Recommended 4bbl carb for stock 318

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The thing about double pumpers is when you whack it WOT, you get all 4 barrels.
If you do this at a dead stop with an 1800 TC, and 2.76s, and it doesn't spin, you are almost guaranteed a big fat bog. Now with a 2400TC and 3.55s, she is almost guaranteed NOT to bog, and you will have instant rpm. As you release the throttle a little, first the secondaries will begin to close...... so you can control the severity of the wheelspin by dialing out throttle. This makes controlled sliding and drifting possible, and also restarting spins at speed.

The thing about VS carbs is when you whack it WOT, from a dead stop,you get just 2 barrels. If you do this with an 1800TC and 2.76s,you will have to wait for the secondaries to open. Maybe a long time, since it ain't gonna spin until the Rs get up a little, say around 200/220 ftlbs or something like 2200rpm, so wait it out, this is about 22 or more mph. Then they will finally be open, hopefully all the way; but by this time it's doubtful a teener can spin the tires.
But again, with a 2400TC and 3.55s, you have enough TM (Torque Multiplication) to initiate a spin from a dead-stop, and so the Secondaries will open, allbeit not as rapidly as a double pumper.But if you back out of the throttle, they will close faster than a DP, and you will have to wait again, just a bit, for them to re-open. But if your wheels have stopped spinning, it's doubtful that you can restart the spin. This makes drifting and sliding and fishtailing practically impossible unless you keep it floored and work the brakes, and that only works until the brakes puke. All-in-all very unsatisfactory and sometimes downright embarrassing, like when you have a car-full of men totaling an extra 500/600 pounds; just fogetabowdit. Or like halfway thru a sliding corner and for some reason you have to lift a bit. Now your steering is close to full-lock, and as soon as the tires stop spinning, you are off-roading, and hopefully just in the weeds. On two wheels this would be "high-sided", and usually ends up with flight-time and personal injury.
Like I said, I wouldn't buy one on purpose. They are ok for straight-line work, and a lil extra in passing gear.

Well this carb turned out to be a 600CFM with VS's, but I understand the differences better now between double pump and VS's, and why VS is recommended for mild street driving, and I see why double pump is best on throttle control for power
I defiantly understand the physics, I just never really thought about it until you pointed it out, which was a good thing. As I said I planed on changing the rear gears at some point, but never really considered the effect of the torque converter stall speeds. And I assume 1800TC is the same as saying 1800 ftlb stall speed, but I can see the change to a different gear and stall speed having a better affect on power performance. And if I do use this carb I can upgrade something else, gears, cam, TC, but now I'm not sure what to go with first? Gears or cam?
 
Again his is going to bring it to the owners Besides I'm not looking for a street/strip car just a good driver

I am going to try it out tomorrow night. And I realized my intake isn't a square bore though, it's an oval from a 71' 340 that seems to have been only used for on year? odd?. But that's no problem I have an adapter from the 850CFM attempt a while back. Also the carb includes different pivot arms, a stock thermo coil adapter, and a couple other little things. So ill let you know in the evening how it goes.
View attachment 1715227382 View attachment 1715227383 View attachment 1715227381 View attachment 1715227384
That is the same intake I have same casting number and all!
 
Well this carb turned out to be a 600CFM with VS's, but I understand the differences better now between double pump and VS's, and why VS is recommended for mild street driving, and I see why double pump is best on throttle control for power
I defiantly understand the physics, I just never really thought about it until you pointed it out, which was a good thing. As I said I planed on changing the rear gears at some point, but never really considered the effect of the torque converter stall speeds. And I assume 1800TC is the same as saying 1800 ftlb stall speed, but I can see the change to a different gear and stall speed having a better affect on power performance. And if I do use this carb I can upgrade something else, gears, cam, TC, but now I'm not sure what to go with first? Gears or cam?
Every one is gonna say gears!
 
What is that vacuum port plug in the intake runner? Looks like a bolt and washer. Watch for vacuum leaks there.
If it the pic with the casting number that's the water neck / thermostat no a vacuum port, sorry I should have taken a pick of the whole thing
 
If it the pic with the casting number that's the water neck / thermostat no a vacuum port, sorry I should have taken a pick of the whole thing
Yep that's it. Sorry. It looked like a vacuum port on the rear for the power brakes. I Can see the edge of the thermostat housing now.
 
