Desert86Roc

Do any of you know of idler arm / pitman arm combinations that are shorter than my IROCs? My current pitman arm/idler arm length is 6.5" center to center. I am looking for something that is 5.75" - 6". Some of you auto-x racers may have some ideas. With the shorter pieces I would gain the clearance necessary, and not change my steering angles (much).

Here is the problem: I have some clearance issues between my new Spohn K-member and the inner tie rods. Spohn claims that it is not a problem with their k-member, and they have sold "hundreds" with no complaints. My centerlink and tie-rod ends are all new Moog pieces. With everything installed, the clearance is so tight that I can not turn the steering wheel past the tie-rod sleeve (one of the Spohn heavy duty sleeves) even with the "cutouts" that were designed into the main bar of the k-member. The stock k-member did not extend as far forward as the Spohn unit does, so I did not have any issues before installing the K-member. There were no other installation issues (other than the spring perches not being wide enough for my springs) and all locating pins and bolt holes lined up perfectly.

Desert86Roc

bump... any ideas?

Guest

Send the defective part back.

Desert86Roc

Yeah...that was helpful. Thanks

Blue1989RS

I'd be interested as well. If I could find one that is 7-8" that would be awesome!

You would have to look into what other vehicles used this steering box. S10's for sure, maybe others. Follow that lead though and you may find something. I'll look into it as well and let you know.

Dewey316

If your local parts store workers are any good, they should be able to help. Take the stock parts down there, and explain what you are trying to do. (of course, if you have the typical dorks who can only look up a car in the computer, you are SOL).

Guest

The problem would be the pitman arm. Do a search recently, you'll find a post and see how common those are to buy. A parts store cant help you there. I know of 3 sources outside of GM for pitman arms and they were all outside of anyone's common stock so a parts store, at best, can only find the right idler application if there's even a different one to choose from (and I seriously doubt that). I think its going to be virtually impossible to find a pair of arms that are the slight length difference you want that are the correct angle as well and fit your steering box and idler arm mount spacing. Besides moving the k-member to a location where it clears, the only other option you have is what I already told ya. I know from looking at it Steve notched the thing to get clearance so as I suspected it was too close to begin with and with production tolerances you've had the joy of running into it firsthand. Maybe its not your car, but the part. Wouldnt be the first time. If someone can post up their measurement to the bolt holes and the notch for the tie rods from a common reference point maybe you can determine if its the new k-member or the car, rather than futzing around trying to locate a 1/2 size needle in a haystack and possibly messing up your steering geometry in the meantime.

Another reference point for measurement I can think of is the steering box mounting holes and idler mounting holes in relation to the k-member holes. I wouldnt think those would be off anything considerable but who knows.

Where's it hit? Got a picture? Inner rod about 1/3 of the way from the centerlink I suspect? I know of tie rods that are bent for clearance, that might be a better option and then you arent changing geometry.

Blue1989RS

Changing the length of the steering/idler arms WILL DRASTICALLY CHANGE the way the car steers. So I'm with madmax. Modding the tie-rods or k-member should be the way to go.

BT283

iTrader: (3)

I put an S-10 manuel steering box on my car and used the s-10s pitman arm, and if im not mistaken i believe it is a little shorter than a Camaros. But the pitman arm didnt change anything with the way the car turns, it turns great. Only thing it did was move the steering wheel. but that problem is an easy fix.

StevenK

iTrader: (1)

Dude, take some pictures of what you are talking about.

I recently did a LS1 swap and got the Hawks (pre-spohn) k-member. Long story short, I had to replace my pitman arm and weld in a bracket for a new (shorter) idler arm to pull all my tie rod/draglink/etc forward more to get it away from the K. I was hitting on the passenger side of the K.

If you search threads by me in the LS1 swap section you will see the post.

I havn't taken new pictures of it yet though, but basically we got parts used for race cars and modified my car to make it fit....and damn it was a PITA.

Desert86Roc

Ok...here are pictures of what is going on. I have been looking for shorter pitman arm/idler arm combos..but have not been able to locate them. Even called Federal Mogul (moog) and talked to their techs. My other idea was to modify a center link to take the "bends" out of the end...so that the link is completely straight across. We will see how that goes.

Image 1 shows steering all the way to the right


Image 2 shows steering as you start to turn back to the left just before contact.


Image 3 shows contact between the k-member and inner tie rod


Image 4 shows that as I force the wheel more to the left, the end of the tie rod can scrape by and gouges the powdercoating.


Image 5 shows where the steering will not go any further...at the tie rod sleeve.

shr00m

iTrader: (2)

Well it's good to know that going with the newer style Hawk's unit wouldn't have helped my and Steven's problems. I was able replace my Moog inners with some smaller units to clear mine.

Kevin D.

greezemonkey

iTrader: (14)

There is a simple solution to the problem, may not be what you want to do but it has worked for others, take the inner tie rods off the center link, remove the link from the pitman & idler and flip it so that the bends of the center link go toward the front of the car instead of the rear. Once you re install your tie rods the nuts will be on the inside, between the center link & K-member, now your tie rods have been moved outward out of the way of the tube cross member. It will change the toe drastically but there is enough adjustment to get it corrected.
Super stock cars designed by Ed Quay uses the centerlink reversed to drop a big block chevy down into the chassis 2 inches further than stock also.

