And tunnel rams!!!!!
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LA 340 Intake Manifold
- Thread starter 340inabbody
- Start date
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Hook the PVC to the back port on the holley carb.
Dartswinger70
Well-Known Member
340 in a B Body? i almost did that once I had a 69 Coronet 500 with a 318 got to readin up on 340s then I found a 70 Swinger 340 for sale. I asked about "just the engine...?" guy siad "No I want to sell the whole car..." I was like "ok" .
$1000 dollars later I was towing home an H code swinger and parts. I eventually got rid of the B body it had too much rust for my skills at the time but today I wish id kept it. anyway Id run a dual plane on the street i know its a generic answer but I hear many say single planes are terrible on the street and it makes sense they are designed basically for best performance in the upper RPM range
$1000 dollars later I was towing home an H code swinger and parts. I eventually got rid of the B body it had too much rust for my skills at the time but today I wish id kept it. anyway Id run a dual plane on the street i know its a generic answer but I hear many say single planes are terrible on the street and it makes sense they are designed basically for best performance in the upper RPM range
340inabbody
Well-Known Member
The power brake vacuum line is connected to that as a dedicated port. I hear you shouldn’t T them……
I would not "T" them either.
I would drill and tap the manifold for a 1/4" NPT and put a fitting for the power brakes.
Dale Davies
Well-Known Member
IMHO the Edelbrock RPM Airgap is the preferred manifold for street, especially in southern locals where summer heat is higher.
The Holley double pumper carb gives good throttle response at the expense of fuel economy. For road racing or circle track the throttle response is of prim concern. For drag racing especially in an automatic transmission car there may be a small advantage just as the light turns green and the throttle is planted in the radiator. Once the fuel flow catches up to the air flow, single or double pumpers are on equal ground.
For street and to work the best with the Airgap manifold, an Edelbrock AVS2 carburetor provides better primary fuel atomization. This will aid driveability, throttle response, fuel economy and emissions.
The Holley double pumper carb gives good throttle response at the expense of fuel economy. For road racing or circle track the throttle response is of prim concern. For drag racing especially in an automatic transmission car there may be a small advantage just as the light turns green and the throttle is planted in the radiator. Once the fuel flow catches up to the air flow, single or double pumpers are on equal ground.
For street and to work the best with the Airgap manifold, an Edelbrock AVS2 carburetor provides better primary fuel atomization. This will aid driveability, throttle response, fuel economy and emissions.
Gotta agree with this one in print.
If you work on the Edelbrock enough, you can certainly get a really good throttle response.
Mark Merrill
Member
Mark Merrill
Member
I purchased one of these manifolds and the bolt holes didnt line up with my X heads. Almost crossed some threads. Looks to me like these fit a small ford too.
Professor Fate
Push the button, Max...
Not even close- the Ford has individual runners, a horizontal left side thermostat and a front distributor. I've run these on several different engines with no issues, but manufacturing mistakes happen. Sadly, its not just the cheap units anymore- I've had to send back Eddy manifolds on two occasions...
340inabbody
Well-Known Member
Just out of curiosity what intake gasket mfg do you guys use?
Dartnut
Don't hate me because i'm beautiful
IMHO, you would be better of using a fairly mild 440 big block for what your stated needs are.
The problem with this though is that you would have to change a lot of things to big block parts like headers, transmission, motor mounts, engine brackets, etc.
In the long run, you would be better off and it would clear the hood easily if you don't go wild on the intake height.
However, you would have to change your user name though...lol
The problem with this though is that you would have to change a lot of things to big block parts like headers, transmission, motor mounts, engine brackets, etc.
In the long run, you would be better off and it would clear the hood easily if you don't go wild on the intake height.
However, you would have to change your user name though...lol
340inabbody
Well-Known Member
Yeah I have some $ invested into this small block set up. If I had a lot of money I might consider it but I am like most of us here fund limited.
Question is why would a big block necessarily be lower than a small block? I have not seen a discussion or dimensional evaluation of this before anywhere……..
Price check parts available.
340inabbody
Well-Known Member
Lower in height that is
340inabbody
Well-Known Member
Check pricing on parts, sb vs bb.
Dartnut
Don't hate me because i'm beautiful
All that I was eluding to as for hood clearance was the fact that several B-Bodies like yours were built with a big block from the factory and that a ''fairly'' stock 440 would not need as much performance work done to the inside of the engine as the 340 to equal the power output and drivability that you require.
A mild 440 with a dual plane intake that is roughly stock height should easily make 1 HP per cubic inch with headers, some mild port work, and 9 1/2 to 1 compression ratio , and you would have to breathe on a 340 quite a bit more in comparison to make that level of power and the 440 would have gobs of torque compared to the 340 at this level.
You could sell the 340 to someone for a pretty good sum to offset the costs.
Now all of my suggestions go out the window if you REALLY want to keep the 340 in the car...
Beautiful car by the way!
340inabbody
Well-Known Member
Thanks yup understood. Where I was going with the build was a “what if” Plymouth did the “Spirt Satellite” right and put a 340 in it instead of the 318 that was in it. Why call it a Sport Satellite if there is not difference other than GTX a trim package. It was a drop in to my existing drivetrain as well. I know that it will have less torque than a big block and I am ok with that. But I definitely hear what your saying and it does make sense!
I love this stuff! Lol
I like “What If’s.” Great fun. I wouldn’t mind a “Sport Satellite” as a Road Runner or GTX, my bucket lists cars, are a bit to pricey for my wallet.
340inabbody
Well-Known Member
So I wanted to follow up with you guys on this. I was able to get my hood on to test fit with the M1 high rise manifold. It fits with the spacer removed. I will replace the manifold with an air gap later once most of my re-assembly work is complete. Still slow going due to the heat. Thanks for your support and help on this guys!
The engine will move around under power.
340inabbody
Well-Known Member
Yes that needs to be assessed. The hinge that just clears the air cleaner is not how it will sit. Its all the way down and not how it will sit. It will be up and bolted to the door. There is about 1/2 to 3/4 inch clearance as it with no mods.
340inabbody
Well-Known Member
Just out of curiosity….are the exhaust manifolds header compatible on a 340 vs Magnum 360? Meaning can you swap headers from a 340 to Magnum?
Yes, I ran LA headers on my 360 mag.
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