive in changes in force and even more in changes in direction of forces.
I terms of steering you will hardly notice the force needed to keep the line through a bend. You will notice a slight extra effort or ease more. A farfár smaller vibration = alternating force, because of a slight wheel balance you will définitely pick up.

Same phenomena applies to your bum and head.

Also take into account the seats. The OEM seats will communicate forces less clearly to your body than bucket seats.

Now, there is a sneaky factor in the seat support too: The better your body is supported the less you need to brace your body and no matter how good you are at that the less you will ´hold on´ to the steering wheel. The less you are ´holding on´ the more noticeable changes in the outside forces on that steering wheel.

I lóve my unpadded buckets

 

[FormInFunction]

Don't pick wheels until you confirm the tire choices will fit your needs

 

[beachbum]

Don't pick wheels until you confirm the tire choices will fit your needs

Best advice of the day

 

[phattires]

Don't pick wheels until you confirm the tire choices will fit your needs

Which came first .... the chicken or the egg ? lol

 

[carlbecker]

Don't pick wheels until you confirm the tire choices will fit your needs

best advice of the thread.

 

[Petrus]

Which came first .... the chicken or the egg ? lol

The dinosaur.

As I wrote; get experience with the car first; dríve it FIRST ffs.

If it is about looks.... well; by all means go 17", slam it, stance it; weigh it down with a bolt on look faster kit. It will still be qicker than the average driver anyway

 

[MattGM]

225/45 is perfect for the back with that offset , the fronts are where you'll have to compromise . If you are on lowering springs or plan to go lower you'll have to stay smaller than a 205/50 or you will get a slight rub on a hard corner .

So if I were to try and keep a 225/45/16 in the rear is there any tire option that will allow me to keep it staggered with 15s in front? I don't plan on lowering the car as of right now as roads are pretty horrible around New England so 205s should be fine hopefully.
The only tire options I see are Toyo PROXES R888R which are Track only, so that's not a solution as this is primarily a road car. Are there any negatives to going either 16s all around (or 15s all around if that is preferred for any reason).

Edit: After looking around a bit more Toyo Proxies R1R come 205/45/16 and 225/45/16. Seems like that's the closest I'm going to be able to get to running 205s in the front and 225s in the rear on street tires. So I guess that comes back to the question: Is there any negatives to running the same diameter tires in both front in rear? (the only reason I ask is I'd imagine there is a reason they come OEM with diff diameters)

 

[carlbecker]

2000 to 2002 spyder had 15" rims ft and rr. 6" wide ft and 6.5 wide rear. 2003 up had 16" rear rims same front. Tire dia and width are you parameters for fitment. Offset for suspension geometry compliance.
"Is there any negatives to running the same diameter tires in both front in rear? " Aspect ratio changes, given the overall tire diameter is constant, and it changes with diameter of rim and width of tire.

 

[scotched]

@MattGM

Figure out what's more important to you when it comes to wheels/tires. Looks and handling don't always go together and some of the "best" wheel/tire combos are downright ugly.

+36 looks pretty good on this car. I run 15x8 +36 square on 205 tires. I went through 2 other configurations before I settled on this. Might take a few tries before you're happy. Get the best tires you can afford.

 

[Dustin110]

@MattGM

Figure out what's more important to you when it comes to wheels/tires. Looks and handling don't always go together and some of the "best" wheel/tire combos are downright ugly.

+36 looks pretty good on this car. I run 15x8 +36 square on 205 tires. I went through 2 other configurations before I settled on this. Might take a few tries before you're happy. Get the best tires you can afford.

Are you running 205/50/15? Do you have any pictures?

 

[phattires]

So if I were to try and keep a 225/45/16 in the rear is there any tire option that will allow me to keep it staggered with 15s in front? I don't plan on lowering the car as of right now as roads are pretty horrible around New England so 205s should be fine hopefully.
The only tire options I see are Toyo PROXES R888R which are Track only, so that's not a solution as this is primarily a road car. Are there any negatives to going either 16s all around (or 15s all around if that is preferred for any reason).

Edit: After looking around a bit more Toyo Proxies R1R come 205/45/16 and 225/45/16. Seems like that's the closest I'm going to be able to get to running 205s in the front and 225s in the rear on street tires. So I guess that comes back to the question: Is there any negatives to running the same diameter tires in both front in rear? (the only reason I ask is I'd imagine there is a reason they come OEM with diff diameters)

As you can see everyone likes something different , a lot has to do with how and where you drive and what you like .

Other than the 205/45 people run 205/50, 195/45 , 195/50 195/55 , 185/55 . Some like the same size all around so they can rotate . I think having the front and rear the same diameter makes it easier to buy tires . R1R's has some good sizes but seem expensive and are pretty soft so you won't get many miles out of them . I'm going to try some federal evoluzion st-1 can't say how they are yet but they have 215/45/16 and 205/45/16 and are about a $100 per . Mine are a different size cause they're are for a widebody . You also might want to look at BFGoodrich comp 2's ,alot of people seem to like them but don't know they're sizes right off .

 

[FormInFunction]

So if I were to try and keep a 225/45/16 in the rear is there any tire option that will allow me to keep it staggered with 15s in front? I don't plan on lowering the car as of right now as roads are pretty horrible around New England so 205s should be fine hopefully.
The only tire options I see are Toyo PROXES R888R which are Track only, so that's not a solution as this is primarily a road car. Are there any negatives to going either 16s all around (or 15s all around if that is preferred for any reason).

Edit: After looking around a bit more Toyo Proxies R1R come 205/45/16 and 225/45/16. Seems like that's the closest I'm going to be able to get to running 205s in the front and 225s in the rear on street tires. So I guess that comes back to the question: Is there any negatives to running the same diameter tires in both front in rear? (the only reason I ask is I'd imagine there is a reason they come OEM with diff diameters)

Perhaps I'm a bit confused...when you say the same diameter are you referring to the tire diameter or the wheel diameter? FWIW I've always used OEM wheels (16 inch Enkei's very briefly) & the car handles incredibly well. Definitely not aggressive in appearance but with the OEM wheel size good rubber is cheap & options are plentiful for all driving situations. Either way, as was stated ppl have preferences based off of every variable of their setup from the wheels & tires to the suspension, strut/sway bars & even their alignment. Every suggestion should be taken with a grain of salt based on how your setup as a whole varies from someone else's (even with the same wheels & tires).

I would reiterate again that you should pick the wheels based off the available tire options (UHPS/UHPAS/track tires) for what you plan to use the car for. Personally, only having 1 high performance summer or all season tire available wouldn't be acceptable for me but YMMV