Lower Control arm hits header . . . are you freaking kidding me??

[siggyfreud]

Well the new LCAs arrived (stock replacements), and guess what?!? They hit my brand spanking new headers, which I bought because my old headers which I had recoated wouldn't clear the fancy new motor mounts!



I guess my only option now is to shift the engine back an inch for more clearance, which means yanking it and drilling new crossmember/frame holes. Unless anyone can think of another idea . . .

[cArNaGe]

Is it possible to spin the bolt around? The head may give you more clearance. Maybe some other type of fastener with a small diameter?

[siggyfreud]

Originally Posted by cArNaGe

Is it possible to spin the bolt around? The head may give you more clearance. Maybe some other type of fastener with a small diameter?

No, because it's a threaded shaft that has to have a nut on the end. With it fully torqued the nut MAY clear the header, but the shaft threads will only have millimeters worth of clearance. Would that be enough?

[sigshooter]

Slightly grind the nut once tightened and slightly massage an invention in the header.... Should give you ample clearance

[siggyfreud]

How much clearance do I need realistically? Is a few millimeters enough, or will the engine torque enough even with tight mounts to stress the headers and bolt holes in the aluminum heads.?

[Captainfab]

That side of the engine will lift when under power. What I would do is replace that nut with a thin nylock nut and trim the excess shaft off.

[B_Bob]

How about modifying your lower control arm shafts to be further forward. Saw this thread a while back. It would also help center your wheel in the well.

http://67-72chevytrucks.com/vboard/s...d.php?t=501241

Here is a side-by side shot of the factory locations versus the new locations. The upper shaft is the factory location, the lower shaft is the new location.

[siggyfreud]

May try that, but hoping that shaving the shaft end and nut a bit will work.

[tincan1966]

Unfortunately that is a common problem with long tube headers. same as with the '67-72's.
I would suggest doing the LCA shaft relocation. Three reasons: 1 you'll achieve the header clearance you are after. 2 it will help center the wheels in the wheel opening for cosmetic reasons, and 3 it'll help with caster, which will make the truck drive better.

I did this on mine and it is probably the best, and easiest modification you can make to help the steering. I just turned my shafts 180 degrees and drilled a new hole 1" farther back(center to center of the holes)

[Woogeroo]

Old trucks are fun.

*smIrk*

-W

[tincan1966]

Originally Posted by Sharps40

Not me boss....that there is prime SmasherWacker opportunity! Dent that tube!

Of course, a quarter inch to half inch steel shim under the legs of the engine stands might just do the trick......

Why deliberately damage a brand new part just to hit something with a hammer?
No sense in ruining the finish on a brand new set of headers

Take your time and do it right. The solution is simple and no damage to parts.

[jjzepplin]

Originally Posted by B_Bob

How about modifying your lower control arm shafts to be further forward. Saw this thread a while back. It would also help center your wheel in the well.

http://67-72chevytrucks.com/vboard/s...d.php?t=501241

Here is a side-by side shot of the factory locations versus the new locations. The upper shaft is the factory location, the lower shaft is the new location.

^^^^^^^^^^^ THIS~!
This is the best answer for your problem.
As stated you will have many benefits from this mod and you will never have this problem again. Oh and it's FREE!!!

[siggyfreud]

So no issues with spindle or ball joint alignment doing this?

[chevy_mike]

Likely if you had the stock type arms with the metal bushings instead of the '73 and later arms, they would likely clear or would be very close to clearing. Here is what the '63-'72 arms would look like.



When you start part swapping other year parts, you can run into all types of weird problems.

[siggyfreud]

Yeah it looks like that style would clear with room to spare. I think I'm more ticked since I already bought new headers to solve another clearance problem .

So long as redrilling the mounting position on the shaft doesn't mess up the mounting to the spindle or steering, it seems like that might be the best solution.

[siggyfreud]

Just read through the attached thread on the LCA mod. Looks interesting. A few people seem to really like it, though some had concerns about shock mounting, as well as the coil spring being at a slight angle. Any thoughts on that? It appears the added caster is noticeable on the highway?

[bama63]

Originally Posted by Captainfab

That side of the engine will lift when under power. What I would do is replace that nut with a thin nylock nut and trim the excess shaft off.

x2!

[tincan1966]

Originally Posted by siggyfreud

Just read through the attached thread on the LCA mod. Looks interesting. A few people seem to really like it, though some had concerns about shock mounting, as well as the coil spring being at a slight angle. Any thoughts on that? It appears the added caster is noticeable on the highway?

At stock heigth, the amount of shock mounting angle change is minimal, same as for the spring- no ill effects at all.

I have 1 1/2 coils cut from the front springs, no problems at all with the springs. The shock angle could stand to be a bit better I suppose, but mine is still on stock location and working fine.

[siggyfreud]

Originally Posted by tincan1966

At stock heigth, the amount of shock mounting angle change is minimal, same as for the spring- no ill effects at all.

I have 1 1/2 coils cut from the front springs, no problems at all with the springs. The shock angle could stand to be a bit better I suppose, but mine is still on stock location and working fine.

Have you noticed an improvement in driveability? Planning on marking the LCAs and taking them to the machine shop today or tomorrow to have them drilled for the forward location.

Did you go 1" or .75" on yours?

[B_Bob]

Originally Posted by siggyfreud

Have you noticed an improvement in driveability? Planning on marking the LCAs and taking them to the machine shop today or tomorrow to have them drilled for the forward location.

Did you go 1" or .75" on yours?

Make sure to take pics. Would love to hear how it turns out for you as I am considering this mod myself.