Again his is going to bring it to the owners Besides I'm not looking for a street/strip car just a good driver
]
I was just answering your statement/question about the vacuum secondary being "better for fuel mileage" statement you made.
 
You are making things way more difficult than they need to be.
What are you going to do for linkage and kickdown ?
Have you thought of that ?
And a smog egr thermoquad intake teamed up with a Holley ?
Very interesting decisions. Its like you got some very informative information for your question, and then have gone in a complete opposite direction.

The lure of a deal trumped the previous 62 posts in this thread.
 
You are making things way more difficult than they need to be.
What are you going to do for linkage and kickdown ?
Have you thought of that ?
And a smog egr thermoquad intake teamed up with a Holley ?
Very interesting decisions. Its like you got some very informative information for your question, and then have gone in a complete opposite direction.
The Carb has a universal install kit, and has number different linkages to swap in, including the Plymouth arm for kickdown throttle cable. The theory would be the carb is able to move the fuel mixture either way, however I do think it may be a bit better due to VS's being smaller and the adapter plate used creates a nice flow change directly from the butterflies down to the manifold with no restrictions and it's an additional 1/2'' taller helping run cooler. Also, It' wasn't an interesting decision really. The manifold has been around for a while with my grandfather from some other car a long time ago, so it's the "free manifold" decision with my theory that says just stick with this intake.
opposite decision? this had initial suggestions that I used for the first end decision LOL, but when big money savings comes into play I couldn't resist. And really that's the only difference from my initial question of the post.
Also I'm pretty sure the intake manifold it's not a California (smog) intake, I didn't notice any added when I looked it up on this chart
If the chart is incorrect, please let me know so I can have as much info on LA block as I can

LA Engine Intake Manifold Casting Numbers
Casting Number
Engine-bbl Year Remarks
2465726 273-4 1965
2536636 273-4 1966
2536536 273-4 1966-67
2536771 273-4 1966-67 Calif. Emissions
2531915 340-4 1968
2531914 340 1968-71
2843683 318-2 1969-70
3462848 340-4 1970
3418681 340-6 1970 Alum. AAR & T/A
2951185 318-2 1970-71
3512100 340-4 1971
3614025 340-4 1972
3671918 340-4 1972 Calif. Emissions
3671918 340-4 1973
3512099 340 1971-73
3698437 360-4 1973
3698434 360-4 1974
3698435 360-4 1974

Let me know, thanks
 
The lure of a deal trumped the previous 62 posts in this thread.
I don't want to put it that way...
If could afford lots of parts or even a few at the same time I would. If an opportunity arrives to save some money I have to take it these days. But no question, if I was still going to be paying for a carb it would be the 600CFM Holley Demon Street Performer, and changed from the Edlebrock due to interchangeable parts (new, larger needles and seats as well as jets) and cost.

Sorry for what seems to have made a run around, there have been good points that drew a bottom line of preference. So this near free carb can work just as well as others for what I'm looking to "start" with. with that info it's seems like a starting point for jumping into this upgrade
 
Just read the whole thread. My head is spinning. Your all over the place bud. Got nothing for you, you seem to have it all figured out. Back in the day I had a stock 1970 318 Dart with an Ede Performer and an Ede 600, and that little bugger would burn rubber all the way down the street. But what do I know.
 
Just read the whole thread. My head is spinning. Your all over the place bud. Got nothing for you, you seem to have it all figured out. Back in the day I had a stock 1970 318 Dart with an Ede Performer and an Ede 600, and that little bugger would burn rubber all the way down the street. But what do I know.

All over the place?
Yeah, the choices of carbs change? That's the point of finding what's best for the current situation.
I mean there was the first choice of (Edlebrock) was based on people like yourself who used it and have had no trouble. Next there's the (Holley Demon), same deal and also a suggestion for Themoquad. But no real fight against the Holley Classic 600CFM 4160.
I initially went with the Edlebrock because of the first few posts being very adamant on satisfaction. I was then swayed toward the demon due to suggestions and what I found to be better internal upgrades available for the future. And now to the choice of the 4160 is just the "money savings" and the fact the it should work fine.
So there's the loop around, I hope it helps. I guess this means I should start a new initial OP reply with my thoughts for the current standing (ie. current carb and intake removal to switch to the available intake and carb) asking what are the drawbacks in the 4160 vs. the Edlebrock, Demon, or others
 
