My 245/45/17's aren't cutting it, I don't have enough rear traction. Between the 17x8's and the Bullitt brakes on the front, it is crazy easy to lock up the tires under moderate braking. I am looking at moving up to 17x9's all the way around, and I would like to be able to rotate the tires. This doable? My google-foo is failing me.
What Do You Guys Think? 275/40/17's On The Front Of A 91lx?
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mikestang63
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doable? maybe- depends on the backspacing and fender rolled. I think you will be tramlining the crap out the road though.
Just the fronts. Running Ranger drums and Moser 5 lugs in the rear. Car tracks straight, but with the cooler weather and old tires (put them on the car in 2010). Just ain't getting the job done.
Six year old Cooper Zeons. They have tons of tread cause they only have about 2K miles on them, but the rubber is old.
Maybe adjust the proportioning valve a hair for a little less front and a little more rear too?
Running the factory MC, booster, and prop valve. Car didn't used to do this quite so much, I think it is due to the tires aging. I am kind of tired of the Bullitts and was looking at this as an opportunity to change it up a bit.
Just look at this:
View: https://www.youtube.com/watch?v=U2PexROPTkc
Terrible...
I wouldn't even attempt it without a cobra steering rack or some sort of additional stabiliser. The first rut in the road is going to snatch the wheel right out of your hand
Personally I think it's the tires more than anything. I've got cobra brakes all around and can get on it pretty hard and my issue is locking the rears up. Front tires are Toyo Proxes.
I assume you have rear drums? I bet you have too much front bias as well and could use a touch more rear pressure. You can gut the factory prop valve and install and adjustable to be able to add a little more rear bias
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I assume you have rear drums? I bet you have too much front bias as well and could use a touch more rear pressure. You can gut the factory prop valve and install and adjustable to be able to add a little more rear bias
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- Mar 2, 2015
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I thing an adjustable prop valve would help you out a lot, too.
The rear should hit just a split second before the front. That's how you keep it from nose diving and throwing all the weight up front. Too much to the rear and the back will grab and slide...causing bad things to happen.
The rear should hit just a split second before the front. That's how you keep it from nose diving and throwing all the weight up front. Too much to the rear and the back will grab and slide...causing bad things to happen.
Could be the tires age showing the weakpoint in the system then. I have been driving it like this for several years (when it wasn't broken) and I don't recall it never acting like this before. I think I actually have an adjustable prop valve on the shelf. Where is a good point to install it?
- Dec 19, 2010
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There is a couping on the line on the passenger side firewall that gets removed and the prop valve goes. I'll see if I can find a pic.
- Dec 19, 2010
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Yup. That's the spot. You'll need to gut the factory one first with this stupidly overpriced plug
https://lmr.com/item/M2450A/Mustang-Brake-Proportioning-Valve-Plug
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https://lmr.com/item/M2450A/Mustang-Brake-Proportioning-Valve-Plug
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- Dec 19, 2010
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I prefer the factory prop valve eliminator kit. The problem with gutting that prop valve is if you pop a hose, be it front or rear.. you lose pressure everywhere. Front and back. May as well do it right. I did.
- Dec 19, 2010
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Shuttle valve still remains intact in the rear of the combo valve in the stock setup, so it should reduce flow if a line bursts.
Either way works fine really. The delete looks cleaner, but the nut is probably an easier install if all your brake nuts are frozen and rounding off.
Shuttle valve part is the spring on the left. Part you gut is on the right
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