With coilover setups, why not relocate the LCA too?

[R.O.B.]

69GMACHINE, If I'm not mistaken, where the lower control arm is mounted now, if it were to be horizontal, it would bottom out. The arm is mounted on the inside of the frame rail, and horizontal would cause the arm to hit the frame rail.

Rusty67, you suggestion has alot of merit. I have power steering by the way. And in my opinion, its way to easy. I don't want manual, but it should have more resistance to it, ie.. like my Trans Am did. It wasn't so easy to turn from lock to lock with say just my finger, yet I can do that with the Mustang. The Mustang needs more of a sport feel than luxury.

 

[Rusty67]

If you want less assist then you can put a larger diameter pully on the power steering pump. You can also put a more restrictive power steering hose in but that can cause premature pump failure or so I've heard.

Also, large/wider tires will make it tougher to turn so you might consider geting a bigger contact patch on the road =)

The power steering setup on the classics is something I just can't defend.

 

[R.O.B.]

Well, I haven't tried the smaller pully idea, but I have gone to a much smaller steering wheel, and am using 225/50 R15's in the front. This still is not nearly enough. I think I'll look into rack and pinon.

 

[Rusty67]

You would want a larger pully, a smaller one would run the pump faster.

You could just put an adjustable KRC power steering pump in and see if that gets it where you like it. If not you can still upgrade to R&P later as the KRC is recommended when using a rack setup anyways.

 

[R.O.B.]

Your right about the pully, my typo.

Thanks for the info on KRC, I haven't heard of them before, I'm researching them now.

 

[DK832]

To the first Q: yes the LCA should be operating just +/- around perfectly level on a strut coil over suspension to avoid the "inferior" camber curve these setups have.
Someone mentioned a K-member and that's exactly what I'm using on my new build. Get rid of the original crossmember, get an adjustable A shaped tubular LCA, bye bye to the strut rod and steering box and in with a Pinto manual R&P. Saves a lot of weight and gets close to optimum geometry for that kind of setup. I'm using a special road race version from AJE: 64-70 Mustang The shock tower gets an adjuster plate and reinforcements as mentioned.
Just on a note, this is mostly a track car that's streetable and it's going to have hard suspension with short travel. As long as the travel is kept short I personally am having a hard time confirming that a strut setup is inferior to the classic geometry UCA/LCA. My current ride is fully modded with Global West UCA, boxed lowers, OTP roller perches, Rosehill Performance strut rods, PU bushings, adj. SPAX gas shocks, stiff springs etc.

I have to question if there is a universal "best" suspension, it really depends on driving style/needs and taken from that on suspension travel, stiffnes, caster/camber/toe settings etc etc. I hate driving with 750lbs springs and 3° camber on the freeway but love it on the local short, twisty track. A soft sprung 0.5° camber setup is smooth on the street but kills the tires in 2 laps.

Just my 2c (€)!

View attachment 295447

 

[fast_back_gta]

Hi!
Exactly why did you go with this setup, as your current one sounds pretty nice?
Are you in need of more engine compartment space or something like that?
Do you have R&P with your current/old setup?
Thanks!

 

[R.O.B.]

Everyone, I think I have the answers to my curious questions.

This link talks about r/c cars, but the principles are the same:

RcTek - Radio Controlled Model Car Handling - Camber Angle Basics

Just follow the links on the left to learn all.

This link gives you a moving input of the control arms. This will help explain if moving what where will do:

http://www.racingaspirations.com/suspensiongeometry.php

This will do the same, except with struts:

http://www.racingaspirations.com/macphersongeometry.php

Hope this helps everyone, this is sure helping me. I have a lot to learn, this will take a while to play with. (I'm at work)

 

[R.O.B.]

FYI, the last 2 links were working earlier today, but I can't pull them up now. Hopefully they will be working tomorrow.

 

[fast_back_gta]

Those links work now, and they're really cool! Thanks!

 

[DK832]

Hi!
Exactly why did you go with this setup, as your current one sounds pretty nice?
Are you in need of more engine compartment space or something like that?
Do you have R&P with your current/old setup?
Thanks!

The current setup stays, the AJE is for a new car.
And yes, I need a bit more space to run headers forward to meet the turbo. But the main reason is that the AJE setup saves a lot of weight up front and takes some load of those poor front tires. It also gives us the possibility to move the engine a bit rearward, again improving weight distribution.

The current setup is with an old but tight steering box. Looking forward to R&P!

