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Single carb for performance upgrade - any recommendations?
Uber Kafer - July 16th, 2010 at 11:35 AM

Has anyone got any experience to share regarding any of the single carb performance upgrade kits for a type 1, that is currently on the market in Oz or the US.
I am keen to hear about quality, ease of tuning, driveability, size and availability of jets, for 1600 or 1800 twin ports. I need to replace a 34pict-3 and I would prefer to upgrade.
And lets not get bogged down with comments on whether or not I should change it, or whether I should go straight to dual carb setup...please.


EgeWorks - July 16th, 2010 at 02:14 PM

The single centremount IDF Weber ices up real bad in cool climates - not terribly fuel efficient either.

I know you said you don't want it, and opinions are like arseholes, but spending any money 'upgrading' to a non-standard single carb system is a waste in my experience.

Maybe if you are turbo/superchargng they have a place.

In saying that, I have a 44IDF Weber centremount kit in excellent condition for sale if you want to experiment.


Uber Kafer - July 16th, 2010 at 02:51 PM

thanks, but how cool is cool cool climate, do you mean around Melbourne or in the hills/mountains/snow?? I'm in the west on the coast..Mediterranean climate.


EgeWorks - July 16th, 2010 at 07:09 PM

It was pretty bad in Melbourne in the winter.


vlad01 - July 17th, 2010 at 09:20 AM

the stock manifold is more restrictive than the stock carb. I wouldn't bother either.


11CAB - July 17th, 2010 at 09:40 AM

I had a 40DCNF on a 1776 engine that ran well, I've since sold it to a mate who had it rejetted and fitted to a 1916. The throttle linkage pulled the wrong way though, so I modified it so the it went the other way so the mixture screws were easy to get to.


hulbyw - July 17th, 2010 at 11:41 AM

Hey 11CAB, don't suppose you remember the venturi size and jets you used on the 1776? I have a 40dcn destined for a 1776 when I can find time to build it.
Cheers


Uber Kafer - July 17th, 2010 at 08:14 PM

ok, refer back to my original question, and I would like to know about kits, (which includes new manifold to suit the carb), which are on the market now. As for the icing issues some kits have a fairly elaborate preheat system which integrates with the exhaust manifold runners. I am interested to hear about them.

As for the 40DCN I ran a 40DCNF but that was in 1980, so I dont know if thats relevant. Are they still available?.

So, does anyone have any good advice on complete single carb kits that are on the market right now?

thanks


barls - July 17th, 2010 at 08:52 PM

ive run the 32/36 dncf progressive on a bug and it went really well apart from fuel consumption.
i actually found the twin barrel progressive off a lada niva was a better version.


sander288 - July 18th, 2010 at 06:42 PM

what about a single Kadron kit, they are cheap, easy to tune and known around and basically a bigger version of the stock solex...


Uber Kafer - July 19th, 2010 at 08:58 PM

good point.

Anyone got any comments on the single Kadron Kit?


wiseoldub - July 19th, 2010 at 09:55 PM

i have a 40 dcn weber here on a manifold that willl fit straight to a single port motor if you want it. i have not run this one, but on a previous 1776, i ran the same one and it was great. fuel efficiency was governed by my right foot. drive conservatively and you won't use too much. heavy foot it and you will go faster, but use more juice. i will set it for $400 including the manifold. easy upgrade that will work on a 1500 and up to a 1776. other than that, a duel carb set up for kadrons on a single port motor is available and works well. my mate has just put a kit on his car! very good! i will be building a 1640 and using these! $650 was the cost of the last set! worth it!
see how you go
cheers, josh


matberry - July 19th, 2010 at 09:56 PM

A customer of mine is running the above mentioned 44 IDF single kit on a 1915 relatively std engine. Drivability is great, power ok, and no preheat and as far as I know, no icing issues. It's in a manx buggy with 4-1 exhaust, but lives in Qld. I'd recommend it with a good preheat system and/or a warm air intake for the air filter for use down south.


sander288 - July 20th, 2010 at 01:26 PM

reading into the single kad's and looking for them, I don't think EMPI sell them anymore...

sorry!

