Notices
964 Turbo Forum 1989-1994

RH 3.6 Tire Sizing

Thread Tools
 
Search this Thread
 
Old 02-07-2022, 12:54 AM
  #16  
revolution993
Rennlist Member
 
revolution993's Avatar
 
Join Date: Feb 2006
Location: Toronto
Posts: 1,561
Received 100 Likes on 67 Posts
Default

Originally Posted by bweSteve
Excellent. Your car is beautiful. Would love to hang out sometime & grab a beer.

To further the eye candy here on your thread,... here's a few pics of my car from the 2017 Amelia Island Werks Reunion. I took 3rd place that day (~ 20 cars in our class).



what size and offset are you running? Looks similiar to mine.
Old 02-07-2022, 09:36 AM
  #17  
Metal Guru
Rennlist Member
 
Metal Guru's Avatar
 
Join Date: Apr 2007
Location: Beverly Hills, Mi.
Posts: 4,521
Received 429 Likes on 309 Posts
Default

Originally Posted by bweSteve
Keep in mind that most folks on public forums, and at the Cars & Coffee, love to have bragging rights on rear tire size. I've definitely heard it said (with pride) at my local C&C,.. they're running a 295, or 285. It sounds great to say,... but in reality the manufacturer can build a 265 & make it with such wide section & tread width that it can actually look as wide as a 285. .... plus, when you're actually driving the car spiritedly, you'll want the smaller, stiffer sidewall, to give you that tight feeling in the corners.
Geez, people barley know what my car is, let alone ask about tire width at C&C.
I'll provide another point of view to the discussion. IMO, putting a small tire on a wide wheel makes said tire look even smaller. When I bought my car, having stock tire sizes gave them a stretched look that I don't prefer. To me it's nothing more than a modern automotive fashion statement. To my eye, it accentuates the fact the the tread width is smaller than the rim width.
Sure, you get more linear response (less hysteresis) with a stiffer sidewall but the only guy to who that would matter in the 965 world just sold his car
I don't have canyons to carve in Michigan so I'm going to forgo that last 1% of snappy response.
Going with the 235's and 295's like I did give the sidewall and rim pretty much a line to line relationship. No bulging over the rim (I don't care for that look either), but you don't get that anyway with low profile tires. The important thing is that the tread width and rim width are very close.
In fact, I've bought a new set of Speedlines and I've reverted the rear width back to 10 inches. I didn't care for the look of a 295 on a 10-3/4 rim; it had that stretched look and didn't match up with the front.
So to each his own. The important thing is to know what you like, I suppose.

Old 02-07-2022, 11:57 AM
  #18  
bweSteve
Rennlist Member
 
bweSteve's Avatar
 
Join Date: Mar 2015
Location: Baltimore Maryland
Posts: 4,085
Received 1,049 Likes on 666 Posts
Default

Originally Posted by revolution993
what size and offset are you running? Looks similiar to mine.
I kept the same Front size & offset that I have been running for 20 yrs,.... and only changed the Rear offset & width.

So here is my new setup...

Front ET46 ... 8.5 x 18
Rear ET59 ... 10.5 x 18


Originally Posted by Metal Guru
Geez, people barley know what my car is, let alone ask about tire width at C&C.
I'll provide another point of view to the discussion. IMO, putting a small tire on a wide wheel makes said tire look even smaller. When I bought my car, having stock tire sizes gave them a stretched look that I don't prefer. To me it's nothing more than a modern automotive fashion statement. To my eye, it accentuates the fact the the tread width is smaller than the rim width.
Sure, you get more linear response (less hysteresis) with a stiffer sidewall but the only guy to who that would matter in the 965 world just sold his car https://www.youtube.com/watch?v=Zz7G...CollectingCars
I don't have canyons to carve in Michigan so I'm going to forgo that last 1% of snappy response.
Going with the 235's and 295's like I did give the sidewall and rim pretty much a line to line relationship. No bulging over the rim (I don't care for that look either), but you don't get that anyway with low profile tires. The important thing is that the tread width and rim width are very close.
In fact, I've bought a new set of Speedlines and I've reverted the rear width back to 10 inches. I didn't care for the look of a 295 on a 10-3/4 rim; it had that stretched look and didn't match up with the front.
So to each his own. The important thing is to know what you like, I suppose.
The C&C people down here are very astute, and even the younger generations are keenly aware since they seem to love so much negative camber around here. And we actually have more 993 owners around here, than 964, so the discussions do occur.

