In defense of 14" rims

[JFENG]

I did a 25 mile drive today my yet-to-be restored E9 (3.0cs w a tired motor, 5spd OD).

As the first drive of the season, for a somewhat neglected coupe, it was not without trouble. First, I noticed the windows didn't work unless I had the drivers door open (p-door no effect). I haven't traced the fault yet, but clearly hat door switch is providing the ground for the window relay (I hear it click when the interior light goes on. For now I open the door to adjust the windows (easy to do secondary roads). Don't you love 1970's era electrical systems?

Next, I pull put of my driveway and notice the electronic low-amp flasher relay I put in 2 years ago is giving me three blinks for a momentary flick of the turn signal lever. Just like my modern BMW, but I'll bet it's a sign of something else getting ready to go bad.

TIRES: Finally, I got on the road and did about 14 miles on narrow twisty New England back roads. Half of the drive was on second and third gear roads (30-65mph). This car has older Yokohama 195/70-14 Avid tires (7-8 years old?). Despite the modest tire setup, I actually never found myself wanting more grip. The car handled every corner smoothly and with minimal under steer The tall sidewalls took the edge off all but the worst bumps and potholes. It was a lovely vintage GT motoring experience. Even the chassis flex didn't bother me as it is in line with pillarless coupes of the day and all part of the 'charm' of the E9.

To be honest, I think going significantly faster (or driving closer to the car's max potential) would be driving recklessly given that I was on public roads.

I have a set of BBS RS 16" rims that I intend to outfit with extreme performance tires. But today's drive reminded me to respect those that stay with 14" rims. The only place where I think I can legitimately criticize the 195/70-14's is in regard to braking grip. In fact, its tempting to stay with a smooth riding 14" setup for the street and save the polished 16's with gumballs just for track days and C&C events.

FWIW: I run 36psi up front and 34psi in the back (cold). I have Carl Nelson's lower springs, Bilstein sport shocks and the bigger ST sway bars. All the bushings are stock rubber except for the anti-sway bar mounts and end-links (poly). The rear sway bar is set to the middle hole to dial out some under steer. I can't say enough good things about this inexpensive yet effective setup. For those of you still on the stock USA setup, this suspension conversion should be high on your list to do.

John

 

[Stevehose]

I agree, the extra tire on the 14's smooths out the harshness from the lowering springs and Bilstein's. My car still handles well enough for me (I am not an aggressive driver but will go as fast as the fastest car on the interstate) and I love the period look. I run 205's so perhaps that might help your braking concerns when you replace those 8 year old tires

 

[CookeD]

Your fault with the window may be with the interior light switch that is in the A-pillar. Take it out and make sure it's plugged in, and you can clean it and lubricate it to debug.

 

[adawil2002]

Have the same suspension set up except stock springs in the rear. The sway bars make all the difference.

 

[E911]

The look of 14 x 7 wheels on a lowered Coupe is pretty hard to beat... I just opted for them over 16" staggered on my latest project despite the lack of tire choices. And as Steve says, really takes the edge off the standard suspension upgrades that can make for a not so "compliant" ride.

 

[nashvillecat]

Fourteen inch rims do not need defending, it's the rubber choices that do. I recall fitting the OEM fourteen inch rims with Michelin XWX tires that offered excellent grip. But not for long. (I vaguely recall a treadwear rating of "50" despite 1985-NYT article that mentions "100.") But for the cost and anticipated frequent replacement, I would probably still be using them.

One treadwear-ratings point is equivalent to approximately 200 miles of driving. Thus, a tire with a treadwear rating of 100 should get 20,000 miles.

The ratings also showed all tire companies had good and poor mileage performers - including Michelin's XWX at a 100 rating or 20,000 miles.

http://www.nytimes.com/1985/07/30/us/michelin-tire-rated-as-best-in-federal-testing-program.html

Treadwear grade
A government-required number that indicates a tire’s expected wear. A grade of 300 denotes a tire that will wear three times as well as a tire graded 100. But the numbers are assigned by tire manufacturers, not an independent third party.https://www.consumerreports.org/cro/magazine/2015/09/the-truth-about-tire-treadwear/index.htm

 

[WISE9UY]

This is a great quick message and agree when I got my E9 on the 14's with stock suspension it was a very nice cohesive package. I since went down the path of craving larger more modern wheels up to having purchased (gasp) 18" staggered BBS mesh wheels, which I never even fitted tires to, then down to 17" and subsequently believe 16" is more than enough. Happy motoring

 

[shanon]

+1 for 14"s. For fun, you might experiment with the rear sway set-ups. My brother and I have found they are faster with the rear sway completely disconnected. Everybody's tastes are different, but they stick better when they can roll a bit.

 

[JFENG]

I did pull the light switch in the a pillar and noticed that when I pushed or released the contact the window motor relay clicked. Pulled and cleaned the contacts but that didn't do anything because the light switch was already working correctly. The problem is the window relay ground is apparently no good and somehow getting grounded via the a pillar switch. I suspect a loose wire up under the dash where the relays are located.

Wheels: I believe you can find BBS RS rims in a 15" diameter, which might be a sweet-spot between good tire avail and a good ride.

 

[HB Chris]

If it clicks it's definitely working.

