Holley Spreadbore 0-6213 for Boost?
 

Has anyone ever used the Holley Spreadbore 0-6213 800 cfm manual secondary carb for a turbocharged application?

We played around with some of the Spread Bore 800 carbs when I worked for Holley in the 70s using boost.

They worked ok when we put them in "a box" like the later 90s old Vortech Supercharger Units were, with some of Vortech's early boosted engine projects.
These were lower boost projects like 12 psi max.
You would have to buy the box and then machine it for the spread bore manifold inlet gasket pattern. I have a couple of the enclosures on the shelf. Better ways to do it with a Square Holley but the Modded spread box box will allow Holley or Q-Jet carbs to be used with moderate boost levels on the street.

Picture of a Vortech Enclosure and the parts attached. Jegs wants $1000 for the box. I would want less for mine, LOL!

Tom V.

Doing it this wayin a box , does it require all the same mods with the power vavle ? Or is there a different way?

Tom, I see a lot of people running just a carb hat on you tube. I was looking to run a modified air cleaner housing under my shaker scoop (76 T/A), without loosing the original stock look. Without putting the carb in a box what would be my biggest hurdle?

Thanks,
Vernon

1) Pay money for a C&S Holley Square Bore Carb $$$ and then the carb/engine will run right with boost.

2) People make shaker hood scoops work with Square Bore Holleys all the time. Not typically with Bonnets on them though.

3) Ken Crocie did a Blow-thru Q-Jet Bonnet/Shaker deal that took a bunch of effort (Dyno Time) to get right but you would need his other hardware. Very Rare.

No easy way to keep the Shaker on the engine without some effort and a bunch of fab work.

The Box would allow you to bolt the shaker on the Box and run low boost with the Shaker still shaking.

Tom V.

Forget it.... if you want to do a carburated/turbo deal Call Kevin @ CSU an have him hook you up with carb and bonnet..... It'll save a lot of time and hassle!

He's a forum member here and a great guy to deal with !

Are you doing this because you have the crarburetor and just want to make use of it or to do something different then everyone one else? Im sure you can make it happen if you want..

I don't even have the carb. I really would like to do a rear mount single turbo. Hiding the charge air pipe through the factory fresh air duct work. Even using the factory manifold. Other than using full length headers I want the engine compartment to appear stock. Factory A/C included. Not a race car by any means, just a different build. My way of thinking was the Holley would be easier to set up than my Quadrajet for forced induction. If I were going to replace the intake manifold I would probably lean toward the Holley Street Dominator single plane. Then I could use a square carb. I just really want to keep it stock appearing. I would like to see between six to seven hundred horsepower under full load and still have great drivability just cruising.

If you grind off the Holley Street Dominator logo on the intake 99% of the Chebby guys would never notice the difference. Charlie66 did a lot of his own square carb Holley calibration work himself. A very good boost tuner.

Tom V.

I have a spread bore holley. Ill have to look at it and see how( if any) different it is then the square bore in terms of how to make it boost ready. Ive never even really looked close at it.

Changing the manifold and painting it would be a good way to go like Tom said too..

I like your idea, i hope you go forward with it and share the build here so everyone can follow ...

Good luck ...

I would appreciate you looking at the spread bore for me Charlie. I'm not against sending one out to be converted if it will work, or setting it up myself.

Thanks for your information Tom and 69GTO. I very much plan on doing this, its just a matter of when. I will research until I know exactly what I need and then begin to collect the parts little by little. The current build is a 10:1 462 6X-4, 041 cam. I will most likely use this bottom end with a set of 111cc + heads.

Ok, i looked at the carburetor and it looks pretty much the same as the square bore but it still is going to be a learning curve . I havent seen it done with one before so you would be on your own if you had specific questions with pertaining spreadbore blowthrew mods. It would be easier to change to a square bore and change your intake, but cooler to actually succeed in having the first spread bore blowthrew.. So thats something you're going to have to think about . If it was me, being i love one off stuff that knowone else has, I would try the spread bore with the mind set that it might not work out to my liking ... But then again i believe if you really want to make something happen and are willing to take the extra steps needed , you will eventually get there...

Thanks for checking that out Charlie. I will check with Kevin from CSU and see if he has ever done a Holley spread bore 800 or has recommendations. I have a vision of what I want, and hopefully its not impossible.

Good luck....

Good Luck, Tom V.