carb for slant 6

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Slant6Gilman

Slant6Gilman

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i just got a 600 cfm holley that was barely used and i got it for 150$. i want to build my slant but i am wondering how much i need to build it to use that
 
you gota Volare as well..... I need to get back on mine. been sitting dormant way too long.
you dont build an engine around a carb, that is totally backwards.
 
A 600 cfm carb is too much for a street driver slant, if it is a double pumper, you will be very unhappy. If it is a VS you might barely get away with it, but I wouldn't bet the farm.
 
volaredon said:
you gota Volare as well..... I need to get back on mine. been sitting dormant way too long.
you dont build an engine around a carb, that is totally backwards.
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Yes I know but I pretty much stole the thing and I'm just kinda wondering what people have done to run that size of carb
 
Slant6Gilman said:
Yes I know but I pretty much stole the thing and I'm just kinda wondering what people have done to run that size of carb
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It all really depends upon
1) your total budget, for the engine, transmission, rear end, auxiliary systems like brakes, cooling to name a few.
2) your plans - goals for the car, is a daily driver, a full time race car, drags or auto cross?
Figure out what you want to do with the car then see if that carb fits in. If it does not, move it on to someone that can use it.
 
Charrlie_S said:
A 600 cfm carb is too much for a street driver slant, if it is a double pumper, you will be very unhappy. If it is a VS you might barely get away with it, but I wouldn't bet the farm.
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my68barracuda said:
It all really depends upon
1) your total budget, for the engine, transmission, rear end, auxiliary systems like brakes, cooling to name a few.
2) your plans - goals for the car, is a daily driver, a full time race car, drags or auto cross?
Figure out what you want to do with the car then see if that carb fits in. If it does not, move it on to someone that can use it.
Click to expand...
10-4 thank you buddy
 
volaredon said:
you gota Volare as well..... I need to get back on mine. been sitting dormant way too long.
you dont build an engine around a carb, that is totally backwards.
Click to expand...
I once bought a hat that was too small, so I went to a surgeon and had him reduce the size of my head. :eek:
 
A buddy has a 500 cfm Carter on his 318 and is quite fast.

The rule with carbs is run smaller, not larger. That same buddy installed a thermoquad on a slant. It ran ok but not well enough to warrant staying on there. And a thermoquad has itty bitty primaries. Way smaller than most holley's.
 
Slant6Gilman said:
i just got a 600 cfm holley that was barely used and i got it for 150$. i want to build my slant but i am wondering how much i need to build it to use that
Click to expand...

Not much. It'll take a 600 ok. You'll need to upgrade the exhaust "somehow". Either add headers or bore out the exhaust manifold like I had my friend Freddie do for me. You can read about it here:

Exhaust Manifold Mod

It's not hard to do, but I chose to let Freddie do it because my skills with a hand held grinder suck. I never would have thought there would have been that much meat in the outlet of a slant exhaust manifold but there is.

Also, a nice high flow air cleaner won't hurt. While internal engine mods are not necessary, it won't hurt to have the head milled, re-cam it if you want to go that far. It just depends on how far you want to go. As long as you use a vacuum secondary 600, it'll be fine as you can adjust the secondaries with the diaphragm springs.
 
To Run that 600 CFM, Cam swap 264-268 Duration, Head Porting/ Milling 9-9:5 CR, Headers 3.23-3.55 gears. On a stock slant six Two Barrel Carter BBD is the ticket, I have found that a four barrel on a stock slant will run slower than a two barrel. Once you your increase Compression the four barrel really shines through. Good luck!
 
Slantsix64 said:
To Run that 600 CFM, Cam swap 264-268 Duration, Head Porting/ Milling 9-9:5 CR, Headers 3.23-3.55 gears. On a stock slant six Two Barrel Carter BBD is the ticket, I have found that a four barrel on a stock slant will run slower than a two barrel. Once you your increase Compression the four barrel really shines through. Good luck!
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The BBD is only about 193 CFM. That's about HALF what a Jeep 238 can handle according to the Jeep guys and probably close to the same for the 225. The 600 can be tuned to run on a stock slant just fine as long as you upgrade the exhaust. It flows less than 300 CFM on the primary side. As long as it's tuned so the secondaries don't open too early and with the right power valve and jets, it will run good. I've done it before. Will likely do it again, although with something like the Street Demon.
 
