dual carbs

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datmo
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dual carbs

#1

Post by datmo »

So as many of you know. I want dual carbs and decided to go with some dual su's thanks to flatcat.

I was wondering what i exactly need.
I obviously need the carbs, linkage, and throttle.

I read that I also need a different mani?

and do you think this could be done if I've never done much engine work?
Just a kid with a love for datsuns and no money.
4 doors riding slow and hangin loose.
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Re: dual carbs

#2

Post by flatcat19 »

If given all the pieces, yes. Nothing too it.
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Re: dual carbs

#3

Post by wayno »

You need a serviceable set of dual SUs complete, it would be best if you took them off a running engine that runs properly.
Lots of people are selling dual SU setups that are sitting on a shelf, they are on that shelf for a reason, the ebay set that you looked at are likely a good set, as they were pulled off the engine because he converted over to R1 motorcycle carbs.
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datmo
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Re: dual carbs

#4

Post by datmo »

flatcat19 wrote:If given all the pieces, yes. Nothing too it.
I looked at it today and it just looked like a few bolts that connected the mani to the block and then the ones that connected to the carbs.
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datmo
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Re: dual carbs

#5

Post by datmo »

wayno wrote:You need a serviceable set of dual SUs complete, it would be best if you took them off a running engine that runs properly.
Lots of people are selling dual SU setups that are sitting on a shelf, they are on that shelf for a reason, the ebay set that you looked at are likely a good set, as they were pulled off the engine because he converted over to R1 motorcycle carbs.
Thanks.
I also think that's very important.
I'll def ask around before I buy the set I do.

also, if they sell the carbs, are the mani's hard to find?

I was talking to my dad about my ideas and he said I need a complete new exhaust system or something?
I didn't know that nor believed it much?
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Re: dual carbs

#6

Post by RedBanner »

If you have conjoined manis now. Then there is more to the swap.
wayno » Sat Jul 12, 2014 9:40 pm wrote: Everything is either tight or actually rubbing.
Taterhead » Tue Aug 05, 2014 2:29 pm wrote:Datsun gods will give you one working gauge, gasoline or speedometer; you can't have both.
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Re: dual carbs

#7

Post by wayno »

I have never actually tried putting a dual SU manifold onto an engine with a stock manifold, but that is what I believe that datsun/nissan did, as I have never seen a stock datsun/nissan header for a L16/18/20b, as I believe they use the stock exhaust manifold for everything, including there dual SU packages.
Fact is, the stock L16 exhaust manifold is basically a header, as for the exhaust system itself, if your going to hot rod it, you will likely need something a little bigger than the L16 exhaust system from the exhaust manifold back, but that is my opinion.
If you want to figure out how hard it is to find a L block dual SU manifold, try to find one.
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Re: dual carbs

#8

Post by datmo »

RedBanner wrote:If you have conjoined manis now. Then there is more to the swap.
I'll take pics of my engine tomorrow maybe when I have time.
I'm a little loss to be honest.
wayno wrote:I have never actually tried putting a dual SU manifold onto an engine with a stock manifold, but that is what I believe that datsun/nissan did, as I have never seen a stock datsun/nissan header for a L16/18/20b, as I believe they use the stock exhaust manifold for everything, including there dual SU packages.
Fact is, the stock L16 exhaust manifold is basically a header, as for the exhaust system itself, if your going to hot rod it, you will likely need something a little bigger than the L16 exhaust system from the exhaust manifold back, but that is my opinion.
If you want to figure out how hard it is to find a L block dual SU manifold, try to find one.
So the exhaust system should be fine.
I'll just need to change the mani in order to fit both carbs onto it.
But the way you make it sounds, I'll never find one? lol

and no, I'm def not going to hot rod it. I don't want it to be that loud or anything of the sort.
It'll just get annoying eventually, especially for a daily.
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Re: dual carbs

#9

Post by flatcat19 »

There are basically 3 different kinds of SUs.
Be careful as to what you'll be buying.
1. L series 38mm 2. Roadster carbs 3. 46mm Z car carbs.

Each type has variants. Do your research.
Also know what your future plans are when getting ready to buy.
Buying 46mm Z carbs is pointless if planning to stay L16.

I wouldn't stress the exhaust too much.

Also-you'll be better off buying a full set(mani, carbs, linkage) from the get go.
A complete set has a better chance of being a running set from the start.
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Re: dual carbs

#10

Post by datmo »

Why is pointless to buy 46mm?

I'll be looking for a full set then. I'll be patient about it.
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Re: dual carbs

#11

Post by Laecaon »

46mm is pointless pretty much ever, too big. the LZ23 might be the exception, but even Ztherapy and Troy Ermish says to run 38mm.

I have the 38mms on my L19, and they are so much better than my 32/36 ever was.
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Re: dual carbs

#12

Post by wayno »

Did the ones on Ebay sell?
That guy is local to me, and I am fairly sure they are a good set with everything.
I have bought from him a few times lately, but I don't have his number at the moment.
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Re: dual carbs

#13

Post by flatcat19 »

I had 40mm Roadsters on the LZ23 521.
It felt like it was running rich big time.

Unless you're packing one hell of a motor with big valves/cam and exhaust 46s are too much.
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Re: dual carbs

#14

Post by flatcat19 »

wayno wrote:Did the ones on Ebay sell?
That guy is local to me, and I am fairly sure they are a good set with everything.
I have bought from him a few times lately, but I don't have his number at the moment.
I don't see them.
Datmo should have pulled the trigger on that shit!
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Re: dual carbs

#15

Post by jayden71 »

I like this thread!

Good carb info!!

:thumbs: :thumbs:
DRIVEN » Tue Nov 04, 2014 6:30 pm wrote:I think Bill might be gettin laid.
Ni10 » Wed Nov 19, 2014 7:56 am wrote: all Datsuns ran when parked.
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datmo
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Re: dual carbs

#16

Post by datmo »

flatcat19 wrote:
wayno wrote:Did the ones on Ebay sell?
That guy is local to me, and I am fairly sure they are a good set with everything.
I have bought from him a few times lately, but I don't have his number at the moment.
i got out bid and didnt have enough money in my account.

I don't see them.
Datmo should have pulled the trigger on that shit!
Just a kid with a love for datsuns and no money.
4 doors riding slow and hangin loose.
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datmo
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Re: dual carbs

#17

Post by datmo »

So I've come to this set of dual su's that I'm really digging and got a pretty good price on them

Image
Image
Image

One question, do you need a choker cable to start them or no?
I don't have a choker cable and have seen the prices :(
Just a kid with a love for datsuns and no money.
4 doors riding slow and hangin loose.
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Re: dual carbs

#18

Post by datmo »

So i bought the carbs and say some fuckin awesome air filters. Do you guys know where i can buy em? I like the ones that are hexagon covered kinda thing? Ill get the pic from my build thread and post when i get home.
Just a kid with a love for datsuns and no money.
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Re: dual carbs

#19

Post by Taterhead »

Gotcha covered. These are the ones I have. They came on the carbs and I don't know the name of them but I took some pics for you.

Image
Image
The backplate
Image
The filter assembly taken apart
Image
Image

There is no info what-so-ever on the backplates. The wire retainer just snaps over the filter over the back edge of the backplate. Hopefully this helps a little
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datmo
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Re: dual carbs

#20

Post by datmo »

Yep! those are them! I just need to know the name or some sort.
They''re beyond freaking awesome man!
Just a kid with a love for datsuns and no money.
4 doors riding slow and hangin loose.
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