The other things that came out of what I was looking at was it is better to just re-jet and tweak a 34mm solex rather than go with the single Kad

Cheers

Shaun


ctefeh - July 20th, 2010 at 09:56 PM

Uber,
I wound up researching a lot because I intend to run my single 40 DRLA. 3 options that are relatively applicable.
1. Redline Weber/Aircooled.net
2. CB Performance low profile
3. Empi single (for IDF's/DRLA's)

The CB one requires fitting of a cable in an "up 'n' over" your shroud affair. Functional but fugly if you ask me but everyone is different.

I didn't bother with the EMPI as (N.B.!) they never show behind the manifold. One look and you'll see whether the pre-heat is good or not. I'm suspicious of the CB one.

That left option 1 which I bought. That being said I have a %$@#$&-load of work to do on it. Wish I'd taken it out of the box when I first got it:mad: . Anyway, it is fixable...
The preheat on this manifold runs all the way up the back so both barrels will get heat. I've mocked mine up thus far and it is somewhat of a skycraper but will fit behind the decklid.

I went with a DRLA due to easier tuning compared with an IDF.

None of this is up and running, but I am chatting to a bod in the US who runs a similar set-up (for a Semi-Auto too, just like me!) and he's pleased.

EMPI also for a while marketed a 40/44 (Kadron) single carb kit but there was minimal preheat, so I chucked that idea.

If you get a steel tube IR manifold, you can weld an enclosure type of affair out of thick steel sheet to funnel/trap preheat under the carb.

I'm in Canberra, so heat means a lot anyway but anecdotally singles can be a pig without it:lol:

One last tip, good thick alloy aircleaner base and top is desirable too.

2 Cents
Ctefeh


Uber Kafer - July 21st, 2010 at 02:13 PM

Good stuff, now we are getting some good info happening. I will check out the manifold you mentioned in option 1.

Apart from the manifold what is the advice on the carbs? I am aware that original Weber carbs are rare and expensive so what are the generic copies like for quality etc, ie: the ones made by EMPI etc.


ctefeh - July 21st, 2010 at 11:46 PM

Uber,
This one can be subjective at best. I went with a Dell as I figured it would only hurt me a little if I got taken. As luck would have it, the carb was in great shape and after buying a full rebuild kit from Alpha750s it came up like a new one.

So....IDF's.

Made in Italy = Good....but no longer made
Made in Spain = Good, and can still get them via Redline/Aircooled. Massive array of parts, interchange with
EMPI but MEASURE to be sure.

Made by Weber USA = suck big time, avoid at all costs.

Made by EMPI (HPMX) = 50/50 . Some have good experiences, others not so. Quality Control problems ranging from easy fix to garbage bin time. I started my search some 2-3 years ago during the EMPI clone debacle. For the IDA series they appear to have lifted their game.

I get the jitters sometimes thinking about stuff that is in stock in Aus, like how old? Was it made when "X" was bad etc? Has any retailer physically checked them? I just don't know who does and who doesn't.

A few things I've learned along the way. Clean, clean, check & adjust to spec - even brand spankers!!.

IDF's come with F11's (emulsion tubes) IIRC normally but F7's are required for a single. $$$'s extra already. If you buy from John @ aircooled you get tech support and can question his brains out.

On the downside with manifolds, I am not 100% sure you'll get one that is marketed for a 40 IDF. I have a sneaking suspicion you'll get a 44 one with a smaller carb. That means you have a mismatch between throttle plate size and the holes under it. Your manifold boots may not fit anymore. 15 bucks delivered on ebay for Silicone ricer stuff can fix that. Metal manifold to head gaskets. All the ranting on about heat comes down to trying to get proper atomization of fuel happening.

Don't get me started on jetting:lol: . Simply because I'm :crazy: I'm purchasing some brass rod. Have the lathe, the micro drills, the reamers so I can fab up some stuff. It may not be necessary at all but I can try!
At least with IDF's the F7's seem to be the best bet and Weber do have a lot of E-tubes. Dells do not.

Anyway, my fingers are worn and that must be 2 Bob worth. As with anything, that's only my take on it.


HTH
Ctefeh