For me, the BIGGEST improvement in adding a half inch to the width of my rear rim (going to 10.5") as well as changing the offset to move the entire rim deeper into my wheel well,... was that it allowed the very large PS4S 285/30 to fill the un-used portion of space between the lower control arm & the tire shoulder (in the lower front backside). As I'm sure all of you guys know, that spot is the location where your wide tires are closest to anything that it would hit (if you went too wide).
So for me, filling that un-used space on the backside would allow me to stuff a much wider tire on the car. So yea, it allowed that massive section width in the PS4S 285/30 to have the perfect amount of bulge -vs- stretch.

Before I arrived at this conclusion, believe me I tried. I first mounted that new tire on my old 10" ET54, and it definitely had way too much bulge (it literally looked like a old muscle car bulge). And to be honest, even the 10.5" brings the tire in some, but it is still no where near being called "stretched". If anything, for that specific tire, a 11" rim would still be even better, and still not be stretched. THAT is how wide the section width is on that tire. seriously, that damn thing is massive.

Also keep in mind that my goal was to MATCH the amount of bulge -vs- stretch, between the front & rear. The 225/40 on the 8.5" in the front, has a certain amount of stretch look to it,... so having the rear contain too much bulge just looked really weird to me.
Old 02-12-2022, 12:39 AM
  #19  
revolution993
Rennlist Member
 
revolution993's Avatar
 
Join Date: Feb 2006
Location: Toronto
Posts: 1,561
Received 100 Likes on 67 Posts
Default

Originally Posted by bweSteve
I kept the same Front size & offset that I have been running for 20 yrs,.... and only changed the Rear offset & width.

So here is my new setup...

Front ET46 ... 8.5 x 18
Rear ET59 ... 10.5 x 18




The C&C people down here are very astute, and even the younger generations are keenly aware since they seem to love so much negative camber around here. And we actually have more 993 owners around here, than 964, so the discussions do occur.

For me, the BIGGEST improvement in adding a half inch to the width of my rear rim (going to 10.5") as well as changing the offset to move the entire rim deeper into my wheel well,... was that it allowed the very large PS4S 285/30 to fill the un-used portion of space between the lower control arm & the tire shoulder (in the lower front backside). As I'm sure all of you guys know, that spot is the location where your wide tires are closest to anything that it would hit (if you went too wide).
So for me, filling that un-used space on the backside would allow me to stuff a much wider tire on the car. So yea, it allowed that massive section width in the PS4S 285/30 to have the perfect amount of bulge -vs- stretch.

Before I arrived at this conclusion, believe me I tried. I first mounted that new tire on my old 10" ET54, and it definitely had way too much bulge (it literally looked like a old muscle car bulge). And to be honest, even the 10.5" brings the tire in some, but it is still no where near being called "stretched". If anything, for that specific tire, a 11" rim would still be even better, and still not be stretched. THAT is how wide the section width is on that tire. seriously, that damn thing is massive.

Also keep in mind that my goal was to MATCH the amount of bulge -vs- stretch, between the front & rear. The 225/40 on the 8.5" in the front, has a certain amount of stretch look to it,... so having the rear contain too much bulge just looked really weird to me.
Thanks Steve , i think i will be ordering a new set of rears 10.5 ET59 .My back are 10 ET40 i can’t go wider then 265.
My goal is to achieve 285’s fir the rear.
The following users liked this post:
bweSteve (02-12-2022)
Old 02-16-2022, 06:59 PM
  #20  
LOMartin
Advanced
Thread Starter
 
LOMartin's Avatar
 
Join Date: Aug 2020
Location: South/East USA
Posts: 96
Received 43 Likes on 31 Posts
Default

Update:

The suspension will settle a little, I just lowered the lift.

​​​​​​I went with the setup that @bweSteve posted above, and it looks great. Now I’m thinking if I should push the front wheels out a bit?








Last edited by LOMartin; 02-16-2022 at 07:03 PM.
Old 02-16-2022, 08:08 PM
  #21  
bweSteve
Rennlist Member
 
bweSteve's Avatar
 
Join Date: Mar 2015
Location: Baltimore Maryland
Posts: 4,085
Received 1,049 Likes on 666 Posts
Default

I thought about that with mine too. Let me know what you do.