 

[R.O.B.]

After playing with the strut model:
Racing Aspirations - a Formula 750 constructors diary (Fiat FIRE 1108) - MacPherson Geometry Calculator
I have concluded that when going with a strut coilover setup, lowering the lower control arm WILL make a big difference. I just left the model where it is, and played with the control arm mounting point. If I moved the suspension up or down 90mm (what about 3 in each way), the camber almost doubled with the control arm in the upper position vs a horizontal position. Now, I guessing, some camber is ok (like to help compensate for body roll), but to much will hurt the tire contact patch area. This sound like a good conclusion?

 

[fast_back_gta]

Yeah too much static camber hurts straight line tire contact and braking performance.

 

[bnickel]

you could also replace the stock power steering pump with a GM saginaw pump, there are quite a few conversion kits available, mostly for broncos but the pump brackets are the same for each engine so what fits a 302 in a bronco will fit a 302 in a mustang, you will need to have hoses fabbed or find some kind of adapter fitting most likely but that's kids stuff to do.

if you get an Opentracker, Maier racing, Global West, etc. "re-aligned" or Negative Roll/negative wedge upper control arm and lower the pivot point the appropriate amount you change the tilt of the tire in corners from tilting out to tilting in.

the biggest drawback to suspension geometry on the early mustangs is actually in the spindle not the suspension at least once you change the pivot point of the UCA anyway. currently nobody is making an aftermarket spindle with improved geometry but you could possible adapt a Wilwood Mustang II "Super" spindle which has a lot geometry improvements over a mustang II spindle and some over a stock early mustang spindle.


there are all kinds of low buck big brake kits available using late model calipers and rotors as well.

 

[fast_back_gta]

Hi, do you have some more info on that MII spindle?
Thanks!

 

[R.O.B.]

bnickel,
Please explain what it is about the spindle that is bad. To tall? To short? Bad steering arm? This is one area where I really don't understand alot, and want to learn.

 

[bnickel]

a big part of it is the spindle pin location, ideally it would be located higher up in the knuckle, effectively lowering the car and also allowing wider wheels and tires. the scrub radius isn't all that great either if you are running a wider than stock wheel/tire combo and the tie-rod location isn't ideal if you have converted to a rack and pinion setup.


you can see the wilwood spindle on their website, it's really designed as an improved replacement for a mustang II application but could be adapted to the early mustang with a custom steering arm but again it's not ideal either, IIRC it had something to do with caster, i'l have to try and find it in my collection of suspension information but it might be easier to do a search for wilwood spindle on www.corner-carvers.com and it should be relatively easy to find.

 

[R.O.B.]

Is there any other "factory" spindle that would be better? I remember reading something last week online about a versalies (correct spelling?) because of the length, is this correct?

 

[bnickel]

no unfortunately there isn't a factory spindle that would be any better. the lincoln versailles and granada spindles are basically identical, functionally, to a 70-73 mustang disc brake spindle and other than than the spindle pin diameter and tie rod taper size they are the same as the 68-69 mustang disc spindles. about the only realy difference between a versailles spindle and any of the others is the size of the lower ball joint which is much larger on the versailles than any of the others including the granada spindle.

Fatman Fabrications has a dropped spindle based on the granada piece but i've heard that it changes the track slightly and pushes the wheels further inboard which can result in the wheel/tire rubbing on the lower ball joint and steering arm, not sure what size wheel was used but one guy used the same wheels he had previously with stock granada spindles and he said his wheels started rubbing in those places after the fatman dropped spindles were installed. so that makes that spindle questionable at best. i believe it is also either a cast spindle or a fabricated spindle (memory is slipping) which could throw another wrench in the works as well.

 

[fast_back_gta]

Hi bnickel,
I've glanced at those wilwood drop spindles, and at standard MII spindles too for that matter.

It looks me as if the MII uses a front steer rack and spindles, is that correct?
If one were to use the MII spindle in an early mustang you have to place the r&p in front of the axle (assuming you'd use a r&p).

Would it be possible somehow to use the MII spindle with a rear steer rack?
Could'nt the spindles be swapped left for right, so the spindle arm ends up pointing rearwards? or would that throw everything off?

Also, It looks as the wilwood spindle uses bolt on arms, what if those were either flipped or changed from side to side, also meaning they end up pointing rearwards?

I'm really no expert at this, as you've might allready guessed.

here's a link to what I'm working on:
Mustang -69 sportsroof project pictures from friends & fun photos on webshots