Initial throttle linkage setup dual Strombergs '69 2+2

I am assembling my XKE without the luxury of being the one that took it apart. Linkage has been pretty straightforward so far and the initial rough assembly went good. Going through pictures the previous owner took during disassembly back in 1979, I noticed the car had insulators between the carbs and manifold. After installing, these affected the linkage travel which seem to be somewhat adjustable among the links under and at the end of the manifold but not the link at the bulkhead. To make it reach, it has the secondary throttle open slightly ahead of the primary. My instinct tells me to set the link at the bulkhead and adjust the primary to secondary links to allow the secondary to close but the limits of adjustment are almost maxed. Any tips at this stage would be greatly appreciated.

Mike

I can just get the secondary to seat if the small link under the carbs have just a few threads holding them. Is that typical or would an adjustable link be needed at the bulkhead to solve this? Thanks

Response may be limited as most here have probably done away with the secondary entirely.

Full removal, holes plugged, throat lined, etc. are the ideal approach but possibly only practical with the manifold off – however, there is a 5-minute trick courtesy of Peter C that gets you most of the benefit:

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That’s great and seems like a good interim fix. Thanks for the tip! I can upgrade the carburation down the road.

Mike

Unless you intend to live at 4000 rpm, and up, the dual Strongbirds, properly setup, work juuuuust fine.

Not as snazzy as the triple SUs, but entirely adequate.

I’m sure they’re fine. I’m just hungry to get this 12 year project finished to enjoy this summer. I purchased the car dismantled. I told myself I will not sit out another summer so as long as it runs moderately that’s a win for me. I understand your point and I would either like to eventually resolve the secondary setup during the off season or go to the next step.

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I recommend making a metal bushing for the bulkhead bracket (shown in your photo) to replace the rubber grommet. Mine failed within a couple of months and left a lot of slack in the linkage.

Last month I did notice a little up/down movement of the carb rod at the firewall bracket before it starts rotating so looks like I need a new bracket bushing too. In the mean time I just loosely tie wrapped the carb rod up a little so that it cannot move up/down easily before rotating. Jamie how did you make a metal bushing for the firewall bracket ? Seems like a better plan than the rubber type.

One thing I did years ago after replacing the firewall bushing and adjusting all the rod lengths and bell cranks was to cut off a cotter pin to put in the slot on the linkage arm between the carbs. Might be crude and not something you like but takes out all of the slop at that point at least on my car.


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David
68 E-type FHC

It was not easy because that bracket won’t come out once the intake manifold is installed. I machined a bushing with a shoulder, then cut it in half down the axis. Installed it and lockwired the two half together. I’ll post a picture tomorrow. It was a pain, but it works good.

It might well be that the insulators are incorrect. I would consider obtaining a new set from one of the reputable.

I replaced the plastic bushing with a bearing in the bracket to my carb rod bracket. Made a huge difference.

How does that set up accommodate torsional movement of the engine relative to the firewall under acceleration? I would have thought some compliance is required there to do that, as well as suppress vibration being transferred to the bulkhead.

I would guess that he has used a self aligning bearing which would work well in that application.

The one I used is like this.

Here is a picture of the bushing I installed.