That channel out of the tube for tie rod clearance is unique for sure, I have never seen anybody`s K-member notched like that before....you going with stock coils or coil overs?

shr00m

iTrader: (2)

That may work for drag racing, but for a car that you actually want to turn it doesn't work.

That was Hawk's solution for Steven and I, and we both had horrible results. Normally at center the tie-rods angle towards the rear of the car. As the steering is turned the center-link moves closer to the front of the car. This action puts the tie-rods in line with the center link giving you the most turning radius.

When you flip the center-link you now have the tie-rods pointing towards the front of the car at center. Any movement of the wheel just makes that angle larger. So the tie-rods never line-up with the center-link, which dramatically reduces your turning radius. You would have to run extreme toe out to get it back.

I had reset toe and my car tracked straight. It wasn't even too noticeable until I went to park and missed the spot I was aiming for.

Kevin D.

Neil

Does anyone know if this problem has been corrected or does this problem occur with all of Spohn's K-members?

Desert86Roc

Update: To all with suggestions, thanks. One of the suggestions was to change the pitman arm, but just changing the pitman arm is not an option, you have to have a matching idler arm. Almost impossible to find without going to a parts store and opening lots of boxes.

My solution: I ended up taking my old centerlink and straightening it (take the "bends" out of the ends). It came out OK, and looks like it gives enough clearance.

Another option I entertained, but am not going to do at this time: Convert to rack-and-pinion. Spohn's SBC k-member does not have a mounts for r&p, but the 4th gen k-member does. Maybe he will make it an option on ours? There are a couple of options and many different styles of rack to use. The easiest would be to use a 4th gen rack and just lengthen/shorten the tie rods to work with 3rd gen. You can even use your stock power steering pump. This setup will still save weight because you are removing the stock gearbox (heavy), pitman, idler & centerlink. This is probably what I am going to do long term, but dont have the cash right now.

BMmonteSS

Ahhh, sorry I didn't see this earlier. You need an idler and pitman arm off of a G-body. They are some where between 1/4" and 1/2" shorter than your F-body arms. I found this out when I swaped on an F-body steering box and ASSumed the pitman arm was the same length. It shoved my tie rod back into my crossmember on the G-body. I'm not positive that the frame bolt pattern of the G-body idler is the same as the F-body, but I bet it is.

Even if it works......it's not the best solution geometry wise. What it will do is decrease your ackerman. What ackerman is the geometry you get with the tie rods in a \_/ angle instead of a --- shape. What this does is steer your inside wheel further than the outside wheel in a turn. This may sound like a bad thing at first, but it reality it's a good thing and most street cars don't have near as much as they need, so decreasing it further is a bad idea. The reason for needing this is a bit complex and Caroll Smith describes it best in "Tune to Win" but basically it has to do with the slip angle of the tire, the unloaded tire needs to be turned further than the loaded tire to optimize your slip angle.

The second and more important change is your bump steer. Any time you move the inner or outer tire rod pickup point you are going to effect bump steer, maybe for the better but probably for the worse. This is something you'll just have to experiment with as it's way too complex to make generalizations about. I do know that G-bodies need the tie rod lowered and move towards the back of the chassis.....but as you know the front suspension is completely different than an F-body.

Also keep in mind that going with a shorter pitman and idler arm will quicken your steering up a bit, probably not much but it will effect it some.

Desert86Roc

Thanks for the info... What year(s) of G body should I look at?

From what I have read and looked at, the shorter arms should dumb the steering down, not make the ratio quicker. The shorter arms would not move the center link as far from side to side before hitting the internal lock of the gearbox. Thats my theory anyway.

Neil

Do other aftermarket K-members have this same issue? I called BMR and they say that they have not run into this problem with their K-member.

BMmonteSS

You are correct the G-body arms would slow the steerig down on an F-body....it's the other way around on a G-body, so I got my wires crossed.

cam406406

iTrader: (1)

does any one else have this problem with a spohn kmember? what did spohn say?

StevenK

iTrader: (1)

shr00m is exactly right. When you flip the drag link over (and in your case straighten it out) this will cause serious steering issues when you are turning, especially on a bumpy road.

Like I said, I had to get race car parts (moog) and weld on a new bracket for the idler arm. The new pitman arm had a larger hole than the stock drag link, so I had to have a little bushing machined as well.

I can't beleive that spohn hasn't worked this issue out, its really disapointing to see people are still having this problem.

I've also thought about the R&P steering upgrade, but the way I see it, why should *I* have to pay 1200 bucks because this part was built incorrectly? But then again, with my shorter pitman/idler I do not have the same turning radius I had before, in fact it almost feels like I have HALF of what I had before. It takes me 4 lanes to turn around :-(

On another note, even if I was able to get more travel from the drag link by using stock parts again, it still wouldnt work, because for some reason my same exact rims are now rub my frame rails.....

I seriously think someone didn't measure the clearences right when they were creating the jig for these k-members....

Fast92RS

iTrader: (2)

Does anyone else have a spohn K-member without this problem? Im considering buying the K-member from spohn. I have there front end rebuilt kit and there lower a arms.

Viprklr

iTrader: (5)

I just ran into this problem. Stupid MURPHY won't get off my back!