Author Topic: I'm confused tire ratings - 165/50R15 73V - how fast does SCTA permit on these?  (Read 10352 times)

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Offline fredvance

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When were the tires manufactored?
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Offline NathanStewart

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Honestly, this is a pretty simple question with a pretty simple answer.  The tire in question is a 165/50R15, 73V.  The fact that there is a R and V in the tire description doesn't make it a VR tire and doesn't make it a 200 mph tire.  It's pretty clear that 73V is the load and speed rating.  Load rating is 73, speed rating is V.  The R in this case and pretty much all other cases where it comes between the aspect ratio and the wheel size denotes that it's a radial tire and that's it.  

This is definitely an "inspector-level" type question IMO.  No real need to ring up the big guns for such a minor question.  If there was something to contest and a decision was needed then yeah, hit them up but I don't really think that's the case here.  One problem with only contacting someone within the association and not posting here is that someone else with the same or similar question doesn't get to see the answer or the discussion therein.  

BTW I've already been down the V rated tire road with Excelsior Comp-V tires.  They're sold as a vintage style "competition" tire but only have a V speed rating.  Car that showed up with them was limited to 150mph.  

Sometimes I speak from experience.  
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Offline SteveM

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Seems nobody mentioned the vehicle has to be legal and running all the gear, minimum requirements for the speed in the class for which they are running in..looks like at ElMo and Bonneville the records are less than 106 mph..in the HDT class..

The Bonneville record is 135.003 mph in H/DT 

The ECTA record (Ohio Mile) record is 135.624 mph in H/DT

I currently hold both of those records, and certainly hope to push both of them higher in 2016.

The El Mirage record is still 104.8xx mph, held by Pat Manghelli.

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Offline SteveM

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When were the tires manufactored?

2013.
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Offline NathanStewart

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Also, FWIW, when it comes times for rule change submissions next year, I'll put one in to update the street tire specs.  The old and outdated specs get over looked because there aren't many competitors running street tires.  There's been a pretty big push to require that competitors follow manufacturer specs for safety equipment (seat belts and head and neck stuff comes to mind) because the manufacturers obviously know how their equipment is to be installed/used better than the SCTA does.  I have a feeling that allowed speeds for certain tire specs might drop to the manufacturers published speed rating should the current SCTA spec be higher.  Doing otherwise opens up the association to liability risk.
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Offline salt27

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Nathan,
  Thanks for taking action on this. 

  Don

Offline SteveM

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I don't know what the official ruling with be with respect to allowable speeds for current V-rated (As opposed to pre-1991 VR rated) tires, but this table from tiresafety.com seems to indicate that the ratings are equivalent....

http://www.tiresafety.com/sizes/passenger/speed.asp

I have submitted an inquiry to SCTA requesting clarification on this issue.

Thanks, everyone.

Steve.
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Offline Sumner

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I don't know what the official ruling with be with respect to allowable speeds for current V-rated (As opposed to pre-1991 VR rated) tires, but this table from tiresafety.com seems to indicate that the ratings are equivalent....

http://www.tiresafety.com/sizes/passenger/speed.asp

I have submitted an inquiry to SCTA requesting clarification on this issue.

Thanks, everyone.

Steve.

Yep, the difference between a VR and a V tire is in name only, just like now we call a Datsun a Nissan  :-).  They just got rid of the R part after 1991.  Same specs., has to pass the same lab certification and so on...

Sumner