Wedge TR7 SU Conversion

[Alabama_Hokies]

I am in the process of changing out the Stromberg's to SU's on the TR7. I have a question related to the throttle linkage between the two carbs. There is a bar that joins to two carbs together. When put in place it is extremely tight, almost binding and I see no adjustment. The linkage and carbs came off of a British TR7 and it is tight when put on the original British manifold.

Question: Is there an adjustment? Is is supposed to be that tight?

 

[philman]

when I converted mine to SU's I used an intake manifold off a '76. I don't recall the linkage being tight. I tried them on a manifold off a '79, but I couldn't get the linkage set up right and had trouble with the piping.

 

[Alabama_Hokies]

I am using the original 80 manifold. However, I have the manifold that the carbs were "supposed to" have been on originally and the linkage is tight there as well. I say "supposed to" because they were not mounted when I received them. That manifold will not fit my head. At least I don't think so. I can get all the linkage to work, it is just that the bar that goes between the throttle plates almost binds. Was thinking I should shave a little metal off to make it shorter, but wanted to make sure.

Thanks for replying so quickly.
BTW- do you like the SU's on the 7?

Thanks!

 

[tr8todd]

I had a TR7 with SUs sourced from an early 240Z. Combined with an uprated cam and headers, it was pretty quick for a TR7. It would take a stock TR8 0-60 but after that the TR8 would just pull away. I had to weld together fab up several pieces from the Datsun linkage and the ZS linkage to make it work properly. There were little adjuster screws with springs on the levers for each carb.

 

[Alabama_Hokies]

The adjuster springs, those were shaped somewhat like a "z" that would allow for any misalignment and stress in the connection, correct? I have seen those and have them on some other British car (although I don't remember which). Unfortunately this is a solid shaft between the carbs with the only adjustment I can locate is "rotational" nothing longitudinal.
Looking forward to getting these mounted and getting rid of the Strombergs.

Thanks

 

[philman]

I went to SU's because I was unsatisfied with weber down drafts and SU's are so easy to work on. My FHC is out of service right now because I broke the windshield and I've been using my dhc auto crossing lately. But it was a nice improvement over the ZS's and seemed quicker on the throttle. I have a stock cam. I'll try and go out and get an image of my linkage.

 

[Alabama_Hokies]

That would be great, thanks.
The post on the "TR-3 Carb Linkage" I believe is the kind described by tr8todd.

https://www.britishcarforum.com/bcforum/ubbthreads.php/topics/867871/TR3_carb_linkage#Post867871

The picture of the two carbs mid way down shows the linkage with springs. Mine is a solid bar and I'm just trying to determine how to adjust.

Thanks for the assistance.

 

[WedgeWorks]

Todd & Crew I still have the copy of Todds original I used for the Datsun 240Z carbs on a TR7. It is not very wide and has on each tab an adjuster screw.

 

[Alabama_Hokies]

The tab on the adjuster moves primarily rotationally. Is that what you are talking about? My problem is the length of the bar itself. When placed in the throttle plate nuts it binds the system. I'm I missing an adjustment that shortens the bar? Do the nuts that hold the throttle allow for adjustment?

 

[tr8todd]

Probably need to cut and reweld or grind down the ends a little. Bust out your fabrication skills.

 

[Alabama_Hokies]

Yea, that's pretty much what I thought. Just wanted other opinions cause as easy as it is to remove metal... kinda hard to put back

 

[Alabama_Hokies]

Update- Problem fixed by a little judicious use of the file on the bar. Appears to be working fine. Now on to tuning.

Thanks for all the input.

Dave B