Well this carb turned out to be a 600CFM with VS's, but I understand the differences better now between double pump and VS's, and why VS is recommended for mild street driving, and I see why double pump is best on throttle control for power
I defiantly understand the physics, I just never really thought about it until you pointed it out, which was a good thing. As I said I planed on changing the rear gears at some point, but never really considered the effect of the torque converter stall speeds. And I assume 1800TC is the same as saying 1800 ftlb stall speed, but I can see the change to a different gear and stall speed having a better affect on power performance. And if I do use this carb I can upgrade something else, gears, cam, TC, but now I'm not sure what to go with first? Gears or cam?
I'm not sure what you are saying here, only hiway tractors, and such, make 1800ftlbs
An 1800TC is rated to stall at 1800rpm with a given amount of input torque. Stall-speed is what the the engine revs to at zero mph when you floor it.
Your engine has a torque curve that starts at the stall rpm and ends when you shift. It varies from a low number at low-rpm to peak at a higher rpm when the engine reaches peak efficiency, and then begins to decline on it's way to the shift rpm.
One cam-size is an increase of about 7* at .050.
Each increase in cam-size will move the power-peak up about 200 rpm
Beginning with a stock teener cam of 240*adv , and for street, ending around a 276*adv, that makes about a 6 size range for a street-teener. Therefore,
Peak efficiency usually falls in the range of 1200 to 1400 rpm centered somewhere around 3800, and depends principally on the cam for a given sized engine. Peak power usually falls about 1500 rpm later, but depends on more factors. The shift rpm is kindof dictated by the transmission ratio splits, but sometimes other factors reduce that.
Put simply; if you move the power peak up 200 rpm, you will lose a minimum of half that at the bottom,probably more.The 268 cam is about 4 sizes bigger than stock, moving the power peak up about 800 rpm, and going soft at least 400 rpm sooner. The factory 1800TC while not particularly soft for a DD, for performance is already 400 to 600rpm short of where it should be. So that make your new TC requirement for the 268* cam,to be about; 1800+600+400=2800rpm.
I got my first 2800 in about 1980, for a 225 in a 69 Barracuda. That TC has been with me ever since, going from one engine to the next,in almost every DD,ever since.It's got a great little "hit". At that time it was called a "Dirt-Jerker 2800". You need one.lol The company I worked for at that time, made those.
 
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I'm not sure what you are saying here, only hiway tractors, and such, make 1800ftlbs
An 1800TC is rated to stall at 1800rpm with a given amount of input torque. Stall-speed is what the the engine revs to at zero mph when you floor it.
Your engine has a torque curve that starts at the stall rpm and ends when you shift. It varies from a low number at low-rpm to peak at a higher rpm when the engine reaches peak efficiency, and then begins to decline on it's way to the shift rpm.
One cam-size is an increase of about 7* at .050.
Each increase in cam-size will move the power-peak up about 200 rpm
Beginning with a stock teener cam of 240*adv , and for street, ending around a 276*adv, that makes about a 6 size range for a street-teener. Therefore,
Peak efficiency usually falls in the range of 1200 to 1400 rpm centered somewhere around 3800, and depends principally on the cam for a given sized engine. Peak power usually falls about 1500 rpm later, but depends on more factors. The shift rpm is kindof dictated by the transmission ratio splits, but sometimes other factors reduce that.
Put simply; if you move the power peak up 200 rpm, you will lose a minimum of half that at the bottom,probably more.The 268 cam is about 4 sizes bigger than stock, moving the power peak up about 800 rpm, and going soft at least 400 rpm sooner. The factory 1800TC while not particularly soft for a DD, for performance is already 400 to 600rpm short of where it should be. So that make your new TC requirement for the 268* cam,to be about; 1800+600+400=2800rpm.
I got my first 2800 in about 1980, for a 225 in a 69 Barracuda. That TC has been with me ever since, going from one engine to the next,in almost every DD,ever since.It's got a great little "hit". At that time it was called a "Dirt-Jerker 2800". You need one.lol The company I worked for at that time, made those.

