How much HP from a pair of 40 DRLAs

[Chris bugster]

These carbs are so common and so relatively cheap second hand, that I was wondering what their limit was. I suppose the biggest choke that I have used in them was a 36 for a 2366 T4. I don't know how much HP it made, but judging from the 1/4 mile speed it ran in a very heavy 1303 (over 1000kgs with driver) with long gears it must have been making about 140-150hp. I think that the was more to come from the combination and it wasn't the carbs that were holding it back but rather the relatively gentle head work and 1.5inch exhaust.
The reason I ask is because in the ''small powerhouse'' topic MR JP managed 188hp with a 37 vent in a pair of IDAs. Should a 40 DRLA be that far off with a 36mm vent. I don't expect to make 188hp, but was hoping I could get 160 or maybe a touch more out of them.
What is your experience?

[Torben Alstrup]

I have never tried them on the dyno with 36 mm venturies, because I couldnt get the transition right. (They got the "IDF syndrome" of being late on the main circuit) But I have done some pulls with 35 mm venturies on varius engines.
2056 type 4 with good heads and cam,  153 hp.
2110 type 1, 153 hp.
2275 type 1, 157 hp.
2275 with update kit, 163 hp. (But gained the usual fuel mix problems in the midrange.)

T

[Chris bugster]

Thanks for all those examples, Torben
By fuel mix problems, do you mean that they went lean in the midrange to get the correct a/f ratio at full throttle?

[Torben Alstrup]

No, the other way around. It gets too rich in the midrange.

T