Looking for some parts

1980-1986 Datsun 720 forums. All 720-specific topics and discussion can be found here.
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luistone
Posts: 19
Joined: Fri Jun 08, 2012 8:44 am
Car: 1984 720 kingcab 4wd

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Hi I’m looking for a weber carb complete with adapter, filter, and also a header for a 1984 4WD with Z24 engine.
Thanks


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breadbox
Posts: 8549
Joined: Tue Oct 17, 2006 4:09 pm
Car: 89 Nissan 240SX
89 Koop
84 720 4x4KC
Location: Va Bch

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Ebay or any seller of weber carbs.

I am pretty sure I got mine off ebay, just make sure its the full carb kit like you described and not just the carb itself.

Davezilla
Posts: 95
Joined: Mon Dec 19, 2011 5:40 pm
Car: 1990 300ZX
1986 720 4x4

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Yup... ebay is a good place to get the stuff you need or you can go to webercarbsdirect.com or redlineweber.com.
I got my carb off ebay and got the rest of the parts as well as the right jets for it from webercarbsdirect.com. And on another side note, the Holley 5200 series carbs are the exact same as the Weber DFAV series carbs and all the internals are interchangeable with the Holley 5200 series and the Weber DGEV and DFAV carbs, but the Holley 5200 series and the Weber DF series are mirror images of the DG series meaning that the secondary is on the opposite side as well as the choke thermostat and the throttle rotates in the opposite direction.
The benefit of the Holley 5200 series carbs is that they were very common on American 4 bangers back in the early 70's to the mid 80's or so which means they are abundant and inexpensive where a Weber DG will cost about $275 or so, a Holley 5200 will cost under $100 in most cases for a remanufactured one.
Here's a pic of my truck with the Holley version of this carb installed and a total investment of about $90 after buying the carb, the adapter plate, and all the right jets... It's kinda hard to see but you can see that the choke is facing the valve cover instead of away from it in the pic. This carb was originally built for the '72 Ford Pinto, and the newer versions may have electronic metering rods so if buying the Holley version, avoid buying anything from the late 70's or early 80's.
Image

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luistone
Posts: 19
Joined: Fri Jun 08, 2012 8:44 am
Car: 1984 720 kingcab 4wd

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Hello

Thanks for the information; I'm on a budget so I was hoping to find something used in good condition but maybe a holley carb it's also a good choice. I was one a hurry to find a carb since it’s getting colder and my choke wasn't working but yesterday I got it running so maybe I will save a little and buy a new weber or a holley. I hope the fix will get me trough this winter, I don't want to spend money on re build kit since is missing some parts like fast idle cam.

Yesterday I took apart the power steering pump and Steering Gear and took it to a rebuild shop since Sunday pump stopped working.
Again thanks for the information

Davezilla
Posts: 95
Joined: Mon Dec 19, 2011 5:40 pm
Car: 1990 300ZX
1986 720 4x4

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For the Holley that's the exact same as the Weber you'd want to look up the 5200 series, but these were not all created equal since some of them will have the smaller 23mm venturi on the primary side. On the side of the Weber and the Holley's main body you'll see some numbers cast in the side of each barrel. The numbers you'll want to see are 26 on the primary and 27 on the secondary, this is the venturi sizze in milimeters. The best match to the Weber that's commonly sold for these trucks comes off a '72 Ford Pinto, it'll have the water activated choke where you can either run your heater hoses thru, or you can swap this out for an electric choke which I opted to do.
There's also the issue about the linkage and the throttle shaft rotates opposite to the Weber, I fixed this problem by making a taller throttle cable bracket, and took off the throttle cable horn off the original Hitachi carb and installed it on the Holley, problem solved there.. Then I needed to make a return spring bracket that mounts to the carb base bolt. These were the only issues I had to overcome to make this carb fit and work on my truck.

The other Holley choice would be the high performance carbs like the 350 cfm 2 barrel, it works great on these trucks and will perform as good as if not better than the 38/38 Weber plus you can buy all the jets etc locally if you need to tune it since these parts are common in almost every auto parts store, and you have a huge choice for air filters as well.
The drawback for this one is that you'll need to get the bigger adapter plate since this one's base is considerably bigger than the Weber/Holley 5200 base size, and you may need to buy a universal fit throttle cable as well as making a few brackets etc, not that hard to do tho...
For the 500 cfm Holley 2 barrel, this is too much carb for these engines which will make it difficult to tune if even possible, the problem is that the venturis are too big so they get a weak booster signal meaning you'll need to use larger jets but what works at cruising won't work under full throttle and vise versa... just stick with the 350 2 barrel if going this route.

Yes, you can put a 4 barrel on these too, the Holley 390 cfm vacuum secondary is right at home on these engines, but again, it'll have to go thru an adapter plate and some manifold porting may be necessary. From the people who I talked to who used this carb, they love it but some of them wished they would have used the 350 2 barrel since it's the easiest to tune and so trouble free. The benefits of the 390 4 barrel is that it has very small venturis so the boster signal is nice and strong at all rpm's, and it'll run off the primaries most the time saving you gas, but the power is definitely there when you step into it.

For me, I've gathered up all the parts to put a Holley 350 on mine and as soon as I got a free weekend I'll do the swap, I'm going to use a universal throttle cable and some pre fab brackets for the throttle and return spring to speed up the installation... When I do this I'll take lots of pics and do a write up as well as a full report on tuning and performance.

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luistone
Posts: 19
Joined: Fri Jun 08, 2012 8:44 am
Car: 1984 720 kingcab 4wd

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That’s pretty god information on the Holley carbs tank you! And now that you mention it the Holley 350 cfm 2 barrel looks nice and as you mention parts are widely available including air filters; is a little bit more pricey but maybe is worth paying a bit more. You will leave the manual choke or buy the electric choke kit? About the adapter plate were you found it? Will be expecting the post about the swap!


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