 

[Mal CSL 3.0]

I have a set of 14" rims, currently have 205/60/14 tyres. Just a warning I wouldn't recommend this size as they look too undersized for the car.
195/70 as per factory spec probably much better.

 

[Arde]

I have Michellins on 14'' rims, Bilsteins, and ST-sway bars. I am happy with the handling. The springs are stock and I do not know if they were ever replaced.

How about ratholing on springs getting softer with time? I can get us started:

- Of course they wear down, have you heard about metal fatigue?
* Nope, a soldier wearing a shiny uniform? Have you heard that "Hope Springs Eternal"? What part of Spring's eternal you do not get. E-ternal.
- Shocks dampen, but ride height is determined by springs, if the car height drops over time voila, the springs got softer.
* No they got compressed, now you have lowering springs but the rate may be the same. A free upgrade to lowering springs! Like wine, springs get better with time.
- So you are saying spring harden over time? That is absurd.
* Ok call Don, ask him.
- I did, long answer about if you have not tuned a 12 carburetor Ferrari while crossing Death Valley barefoot screaming in German to W+N to refund a damn made in Turkey guibo you cannot understand springs.

 

[E911]

I have a set of 14" rims, currently have 205/60/14 tyres. Just a warning I wouldn't recommend this size as they look too undersized for the car.
195/70 as per factory spec probably much better.

Agree, try 225/60- they look great on 14 x 7 wheels and they really fill out the wells.

 

[pmansson]

14" with XWX is the best in my view. I have it on most of them. 3 have the 16" with modern low profile tyres. A bit better on hard cornering, but too rough when driving normally on less than perfect roads.
Personal taste on what looks best, but I find the 14" and lowered suspension is very atteactive. And period correct incl the fat tyres with its fantastic thread. My oldest are 10 yrs and unnoticeable wear. I never leave the car in the sun for fery long. Rubber is still almost like new.

 

[Ohmess]

Wheels: I believe you can find BBS RS rims in a 15" diameter, which might be a sweet-spot between good tire avail and a good ride.

I have 15s on my car, and like them a lot. In addition to making the ride more compliant, I think the e9 looks better with a fatter sidewall.

 

[aearch]

bf goodrich ta radials are my favorite tread and exterior look.

 

[rsporsche]

my favorite for 14" is the pirelli cn-36 that Stevehose has on his polaris coupe with stock wheels. yes, they are more expensive than the goodrich, but a whole lot better tire. totally equivalent to the XWX for less money ... and period correct. i would buy them for my 15" wheels, but they are almost 50% more than the 14" - 276 gbp vs 199.

 

[Stevehose]

4 months in and I still get some drool in the corner of my mouth everytime I look at them.

 

[Stan]

bf goodrich ta radials are my favorite tread and exterior look.

I went with the BF turned inside out and painted the raised white letters black,'
225/60/14 is tough to find and these cost a lot less

 

[Koopman]

I did a 25 mile drive today my yet-to-be restored E9 (3.0cs w a tired motor, 5spd OD).

As the first drive of the season, for a somewhat neglected coupe, it was not without trouble. First, I noticed the windows didn't work unless I had the drivers door open (p-door no effect). I haven't traced the fault yet, but clearly hat door switch is providing the ground for the window relay (I hear it click when the interior light goes on. For now I open the door to adjust the windows (easy to do secondary roads). Don't you love 1970's era electrical systems?

Next, I pull put of my driveway and notice the electronic low-amp flasher relay I put in 2 years ago is giving me three blinks for a momentary flick of the turn signal lever. Just like my modern BMW, but I'll bet it's a sign of something else getting ready to go bad.

TIRES: Finally, I got on the road and did about 14 miles on narrow twisty New England back roads. Half of the drive was on second and third gear roads (30-65mph). This car has older Yokohama 195/70-14 Avid tires (7-8 years old?). Despite the modest tire setup, I actually never found myself wanting more grip. The car handled every corner smoothly and with minimal under steer The tall sidewalls took the edge off all but the worst bumps and potholes. It was a lovely vintage GT motoring experience. Even the chassis flex didn't bother me as it is in line with pillarless coupes of the day and all part of the 'charm' of the E9.

To be honest, I think going significantly faster (or driving closer to the car's max potential) would be driving recklessly given that I was on public roads.

I have a set of BBS RS 16" rims that I intend to outfit with extreme performance tires. But today's drive reminded me to respect those that stay with 14" rims. The only place where I think I can legitimately criticize the 195/70-14's is in regard to braking grip. In fact, its tempting to stay with a smooth riding 14" setup for the street and save the polished 16's with gumballs just for track days and C&C events.

FWIW: I run 36psi up front and 34psi in the back (cold). I have Carl Nelson's lower springs, Bilstein sport shocks and the bigger ST sway bars. All the bushings are stock rubber except for the anti-sway bar mounts and end-links (poly). The rear sway bar is set to the middle hole to dial out some under steer. I can't say enough good things about this inexpensive yet effective setup. For those of you still on the stock USA setup, this suspension conversion should be high on your list to do.

John

Hi John.
I have a nearly new set of 205-70-14 Blizzard tires on Mercedes rims if you can use them. Of course not the rims.
Thanks
Harry