Because I now know for sure I will be adding a new torque converter to the mix... To avoid further confusion I think this portion is going to have to take a back seat for a bit until my head is cleared of the fuel and air issue and is cleared up with everyone else.
Sorry I was thinking rpm in my head but put ftlb.
That gave even more to think about with more info.
Again thanks, that's been a lot of info and it's good to know what types of numbers I will be looking at when I hit that step.

Keeping in mind this is my first ever automatic tranny, I do want to be sure I can utilize what I will have get the proper understanding.

My issue seems in the TC itself and how the TM works with the stall speed (bogging, quick reaction, whatnot).
Your last post added even more understanding but more info to process.

I know gear ratio no problem. That's easy to understand ( gear ratio of 2.5:1 is 2.5 turns of the input to 1 turn for the out put ), great for higher speed, not low end torque. Compared to say ( 4:1 ) better for slower speed and low end torque.

If my understand is correct in a manual, each individual gear is also a ratio output to multiply tranny duty for the horsepower vs. torque in the rpm range from the engine to the rear wheels. Say for example 3rd gear is the 1:1 ratio at 3000rpm for 60kph, switch to say 1st gear with the 3:1 at 3000rpm gives 20kph. this compered to 5th gear 1:3 giving 100kph. Assuming this has all been on the same cam and running with a rear gear of 3:1, simply by changing the rear gear ratio up or down you can lean further toward low end slower speed higher torque or high end horsepower and faster speed allowing each individual gear to perform better for torque or horsepower.
The key being finding the correct final ratio's for each application.
Then trying to transfer that power through the clutch ( basically a brake pad and disc ) with springs for locking the two together. And this combination dictates the ability to transfer direct output rpm from the engine to the direct input of the tranny. And this is effected by the clutch using different materials for the disc (organic to Ceramic), flywheel (mild to high carbon steel), and pressure plate spring rate, as well as the number of disc's.
That being said I hope it was correct, but the tranny info will have to wait.
 
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Trying to steer him that way, but it's difficult.
It works, has a manual with a chart.

It's a hot rod'rs carb, I'd just the same recommend the holley 600... but people veer to the shiny.lol I can tune both and get close.....I have my own preference of course.
By finding that carb at a good price, you’ve pretty well decided to go that route with your 4bbl upgrade. Perhaps best to stop second guessing and commit to using that carb. Let us know how your progress is with that one!
Just read the whole thread. My head is spinning. Your all over the place bud. Got nothing for you, you seem to have it all figured out. Back in the day I had a stock 1970 318 Dart with an Ede Performer and an Ede 600, and that little bugger would burn rubber all the way down the street. But what do I know.

After all the great suggestion from you guys. Cost was a contributing factor from the start all along with the size, type, and brand of carb. I am having to go in a bit different direct to maximize my savings for future parts now though,
So...
Currently my decision has landed on the 4160 with the universal install kit, sitting on a 71' spread bore non-smog intake manifold. This has been based on what intake currently have, what carb was dirt-dirt cheap and in hand, and available future funds.
A - Is there anyone who has used this combo and had trouble?
B - Is there any reasons this combo can't be used?
C - Is there going to be any major differences between the 3 different (4160,1406,Demon) 600CFM carbs all with vacuum secondary's? If so, what specifically?

And I will still use the info for a possible future carb when I can afford it.
So from this point, really, the suggestions are now for others to get help as well.

With all the input from everyone here
In a perfect world
I would lean towards the Edlebrock or Demon carb and I would use the suggested information from you guys to find the most recommended carb and combine that with further research on specs to make a decision. Then that carb would be sitting on a light weight, high flow, and low profile intake. Then move onto rear gears, then cam, then the torque converter, and eventually to high flow shorty headers to go with the current dual exhaust.
 
