Tire wheel question

[kickster]

Hi
I have a 1988 Jetta GL. currently I am using
205 50 15 Toyo FZ4 with OEM 15" Passat rims.
Tire and wheel weight is about 39lb

I raced on Cayuga and some SoloII events. The handling is not too bad, however, I would like to
maximize my traction for next season.

I am thinking of reducing rotational mass and radius as much as I can. In order to do this I have few choices

1- Down size to BBS Miata wheels (OEM) they weigh 9lb
and use Toyo 195 45 14 T1-S. in total they weigh
24lb The weight drops by 15lb (total of 60lb!!)
and It will lower the gear ratio and lowers the center of gravity by 1.1" The draw back is that I am using smaller tire and rim size

2- Use 15" rota subzero rims (weigh 11.5 lb) plus Toyo t1-S 195 45 15. The rim/tire weight will be 27lb, however the gear ratio will not change by much.


which option will be best for my car?

Thanks in advance.

[DECH_92]

Smile
I would put on Kumho 225-45-15 same dia. on 7 or 7.5 rim...
Pedal to the floor , go around corners flat out.
Your probably get alot of answers .

[tanney]

Go with the down size option.

You hp is low enough that the gearing and torque will be better and the rotational mass will be less which means even more torque. Go with 205/50 or 60's though.

That's coming from someone who runs the snot out of under-horsepowered cars with small wheels.

[ice/solo racer]

As a guy racing on street tires(falken azenis)and lucky enough to win the BSS class title,I would suggest running r-tires as the 2% street tire bonus leaves you at a disadvantage.I'm glad I tried the street tires and the falkens are truly a great tire but I'm with the other replyers,go light rims and smaller dia.
I'm not sure about running 225's on a light car as they may not heat up and stick as well as a 205?.I'm facing the same thing for my corolla for next season(of course my wife warms my tires up for me!)

[kickster]

Well, 225 tire will not fit on A2 jetta. It is too big. Beside I want to lower the weight.

More opinions please.

[ice/solo racer]

I forgot the tight fit with VW's,I would look at keeping your 15's or what ever you want on the street and going with something like a 215-50-13 r-coumpound for the shorter tire.That size should be doable with careful rim offset/spacer choices.I woundn't use a spacer on the street but for auto x only should have no problems if check lugs every run.
Check with Per at grassroots motorsports mag.,he has tons off VW info.

[Dave]

for racing purposes, you always want to go with the smallest diameter and lightest rims you can fit on your car. Limiting rotational mass is very important and as Wes mentioned smaller diameter rims also effectively shortens up each gear thereby allowing you to get the power to the ground faster. Fast is good :) However, wheel width is also very important, since a wider rim will stretch out the tire and give you a more consistent contact patch. You haven't mentioned how wide the rims are that you're considering, but definitely take this into consideration along with wheel diameter and wheel weight. You want the best possible combination of these three variables for the fastest set-up.

[rpr]

I have a set of light 13x5.5 Momo rims in the For Sale forum...hint hint...

[RedRabbit Racer]

I've been racing VW's for some time and I'd say the most important thing is to lose the 15" passat rims. they weigh a ton.

In my experience there is not much difference between the 205/50-15, 195/55-14, 205/55-14, 205/60-13 or 215/50-13 sizes given the same brand and compound. the first three tend to fit better in the wheel wells without spacers. I presume you don't have the 256mm front brakes or the 13's probably won't fit.

There is not much difference in diameter, the 195/55-14 being slightly smaller but not terribly noticeable. When you drop down to something like 20x8x13 with a big difference, you can find shift points moving around, frequently to undesireable places like the middle of corners, too close to braking points etc.

While it is not always cheap or practical, gearing should be changed in the transmission (use a 4K or 2H box).

It pretty hard to beat the 205/50-15. You just don't need a huge tire to support a static weight of 275 lbs per side (like the back of my Rabbit).

[kickster]

I agree, the passar rims with 205 50 15 weigh 40lb
I was thinking of getting 15" rota rims with Toyo T1 195 45 15. This is a very light set up.
Wheel is 11.8 lb and tire is 16 lb total of 27.8
thats about 12lb less

I have 9.4" brakes so 13" should fit.
My concern with 13" is tire size. I want use a street tire with very low profile.

[B18C5]

Weight isn't necessarily the biggest deal to deal with when you're dealing with wheels and tires. That being said, those 15s are probably a bit heavy. Gearing is nice to change too, but your speedo will be pretty messed with smaller tires, and who knows if the gearing change will actually benefit you on the tracks that you will be running on until after you've run on them?

There's nothing wrong with getting a set of nice tires for your 15" rims. Something like a 195/55/15 set of Bridgestone RE010s would rock as a street/track tire. I have heard of them chunking with serious lapping day abuse, but what street tire won't. I never had any problems with them and your car is a lot lighter. They're the OE tire on the Type R. They're really good.

If it were me I would go for a set of 14x7" wheels. Tire Rack used to sell Borbet Type Ts, which were relatively light. It looks like they still have them. They look to be the cheapest most readily available 14x7" wheel. I would value wheel width more than weight. Saving weight is great, but having more width will be more advantageous. A 14x7" wheel is the perfect tradeoff. Another good thing about a smaller wheel is the rotational mass is closer to the centre, so even though a wheel may weigh more it effectively isn't.

A 13x7" rim would be great for running that odd 215/50 size, which is super if it will fit. That would be your best choice for your car the way it is right now. But I still think that a 14x7" wheel would be a better choice planning for the future. That way you're still able to upgrade your brakes when you want (need) the extra diameter. Eventually you might want to get some of those fender flares and fit some 225/50 14s. Worst comes to worst you might need some spacers and longer nut/lug/bolt thigies (whatever you call those).

Coles notes: For next year I would just run 195/55 15 Bridgestone RE010s on the Passat rims. Be sure to mount them after the temperature rises again since they're horrible when the ambient temperature is under 0º. Then I would see if the car needs more brakes by lapping. Depending on plans for the car I would then get a set of 13 or 14x7" wheels with R compounds.

Hrm. I think I got excited...