Ford 9 " jig

[SRT17]

I am looking at building a jig to build my 9" for a monty..... What angle does the housing (on the front) need to be to get the right pinion angle when welding the spring perches. Thanks...

[SRT17]

Anybody???

[drivingexcitement]

If you dont know what pinion angle you want, and how to achieve it, you should probably pay someone to jig your rear end for you.

[gottaloveit]

i have been watching this post, hoping someone would awnser knowledgably, because i'd like to know at what angle would be the best to build a jig for the same thing. or at least, other's opinions on the matter.


i guess a dumb@$$ trying to be a smart@$$ is all you/we get.

If you dont know what pinion angle you want, and how to achieve it, you should probably pay someone to jig your rear end for you.
if you don't know how to awnser someone's question, you should probably let someone else reply.

[3dracer]

Anywhere between 5* to 8 * with perches level, is a good starting spot.

[hammond]

7 degree (pinion) is what we set most at

[DaveBauerSS6]

i have been watching this post, hoping someone would awnser knowledgably, because i'd like to know at what angle would be the best to build a jig for the same thing. or at least, other's opinions on the matter.


i guess a dumb@$$ trying to be a smart@$$ is all you/we get.

if you don't know how to awnser someone's question, you should probably let someone else reply.

I've been on one side of this type question.

Yes, a simple X to X answer is what is requested.
But, Driving's answer is good information for doing the whole job. If you don't know the angle range, it could be assumed that he doesn't know the rest.
Driving's answer wasn't the only one, others answered as well. The guy wasn't left hanging.

I think the next question for his reply is why? And if Driving is the man he'll answer / explain the other concerns in doing the job.

We all participate on this board and even when you don't agree with the delivery or the answer, you can learn from it.

Best of luck in 2012.

[DaveBauerSS6]

I am looking at building a jig to build my 9" for a monty..... What angle does the housing (on the front) need to be to get the right pinion angle when welding the spring perches. Thanks...

I understand this is a Monte Carlo and a 9 in rear. When you say spring perches did you mean control arm mounts? On stock monte control arms, I mounted the brackets on the rear at 4 degrees. There is little pinion loss on my car and I feel there is a HP loss to run too much more than that.

[DaveBauerSS6]

I didnt reply to this post because coil cars dont have perches, those are on leaf spring cars. Also my answer would be like drivers above..

I didn't understand the question and I ASSUMED in California all Monte Carlos are coil cars. LOL

[SRT17]

Yes it is a coil spring car. I have a stock rear end under the car now. I am putting a 9" together to swap out as I get time and money. It is a 3-link. It is not as much a jig for location of parts, but a fixture to hold the housing in position as I weld to it. I am going to measure off the stock one for position on the spring perches and control arm mounts (left to right) off center line. It has stock control arms on bottom now. The 9" will have rods with heim joints. I understand it would be easier to have someone else do it, but I like to do things for myself. With advice....LOL..Thanks

[DaveBauerSS6]

Yes it is a coil spring car. I have a stock rear end under the car now. I am putting a 9" together to swap out as I get time and money. It is a 3-link. It is not as much a jig for location of parts, but a fixture to hold the housing in position as I weld to it. I am going to measure off the stock one for position on the spring perches and control arm mounts (left to right) off center line. It has stock control arms on bottom now. The 9" will have rods with heim joints. I understand it would be easier to have someone else do it, but I like to do things for myself. With advice....LOL..Thanks
This new info is helpful. Is the top bar (3rd link) a solid bar or a spring or biscuit bar? Solid bars dont have as much pinion angle change as the others. The pinion angle would be different.

[SRT17]

Solid.......Thanks

[TeamGRT12x]

Easy, get 2 Gingerbread 2 link mounts, like what Dirtworks uses, bolt them to the housing, get yourself 7 degree's of pinion angle and weld them up. Nothing too difficult. Most of the time, the shock mounts on the bottom of those mounts are square, and we just set the housing on the ground, with the mounts holding the rear end up and weld them up. Like I said, 7 degree's and you will be fine. That should put the mounting location of the trailing arm directly below the centerline of the axle with 7 degree's of pinion angle.

Then from there, depending on your rules, you can either weld a stud off the top of the housing or just weld the spring cup directly to the housing.

[drivingexcitement]

There is a lot more to a rear end than pinion angle. You need to take into account the driveline angle. Rear end lead and trail. Center the rear end of not. Trailing arm angles. Angle of the upper arms. There are too many variables to just start building your own rear ends. If youre rear end is not correct you car wont work properly and you run the risk of breaking driveshafts, transmissions, gears, and wrecking the car.

[dirty white boy]

car needs to be at ride higth with bar angels set right,..then shaft an pinion angels can be figured,..any thing else might not work right an be chunk'in shaft an braking $part$
also need to have good idea how much upward motion your pinion will have an considered into your calculations...

[SRT17]

How do companies mass produce rear ends? They must have a standard position for everything... To me, the only thing that can't be changed is the angle on the spring seats and the control arm mounts after welding them to the housing. Everything else will have adjustment in rod ends...

[steveshawjr]

if your running a 9" why not just get the bolt on mounts get it all setup i nthe car get you angel and tack weld them all up in place so they cant move than if you want to make a chage you could just grind off the tack weld and redo it ?

[TeamGRT12x]

A 2 link is very simple to set up, don't make it harder than it is. Driveline angle? The ride heights do not dictate pinion angle. If you get the rear end set up correct, with the mounting points straight below the axle centerline and 7 degree's of pinion angle at this point, nothing is "off". It is a 2 link not a stock 4 link.

Obviously you have to mock the rear end up in the car to get the rear end set in correct, but that's typical. At this point, if you don't know what you are doing you should probably have someone set it up for you or give you a hand in the shop. I would have drivingexcitement come over, he seems to not know what he's talking about

[DaveBauerSS6]

At this point, if you don't know what you are doing you should probably have someone set it up for you or give you a hand in the shop. I would have drivingexcitement come over, he seems to not know what he's talking about

I reread his posts and I didn't see anything wrong. Could you explain.

Interesting you both said the same thing about getting help, just at different times..

BTW I agree with both of you; get help, it will save time in the long run.

Thanks.