All over the place?
Yeah, the choices of carbs change? That's the point of finding what's best for the current situation.
I mean there was the first choice of (Edlebrock) was based on people like yourself who used it and have had no trouble. Next there's the (Holley Demon), same deal and also a suggestion for Themoquad. But no real fight against the Holley Classic 600CFM 4160.
I initially went with the Edlebrock because of the first few posts being very adamant on satisfaction. I was then swayed toward the demon due to suggestions and what I found to be better internal upgrades available for the future. And now to the choice of the 4160 is just the "money savings" and the fact the it should work fine.
So there's the loop around, I hope it helps. I guess this means I should start a new initial OP reply with my thoughts for the current standing (ie. current carb and intake removal to switch to the available intake and carb) asking what are the drawbacks in the 4160 vs. the Edlebrock, Demon, or others
Ignore the haters. These ppl think money grow on trees when its not their money or their car! I'm with you 100% I understand that there is better out there and probably better fits but I go with what will work (maybe not the best) but i can afford. If it's a difference between the car not running at all or not running to it's full potential but drivable I will take the latter! Seems like some ppl just dont understand what a budget means .
 
Ignore the haters. These ppl think money grow on trees when its not their money or their car! I'm with you 100% I understand that there is better out there and probably better fits but I go with what will work (maybe not the best) but i can afford. If it's a difference between the car not running at all or not running to it's full potential but drivable I will take the latter! Seems like some ppl just dont understand what a budget means .

Well I sure as hell don't. I have several good Edelbrock cores and was going to let him get one for 50 bucks and include the kit I have that I'll never use. But he jumped the gun and got something different. Budget is #1 for me because we've never had money. No need to make blanket statements.
 
Well I sure as hell don't. I have several good Edelbrock cores and was going to let him get one for 50 bucks and include the kit I have that I'll never use. But he jumped the gun and got something different. Budget is #1 for me because we've never had money. No need to make blanket statements.
I wasnt referring to you rrr. Yes I agree with you and the others that the edelbrock is the better choice but he said he got that carb for next to nothing so why are some trolling him. You never said anything negative to him so you know I have nothing but respect for you bud! My comment was not directed towards you at all! Anyways back to carbs.
 
Just have to add my 2 cents. Since you have one of the best ever intake manifolds, keep your eyes open for a good TQ. You can use the OEM choke and pull off. They can be adjusted to run like fuel injection. Had mine in South Dakota and it worked like a charm. If you get a good TQ you will never put that Holley back on. I do understand the budget deal and which ever way you go, I'll second the MOPAR throttle arm, 340 cable bracket and tranny kickdown linkage or cable.
 
I wasnt referring to you rrr. Yes I agree with you and the others that the edelbrock is the better choice but he said he got that carb for next to nothing so why are some trolling him. You never said anything negative to him so you know I have nothing but respect for you bud! My comment was not directed towards you at all! Anyways back to carbs.

It's all good! As they say in da hood. lol
 
Just have to add my 2 cents. Since you have one of the best ever intake manifolds, keep your eyes open for a good TQ. You can use the OEM choke and pull off. They can be adjusted to run like fuel injection. Had mine in South Dakota and it worked like a charm. If you get a good TQ you will never put that Holley back on. I do understand the budget deal and which ever way you go, I'll second the MOPAR throttle arm, 340 cable bracket and tranny kickdown linkage or cable.

I can't disagree here either. He just needs to know the Thermoquad has a learning curve for both building and tuning. More so with tuning. When they are right, they are perhaps the best street carburetor there is.
 
Just have to add my 2 cents. Since you have one of the best ever intake manifolds, keep your eyes open for a good TQ. You can use the OEM choke and pull off. They can be adjusted to run like fuel injection. Had mine in South Dakota and it worked like a charm. If you get a good TQ you will never put that Holley back on. I do understand the budget deal and which ever way you go, I'll second the MOPAR throttle arm, 340 cable bracket and tranny kickdown linkage or cable.
I can't disagree here either. He just needs to know the Thermoquad has a learning curve for both building and tuning. More so with tuning. When they are right, they are perhaps the best street carburetor there is.

I'm not against having a Thermoquad, I asked around for a while locally but no one had an extra carb and online was just overpriced rebuilt or unknown quality used one. Actually I would like to have all three types just to be able to learn more and be able to put a better 2cents in for questions from others.

Well I sure as hell don't. I have several good Edelbrock cores and was going to let him get one for 50 bucks and include the kit I have that I'll never use. But he jumped the gun and got something different. Budget is #1 for me because we've never had money. No need to make blanket statements.
As for jumping the gun, It was because of the low cost. I meant dirt-dirt cheap - I mean I paid nothing other then help clean up.
If you are offering, :poke:I would still love to have the Edlebrock as well. More for learning and fun to rebuild. :)
 
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