69 Cuda single or dual intake?

[6packdart]

Ok ,please forgive a mistake or two , this is new to me and the guy's around here just smile and say I wouldn't understand it anyway,so here is what I would like advice on . I have a 69 Barracuda Fastback that is running a mod. 318 that has a edelbrock streetmaster single plane aluminum intake on it , should I keep this intake or would a dual plane work better on this motor? Here is the information that I do know about my motor:doner block is a 1979 casting that was bored .040 the 360 heads were done .020 , main .010 , con. rod .010 ,double rolling timing chain & gears , 360 valves, the cam has a lift of .286 on int. with .296 on exh. valve lift is .429 on int. .444 on exh. lobe ctrs. is 112 on int. 116 on exh. I'm running a 625 carter (which needs replacing ), 360 exhaust manifolds with 2 1/2 " pipes and just enough muffler to make her legal (which isn't much ! ) springs and lifters I'm not sure about ,compression ratio is roughly 9 to 1 ( ? ) , a 2500 stall torque , 727 tranny (console shift ) 8 3/4" sure-grip with 323 gears . Oh ! and it has a single point distributor. This motor is working fine at present after a few adjustments were made , so should I keep the single plane or be a good wife and do the swap hubby wants to the cast dual plane ?

[jasontlit]

I vote for a dual plane...considering your t-converter and your gearing. The engine mods. don't really point to a single plane set up either. Also, assuming this is a street driven/general purpose ride.

I also vote for the intake I'm using which you can find in my signature, but you'll need a carb. with either electric or manual choke since there isn't any provisions for a heat activated choke.

But that is o.k. since you are saying that you are in need of a new carb. anyway.

And an electronic ignition set up would be worth the money.

[6packdart]

Is there any carb that would work better on this motor ,I was thinking either 650 or a 700 cfm ? When they put the car back together I had them change the converter from the 3500 stall because I didn't like the way the car seemed to scream when on the highway. If I do go to the dual plane intake should it be cast or aluminum ( do they come in aluminum ? ) I would like to keep the weight down ( it's an age thing HA ! HA !) Yes she is my daily driver whenever the weather allows . I 'm trying to learn all I can so that I don't make the same mistakes when the conv. which is in the process of be stripped down now goes back together.

[d.friction]

Go with an aluminum dual plain and a vac. secondary carb, a 650 should be just fine anything bigger than a 700 will be too much. Holley use to make a bad ass 600cfm vac. carb with anular booster. On the intake you might also want to look into a high rise dual plain manifold.

[jasontlit]

The ED Air-Gap seems to have the best of all worlds...Aluminum, dual plane, hi-rise, divorced runners.

Ok, the runners aren't TOTALLY divorced but somewhat anyway.

Square flange carb base on the Air-Gap, so a Thermo-quad is basically out.

Which carb to purchase is a topic that will go on and get debated extensively.

Right now I'm using an Ed permormer. I'm not in love with it and am not loyal to it or the brand. It hasn't given me any problems as of yet. It is based on a carb that a lot of Mopars had back in the day (Carter AVS, AFB).

The last time I had a Holley...I had put it on a tuned up well running motor, and it backfired immediately. So much for the power valve! I should have left the Thermo-quad on there! Actually, it was probably my fault I just didn't know it at the time.

A Demon is probably in my future.

Hope this helps ya!

[roadracerjeff]

Yes, by all means, go with an aluminum dual plane intake -Edelbrock Performer RPM Air Gap or Performer RPM or Weiand Stealth. No bigger than a 650 CFM carb. The 600 CFM Edlebrock would do the job for not much dough, around $250. For more performance, I'd go with the Barry Grant Speed Demon 650 with vacuum secondaries -about $400 though, but will make better use of the intakes we're talking about. Good luck,

[t Hand]

If you drive in the cold, the Air Gap will tend to make the engine stumble when first driving; they have no crossover heat and trust me, with the carb. jetted close to correct, it is cold blooded. Runs great when warm!

[jasontlit]

Very good point, t Hand.

