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Tires

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12-15-2006, 04:43 PM
Gary Carter
Tires
8R19.5 tires are 619 revs per mile. Thinking of going to 9R22.5 with 543 revs per mile. This gives me about 74 mph at 2500 rpm. Also 65mph at 2200 rpm. Much more liveable.

I understand that some Breakaways had 22.5" rubber, but mostly has anyone ever done this change.


'92 Barth Breakaway - 30'
5.9 Cummins (6B) 300+ HP
2000 Allison
Front entrance
12-15-2006, 06:02 PM
MWrench
HI Gary

You might find that 9R22.5 tires will not fit into the wheel well, also I don't know if there is a wheel that is available in 22.5 size with a 6 bolt Budd pattern. On my Breakaway, in a hard turn, the front 9R19.5 would rub on the backside of the wheel well, I have replaced the fronts with 225R19.5 and they are smaller in diameter and just barely touch now.

I am looking for 19.5 inch wheel that have a rim width of 7 inches so I can go with 245R19.5 which are the same overall diameter as 8R19.5 but would have a lot more meat on the road and I could get "G" rated as well.


Ed
94 30' Breakaway #3864
30-BS-6B side entry
New Cummins 5.9L, 375+ HP
Allison 6 speed
Spartan chassis
K9DVC
Tankless water heater
12-15-2006, 06:37 PM
bill h
Sounds like you will end up with a permanent overdrive. There is a possibility that you will hurt your first gear acceleration.

Perhaps the owners of six-speed Breakaways can comment on the cruise speed and rpm.

And climbing ability.


.

84 30T PeeThirty-Something, 502 powered
12-16-2006, 12:27 PM
Gary Carter
There appears to be a 6 bolt wheel that will fit.

Also found out there is a 3.31 ring and pinon set available.

I realize it will be somewhat slower off the line, but it sets you back in your seat now. But, since we just got this a couple of months ago, I need to hook up the tracker on the back and head east over the mountain here in Yuma to check out the hill climbing ability before making a final decision.


'92 Barth Breakaway - 30'
5.9 Cummins (6B) 300+ HP
2000 Allison
Front entrance
12-21-2006, 12:41 AM
MWrench
Gary, I just measured my Breakaway and 22.5 wheels and tires will not fit into the wheel opening. 22.5 tires are 37.6 inches in diameter vs. 33.0 for the 8R19.5. That is an increase of 4.6 inches, looking at the radius increase, of 2.3 inches the tire will scrub the rear of the tire area at the back edge of the floor board and will not turn without hitting the edge of the fender well.

HTH


Ed
94 30' Breakaway #3864
30-BS-6B side entry
New Cummins 5.9L, 375+ HP
Allison 6 speed
Spartan chassis
K9DVC
Tankless water heater