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TR6 TR6 Strombergs
- Thread starter BillS1
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poolboy
Yoda
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There are some differences. The 74 can be adapted, however.
The 74 has some vacuum ports, I call them "nipples" that no other year has.
The Throttle Bypass Valves on the 74, if original, has nipples that hold a vacuum lines to the Thermostatic Vacuum Switch, which I believe is not even present on later years.
Then there is that little device on the 74's rear carb that in some way activates the EGR valve. I have that disabled on my 74, so it certainly won't hurt to disable it on a later model.
As for the Throttle Bypass Valve's nipple. you could change out the valve entirely with yours OR just cap them off and see if you get backfire while decellerating. You may not.
Other than that I can't think of any other differences and I have both 74's and 75's right here to compare.
The 74 has some vacuum ports, I call them "nipples" that no other year has.
The Throttle Bypass Valves on the 74, if original, has nipples that hold a vacuum lines to the Thermostatic Vacuum Switch, which I believe is not even present on later years.
Then there is that little device on the 74's rear carb that in some way activates the EGR valve. I have that disabled on my 74, so it certainly won't hurt to disable it on a later model.
As for the Throttle Bypass Valve's nipple. you could change out the valve entirely with yours OR just cap them off and see if you get backfire while decellerating. You may not.
Other than that I can't think of any other differences and I have both 74's and 75's right here to compare.
TR3driver
Great Pumpkin - R.I.P
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There's a nice chart of differences at
https://www.buckeyetriumphs.org/technical/Carbs/CarbsI/CarbsI.htm
BTW, I'm pretty sure the TVS controls the vacuum retard (port on the bottom of the rear carb) for 74. And the TVS was deleted in 75. The external port for the bypass valves was deleted before 74.
https://www.buckeyetriumphs.org/technical/Carbs/CarbsI/CarbsI.htm
BTW, I'm pretty sure the TVS controls the vacuum retard (port on the bottom of the rear carb) for 74. And the TVS was deleted in 75. The external port for the bypass valves was deleted before 74.
poolboy
Yoda
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On the 74 there are actually 2 vacuum lines from the carbs going to the TVS. Yes, one does come from the bottom of the front carb. The other is a larger diameter line that interconnects the 2 Throttle Bypass Valves then procedes along the same route as the smaller line from the bottom of the front carb to the TVS. The TVS for the 74 actually has 4 nipples. One for the dizzy retard unit,2 for the vacuum lines I just described and one that can be capped or left open.
After 74, there were no TVS and the line from the front carb went directly to the vacuum retard on the Dizzy, if you don't count the factory installed "fuel trap" midway in the line
As I said, I have both right here in front of me; but the illustrations in the Moss catalog under "Emission Control" show the differences as well.
After 74, there were no TVS and the line from the front carb went directly to the vacuum retard on the Dizzy, if you don't count the factory installed "fuel trap" midway in the line
As I said, I have both right here in front of me; but the illustrations in the Moss catalog under "Emission Control" show the differences as well.