Top Trunnion Mount

[Si Richards]

Hi all

Just some opinions on the top trunnion mounting point where it attaches to the wishbone. I'm trundling along nicely and am just on the pretty bits now but this just keeps popping into my mind and I don't know what's best. From all the pictures I can see there are no spacers fitted between the trunnion and the wishbone but when its tightened up it really pinches the U shaped bracket, although I believe its fine I just wandered what you guys did.

Thanks in advance.

Si

[Splat]

I've used SuperPro polyurethane bushes (from Moss) here. It's a tight fit with the supplied washers. Then simply tightened the nyloc on the trunnion link pin until it felt right. As you say, a little inexact, but it does the trick.

[Westfield 129]

I have used the urethane bushings as well as the standard rubber bushings. Both are pretty good, but I prefer the rubber, as they are actually a bit stiffer. I may try a set in Delrin.

Any tight fit can be remedied with a little bending. Installing washers (as with the Moss kit) will reduce the pinching, and makes for the best installation.

I tighten them to about 5 lb.-ft. (torque applied to the bolt head and nut to affect rotation after tightening a fresh nylock or castle nut and cotter pin). This is about where the nut/bolt feels "right" (to me, anyway). I would not tighten this point beyond 12 lb.-ft. on a fresh nylock. Everything works better when it can move freely, without rattles...

[Si Richards]

Thanks for the feedback guys as I said I didn't like the pinching so will fit some washers, the torque settings state 30 ft lbs but I thought this was a little on the tight side so will go with your suggestions.

Thanks again chaps.

Si

[Westfield 129]

I think that you will notice a definite improvement in ride and steering response and predictability once you loosen the suspension bolts a little.

[Westfield 129]

Tom Colby of Speedwell Engineering here in Southern California is offering delrin top trunion bushings for Spridgets.

He has them in offset drilled for camber adjustment, and center drilled, for Westfield 11s. As they are stiffer than the urethane and rubber parts, they will properly center the top trunion in the upper arm fork. Delrin is very smooth in operation as a bushing, and offers a small amount of compliance. Properly lubricated, they will last as long as the car. I have used delrin bushings in my other cars, and they have gone past 100,000 miles, even with hard competition use.

I have ordered a set for my W11 to replace the squishy urethane upper bushing, and I will be test fitting a set to the lower trunion mount.

There is also a lower trunion bushing as well. I have not yet fitted these to my car.

Cost for the upper bushings is about $50 USD, which is reasonable. The fit can be shimmed with washers to match your upper arm fork, and eliminate any bending.

I am also looking at Speedwell's tubular front anti sway bars, as they are reasonably priced, and of far higher quality than the poorly bent pieces that we have been getting from Westfield here in the US.