76 Spirfire Carb issues?

[Billy_Bob]

Just bought a 76 Spitfire, all original with 55K miles on it. Great condition...fires right up without a sputter. The PO says that he has tinkered with the carb some trying to get it set right but he said that he can get it to run right either on the low end or on the high end, but not both. He also handed me an ad from Ebay for a weber carb for it. But since he didn't seem too into carbs, I was thinking that maybe it just needs high altitude jets. It was originally bought in Indiana, but now resides in Colorado. My town is at 6500+ ft.

Thoughts? I would rather just replace the jets for $50 instead of the entire carb for $300+

 

[poolboy]

No need to change jets. The needle in the ZS carbs is tapered so adjusting the mixture is accomplished by raising or lowering the tapered needle into the jet.
The ignition timing may need to be changed, however to compensate for altitude.
We'll need a little more info to figure out what may be wrong with the carbs, if anything. In the meantime see what you can learn about the ZS carbs from this site.
Not the same size as yours but otherwise pretty much the same.
https://www.buckeyetriumphs.org/technical/Carbs/CarbsI/CarbsI.htm

 

[tomkatb]

I have lived with this carb for 30 years on my 77 spit.

First verify that the dizzy is 100%. Verfiy that the vacuum advance and centrifugal advance work 100% correct. A bad vacuum advance acts like this. Verify that you have the dizzy designed for that car. It makes a difference.

We rebuilt the Stromberg carb every 10 years. Very simple. The rebuild kit is $35-40(haven't bought one in 3 years), a can of carb cleaner and an autostore gallon can of carb cleaner to dip the carb in. It is not hard to do.

Last summer we put a pair of European HS-4's on the car. What a difference that made.

Compared to the Webber I think you would be disappointed for about the seme cost.

Larry

 

[Billy_Bob]

Thanks for the tips! The weather is now changing for the better here so I will start on it. I am going to take it for a GOOD spin first to get s baseline on the performance then go from there. I will definately check the timing and see if that helps.

OK I just went through the link you posted poolboy. WOW!! Now that is what I call a great write up. Thanks for that!