manual says "inflate to 32psi"... but when?
#28
Senior Member
![](https://www.rx7club.com/images/misc/10_year_icon.png)
Join Date: Jul 2001
Location: Princeton, IL
Posts: 513
Likes: 0
Received 0 Likes
on
0 Posts
And be very careful when you get tyres mounted. I watched in disbelief as they inflated my tyres to 50psi "because it's the max". I even had to sign a waiver because I wanted my tyres at 30psi.
#29
2/4 wheel cornering fiend
![](https://www.rx7club.com/images/misc/10_year_icon.png)
Originally Posted by DrPJM1
And be very careful when you get tyres mounted. I watched in disbelief as they inflated my tyres to 50psi "because it's the max". I even had to sign a waiver because I wanted my tyres at 30psi.
#30
Originally Posted by dgeesaman
Yes absolutely. Driver door pillar.
Dave
Dave
![Stick Out Tongue](https://www.rx7club.com/images/smilies/tongue.gif)
Originally Posted by Kento
They're doing that to cover their ***; that way, if you have a blowout for whatever reason on the highway and you come blaming them, they have an out. No drama, just deflate them to your own specs after you drive off; it's really your responsibility anyway to ensure that your tires' inflation pressures are correct.
![scratch](https://www.rx7club.com/images/smilies/scratchhead.gif)
#31
2/4 wheel cornering fiend
![](https://www.rx7club.com/images/misc/10_year_icon.png)
Originally Posted by FDNewbie
Kento, am I getting the impression that you are more likely to have a blowout by underinflating the tires? Cuz I thought the more pressure, the more likely it is to burst, esp. when ppl overinflate them when it's cold out, and go for a hard drive, temps get up, pressure rises, and kaboom... So I don't see why a shop would have a prob w/ you UNDERinflating them ![scratch](https://www.rx7club.com/images/smilies/scratchhead.gif)
![scratch](https://www.rx7club.com/images/smilies/scratchhead.gif)
Last edited by Kento; 12-17-04 at 01:35 AM.
#32
Rotary Freak
![](https://www.rx7club.com/images/misc/05_year_icon.png)
Join Date: Sep 2004
Location: Bay Area, CA
Posts: 2,444
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by FDNewbie
given that my 285/30/18s ran me $189 a pop, vs. Pirelli PZeros that run $289 a pop, and last a whopping what, 7K miles?
#33
Racecar - Formula 2000
![](/images/misc/20_year_icon.png)
You often see tire failures where the entire tread area (belts and tread) separates as a unit from the sidewalls at the shoulder. This is caused by SEVERE underinflation (less than 10 psi) causing so much flex and heat buildup in the shoulder that the polyester body plies actually melt and the tire comes apart.
This can happen quite easily, since, with stiff carcass constructions, it is extremely difficult to feel when a tire is underinflated. We see this sort of thing happen very often in professional racing series where the tire constructions are extremely stiff.
Overinflation, unless the tire is overinflated by a huge amount, will not increase the likelyhood of a failure unless you hit something that punctures the tire or breaks cords.
This can happen quite easily, since, with stiff carcass constructions, it is extremely difficult to feel when a tire is underinflated. We see this sort of thing happen very often in professional racing series where the tire constructions are extremely stiff.
Overinflation, unless the tire is overinflated by a huge amount, will not increase the likelyhood of a failure unless you hit something that punctures the tire or breaks cords.
#34
Originally Posted by FDNewbie
Kento, am I getting the impression that you are more likely to have a blowout by underinflating the tires? Cuz I thought the more pressure, the more likely it is to burst, esp. when ppl overinflate them when it's cold out, and go for a hard drive, temps get up, pressure rises, and kaboom... So I don't see why a shop would have a prob w/ you UNDERinflating them ![scratch](https://www.rx7club.com/images/smilies/scratchhead.gif)
![scratch](https://www.rx7club.com/images/smilies/scratchhead.gif)
![Smilie](https://www.rx7club.com/images/smilies/smile.gif)
#35
2/4 wheel cornering fiend
![](https://www.rx7club.com/images/misc/10_year_icon.png)
Originally Posted by DaveW
You often see tire failures where the entire tread area (belts and tread) separates as a unit from the sidewalls at the shoulder. This is caused by SEVERE underinflation (less than 10 psi) causing so much flex and heat buildup in the shoulder that the polyester body plies actually melt and the tire comes apart.