Anyone have experience with this Elephant Racing kit from Pelican?

https://www.pelicanparts.com/More_In...=0&SVSVSI=4389

Seems like a low cost kit to give some choices. no harm no foul if it isn't needed
Old 02-17-2022, 08:30 AM
  #22  
Metal Guru
Rennlist Member
 
Metal Guru's Avatar
 
Join Date: Apr 2007
Location: Beverly Hills, Mi.
Posts: 4,521
Received 429 Likes on 309 Posts
Default

I would try to stick with spacers that pilot on the hub and provide a pilot for the wheel, although these typically end up being thick.
This excludes most thin spacers.
The only thing I could find was H&R 6 mm spacers, which were thin enough allow a small amount protrusion of the hub pilot.
Old 02-20-2022, 09:46 PM
  #23  
Burzel55
Rennlist Member
 
Burzel55's Avatar
 
Join Date: Dec 2017
Location: North East
Posts: 65
Received 5 Likes on 5 Posts
Default

Great thread


Last edited by Burzel55; 02-20-2022 at 09:49 PM.
The following users liked this post:
LOMartin (02-20-2022)
Old 02-20-2022, 09:48 PM
  #24  
Burzel55
Rennlist Member
 
Burzel55's Avatar
 
Join Date: Dec 2017
Location: North East
Posts: 65
Received 5 Likes on 5 Posts
Default

Originally Posted by LOMartin
Update:

The suspension will settle a little, I just lowered the lift.

​​​​​​I went with the setup that @bweSteve posted above, and it looks great. Now I’m thinking if I should push the front wheels out a bit?






What make is the lift in this photo? Looks great. The car looks Great too!!!
Old 02-20-2022, 10:48 PM
  #25  
LOMartin
Advanced
Thread Starter
 
LOMartin's Avatar
 
Join Date: Aug 2020
Location: South/East USA
Posts: 96
Received 43 Likes on 31 Posts
Default

Originally Posted by Burzel55
What make is the lift in this photo? Looks great. The car looks Great too!!!
Twin-Busch Low Rise.
Great customer service and product. This specific model is niche, I have very low ceiling in my current garage of 84”. This low rise lift is portable and fit my space.

My plan is to keep this lift for detailing my car, but I do need a two post in the future for more involved work on sports cars and the trucks.

Twin-Busch Link




note: Yes, I did order a new grill to fix the smile.

Old 02-21-2022, 01:15 AM
  #26  
bweSteve
Rennlist Member
 
bweSteve's Avatar
 
Join Date: Mar 2015
Location: Baltimore Maryland
Posts: 4,085
Received 1,049 Likes on 666 Posts
Default

You should not really need a new grille to fix the frown (well in your case it does look like a smile).

It is usually just the task of using a pair of platypus vice grips & bend the body crimp back straight. There are lots of threads on this, so I hope you've checked them out first (might be an easier search in the regular 964 subforum)

Re: Lifts for low ceiling garages,.... I thought about a scissor too (but the RLP77 was just soooo expensive),... so I went with the MaxJax 2-post lift. Absolutely love it. I ran the hydraulic lines up to the ceiling and over to my wall for a permanent mount of the pump/motor/reservoir,... so I have 100% complete unencumbered access on the floor underneath the car. I have a 9 ft ceiling height.

Last edited by bweSteve; 03-13-2022 at 08:24 PM. Reason: ...
Old 02-21-2022, 02:17 PM
  #27  
heliolps2
Rennlist Member
 
heliolps2's Avatar
 
Join Date: Mar 2011
Location: Vienna, VA
Posts: 1,069
Received 152 Likes on 105 Posts
Default

Thank you for the posts guys, I also have the RH"s 3.6 10.5, and 8's right now I have Sumitomo HTR-Z 295/30/18 and 225/40/18 and they look great, the side profile design looks amazing, just the right amount of stretch and bulge but not happy. with the performance. I wanna upgrade to the PS4S's.even though I'm not happy about the look of the tire side profile. the specs on the 225's are the same specs on both manufacturers, so no issue there.

My issue is the rear specs. My issue is the thread width 11" vs 10.4", I don't want the tires to look bulky.

