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Tire pressure

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vping

vping

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I read in the moss catalog that the tire pressure in the rear should be 3-5 #'s less than the front.

Is this true for better handling?
 
I assume you are looking at page 3 in the cat. It does say 4 lbs higher in the rear but also says " original ' pressure so that would be for cross ply tires. That was fairly common ( from memory ) for rear wheel drive but for most of us who use radials it would not apply. People run radials at higher pressure - 28/30 lbs seems to be the norm. Bit harder ride but easier stearing at low speed for a car without steering assistance.
 
I always go with what the decal in the glovebox says for street use...or the max on the side of the tires if different.
 
I've seen new cars (erm... trucks rather) recommend differing tire pressures between front and rear. The difference in pressure was about 5psi with the front being lower than the rear. If you go with the recommended pressures it might help reduce the amount of understeer you might experience at the limits. Or you could go with the max PSI on the rear and set the fronts the at a lower pressure so that the difference between pressures is identical to the recommended. I.E. if the recommended it 27F 32R, then you'd set the rear to max (44PSI for my tires) and the front 5PSI lower which would be 39PSI in my case.
 
Don't know if I have a sticker in the glove box. I ain't gots da key!!

I get a little bit of a hop left to right while accelerating through turns, over a bump. I also hear a bit extra revs when this happen so I assume my tire might be coming off the ground a bit. Could this be shackles? Bushings?

Shocks "seem" OK but I need to check the fluid level & operation on them.
 
Check your spring hanger bolts.
 
on my car the ignition key opens the glove box. - but only goes in about half-way.
 
Kenny - it shouldn't
 
The number molded into the sidewall of the tire is not the pressure you should run -- it's the pressure you SHOULDN'T exceed. The proper pressure is going to be as much a function of the car that it's on as it is of the tire itself. If your car is bouncing around, you may be running too much pressure.

If you feel like playing, here's how to derive a good set of pressures for your car:
https://mgaguru.com/mgtech/tires/tt102.htm
Start reading with the above page, and follow the links.

FWIW, I run about 25 psi front, 28 psi rear. I haven't performed Barney's experiment, but the car seems to feel pretty good with those pressures.

HTH!
 
Maybe I got an odd, lucky combination of tumblers that works that way, but only the ignition key will lock or unlock the glove box on my car... The little key only locks or unlocks the doors, and the boot.
 
What am looking for on the Spring hanger bolts? Looseness?

Interesting read on tires pressures. I don't know if I'll go that crazy but I will be thinking about it the next time I am on the road.
 
Tire pressure is set based on many factors including tire construction, tire materials, vehicle weight, vehicle balance, driving habits and many others. The factory specification on early MGBs was for tall, skinny bias-ply tires. Running a modern radial at such low pressures will cause uneven wear, poor fuel economy and sloppy handling. Likewise, running too high a pressure will cause a harsh ride, unpredictable handling, overheated tires and rear end skipping on rough surfaces.

Typically MGBs on radial tires will run between 27-30 PSI in the front and 28-32 in the rear. I have found that on 175/70R14 I like 28/32 and on 195/60R15 I prefer 30/30. So you need to experiment with YOUR tires on YOUR car driving the way YOU drive. Just start at around 28/30 and adjust daily from there. You will eventually find a pressure you like where it balances ride quality with good handling.
 
[ QUOTE ]
What am looking for on the Spring hanger bolts? Looseness?

[/ QUOTE ]

Yep, looseness, worn out bushings, bolt hole wallowed out.
 
Allen Hendrix of Hendrix Wire Wheel in Greensboro NC told me to carry 28 lbs in the front and rear tires. My car rides and handles like a dream. I use Vredestein 165/14 tires. /ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/thumbsup.gif PJ
 
175/70R14's here and I've a 28/32 preference as well. A 4-pound differential seems to be the best.

Semperit was my tire of choice back in the day, now it's whatever fits.
 
I run about 30 lbs equal all around in mine... I could never tell the difference in offset pressure front and rear, but then I don't drive it like a racecar either.
 
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