Advice guys, is this carb any good to improve my 318?

[K9COP]

http://cgi.ebay.com/ebaymotors/Holley-carburetor-1968-Dodge-Plymouth-Cuda-Charger-69_W0QQcmdZViewItemQQcategoryZ34198QQitemZ130089220923QQrdZ1

Holley 600 CFM carb List # 3918    255 7

[mikepmcs]

Maybe a little big for the 318 but will most definitely work once you tune it up.  You might experience a little low end bog but will mostly likely be happy with it overall.  But if you can get it for that price I'd be buying it as well.

Heck i've got a Holley 750 Hp on my 383 and some say that's too much, but it flew right out of the box.

You posted in the other thread that your engine is stock correct and you are looking to make some easy power mods right?

I say get that bad boy!

v/r
Mike

[K9COP]

Thanks, I'll have a go and let you know. Will I need a new intake, or just an 'adaptor' to fit this carb.. there seems to be so many permutations..

[mikepmcs]

You have a 2bbl( barrel) carb now right, if so you will need a 4 bbl intake. I won't pretend to know too much about manifolds but it seems the edelbrock performance series would be right in line and not too costly for what you are doing.  Heck you could even search the resources available at your local salvage yard if you have one there and try to find a stock small block mopar 4 bbl manifold.  Aluminum will give you weight reduction though over stock manifolds.

I wouldn't put an adapter from 2 to 4 bbl carb on a manifold if there is such a thing


Keep the questions coming.   Ron, Chryco, Chall 340 and some others will jump in here soon enough and help you out.

v/r
Mike

[K9COP]

Thank you. My background is Skylines with stand alone laptop programmable ECU's, so it's nice to do some proper tuning! Look forward to more info. I need to pull my carb etc to see exactly how it all works..

[mikepmcs]

When you decide on a manifold it's good to match the bore with the carb(ie: spread bore or square bore)  I'll find some pics of what i'm talking a bout.  I'm pretty sure the one you are tracking on ebay is a square bore carb.

They do make an adapter from spread bore to square bore but if you can get the right stuff first time out you are ahead of the game.

2 quick pictures to differentiate between spread and square bore for you.

[Bones68charger]

I put a Holley 600 cfm on my 318 with this Mopar Performance dual plane intake 312-P4876335 it works good, but like he said on your stock 318 it bogs a little, I did not worry too much though because if you plan on souping up your car it will work fine. I probably need to put different jets in mine, but I am going to wait till I get my engine done this June to really worry about that.

[K9COP]

Thanks guys. Learning learning.. why does it bog?

[mikepmcs]

one more thing to throw at you is in regards to the throttle linkage(transmission kickdown) The 2 and 4 bbl linkages are differrent.  You will have to either extend your existing linkage to accomodate the 4bbl application or find the correct 4bbl linkage.  This is very important due to the pressure your transmission needs to realize, to operate efficiently/correctly.  If this isn't adjusted properly you stand a pretty good chance of ruining your tranny.  It is not hard to extend the 2 bbl linkage to work. I did it with a threaded barrel nut and some threaded rod.  Maybe i'll take a picture for you today of my backyard joe set up.

v/r
Mike

[Bones68charger]

Too much fuel..when I fist got mine installed it would flood and die when I put a foot into it, I believe all you would have to do is rejet the carb. I knew I was going to be doing more to my car, and it was almost winter anyway so I just put my car away for winter and I am going to tune it when I have the engine rebuilt in june.

[Bones68charger]

one more thing to throw at you is in regards to the throttle linkage(transmission kickdown) The 2 and 4 bbl linkages are differrent.  You will have to either extend your existing linkage to accomodate the 4bbl application or find the correct 4bbl linkage.  This is very important due to the pressure your transmission needs to realize, to operate efficiently/correctly.  If this isn't adjusted properly you stand a pretty good chance of ruining your tranny.  It is not hard to extend the 2 bbl linkage to work. I did it with a threaded barrel nut and some threaded rod.  Maybe i'll take a picture for you today of my backyard joe set up.

v/r
Mike

Mine seemed to work, maybe I should have someone else look at it and get a second opinion.

[mikepmcs]

You had an original 2 b linkage and it hooked up and adjusted properly to your 4b setup? cool.    My car would not provide the throw needed to make the tranny downshift when I put my foot in it.  So I received a lot of sound advice from people on this site and finally figured out that it just would not adjust properly due to the linkage differences.  I extended it adjusted it and now it operates properly.

check this thread out(my linkage doesn't look like that now, those pics were before i did the new backyard rig )

http://www.dodgecharger.com/forum/index.php/topic,9634.0.html

[Bones68charger]

You had an original 2 b linkage and it hooked up and adjusted properly to your 4b setup? cool.    My car would not provide the throw needed to make the tranny downshift when I put my foot in it.  So I received a lot of sound advice from people on this site and finally figured out that it just would not adjust properly due to the linkage differences.  I extended it adjusted it and now it operates properly.

check this thread out(my linkage doesn't look like that now, those pics were before i did the new backyard rig )

http://www.dodgecharger.com/forum/index.php/topic,9634.0.html

You got me kind of worried about it now, I had two other people look at it for me, and they did seem to worry.....I used a Holley carb not a Eddy like you..I wonder if that made any kind of difference?  The first thing I do this spring when I get the Charger out is ask another Mechanic to look at it again just to make sure...

I am sure I can buy another kick down linkage.. if need be.

[mikepmcs]

I now have a holley 750 HP and the eddy is gone.  It didn't work with either carb until I finally got educated here and found that was the issue.  One question is your car downshifting when you romp on it???


v/r
Mike

[Bones68charger]

To be honest I don't remember.. I put it on last summer right before I had to go back to teaching and I might have put 50 miles on it since the 4 barrel was installed. Everything seemed to work ok..... Except a tiny peice of metal got stuck in the carb and shot gas all over my manifold. I got that fixed adjusted the floats and went at it. The car would die on me when I would accelerate too much or if it did not do that it would spuder and then take off. I assumed it just needed smaller jets...


What did you put your 4bbl on 318 or 383?

[mikepmcs]

i have a 383.
original 2bbl car
M

[Bones68charger]

I put it on a 318...maybe Chryco or someone else could give their opinion on it.

[K9COP]

I'm listening along here and bid on the carb..

[mikepmcs]

here's my pics of my throttle linkage after I made the extension for it to adjust and work properly.

v/r
Mike

[K9COP]

Nice job, thanks. I got the carb for ten bucks!

[mikepmcs]

That's friggin awesome! Congrats. 


You'll be wanting a dual plane manifold for your application.  Better low end power over single.  Single plane  is more suited for top end performance.

Dual plane feeds both sides of the motor from 2 plenums vice the single that has a common plenum that feeds the gas to the intake runners.

You want that good throttle response and mid range power so dual plane is the way to go.

v/r
Mike