LD340 intake mods

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AdamR

AdamR

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Does anyone have any experience with the modifications out lined in the Mopar engine books for the LD340 intakes ? These mods are for running spreadbore (thermoquads) and cutting down the divider. I'm going to be running a TQ from Demon Sizzler and Im debating if I should try the other mods as well.
 
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Adam you know I'm running the LA340 intake. My divider or plentium I believe, was cut dowm and the ports gasket matched to the rpm heads. But I don't recall the specs.
 
Adam, I have a LD-340 with these mods. I would leave the divider in if the cam is small(ish) and street bound. Under .550 lift.

If your trying to produce some serious power with this intake, then that divider mod and port matching is all you'll need to do.

Before you mill the divider down, try some spacers under the carb. Mopar has 1/4 inch spacers for the T-Q. I do not know the part number, it has been some time since I ordered them. They come 4 to a pack.

This combo will scream up top.

I thought I had a picture somewhere. I can hunt one down or retake the shot if you need it.
This is the only shot I found so far.

ld340%20spacer%20carb.jpg
 
Tony, This intake is all ready port matched and the plenum has a notch in it which I think most of them do.

Rob, I think the cam Im going to end up using is a solid around 240/245 @.050" and .550" from Hughes Eng.

I figured I'll be grinding the thing for the TQ and grinding off the Edelbrock script (trying to be sneaky) may as well keep going.
 
I'd leave the Edel. script on and just call it what it is. An out dated intake that has not been produced in a very long time. Since the intake has stopped being produced, Edelbrock came out with the RPM.

Right there you'll get every guy not into MoPars saying to themselves that they'll take you on and win, until they lose to you.
(Of course, everybodys opinion comes in on what you should be running. Those never end. Just tell'em it a on the cheap build and this was cheap. Also you'll take there donations if there opinion is that strong on what you should run. He he he.)

Oh, just call me rumble.
 
Trying to hide what I'm doing is half of the fun. I'm going to leave the Chrysler part number on it though.
 
Would cutting the plenum divider be a beneficial modification if running nitrous? It seems to me it might make the manifold behave a bit more like a single plane which could be advantageous.
 
Thats the idea of doing this mod, kind off. Removing the divider help all cylinders pull from a central location. This mod is like step exhaust in a manor of speaking. (If you get how that works.)
Now that all the cylinders can get at the whole carb, and more plenum area for fuel to atomize better, it will also add to the RPM's ceiling some.

If you were to add a shot of N02, the plate system would be just fine to use.
If your just doing a carb, I would recomend (Engine combo dependent) the experiment of spacers to add more plenum. (Also move the N02 plate up as well.) Doing so without cutting the divider down would make the amount of spacer thickness hard to fit under the hood. And find an effective amount of plenum has space limits on most street bound cars. Stock hooded rides would be impossible.

The old MoPar books recomended a cam of plus .550 lift. Though it is a relation to duration without saying so, a decent lift should be used.
This race mod works well when rules dictate daul plane intake. It is a leagal cheat mod.

F.A.S.T. cars do this to there stock intakes. (Along with max stroking.)
 
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