Extractors/Weber Onto 4K

[sepblaster]

Hey All,

 

Need a bit of help/advice. I have searched to find out about this topic, as I do when any question arises. Usually I find the answers I'm looking for but not this time.

 

Recently got a 32/36 Weber off ebay, along with a redline adapter plate to reuse the stock inlet manifold. I've ordered some Genie extractors from my local mechanic and they'll be in later this week, so I'm wanting to fit it all up.

 

My question is about the 'hotbox'setup between the standard inlet and exhaust manifolds.

Is there actually airflow between the two? or are the just bolted to each other to create that warming effect that toyota thought would be great? Just wondering because when the extractors go on, I'm assuming the hole in inlet side of hotbox has to be covered and wondering how best to do?

 

I'm sure someone out there knows as a lot have extractors, so any help would be great. :hmm:

 

 

Cheers

 

joe

[Twinky]

The early model ones were just bolted together, but the exhaust manifold side had a large hole exposed to warm up the inlet.

The inlet itself is not opened up.

Since you are getting extractors it won't be a problem for you. Unless you have that shitty exhaust recurculation

crap them you will have to block that off, if not don't worry about it.

[altezzaclub]

Are you going to round off the edges where the air turns a right-angle inside the inlet manifold?? That always seems a major obstruction to me.

 

Check the fit between the extactors and the inlet and the head before you bolt them up, they usually don't fit very well & jam on some weld causing problems later on. A dummy head is really good for that if you haven't got the head off the car.

 

It will be interesting to see what jets you run in the Weber- I think most conversions don't work out very well as they don't get jetted properly.

[sepblaster]

Thanks for the advice guys, with a stock cam where do you think I should start with the jets, I've read that with the 32/36 it's generally a good idea to start with the 'standard' jets that come with it? I thought they would be supplied to suit the application when buying carb new, therefore be different for each application?

 

Being a secondhand carb, I am rebuilding it and will be probably buying new jets in the process i guess... (first carb rebuild since i was 15 and working on my motorbike, should be a quick learning curve :blinks: ) Can anyone lead me to a recommended starting point with jet sizes. ie- something that it will run ok then I can play around later.

 

 

In regards to the right angle on the intake, haven't had it apart yet so i'm not aware of it! Will have a look see when i've got it apart :hmm:

Cheers

 

Joe

[sepblaster]

Just for any other novices going through the same thing trying to nut out a 32/36 dgv... I found the following page after a bit more research, it has all the stock jet sizes right down the bottom of page. Another page suggested that it will run fine with the stock ones, but obviously i'll need to tune them to suit the specific application.

 

http://www.carburetion.com/diags/3236dgvdiaginfo.asp

 

cheers

 

Joe

[altezzaclub]

Useful stuff-

 

http://datsun1200.com/modules/mediawiki/index.php?title=Weber_32/36_Carburetor

 

Its actually a bit big for 1300cc 4Ks, it runs out to 2300cc.

 

Carburetor Adjustment

[edit]

Float setting notes

1. Fuel pressure is critical to float spillage. Redline recommends 2.5 to 3 lbs
2. For aggressive off-road float drop should be limited to 44 .5 mm max drop

Reference: http://www.redlineweber.com parts_breakdown

 

 

 

 

[edit]

Carburetor set-up and lean best idle adjustment

Baseline settings (to get your engine started)

 

• Speed Screw 1 to 1-1/2 turns
• Mixture Screw 2 turns

IMPORTANT: Adjust the float level before messing with the idle screws.

 

 

After you get the engine started and warmed up, adjust the idle mixture exactly as you would adjust the stock Datsun carburetor. The Weber DGV is adjusted the same way.

 

Idle Speed and Mixture Adjustment

 

NOTE: Idle speed must be adjusted with engine fully warmed, choke butterfly fully open. Take off air cleaner lid and confirm the choke is fully open before proceeding.

 

1. Adjust curb idle speed. Carburetor Specifications vary, but any stock Datsun engine should idle fine at 750 rpm
2. Mixture adjustment. Specs vary, but this will make any stock Datsun run nice:
   • Adjust idle to 800 rpm
   • turn mixture screw in (clockwise) to lean the mixture down to 750 rpm
   • Just learning? To get a 'feel' for this adjustment, turn the screw by half turns clockwise and anticlockwise till you hear the engine speed up and slow down. Then fine turn with 1/4 turns. Do this repeatedly until you are confident of the results

Fast Idle: this is part of the choke adjustment, and isn't done with the engine warm. See the Choke section.

 

Also see http://www.redlineweber.com/html/Tech/carburetor_set_up_and_lean_best_.htm

 

[edit]

Jetting (Tuning)

You will need a Performance Jetting Kit. It is a selection of jets to fine tune your power and fuel efficiency. You don't want to be one of the yahoos driving around belching black smoke all the while feeling proud that your car actually runs -- you can have power and economy both with a little bit of effort.

 

 

<a href="http://datsun1200.com/modules/myalbum/photo.php?lid=15576" class="external text" title="http://datsun1200.com/modules/myalbum/photo.php?lid=15576" rel="nofollow">

 

 

If you buy a kit for your specific engine, it will run fairly good out of the box, but should still be tuned to match your engine. If you obtain one second-hand, count on swapping jets, emulsions tube and other tuning parts to make your engine run right. Black smoke, smelly exhaust, jerky acceleration and poor fuel economy is what you get before you tune it. It may "feel powerful", but you can make it run even better with some patience and the right parts. You can get the tuning parts from Redline:

 

• Jets
• emulsion tubes
• throttle pump nozzles

For proper tuning, it is important to evaluate all of these:

 

Weber 32/36 jets

 

IMPORTANT: If you push down on this spring-loaded power valve actuator, then sucking on this hole should keep it pulled down. If instead, the hole leaks, you won't be able to tune the carburetor correctly. Replace the diaphragm.

 

Top-End Performance of Hollywood sells Redline Weber kits. Here is the jetting they list for the performance 32/36 kit for A-series engine. Presumbly this is for a stock engine:

 

Carb: 32/36 DGAV or 32/36 DGEV

Part #: 22680.033B

Venturis: 26/27 (compare to

Optimum Carburetor Choke Size

)

Auxiliary venturis: 3.5/3.5

Main jets: 140/140

Emulsion tubes: F50/F50

Air correction jets: 170/160

Idle jets: 60/50

Jump jet: 50

Needle valve: 2.00

 

anb008 had his standard A12 with Weber 32/36 carb rejetted and dyno'ed. The jet settings are:

 

Primary mentioned first, then Sec...

Air Correction: 175/145

Fuel: 120/145

Emulsion Tube: F66/F66

Choke Tube: 3.5/4.5

 

 

Idle:

50/55

[parrot]

If you are doing this, why not get the cam and head done too.

 

That is where you will really see the benefit of adding the carb and exhaust.

 

Realistically shouldn't be too expensive. Keep to a moderate grind on the cam and it will transform the car.

[sepblaster]

Thanks for the info guys.

 

Keith, that is the sort of article i've been trawling the net for. Thanks.

 

Parrot, I am going to keep the engine together for as long as it goes! But as soon as it needs to be taken apart i'll be getting the cam done and get everything in there neatened up. After that I don't want to do much else to the engine, as it's good being in the 1300 class at the car club, not many competitors in the class for one, but the most important bit is when you beat someone in a bigger class there's more bragging rights :dance:

 

suspension will be slowly (and cheaply) worked on after that....