Ok all you 8" rear swap guys. Have you had pinion angle problems at all? I noticed after I bolted in this 8" rear that the pinion angle is different. It points up a few degrees at rest which I am sure is the opposite of where it should be. Do they make special shims for Ford axle pads so I can rotate the rear back down? I looked at Summit Racing but didn't see anything that would fit over that elongated hole in the spring pads.
Help....I'm almost done...
Joe
Joe,
I can't help much on the angle shims , but if the rear spring are the stock arch, couldn't you use lowering blocks? I have about 2'' blocks on my car with 21.5" diameter tires, cut the rubber snubber and axle bumpers to compensate for travel and no issues with the axle or yoke travel with Different leaf springs.
Just my 2 cents
Pintosopher
Joe,
West Coast Classic Cougars in Portland Oregon has Wedges in different degrees. Sold in pairs about 30 bucks. It's the Springs that are causing the angle issues.
Let us know what you find out, they're on the web..
Pintosopher
I'll check them out. Is that a typical problem with the swap? this is the first I've heard of this unless I just happen to have an oddball 8" rear. It was supposed to have come from a Mustang II
Joe
Joe ,
I'm not sure if the Spring pad is parallel to the Pinion shaft. Mine actually points down a bit at the driveshaft. Must be the springs that I have (Chrysler).
Check out Mustang II.Org site too.
Pintosopher
I think I solved the pinion angle problem. When I was taking the old rear out I took pictures and noticed one of the driveshaft connected to the old rear. The pinion of the old rear was also pointing up in relation to the driveshaft angle. Ford didn't build it that way. That meant only one thing. The T5 was way too low at the tailshaft. I measured the stock and T5 mounting surfaces in relation to the centerline of the output shaft, and sure enough, there is a major difference. The T5 pad is approx 3" below the center of the tailshaft and the stock 4 speed pad is about 4" below the center of the tailshaft. Basically, using the same trans mount for the T5 will lower the tailshaft by as much as an inch which will throw off the stock angle of the driveshaft. This may explain the high speed vibration I have had since I installed the T5. If you run U-joints at too much of an angle they will cause a vibration and with the angles I have going on, the more load on the rear, the springs wind up more making the angles worse.
I'm going to cut the trans tunnel more so I can raise the T5 up. Hopefully that will solve several problems.
Joe
Ideally, the angles of the pinion and the crankshaft/trans. mainshaft should be the same. Before you start cutting the tunnel, get an magnetic angle finder and determine how far off the angle is. If the t5 has more downward angle than stock, then the pinion must be raised. Using rearend shims "may" cure your problem.
For a street car, the rearend angle can be as much as 3 Degrees down. Also the crank and the pinion will have opposite angles - meaning if the trans is down 5 degrees, the pinion must be up 5 degrees [not less than 2 degrees up].
You are correct. I've been doing a lot of research on this and ultimately want to come out with the correct angles. I found one mistake I made when I installed the 8. I used Mustang II spring plates which had a thin metal spacer, which I didn't realize at the time was a tapered shim!! Not noticing the taper, I inadvertantly installed them in reverse, actually pointing the pinion up more!! DUH!! I hate doing stuff twice. I flipped the mounts today and the rear looks better. Once I get the center section back I can check angles. I only opened the hole in the tunnel to give enough clearance for the shifter to come up a little when I raise the trans. I'm 99% sure that the tranny is too low and can get another 3/4" height out of it without hitting the floor. I should know in a couple of days....just waiting for parts.
Go to http://www.cadvision.com/blanchas/Ranger/pinionangle.html (http://www.cadvision.com/blanchas/Ranger/pinionangle.html) to see why and how to set the pinion angle. Also a very good 2.3 mod site.
Thanks for the link. Another cheap way to measure the angles is to use a regular angle finder that you would use for wood construction and a level. Then you transfer the angles to a piece of paper and simply compare them with a protractor. I plan on doing that after I bolt in the 3rd member.
Joe
Finally got it done and it runs nice and smooth. As it turns out, I had to lower my T-5 at the rear to get at least close to the optimum angle for the rear. To make it perfect I would need to subtract about -2 degrees to the pinion angle at the rear with shims, but there are no vibrations at all anymore, so I'll leave it for now. I also discovered that my trans was angled slightly to the right, so my driveshaft was compensating for two different angles at the same time. I did the plumb bob trick where you tie a string around the crank pulley at the front, at the front yoke of the driveshaft, and the rear yoke of the driveshaft, tie a nut on the end of each string making sure the strings are hanging from the center of the three points. Then you simply look down the row of strings from the front or the rear and see if they all line up. If they do, your driveline is nice and straight. If the back of the trans is a little sideways like mine was, the middle string won't line up with the others. I modified my tranny mount a little and brought it back in line.
Thanks for all your comments guys! Now to do the ring job!!