Michelin PS4S 295/30/18 specs Rim width 10.5", sect width 11.8", tread width 11" and overall diam 25"
vs what I have now,
Sumitomo HTR-Z 295/30/18 specs Rim width10.5", sect width 12", tread width 10.4" and overall diam 25"

I'm looking for your thoughts and pic's please Here are some pics from my files, I hope this helps.






The following users liked this post:
LOMartin (02-25-2022)
Old 02-25-2022, 09:53 AM
  #28  
Metal Guru
Rennlist Member
 
Metal Guru's Avatar
 
Join Date: Apr 2007
Location: Beverly Hills, Mi.
Posts: 4,521
Received 429 Likes on 309 Posts
Default

Got a fresh set of Conti Extreme Contacts earlier this week;235's and 295's. I've run Sumitomos for years and figured I'd try something else (my son's Conti employee discount helped with that decision ). Will be mounting on my new Speedlines next week.
I'm now really looking forward to spring....


Last edited by Metal Guru; 02-25-2022 at 09:56 AM.
The following 4 users liked this post by Metal Guru:
bweSteve (02-25-2022), heliolps2 (02-26-2022), LOMartin (02-25-2022), urquattro20Vt (02-25-2022)
Old 02-28-2022, 03:23 AM
  #29  
Mdiesel64
Rennlist Member
 
Mdiesel64's Avatar
 
Join Date: Nov 2019
Posts: 98
Received 39 Likes on 19 Posts
Default

Originally Posted by revolution993
Running RH 8.5 and 10’s but 40ET rear . I went with recommended size from porsche 225/265
How's the clearance on these from fender to tire? I have been looking for someone with an aggressive enough offset and this might be the lowest I've seen thus far.
Are you running stock control arms etc, or did you convert to NB?

Originally Posted by LOMartin

​​​​​​I went with the setup that @bweSteve posted above, and it looks great. Now I’m thinking if I should push the front wheels out a bit?






Curious if you mean the setup for the tires or the size of the wheels. Trying to follow along. The rears look to have a nice sized lip! Interested to know final specs on the wheels.
Old 02-28-2022, 11:00 AM
  #30  
bweSteve
Rennlist Member
 
bweSteve's Avatar
 
Join Date: Mar 2015
Location: Baltimore Maryland
Posts: 4,085
Received 1,049 Likes on 666 Posts
Default

Originally Posted by heliolps2
Thank you for the posts guys, I also have the RH"s 3.6 10.5, and 8's right now I have Sumitomo HTR-Z 295/30/18 and 225/40/18 and they look great, the side profile design looks amazing, just the right amount of stretch and bulge but not happy. with the performance. I wanna upgrade to the PS4S's.even though I'm not happy about the look of the tire side profile. the specs on the 225's are the same specs on both manufacturers, so no issue there.

My issue is the rear specs. My issue is the thread width 11" vs 10.4", I don't want the tires to look bulky.

Michelin PS4S 295/30/18 specs Rim width 10.5", sect width 11.8", tread width 11" and overall diam 25"
vs what I have now,
Sumitomo HTR-Z 295/30/18 specs Rim width10.5", sect width 12", tread width 10.4" and overall diam 25"

I'm looking for your thoughts and pic's please Here are some pics from my files, I hope this helps.
Helio,

As I mentioned in my posts above, I did notice less stretch with the new PS4S (but keep in mind, I am running the 285).

If you think your Sumitomo's are "perfect" for you now,... then yes, the difference in side buldge between the two tires, in your case, will probably not be exactly to your liking.

The section width differences (.2" between the two), and especially the tread width difference (.6" between the two),... will probably make enough of difference to you.

Is your 10.5" rear rim a ET59? ... If so, and you want that particular PS4S to stretch more,... than maybe an 11" rim would do that for you. But then you'll need a VERY specific offset so the inside of your rear tire does not rub the trailing arm.

With my setup (as I described above), the inside of my 285/30/18 comes very close to my trailing arm (like within 1/4"),... which is plenty close enough for me, given the little amount of "roll" the tires will experience when under heavy cornering loads. Plus, as I said, these new PS4S tires are sooooo much bigger build than any other 285 I have ever seen on the market. It is why I am in the 285 (which looks dang close to the size of my 305/30/19's on my blue car).

Hope that helps.

Last edited by bweSteve; 02-28-2022 at 11:01 AM.


Quick Reply: RH 3.6 Tire Sizing



All times are GMT -3. The time now is 03:21 AM.