F1Fan

Ouch!

F1Fan

Hi Kobie,

With Steeda Sport springs you probably want the LCA's in the stock location. The problem is that the BMR LCA relocation brackets don't have enough holes to get the LCA'sto sit atthe exact right angle with Steeda Sport springs and even the top hole is too low for anything except for a car with at least a 1.7"-2" dropat the rear. This is the problem I had with the BMR LCA relocation brackets, even with Eibach Pro-Kit springs and now the Steeda coilovers with 200# springs and the seats as low as possible and no pressure on the springs the LCA's are still angled downward. The BMR LCA relocation brackets are really only effective for drag racers due to the lack of adequate adjustment locations.

HTH!

Kobie

Crap. I had these welded on too. Should I just take them off or get the steeda ones?

F1Fan

Hi Kobie,

I know how you feel as I am faced with this same problem. I have been using the LCA's in the top LCA relocation bracket location and it is not too bad on Pro-Kit springs orthe new Steeda coilovers with the spring seats at their lowest setting but it's not ideal because the car still has some small amount of roll oversteer, not bad but still not as stable as I'd like it to be. I'm thinking I'm going to pull out my rear axleto give it a rub down with aScotchbrite pad or two before I paint it. When I do that I'm thinking ofinstalling a new set ofgears and either cut off the oldBMR brackets and install the Steeda brackets ordrill anextra set of holesinto the existing BMR brackets. It sort of depends on which is less difficult todo with the best results as the holes would have to be drilled very preciselyin an inconvenient location all while manhandling the axle around the shop. It might be easier to just cut off the darned things, clean up the original bracketsand weldnew Steedabrackets into place. Either way a real PITA job to do right.

HTH!

Norm Peterson

I haven't had the opportunity to crawl under the new toy, so I'm wondering how much (if any) plan view skew there is in the LCAs. The point being that with plan view convergence going toward the chassis, the LCAs can run uphill toward the chassis a little bit before the roll steer goes into vehicle oversteer. Some sort of limit would ultimately be imposed by how fast the axle's own roll axis shifts toward vehicle oversteer under braking (and upward movement of the rear of the chassis), but a tiny bit of uphill might still be OK.

I'm also thinking that it would be possible to drill the holes without having toremove the axle from the car. There's a little bit of tolerance that comes from the fact that this sort of attachment does not rely on bolt shear to locate the pivot. It's the friction developed from the clamping force, which explains the slight "sloppiness" of the fit of the bolts in the bushing sleeves. I'm sure that some sort of simple jig could be rigged to draw an arc about the chassis-side LCA pivots for fore/aft positioning and that you could use the inner sleeve to make sure that the hole through the other side of the axle bracket lined up correctly. Done carefully with the car weight on its wheels would mean that you would not be shifting the pinion angle any. And I think that you could keep thrust angle change to 0.05° or less (can't find a spec for this to check against, though).


Norm

F1Fan

Hi Norm,

WOW!Congrats! That's oneshinney newblack car you have there! Are you liking it? Well Norm you are about to enter the S197GT fun zone now, you know credit card debit! 8^)

I have not looked at a 2008 carbutprevious year cars once they have some milage on them all seem to have a very slight downhill angle towards the axleend of the LCA's, no more than a degree or two though it is hard to tell without getting it on a level old schoolalignment rack.

I don't know if I like the odds of getting the newholes drilled andperfectly aligned. There is not a lot of of room for error before thrust angle becomes an issue. Of course I guessif I can accurately find and mark thelocation to drill with the axle still in the caronce it's out and on the workbench the holes can get drilled reasonably straight. It still seems like a PITA to me though.

As to thrust angle Ford's Mustang manual specs a 0.5" maximum. They measure thrust angle as the error between the rear axle thrust centerline as measuredon a line drawn between the front axles. They do not give a number indegrees but I suppose you can calculatethe maximum errorbased on a 107.1" wheelbase using 0.5" maximum error Icalculate a maximum allowable angleof about 0.267 degrees or so.

HTH!

Kobie

New Steeda parts ordered!!!

Norm Peterson

Thanks, Chip. Yeah, it's a fun car even though I'll be taking it easy for a while longer. I'm still learning how to operate half of the features it has, and I DIDN'T get either the nav system or the satellite radio.There's a semblance of a mod plan already (past what's in the sig), just have to nail the specifics down in a few cases. I'll likely send some business Sam's way,though that'll be after I get a feel for the car in base stock trim on the 18's, make a few measurements, and run a few numbers. Some thingsI have a feel for, or at least a relative sense for what direction a change will make. Other things I have to come to understand via analysis. There's a car sized area in my driveway that measured via laser levelvery close to 1/16° off the horizontal plane in the camber direction and (IIRC) 3/4° in the caster direction, so if the weather on some weekend ever decides to co-operate . . .

<Back on topic>
About the relo bracket holes, I guess it's going to be a bit fussy of a job almost no matter how you go about it. But I figure if you can get the holes within 1/32" in the fore/aft direction, that only represents about 0.075° thrust angle if the LCAs are 48" apart and the errors are such that they add. Much better than about half of that is probably wasted effort based on the clearance between the LCA bolts and the ID of the bushing sleeves (not sure what sort of clearance there might be with a rod end). Unless you are using double-adjustable LCAs with both LH & RH threads.


Norm

Simon1

Okay so I have read the thread. I will be doing some brake work this next weekend and I figure since I will be there anyway, I should check the measuremtn you guys are talking about.

What is this .5" maximum error you guys are talking about. I assume that if mine was off it would effect my 60'. I beleive it's the relation of the axle to the chassis or the front wheels? Anyways, please explain. I have adjustable LCAs BTW.

Thanks.

F1Fan

Hi Simon1,

It is sort of hard to measure accurately on a garage floor, more of a thing you need to get printed out when you get an alignmet. Here is an image I found, the 0.5" measurement in the ford shop manual is the maximum as measured on the line between that line which represents the front axle. The thrust angle is actually a misnomer in this case as the angle is expressed in inches of error between the rear axle and at the front axle line.





HTH!