80 & 85 mph speed limits

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dibbons

dibbons

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Was just reading in parts of Idaho, Montana, Nevada, South Dakota, Texas, Utah, & Wyoming one can find posted speed limits of 80 mph and even 85 mph on toll road 130 in Texas. Can forum members verify this? Sounds too good to be true.
 
Highest I know of is the toll freeway between Denver airport and Colorado Springs is 75, I believe. Been a few years since I was on it.
 
Just returned from a 4,600 road trip thru Mexico (the country not the state) and California in my '72 Bbody. I swear many of the 18 wheelers on hwy 5 between Los Angeles and Sacramento were doing a good 70 mph and not the posted truck speed limit of 55 mph. Nary a patrol car in sight either.
 
I 15 north out of Vegas is 75, then is 80 out of ST George to Salt Lake Utah.
 
I just drove from SoCal to Indiana via the 15 to Las Vegas, then the 70 through Denver. Most of the way on the 70 in Utah and Colorado was posted at 80 MPH.
When I picked up the 80 in Nebraska, the speed limit was 70-75 outside of city limits.
 
The interstate limits in Louisiana are 75 in rural areas. I believe the State Police backed raising them from 70. Supposedly the accident rate has been less. I don't know if this includes the bad stretch of I49 south of Alexandria where hydroplaning is unbelievable and many single car accidents happen because people can't stay on the hiway during rain storms.
 
Yep, Toll 130 is 85mph...but you pay for it every few miles. San Antonio to Austin is about $30-35 IIRC.
IH-35 is 70mph and 75mph except in Austin. This is why I won't give up my 3.23 gears for better ET's.
 
I15 in Utah has been 80mph since at least 2012, if I remember right. Why the interest? You have a death wish or something? Your typical A-body is not going to be a very happy camper at 90mph...much less enjoyable at that speed.
 
The reason for my interest in speed limits is: I'm rebuilding the front end of my '72 Satellite Sebring Plus 318. When I install the de-stroked 340 I am building (305 CID) I plan to use a '68 factory 340 camshaft and keep the 2.71 rear end. The smaller motor will probably be happier cruising at 3000 rpm (84 mph) than the current 318 which is happy at 2500 rpm (70 mph).
P.S. I suppose I could also experiment with running in second gear (Torqueflite) at 3500 rpm (about 70 mph). That would be the equivalent of a 3.91 rear end ratio in "drive" by way of the math: 1.45 x 2.71 = 3.93. Dont know what that would do to fuel mileage though.
 
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That's why we have 2.45 gears available. If you do any Interstate driving 75 or above, 3.23's are not going to cut it. 2.71 or 2.76 are a must! Disregard this post if you have an overdrive.
 
Wait, a 305 with a 268* in a 72 Sebring, to cruise at 80 plus mph?I'm hooked;what's the rest of the story?

BTW, You gotta kick out the caster to the max for that, and then fix the bumpsteer, plus the biggest T-bars springs,and anti-sway bars. Not to mention appropriate tires and shocks. But Ima guessing that you're on top of that, already.
And don't leave home without earplugs.
 
The cam is the 276/284 version not the 268/276, already had it custom ground. I have the 1.03 torsion bars ready to install. The caster is a good idea. The "purple horny" glass packs are a little loud now, although they do quiet down some at cruising speed. I will probably add some resonators to the current dual side exhaust. My For Bbodies only build thread is: Introducing "Project Odyssey" a 1972 "Super Satellite". Super Satellite meaning a 1970 Superbird rear spoiler and the never produced 1971 Plymouth Road Runner Superbird nosecone as found on the MPC 1/25 model kit #6282.

I currently have old school NOS TRW 11
.5 dome pistons (after de-stroking they only work out to 10.5), custom length rods (6.298" vs 6.123" stock) , open chamber "O" cylinder heads with 2.02 intake), 1972 factory thermoquad and factory '72 intake to match. Just waiting for the custom Bryant Racing billet crankshaft to be machined to the correct 2.96" stroke. Then its off to the "races".
 
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In the N end of Idaho, if you were anymore than 5 over the limit you might want to keep an eye out. Nowadays, "the I" routinely sees average cruising speeds of 75 with a 70 limit

I either keep up or get out of the way
 
Interstates in ND are at 75. In SD the post is for 80, but HP doesn't allow much over. Our 14 Charger loves that speed.
 
Sorry, I was actually referring to the freeway rat race.

But the car is supposed to mimic a "could have been" 1972 winged Mopar NASCAR small block after the 1971 rule change that limited the Superbird and Dodge Daytona to 5.0 liters.

Owner Mario Rossi ran a Keith Black 305 in his '69 Dodge Daytona against big block hemis and big block Ford/Chevys in the first NASCAR race of 1971, the Daytona 500.
In other words, my project car is supposed to be the factory offered street version sold at dealerships, if Chrysler had followed through with their wind tunnel studies on the "fuselage" style '71 and '72 Bbodies and then actually produced vehicles available to the public to conform with new restrictive NASCAR displacement ruling. However, Chrysler decided to bail out on that program instead.
 
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I recall driving at 100 MPH and higher on ice- covered roads in Wyoming in the late 1980s. I worked for RCA and they sent me there on a consulting trip for a secret government project. They hired a bunch of young PhDs and they lived in a farm house out in the boondocks of Wyoming. They had an antenna array that had a 150 mile diameter and their masts were shattering. They drove (while I followed in my rental car) at over 100 MPH on ice covered roads to show me their problem masts and I thought I was going to buy the farm more than once. Scary trip! They were not concerned with getting a speeding ticket.
 
Remember when Montana's posted speed limit was "Reasonable and Prudent"?

I drove through in 1993 doing 85 mph the entire way.
 
Until March 2007 it was legal to drink and drive in Wyoming, you just couldn't drive with an alcohol level over the legal prescribed limit. In 2007 they introduced the first open container law.
 
68gtxman said:
I recall driving at 100 MPH and higher on ice- covered roads in Wyoming in the late 1980s. I worked for RCA and they sent me there on a consulting trip for a secret government project. They hired a bunch of young PhDs and they lived in a farm house out in the boondocks of Wyoming. They had an antenna array that had a 150 mile diameter and their masts were shattering. They drove (while I followed in my rental car) at over 100 MPH on ice covered roads to show me their problem masts and I thought I was going to buy the farm more than once. Scary trip! They were not concerned with getting a speeding ticket.
Click to expand...

A couple years back a friend and I were running from Jackson hole to SLC. Cruising speed was around 100 but the little Ford Focus could only reach 120. As soon as we got onto the interstate and around other cars we slowed it down the the speed limit. Ten minutes later we are sitting on the shoulder getting FIVE tickets at one time and not one was for speeding.
 
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