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-   -   Carb questions: Favorite and Sidedraft (https://www.rx7club.com/1st-generation-specific-1979-1985-18/carb-questions-favorite-sidedraft-155639/)

unreality 02-05-03 07:38 PM

Carb questions: Favorite and Sidedraft
 
I've been doing a lot of N/A 13b research, and I think if I was ever going to throw one together, I'd definitely carburate it. I don't know why I'm more comfortable using a carb than I am using EFI... I guess it's the complication the ECU brings. In any case, I've been looking at the wide variety of carbs that fit the 13b... Dell'orto, Holley, Weber, and Nikki of course...

If you guys had access to any of these carbs, what would you choose to use, and how come? I mean, I've read in a few places that some of the carbs lack a vacuum tube for distributor advance? Others don't like being started cold?

Also, do sidedraft carbs have any advantage on a motor as compared to downdraft carbs? Downdraft carbs seem much more common...

Thanks for the help guys. ;)

jutny 02-05-03 07:50 PM

well, i have a Dellorto 48 DHLA... which is sidedraft, and i like it.

the reason to go sidedraft is that it's cheaper than downdraft... because downdraft generally limits you to a holley (4bbl) or Weber IDA (progressive)... and webers cost a LOT of money.

DCOE's, DHLA's and Mikuni's are all cheaper alternatives (sidedraft) that perform as or almost as well.

SilverRocket 02-05-03 08:00 PM

48DHLA here too.

The Dell is probably a slightly cooler choice than a Weber DCOE (albeit not with as good parts availability, and more DIY work required), but not quite as good as a Weber IDA (albeit cheaper).

One problem with the sidedrafts is that with a ported motor, the standard u-shaped manifold is not ideal as it doesn't flow well at really high rpm.... it's not a big limitation, as there are alternative manifolds, but it requires a bit more work to set up that for a stockport.

Personally, if I were starting it out and really wanting to do it right for a ported 13B, I'd probably go with a Weber IDA.

Conway 02-05-03 09:53 PM

I am in the process of installing a 48 DHLA, so I can't tell you how good or bad it is, but I had to find some parts when I was rebuilding it and it was't really too hard to find them. I also like carbs. I guess I just like how mechanical they are. It just makes sense.

Conway

680RWHP12A 02-05-03 10:32 PM

weber carbs are the best!!! not too expensive if you know where to go!;)

RoTARY-ReX 02-05-03 11:09 PM

Yea like 680 said, if you know where to go, you can get a very good price... :) I chose to go with a Weber 45DCOE... I am going to get it in a few days actually... (If it made the mail today) :)

bliffle 02-08-03 01:02 PM

I'm mildly interested in replacing the Nikki on my 12A with something more interesting, and I see a lot of Dellorto and weber 40s and 45s on eBay, but I have NO idea what would work well on the 12A. Any experience?

B

Kill No Cone 02-08-03 02:07 PM

Its a Dell!
 
I have a Dell on my 12A and it works great. I am in the process of putting together a street port 13B and I will use the Dell there too. I just found a Lakes sytle intake, which about 4" across and placees the carb just to the right of the engine. This intake flows a whole lot and should work well on the top end.

Good luck

RotorMotorDriver 02-08-03 03:04 PM

Im going to be getting a Weber DCOE as soon as I know where to pay ;).

~T.J.

mazdaspeedrex 02-08-03 04:54 PM

I've got a Mikuni on my 12A and I love it. So much better than the Nikki POS. The only problem is that You have to make sure you have enough fuel flowing to the carb especially at top end.

rxtasy3 02-08-03 06:49 PM

Seems like I'm the only one running a Holley. I had a Mikuni once and I didn't see any difference between it and the Holley at WOT. But since the primaries on the Holey r smaller than on those other 2bbl carbs, the Holley gets better gas mileage.


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