Autolite 2100 with 1.08 on the float bowl. Use the AMC version as it has the proper ported vacuum fitting and a lever for kickdown linkage. Rebuild to '73 Jeep 304 specs. Use #46 jets. This gave me 24mpg in a '73 Duster with 2.73 gears and my wife 1st place in her bracket at the race track.

You can buy conversion kits off eBay for Jeeps with the 258.
 
Slantsix64 said:
To Run that 600 CFM, Cam swap 264-268 Duration, Head Porting/ Milling 9-9:5 CR, Headers 3.23-3.55 gears. On a stock slant six Two Barrel Carter BBD is the ticket, I have found that a four barrel on a stock slant will run slower than a two barrel. Once you your increase Compression the four barrel really shines through. Good luck!
Click to expand...
thats what i was planning to do. im going to do cam, headers, intake, shave the head, and maybe bore it out a little.
 
RustyRatRod said:
Not much. It'll take a 600 ok. You'll need to upgrade the exhaust "somehow". Either add headers or bore out the exhaust manifold like I had my friend Freddie do for me. You can read about it here:

Exhaust Manifold Mod

It's not hard to do, but I chose to let Freddie do it because my skills with a hand held grinder suck. I never would have thought there would have been that much meat in the outlet of a slant exhaust manifold but there is.

Also, a nice high flow air cleaner won't hurt. While internal engine mods are not necessary, it won't hurt to have the head milled, re-cam it if you want to go that far. It just depends on how far you want to go. As long as you use a vacuum secondary 600, it'll be fine as you can adjust the secondaries with the diaphragm springs.
Click to expand...
would a dremel work or is that what he used? or would it be better just to find some headers?
 
Slant6Gilman said:
thats what i was planning to do. im going to do cam, headers, intake, shave the head, and maybe bore it out a little.
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Yup, headers,cam,comp,intake,carb will wake that slant up, also dont forget to recurve the distributor as well.
 
I had always heard that a BBD was more like 280ish cfm. Your saying that it is only 193 seems quite low
 
Slant6Gilman said:
would a dremel work or is that what he used? or would it be better just to find some headers?
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Depends on how long you want to be holding that dremel. Sure it will work but it would be like cutting 10 acres with a manual reel push mower. Kinda the opposite of the 600 cfm on a slant 6 overkill.
I used an air powered die grinder and switched between bits a few times. I bolted a flange gasket to the manifold's outlet flange so I knew just how much I had to grind out of there. As it turns out the outlet hole as cast was off center from how the gasket bolted up, meaning that the head pipe would have also been. I only had to grind about 3/4 of the way around the outlet hole. I centered that up as I opened the manifold outlet up. I have done 2 of them so far and bought were about the same diameter and one was slightly more off center to begin with than the other one was. But both were somewhat off center to start with
 
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Slant6Gilman said:
would a dremel work or is that what he used? or would it be better just to find some headers?
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Freddie had two hours in the one I linked to. Headers are what? over 400? It's a decision you're gonna have to make.
 
Slant6Gilman said:
But

But would headers work better then stock cut out a little
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Hell yes headers will always be better. I went from stock manifold then a stock manifold ported it out to 2.25 felt a little bump. Then custom duals made from the stock manifold made bigger difference over the stock manifolds i would say 10 H.P then i went straight headers and god damn pulling in the 3500-5500 range was way better. But i would say there is the cons of headers leaks of course but i use remflex gaskets havent had any problems. My Dart is a daily driver so i added water cooled plate under the intake. With the duals i had more room in the engine bay to adjust my gear box and clutch rod, headers made it more of a ***** cause of the smaller engine bay in the early abodies. Check on ebay i seen some slant six headers selling for 250.00-300.00 range.
 
There's also the cons of price, headers ain't cheap and they will eventually rust. So, if you plan on keeping your car a long time, there's "THAT".
 
RustyRatRod said:
If you're talkin to me, of course I have a welder.....and the know how to build headers. I don't want headers. I want a manifold.
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no, i was talking to Gil
i figured you wouldnt need encouragement to build a set of headers
 
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