[dwc43]

Originally posted by 6packdart
Ok ,please forgive a mistake or two , this is new to me and the guy's around here just smile and say I wouldn't understand it anyway,so here is what I would like advice on . I have a 69 Barracuda Fastback that is running a mod. 318 that has a edelbrock streetmaster single plane aluminum intake on it , should I keep this intake or would a dual plane work better on this motor? Here is the information that I do know about my motor:doner block is a 1979 casting that was bored .040 the 360 heads were done .020 , main .010 , con. rod .010 ,double rolling timing chain & gears , 360 valves, the cam has a lift of .286 on int. with .296 on exh. valve lift is .429 on int. .444 on exh. lobe ctrs. is 112 on int. 116 on exh. I'm running a 625 carter (which needs replacing ), 360 exhaust manifolds with 2 1/2 " pipes and just enough muffler to make her legal (which isn't much ! ) springs and lifters I'm not sure about ,compression ratio is roughly 9 to 1 ( ? ) , a 2500 stall torque , 727 tranny (console shift ) 8 3/4" sure-grip with 323 gears . Oh ! and it has a single point distributor. This motor is working fine at present after a few adjustments were made , so should I keep the single plane or be a good wife and do the swap hubby wants to the cast dual plane ?

You have a nice combo, but here is what you reallly need to make it run right. Loose the intake and carb quick. Get you a Weiand Action plus dual plane intake. IT is the best small block intake for yopur 318 period. The air gap is not suitable for the 318 period. IF it was a 360 I might say yes to it if it were moded enough. Next get you a stock 800 cfm Thermoquad. The 600's and 50's are too small. Teh thermoquad is more throttle responsive than any holley anyway. We run the 800 thermoquads on all of our race cars rule permitting of course and they work great. They were stock on your 318 aand 340 and 360's too.
Next loose that single point dist. Get you a magnetic pick up dist. and add the recurve springs from Mopar. Get them at your dealers parts counter. Then add a msd6 for your ignition. IT will start easier and add some power to it. You will also be able to open your plug gap up to .045 with the msd ignition. Add a set of Hooker or Hedman 1 5/8 street headers to you set and an H pipe to your exhaust. The H pipe will increase low end torque and add another 3 to 7 hp to the mix.
Get this added to your mill and you'll be able to beat up on those chebby boys.

[rumblefish360]

I gotta go with dwc43 on this stuff. Your street master intake is a shallow single plane intake that is old and out dated. The Factory cast iron unit will do fine on top with cam's silghty bigger than stock. But thats as far as it goes.
Heres the real trick, You said the heads were done. Would that be stock rebuilt or ported? And how much porting was done. Also, would you know the duration at .050 on the cam. The advertised numbers are large, which might not be the case for the @ .050 numbers. (This info might be on the cam card if you still have it or at the manufactures web site/book.)

You also stated it has 360 valves. I assume that it has 1.88 - 1.60 valves in there.
Etiher way, I'm with the Weiand and T-Q carb. If a Holley or other square flanged carb is what you have your heart set on, then a cfm rating off 650 max or less will do.
With the dual plane, you'll pick up more torque on the bottom end. Just make sure it has a heat cross over since it can get cold where you are. The air gap will take awhile to warm up. I run the heat cross over here on Long Island New York on the every day rides.)

Seeing the age of the cars sitting time, you might want to replace the springs.

(Would that be motor bike riding instuctor? Or horse?)

[6packdart]

Hi Guy's , Sorry I didn't get right back to you I've been away to car shows all weekend , the little green fish took best of show for the 60 to 69 class over all the other make's , it was the biggest class there in a show of over 260 cars ! Not bad eh ! Anyway , how come no-one likes the single point dist. I havn't had a problem with mine , the car came with it and I'll keep it if I can or maybe change to a dual point dist. . There just isn't room for headers in this car without sacrificing something I think? and the added 3 to 7 hp to beat the chebby guy's that I know, isn't needed , they won't play with me , they think I'm nut's , plus the fact that I can throw 80 lb bales of hay around scares the shit out of them ! ( no ! I'm not 6'8" 250 lbs , only 5' 7" 160 lbs ! ! ) ok the heads were ported , how much , I'm not sure , I do know that they cracked the head into the water jacket on one and were going to try and weld it to save doing another head but I wouldn't take the repaired head so they had to do another one . I 'm also not sure on the size of the valves , the work order just gives a part #for both the int. and ext. . Just what the hell does "square flanged " mean anyway ( remember NEW GIRL here ! ! ) is it refering to the bottom lip that would sit on the intake or what ? I couldn't find it in my books anywhere ! The duration at .050 is int. 209 and is 220 for exh. Oh and I don't ride motorbike's just horse's

[dwc43]

There's room for headers. They make them for your car. Points will bounce and burn easy too. Msd's produce hot sparks and multiple sparks from idle to 3000 rpm. They will increase milage slightly and produce a better flame front in the cylinder. You can also run more plug gap which also helps promote better flame fronts. They are also more reliable and actually help you make more hp. If chebby boys want come out to play go after the ferd guys then.

