TR2/3/3A carburator decisions for TR3A

[velloti]

Group,
I want your advice. I will be rebuilding a TR3A engine with 87mm pistons. I have 3 choices for carburators:
1. Stock HS6
2. HD6
3. Webers DCOE 40s.

Question 1- Will the HD6s fit on the original intake manifold?

Question2- Is there anywhere to get just a manifold for the Webers?

Is there any advantage to any of these? While I am not restoring the car to strictly original, and I am not going to race the car, I would not mind seeing another 10-20 hp.

Jerry
1960 TR3A

id like to reply to a lot of this rubbish , i have been tuning webber carbs since 1964 , they are straight forward ,on a stock engine they will idle perfectly , now when you start uping the cam overlap they start to get fusy ,its all because of the low signal the idle sees and the position of the throttle plate to progression holes , no having raced with mikuni carbs for over 30 years they are darn good because its a modern carb but sorting them out will take time as you have so many jet combinations, far more than a webber , but they flow air , next why do you all ☼☼☼☼ around with out of date h6/hs6 su,s when s u made a far better carb the h i f 44 this flows more air than the hs series and it has a concentric float bowl far more effective, so me i would go on cost hif 44 are expensive the mikuni far less , webber well 4 of everything, its really finding someone who knows what they are doing when tuning

 

[Jayplum]

id like to reply to a lot of this rubbish , i have been tuning webber carbs since 1964 , they are straight forward ,on a stock engine they will idle perfectly , now when you start uping the cam overlap they start to get fusy ,its all because of the low signal the idle sees and the position of the throttle plate to progression holes , no having raced with mikuni carbs for over 30 years they are darn good because its a modern carb but sorting them out will take time as you have so many jet combinations, far more than a webber , but they flow air , next why do you all ☼☼☼☼ around with out of date h6/hs6 su,s when s u made a far better carb the h i f 44 this flows more air than the hs series and it has a concentric float bowl far more effective, so me i would go on cost hif 44 are expensive the mikuni far less , webber well 4 of everything, its really finding someone who knows what they are doing when tuning

Not sure what part of our conversation you feel is ‘rubbish’.

 

[Stevenry]

I had trouble getting my idle down and had run out of adjustment on the rear carb. I discovered one of my throttle discs was not centered and did not close all the way. Now centered, the idle is acceptable, though I still suspect a bit of wear on the throttle shaft and bushings.

Steve

 

[Jayplum]

Steve , You are correct while I had addressed adjustments to butterfly. I did not readjust the linkage. Did now and is better

 

[malbaby]

Yes, elevation change is where any constant depression carb shines. It doesn't matter a huge amount normally, but if you change elevation 8000 feet, that's going to throw out any fixed jet carb pretty significantly.


Understand that I have nothing against Webers - think they are excellent carbs (I'm running a total of 8 on my cars right now), it's just that they aren't always the best thing on the street, and far too many are stuck on otherwise unsuitable engines, and are never properly tuned.

They can be run on engines without downside when well set up - one example (of course that's one of my MG engines, not a TR....):

What is the engine out of....European Alfa or similar?

 

[Jayplum]

redid carbs this morning, she is idling down to 850.

 

[Stevenry]

Way to go. I’m sure it added a bit of sunshine to the day!

 

[Jayplum]

Absolutely all is good in the neighborhood

 

[billspohn]

What is the engine out of....European Alfa or similar?

MGA Twin Cam