Projects Had anyone converted a vacuum carb to double pumper?

I would really like to see if anyone has attempted this even if you failed or got it to slightly work. Only one guy on the net actually admitted to doin it and getting it kind of working. I know it can be done. I hate naysayers.
I have a picture of the forum of the guy admitting to doing it.

 

There is no provision for the squirter on a vacuum secondary carb, if you want a double pumper then buy a double pumper.

 

That guy in my pic said he drilled and tapped and used a bowl and metering block off a double pumper. He said he did it but it didn't work right. I want to see if anyone has pictures of their own attempts or maybe what they did in detail.

 

You can get a decent double pumper on Craigslist, eBay or a swap meet for under $50.00 plus the cost of a decent rebuild kit
why bother with anything else?

 

Sounds like a snow job to me if he went to all the trouble to do it. He would remember exactly how he did it . There are plenty of good cores on ebay to rebuild if you need a double pumper.
My 69 396-375 4 speed Camaro ran 10's with the original vacuum secondary carb in super stock years ago.
The motor was legal super stock and so was the carb , but it was still a vacuum secondary Holley.

 

50 bucks yeah right try at least 150 for a stupid spreadbore double pumper super trashed carb on eBay. If anyone wants to sell me one for 50 bucks I'll buy it right now.

 

I've got 4 or 5 in this mess somewhere, that will be $50+ $100 shipping.......................................................

 

There USED to be a double (4 holes) squirter that went from the primary side, thru the choke wall with long tubes, and into the secondary side.
My dad had one back in the late 60's. He didn't have the money to buy a real double pumper.
After many hours of trying to get the engine to run better, the car ran better/quicker without it..! Got better milage in the stock form too as I recall.

Save your money and buy a carburetor that was designed from the "beginning", as a double pumper. There are things that can be modified, even carburetors, but me, in this case...I'd say buy a real double pumper.

Mike

 

What's wrong with a vacuum secondary set-up. All my carburated records at Bonneville and El Mirage were set with them.. Carbs/engines are a lot smarter than me.

 

In the 70's I converted a carb on a 60's big block in a friends Vette to a double pumper. There was a kit with the squirters and a gear drive for the secondaries. It's hard to remember stuff from the 70's if you know what I mean.

 

no problems more for me to find...

 

Here you go Mike.... You also need the "gear drive" throttle shafts to make it all work....

 

There is a cast boss the squirter sits on, the hole is specially machined with 2 channels for the fuel and at the bottom is a pressed in seat for the antisiphon slug. Drilling and tapping won't get the job done.

 

Trying to covert to a DP IMHO is a waste of time and effort for something that will be a screwed up mess as the end result.

 

Here's those cast in bosses for the squirters....
And both of these carbs are vacuum secondary versions...

 

And you need a double pumper because....... why ?

 

Wtf so it is true?

 

To get full power at take off because I'm a redneck duh

 

what a dumbass

 

Is this kit still available or is it all but legend now

where do you get that kit ? Or what do you type in on google to find it ?

 

I thought I was the only one with a collection of 4 bbls.
Bob

 

It shouldn't cost 100$ to ship unless you're in China lmao

 

I've shipped an 80lb receiver to Texas from the east coast for 60$ with insurance....

 

Why?????? Total waste of time. Will cost more to convert it than buy and rebuild one correctly.

 

This is the thing... we have like so many Holley gaskets and rebuild parts sitting around like boxes and storages of them. Cost isn't a factor at this point, and we have time to blow because we take things slow. If we get all our parts for free than how is it more expensive? We like to learn and modify and educate ourselves. This traces back to the early hotrodding days when there wasn't an Internet of people to say no you can't do this. I know it might not be feasible to actually convert a single pump to a double pump but I would like to see people's attempts at trying it anyway and what their results were! Willl I do it? I already have started with an 1850 Holley. Why? Because I have a lot of them for some reason and I'm snowed in and bored as hell and my internet isn't working good enough for Netflix ATM...

 

On the subject of customization btw... my cousin actuallly put a supercharger on a stock IH 345 with custom plates and everything and we really don't have any money

 

Nope! I got a shit load also.... Including a very rare list-4223 850 center squirter Holley... And an LS-6 carb....

 

Eelco was the company that made the tubed squirter and gear drive linkage kits....long since obsolete and no longer even in business....they do pop up every once in a great while on Ebay.

As far as doing the deed with conventional parts, all you need to do is copy what Holley already did. Tap the boss for screw threads, drill it for fuel feed and connected to the hole from the metering block gasket face. Press a tapered seat insert into the vertical passage for the needle or check ball and weight to sit on....you can even drill it careful enough to make the check seat in the vertical passage of the main body without having to press in an insert. DP baseplate linkage & shaft(needed for pump cam mount provision), pump stud and arm, a metering block, and a rear DP bowl....if you try to use a front bowl the fuel inlet is on the wrong side. High Speed air bleeds in the air horn top need to be resized.

If you know how to set-up a vacuum secondary right, you don't need this hassle and will be unable to tell the difference anyway....that's why there are vacuum secondary spring rate assortment kits and screw adjustable orifice vacuum pods available.

 

Acquire a book similar to this and learn to tune the carb you have before you ruin a bunch of parts. It would also be a good idea to learn the optimum style/type/ size of carb for your application. Also learn why that carb is optimum for you.

 

So it looks like it's up to the original poster to modify the vacuum secondary carb into a double pumper.
Let us know how it turns out.

I recall reading in one of the Holley books about this, it pretty much said what everyone else in this thread said.