Thread: IFS alignment, best way to...

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I am getting ready to put my pinto ifs under my '48, I preped the frame today. As far as I know, you would level the frame front and rear. Center the spindle in the fender well(Pre-Marked), making sure that the center of the spindle is the same distance up or down from the top of the frame on both sides. Then cross measure from the inside rear corners where the new ifs meets the frame and the rear inside corners of the frame.

If I am doing this wrong or am missing an important step some help from you all would be most appreciated.

I am really excited to get on with this part of the construction and get the chasis rolling again....Thanks all.

Did you get a package engineered specifically for your car?? Make sure you check ride height and tire clearance on turning. Also check your anti-dive angle on the upper A-Arm, should be about 5 degrees. Test fit and tack everything before you finish welding any of the peices. No idea what components you have, hope this helps you.

Thanks Dave, the 5 degree setting I was unaware of. I am using a stock componant right out of a 75 pinto. What would be the best way to measure or check to make sure I am getting that 5 degrees?

The anti-dive is determined by the angle of your upper A-Arm at ride height. The front of the upper A-Arm should be 5 degrees up, best measured with an angle finder and protractor.

Very good Dave, I have those measuring devices. Is it critical that this is done at ride height, in other words what the measurement would be with all the weight of the car on it? Or is it more of a measurement of stance? In other words since I want the car a little higher in the rear than in the front, this will put the frame at a slight angle. I would need to measure the 5 degrees from that angle right? Sorry if I am being too inquisitive but it is very important to me to get this right. I will be driving this car for a long time.

It is a measurement taken at the finished stance of the car, which is of course determined by the weight. As long as you can duplicate the stance of the frame, it doesn't matter what height the car is at. Before you finish weld anything, do a quick check of the caster and camber as well as verifying tire clearance on the frame and the fender.

thats great Dave, thank you very much. If it helps make the car handle better and be safer I am all for it. I appreciate all the help you have givin me, I hope that some day I can return the favor.

I should be after it this weekend and I am ready to get the car back on the ground. Time to see it rolling again!

Hi, Interesting topic!

Dave, I read from somewhere that the Caster angle should be same as the upper A arm angle
Is this 5 degrees angle you mentioned good for the original Pinto / MII IFS or is it good for aftermarket IFS that uses MII measurements? (Maybe for both?)
The KPI angle is 10 degrees in MII/Pinto

I've been away from this forum for some time so if there has been other instructive discussions about IFS's, please let me know!

- Jani -

Originally posted by Streets
Jani
http://www.clubhotrod.com/forums/sea...der=descending

Streets, thanks!

Seems that I have my comments on every thread about I.F.S's ???

People, if you have made and/or created your own I.F.S upload some pictures/information here.
I will when I've got something concrete!

- Jani -

here's a pic of the Merc with IFS

OOPs, sorry brick, didn't see this one earlier.

If I'm not too late, first things first. Double check the frame for square over it's entire length. Do a diagonal measure from corner to corner, front to back. THEN check the front frame section as a precaution.

About the ride heighth thing. First thing to keep in mind for the anti-dive, and all the alignment settings to work out is that the lower control arms be parallel with the ground at static heighth. The way most folks do that is to take out the springs and shocks and put a piece of allthread through the shock mounts. With the spindle in place you'll have the proper spacing between the upper and lower arms, then adjust the nuts you put on the allthread to have the lower arm parallel to the deck. Then you can move the crossmember setup to the chassis that you've got positioned at the attitude you desire. Depending on how low you want to go will determine if you mount the crossmember to the bottom of the existing rails, or if you have to notch them and "bury" the crossmember some. About this time some begin to wonder how this is all gonna be affected by the weight of the engine, trans, rad, etc. Doesn't matter. When all that stuff is in the lower control arms still need to be parallel to the ground, so you "adjust" that with spring heighth.

Then it's the stuff you've talked about above, double checking the wheel base, square to the frame, level across, and fitting the sheetmetal to make sure that visual and measured work together.

Oh, and assuming you're using the stock strut rods, the mounting to the frame needs to be stout. As has been noted here before, it's preferable to make the bracket by sandwiching two pieces together rather than trying to weld one thick piece to the relatively thinner rail stock.

Thanks Bob and Dave for all the great advice. I have a real good idea now of what has to be done. Our bead blaster is getting repaired so as soon as I get everything ready I'll get it done. It is looking like I will be cutting up into the frame to achive the ride hieght I want. The top a-arms will probly be just above the frame like in that pic from the merc.

Bob you lost me alittle when you discussed the strut rod attachment to the frame. I was planning on just makeing a gusseted L bracket to attach them to the bottom of the frame but you are saying that may be too weak that way?

If I run across any snaggs, I hope that I can come back and ask for help.

Once again thanks for the help, you guys have been great.

Sounds like a near bullet proof system to me, Tech. What did your bumpsteer end up being??? I am using a set of narrowed arms (5/8") on the Ranchero, so I think I am going to have to try out your system on it. Thanks for such a common sense solution, I was about to start building new fixtures for what will be a one off set up.

Originally posted by techinspector1
I thought someone would have comments on this????????

How about; You're too smart for me!!

Richard, that's probably as good an explanation for home fabbing an independant front as I've seen. I think it's particularly useful when starting with thin air for the build up. With a fully intact front assembly like it sounds here, I'm not sure that keying off the crossmember wouldn't accomplish the same results, as long as it's in it's original configuration. (meaning no "collision" damage or hokey, homebrew modifications). A key point to carry away from your posting though is the need to establish a reliable datum surface from which to do all the measuring and setup.

Dave, don't forget to shorten the ends of the steering rack tie rods or you'll never get it to toe in!!

I just went through all my pics of my new frame & MII crossmember for the IFS. I did not use anyones kit for this project I built everything from scratch. However, I did have a frame with a Heidts MII crossmember I took measurements from. The new IFS is based on a Hortons Evolution IFS and uses Kugel upper and lower control arms. I over killed the lower crossmember which measures 4x4, I could have easily gotten away with laying a 2x4 rail flat, 4" wide x 2" high.

When building the front crossmember and vertical towers for the spring hats, coilover shocks or air bags ( whatever you're using ) lay the lower crossmember and vertical towers back on a 5 degree angle. Everything you do now with your upper & lower control arms will automatically be at a 5 degree rake. Drill the holes in the lower crossmember, add bushing stock for the lower a-arms bolts and mount the lower control arms. The length of bushing stock and bolts will depend on whether you're using stock MII lower arms or tubular arms. Don't weld the bushing stock in at this time, let them slide freely in the crossmember. Wait till you've mounted your upper control arms and get everything properly aligned before welding the lower bushing stock in solid.

The 5 degrees for the spring hats, coilovers, etc. is also predetermined now from the vertical towers 5 degree lay back.

Take a look at my frame build on my project site, go down to the bottom of the page until you reach Aug 22/03 date and the frame build starts there. I didn't take any side view pics, but there is a couple taken at an angle and you'll be able to make out the 5 degree rack on the crossmember.
http://www.angelfire.com/super/1950bulletnose

I'm not very good at explaining tech stuff. I hope this helped.