I just don't want people to think by your post that they'll run into problems only if they run their tires at less than 10 psi.
#36
Racecar - Formula 2000
![](/images/misc/20_year_icon.png)
Delete - double post.
Last edited by DaveW; 12-17-04 at 12:15 PM.
#37
Racecar - Formula 2000
![](/images/misc/20_year_icon.png)
Kento, Thanks. I did not mean to imply that, either.
I know all about "BLB" (belt-leaving-belt) tread seps. The Ford Explorer/Firestone fiasco...
I know all about "BLB" (belt-leaving-belt) tread seps. The Ford Explorer/Firestone fiasco...
#38
Originally Posted by BlueRex
Do what everyone else does and keep a good set of rims and tires for the track, auto x, etc. and a set for the street. That way you can have the good tires readilly available when you need them and it won't cost you a fortune driving on them around town.
#39
i think it was car and driver had an article where they underinflated a tire and drove it over a plexiglass screen with a camers under it and compared the tire's footprint with a properly inflated tire. pretty scary as you could see the middle of the tire was loosing contact with the road. dont remember the exact psi below recomended but it was not alot.
#40
2/4 wheel cornering fiend
![](https://www.rx7club.com/images/misc/10_year_icon.png)
Originally Posted by FDNewbie
I thought about that, but I was under the impression that you should have an alignment check every time you switch tires/rims. Or is that not the case?
Last edited by Kento; 12-18-04 at 07:25 PM.
#42
2/4 wheel cornering fiend
![](https://www.rx7club.com/images/misc/10_year_icon.png)
Originally Posted by mad_7tist
i think it was car and driver had an article where they underinflated a tire and drove it over a plexiglass screen with a camers under it and compared the tire's footprint with a properly inflated tire. pretty scary as you could see the middle of the tire was loosing contact with the road. dont remember the exact psi below recomended but it was not alot.
#44
Rotary Freak
![](https://www.rx7club.com/images/misc/05_year_icon.png)
Join Date: Sep 2004
Location: Bay Area, CA
Posts: 2,444
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by FDNewbie
I thought about that, but I was under the impression that you should have an alignment check every time you switch tires/rims. Or is that not the case?
I guess whether or not it's worth it to you depends on a few factors:
1. How often do you track (or other automotive competition)?
2. How many miles do you drive around town?
3. What type of tire do you want for each type of driving?
I'm not sure what types of regulations the road courses have in your area, but I know when the car club at my college goes to Streets of Willow, they have a full inspection done. They often replace brake components, get alignments and what not (at a discounted price due both to it being a large group and the club president having a previous relationship with the owner).
Maybe you and some fellow forum members can go get alignments, and other maintenance together and try to negotiate a group price. There are deals to be had if you're patient and know the right people.
![Wink](https://www.rx7club.com/images/smilies/wink.gif)
#45
Originally Posted by BlueRex
Maybe you and some fellow forum members can go get alignments, and other maintenance together and try to negotiate a group price. There are deals to be had if you're patient and know the right people. ![Wink](https://www.rx7club.com/images/smilies/wink.gif)
![Wink](https://www.rx7club.com/images/smilies/wink.gif)
![Wink](https://www.rx7club.com/images/smilies/wink.gif)
Thread
Thread Starter
Forum
Replies
Last Post
joel(PA)
Group Buy & Product Dev. FD RX-7
8
10-04-15 06:07 PM
joel(PA)
Race Car Tech
0
10-01-15 10:25 AM