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small block appearance

Cornpatch MO

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I'm not familiar with Mopar small blocks except LA 318. Does a LA 318 and a 340 look the same? Would a 340 six pack intake fit a LA 318? Is there a three -two bbl intake that would fit a LA 318? I am getting idea's of a sheep in wolves clothing ! ...............................MO
 
318/340/360 look the same. "Technically" a 340 six pack setup will bolt up to a 318....however.....340/360 have larger intake ports so 1/3 of your airflow from the six pack would "hit a brick wall" trying to flow into the smalleer 318 intake port. BUT.....340/360 heads will bolt up to a 318 and solve that problem. There is no 318 six pack intake that i am aware of.
 
Even if it would fit......the engine would be severely over carbureted. Remember that an i.c engine is just an air pump. you can only put in what can come out. It would be like a funnel. A wide opening at the top (intake) and a small opening at the bottom ( exhaust/exit ).
 
Isthere a three -two bbl intake that would fit a LA 318?

Yes. Why you would do it is beyond me.
 
The true T/A and AAR 340's were in fact a 340 destroked to 305. With the right heads , cam and compression ratio, a 318 should run great with a 6 pak intake. At that point, the same money could have been spent on a 360 and a better return on your horsepower money would be attained. But, it would be cool do have a hot 318 or slant 6 for that matter.
 
You could always put one on and unhook the for and aft carbs. It would run like poop but would look great!
 
Yes, parts do interchange... for the most part. For a six pack intake, or big single quad manifold, you'd want ports to match up between heads and manifold.

It's possible to put 340 heads and a 6 pack manifold together, but be prepared to jet down those carbs. Headers would also be recommended on an engine with that size of induction...

Personally, if I were gonna build a small block 6 pack setup, id find a good 360 block to build a stroker motor with. 4 inch crank to bump the c.i.d. to about 410. It'd be enough engine for the 6 pack setup to achieve its potential.
 
I'm not familiar with Mopar small blocks except LA 318. Does a LA 318 and a 340 look the same? Yes. Would a 340 six pack intake fit a LA 318? Yes. Is there a three -two bbl intake that would fit a LA 318? Yes. I am getting idea's of a sheep in wolves clothing ! ...............................MO
Go for it! It could run quite well and other than casting #'s you couldn't tell the difference.
 
Thanks all for your reply's. I did say " a sheep in wolves clothing" If you will note, I have a Fraud Thunderbolt hood bubble on my 64 Dodge. Part of the reason is mid 60's Nostalgia cool air intake , and, I don't do things like everyone else.
My plan: to make my 68 Sattellite look similar to the new ordered 68 1/2 Roadrunner 2 dr hdtp with optional interior and exterior trim. Broke my heart when I had to sell it after having it for just a short while. This car will be built to cruise long distance. A/C ,power steering, stock Satty rear gears, stock 904 tyranny , and the stock LA 318. If people want to look at the engine, I would like the looks of a 340-360 6 pack with just the center 2 bbl being functional. That 19-20 MPG on pump gas appeals to me. .........................MO
 
Thanks all for your reply's. I did say " a sheep in wolves clothing" If you will note, I have a Fraud Thunderbolt hood bubble on my 64 Dodge. Part of the reason is mid 60's Nostalgia cool air intake , and, I don't do things like everyone else.
My plan: to make my 68 Sattellite look similar to the new ordered 68 1/2 Roadrunner 2 dr hdtp with optional interior and exterior trim. Broke my heart when I had to sell it after having it for just a short while. This car will be built to cruise long distance. A/C ,power steering, stock Satty rear gears, stock 904 tyranny , and the stock LA 318. If people want to look at the engine, I would like the looks of a 340-360 6 pack with just the center 2 bbl being functional. That 19-20 MPG on pump gas appeals to me. .........................MO
If you're just gonna use the center carb... you're wasting 1000 bucks. Each of those carbs are very expensive... take that into consideration. You can make the entire thing functional... but you'd have to jet it down quite a bit.
 
Drobertson, burntorng70 are dead on right. As is
Purple beeper except the 1/3 port comment. That is a bit much but he is correct on it.

Slapstick the nay sayer! It'll work. Seen it done more than once.

Don't "Unhook" any of the carbs on a 6 pack! You need to jet the carbs correctly! PERIOD!

