I have seen a car with the springs which compress the cups at the end of the drag link replaced by a bolt and locknut which screw into a nut welded into the end of the drag link cap. There is a bit of spring in the drag linkage caused by the cup assembly compressing and so I guess that this could give a more positive action under some circumstances. I'm not sure whether this causes any issues in practice though, does this mod make any difference? - obviously assuming that the rest of the system is properly set up and the castor is correct etc...
I'm also considering the options for a new drag link rod since even on my "best" one the holes for the 1/4 fixing bolts have elongated, meaning that the inner cup moves, no matter how well the thrust on the cap is managed. Has anyone made or supplied new rods?
Charles P Wrote:I'm interested in the answer as well Tom.
I'm also considering the options for a new drag link rod since even on my "best" one the holes for the 1/4 fixing bolts have elongated, meaning that the inner cup moves, no matter how well the thrust on the cap is managed. Has anyone made or supplied new rods?
Charles
It was a car at Prescott last year, it doesn't look like a difficult thing to do so maybe worth a try even if the advantage is debatable.
12-03-2020, 05:26 PM (This post was last modified: 12-03-2020, 05:29 PM by Steve Jones.)
I've seen a similar set up, Tom, probably on the same car at the same place as you. I have it in the back of my mind that someone on here (or the previous forum) might have done a similar modification although I can't remember who. However, does the bolt and lock nut replace the spring or is it used to compress the spring inside the cup/drag link? I'd have thought it might be the latter.
I'm certainly interested in making or obtaining a new rod. As long as suitable tube with the correct i/d and o/d was obtained, I can't see it would be too difficult to make.
Steve
Edited: I see from Charles' link, above, that Terry's been there, done that. Good enough for me!
Hi folks,
I have a set up on the Type 65
I tapped the end caps to 1/4 bsf insert set bolt with nut on thread and use the nut to lock the bolt is position.
The bolt should push against the thick bevelled washer inside the end cap.
You have to carefully set up so that the spring still does its job, the bolt just limits the travel of the cup.
I aim for about 2mm slack in all conditions, which means 4 mm total lost motion on the drag link.
I have been using this set up for the last 15 to 20 years with no problems without brazing.
I does sharpen up the steering under hard cornering.
This mod is pointless on a normal road car.
I may be teaching grandmothers etc, but I can imagine that a drag link needs to be made of something slightly more 'high tech' than straight 'off the shelf' tube. Having had to remake brake pedal push rods for other (marque) cars, I have always been advised to use 4130n tube that provides greater strength. Given the stresses that a drag link migt undergo, it might be worth considering. It is used extensively in the aero industry and a provider can be found here as an example..
It’s a brave man who posts a picture of a polished steering arm. Bob is going to get over-excited now. For a road car, I think the standard set up provides some needed compliance to cope with potholes and stuff. Track cars don’t have that problem and this mod certainly sharpens up the steering.
