Can any one tell me if the bump stop is the center of the rearend. I marked the center on the frame when I removed it but my son sanded off the marks. But the bump stops don't look right to me.(but what do I know). I think the marks were an inch or so toward the front. But not sure. The Jag mounts to a crossmember that is welded to the frame. The pumkin does not move. HELP

 

I just went out to the garage and checked mine. The bumpstops are approx. 1" behind the rear axle. This is a '52 with all of the stock components. hope this helps.

 

Thanks 52merc is that 1 inch behind the center of the axle?

 

the center of the hole in the frame where the stops are bolted to, are about a 1/4"-5/16" behind the center line of the leaf spring thru-bolt hole.

I layed a 4' level edge on the center line of the leaf springs, then put a straight edge butted up vertically on the level, aimed up to the frame hole, then used another straight edge to measure to the frame hole. I got a 1/4" but with the thickness of the vert. straight edge, you could add a 1/16".

not sure how centered the axle is on the thru-bolt hole, but hope it helps.

 

havi If I put the center of the cross member a 1/4 of an inch in front of the bump stop hole it should be OK right.

 

center of the bumpstop hole, 1/4" forward...that would be the centerline, yes. Is the crossmember for the jag directly above? if so, yeah, should be good. I doubt 1/16" would be too noticeable anyway, my 2 cents.

I suppose you could tack weld it into place and measure the wheelbase afterward.

 

Thanks havi. This is giving me a headache.

 

Yes - 1" from the center of the rear axle to the center of the bumpstop. I dropped a plumb bob from the center of the bumpstop and mesured with a tape from the tip of the bob to the center of the axle.

 

well, the last post I made before I fell asleep said 1/4" forward. Well, today me being awake, went out and realized the 4' level was at an angle due to the arch in the springs. I put another level perpendicular to the 4' on top and leveled it out. That moved the straight edge forward another 1/4" So now I'm at 1/2". But the frame at that point which is slightly humped made the level bubble go the other way. So now I know it's more than a 1/2". So my guess would be 1" like 52merc says. My axle isn't there, but just the springs, too. Sorry if I gave ya another headache.

 

Hey Rusty, did you accurately place the front axle? If so, measure back the 114" (IIRC) and place the axle there. I find that dropping a plumb bob and making marks on the floor is the most accurate. If you don't have a plumb bob, try using a carpenters square from the floor.

 

Rusty, got home awhile ago and measured mine. Great name, btw. My bump stops are gone because I c notched the frame, but dropping a line from the center of the axle to the rear of the frame is 35 1/2" on my truck. To find the center of the axle, 8.8 solid in my case, I dropped a line from the front and rear of the axle tube, then found halfway between those two points. If my measurement works for you, here's what I would do. I'd drop plumb lines from the rear of the frame on both sides, then draw a line on the floor all the way across. I'd find the center of the jag axle, mark the line on the floor, then find a convenient spot on the jag axle to measure from, bolt hole, flat spot on the housing or whatever, and mark that spot on the floor. Find the distance from the axle center to your convenient spot and change the 35 1/2" by that amount. Use that measurement to position the axle from your rear of the frame marks. Position the axle according to your measurement, and when you get it correctly positioned, double check it against the axle center. When your sure you're positioned correctly, you can plumb bob from the axle assy up to the frame and mark that. Hope I made sense-Rusty.

 

Thanks fellas. I'm going to try it. Maybe the headache will go away. Usually goes away when the rod (welder) makes the first spark. I think the Jag IFS is in the right place.(I hope).