It total, after converting the 2bbl. rating of the 6 pack, it equals approximately 955cfm in 4bbl. terms. Since it is vacuum operated, you will use the outboard carbs when needed.

I do caution you on the thinking you'll get high mileage and super power as this is not the case. You can get 2bbl. mileage if the rest of the engine and drivetrain are set up like a 2bbl. car. Then the outboard carbs are basically useless and provide very little to the overall package. At this level, your better off with a small 4bbl. Like a 450 Holley or 500 Edelbrock.
 
Of course you can do it. But it doesnt mean you should.
You could put on a dual quad tunnel ram with Dominators. But why?
Spend the money on something functional.
 
I have an an old Edelbrock LD4B intake manifold that was discontinued back in the eighties. These were specially designed to be used on a 2bbl 318 engine. It has the small 318 port size where the manifold meets the intake port. It then opens up on the way to the carb plenum. This manifold has not been modified in any way. No leaks, stripped holes. You will also need to change over to the 4 bbl carb and trans linkages as they will be in a different location on the manifold.
 
Drobertson, burntorng70 are dead on right. As is
Purple beeper except the 1/3 port comment. That is a bit much but he is correct on it.

Slapstick the nay sayer! It'll work. Seen it done more than once.

Don't "Unhook" any of the carbs on a 6 pack! You need to jet the carbs correctly! PERIOD!

It total, after converting the 2bbl. rating of the 6 pack, it equals approximately 955cfm in 4bbl. terms. Since it is vacuum operated, you will use the outboard carbs when needed.

I do caution you on the thinking you'll get high mileage and super power as this is not the case. You can get 2bbl. mileage if the rest of the engine and drivetrain are set up like a 2bbl. car. Then the outboard carbs are basically useless and provide very little to the overall package. At this level, your better off with a small 4bbl. Like a 450 Holley or 500 Edelbrock.
Does anyone read a whole post before they offer advice? LOL. I am not talking "super power" nor am I talking the actual original 6 pak carbs. I bet there is a three duece intake that will fit a 318 block, and I also bet there is a aftermarket 2 bbl( if not the Mopar 318 stock two bbl. ) that will fit. My current LA 318 has all the power I would want, and it will get 19MPG...........MO
 
I have an an old Edelbrock LD4B intake manifold that was discontinued back in the eighties. These were specially designed to be used on a 2bbl 318 engine. It has the small 318 port size where the manifold meets the intake port. It then opens up on the way to the carb plenum. This manifold has not been modified in any way. No leaks, stripped holes. You will also need to change over to the 4 bbl carb and trans linkages as they will be in a different location on the manifold.
Thank you, I am just kicking around an idea. I like to make people say hmmmmm. That is why on my 64 Dodge, the (413) single 4 bbl is painted Mopar orange ( the factory never had that engine painted orange) the valve cover decal say's " Police Pursuit" ( the factory never had a cop engine with a decal ID) There is no regulators, relays, or wiring on the firewall or fenders, NO billit, chrome, polished aluminum, or braided hoses, no heater hoses, appears to be a stock points distributor and coil, Fresh air induction from the inner headlights..Stark as a black piece of paper. IMO making a statement without saying anything......................MO
 
I have an an old Edelbrock LD4B intake manifold that was discontinued back in the eighties. These were specially designed to be used on a 2bbl 318 engine. It has the small 318 port size where the manifold meets the intake port. It then opens up on the way to the carb plenum. This manifold has not been modified in any way. No leaks, stripped holes. You will also need to change over to the 4 bbl carb and trans linkages as they will be in a different location on the manifold.
I may be interested in buying that intake. I may have to come up with a plan "B" if a three duece intake isn't feasible.....Send me a conversation message please?.........................MO
 
With total airflow around 955 cfm, the six pack is totally doable. Plenty of 318's came from the factory with Thermoquad carbs which were rated at 900 cfm total airflow. A good set of 340-360 heads would be necessary. However, to make use of the extra airflow, raising the compression, cam upgrade, and headers would be in the cards.
 
Iirc those engines came with the baby TQ. My research shows they flowed 520 cfm.
 
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I have seen data in the 737cfm range for the small TQ. Nothing lower. QJ's on the other hand did flow less on some models.
Other TQ models;
IIRC, an actual 787 for the large TQ
850 & 900/1000 for the "Race" TQ
 
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