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charleyf
Luke Skywalker
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You could likely achieve the desired result by switching the needles in the present carbs.
Charley
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TR2/3/3A 1960 TR3A w/TR4 engine, fuel pump replacement
- Thread starter kodanja
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Charley
I have heard there are hundreds of needle choices to do that. Probably complicated to narrow it down to what you want?
charleyf
Luke Skywalker
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Not nearly as complicated as trying to get the best needle for a 2" SU on your car.
There are up to 14 measured positions on a needle. You just need to find the best combination for your use. Of course that would be by finding a needle chart and going from there. For example the normal needle for a TR3 is an SM. They call for a RH for a rich needle. I found a KD needle on a set of HS6's on a TR4 that was apparently raced.
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I am sure if you have 87mm or larger the carbs would be fine.Boils down to air flow velocity at idle
getting too low on smaller engines. It worked on MGB motors as long as they were full race and you
didnt care about idle (cause of the cams)
IMHO an 86mm,mild cam motor, would NOT see any benefit. Also the splitter area in the manifold
on a Tr3 needs a lot of work and a bit of heliarc to work well. Look inside of a tr4a manifold and compare.
Mad dog
getting too low on smaller engines. It worked on MGB motors as long as they were full race and you
didnt care about idle (cause of the cams)
IMHO an 86mm,mild cam motor, would NOT see any benefit. Also the splitter area in the manifold
on a Tr3 needs a lot of work and a bit of heliarc to work well. Look inside of a tr4a manifold and compare.
Mad dog
Offline
I'll second this. TRF used to sell "better" pump rebuild kits... not sure who might carry the kits? A rebuild of the wear items could solve your problems.
Also TRF sold a "better" fuel pump made in Italy. I paid $200 for mine, vs $35 from Moss - and worth every penny. (My pump was (1) not original, and (2) beyond saving - thus the replacement.) Again, not sure who supplies these today? The A/C pumps were used on a bunch of cars, I'm sure there is another supplier??
WORD????