[6packdart]

How or where in this car could you put the MSD so that someone just glanceing in wouldn't see it ? Is this possiable to do ? could it be put on the firewall on the inside of the car ?

[dwc43]

We mount ours upside down under the dash and run all he wires through a rubber gromet in the firewall right behind the dist. with the coil mounted just above it so no one can even see the wires. Plus it keeps heat away from it that way. Makes it live longer. I have a msd 7al2 that's 6 years old now and still runs like new.

[6packdart]

Is there an opening there all-ready or is it nessary to drill one because I think I could live with it done up that way. This would hepl in starting the car right? ?

[dwc43]

There should be on near there. And yes it will start ten times much easier.

[rumblefish360]

( remember NEW GIRL here ! ! )
Ouch! I remember, but, I have met girls that can drive better, know more, and are stronger than me. Newbie or not to cars, if you don't understand something, just say so. I'll be glad to clear it up. I have know idea how much you know.
A square bore carb is a typical Holley or Carter AFB/AVS. The throttle bore (Holes) are about equal in size. A spread bore carb is smaller up front in the primarys and larger in the secondarys, Carbs of this nature are the Thermo quad and the Rochester. Because of there off set in bore size, the space on the carb mounting pad is spread out to fit the secondarys.
On the intake manifold, a square bore intake has a square hole where the cab sits.
A spread bore intake manifold has larger openings in the rear to accept the larger secondaries.

I placed my MSD ('73 Cuda) under the battery tray. It can be seen only from the passenger side, front off the car.

Excellent books to read are the following;
How to rebuild my small block chrysler
How to hot rod your small block chrysler. by Larry Shepard.
MoPar Performance's "Engine" book. Just a year or 2 ago, they split up the book into engine size. So you'll need the small block book for the "LA" engine. Not the Magnum engine., Also,
MoPars Chassis book is very good to have.
Last but not least, a book on your car itself. Chrysler can make you a reprint of the service manual. An excellent excellent book to have at your side.

[littlecampbell]

What about the LD4B intake? (just happen to have one in the barn) ....If you had a 340 I would say an Air Gap.
Why fool around looking for a T-Quad and pay someone to set it up and if you need parts in Nova Scotia good luck. I know Rumble and dwc43 are partial to the T-Quad but you guys have the experience tearing them down and setting them up.
6packdart sounds like me a few months ago,(actually i'm 6"s taller and 90lbs heavier) ....I got a used 750 AFB and got the rebuild kit, took it totally apart and put all new parts in and havent had a problem all summer..2000 miles and no bogging.
Listen to Rumble on the books they are all great reading and very informative.
If you must have a T-quad Mr.Mopar from Alberta has one but he would probably want your first born
Oh yeah, get headers, theres room...its a must.
Got any pics of the "Green Fish"?....Cheers Maritime man!

[6packdart]

We get T.V. commercials for your beer here they're a bit strange but cute ! . As far as getting engine parts , thats no problem , lots of good stuff still around if you know the rigth people I have a freind in his 70's who use to work on the Hemi Under Glass and raced mopars for years , he's a great guy and helps me when he can. Now ! body panals ! those are real hard to come buy here ! I have a few books like an interchange manual and service manuals for the 68 cuda and the 85 D150 also a few restoration books . And trust me ! no one but his girlfreind would want my first born , he cost's to much to feed ! ! I think that the headers will have to wait , maybe for the truck . I have lots of pictures of the green fish , but wouldn't have the foggist idea how to get one where you could see it ? Ok here's another ? for you guys the exhust manifolds on the cuda were painted with a high heat manifold paint but it burnt off after a while, got any ideas, I know there is powder coating that could be done here, but is there a paint that I could buy to do this job myself ? Thanks Rumblefish , I now know that I have a square bore carter carb. and my freinds chebbie has a spread bore rochester. The new girl is learning Eh ! !

[dwc43]

Check Year One. THey have some manifold paint that's supposed to look like cast iron. It's a brush on quart can.