Edelbrock LD4B - what's the operating range?

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halfafish

halfafish

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I've looked all over, even Mr. Google can't answer this question. Does anyone know what the suggested RPM operating range is for this manifold?
 
Around 1500 to5500 but that will depend on engine size ,I had one one a 318 it pulled hard to 7000rpm
 
You probably need an old speed catalog to find what it was advertised. Better than a Performer, might be able to do the old Super Stock trick of milling the divider to 3/8 from the floor and gasket match. I'll see if it is listed in the old one I have.
 
It's all dependent on camshaft selection.

Example:
Stock 340 cam
Operating Range > 0 to 5000 rpm.

☆☆☆☆☆
 
As said, it depends what you want to use it on. On a small head 273/318 it will be strong with a 6500 or so shift point if it's cammed right. Just incase you want to go higher with a small engine, the much hated "Torker 340" with it's medium port size will add another 1k or so. :)
 
I’d call that an idle to 6,000 intake. But of course, like said above, a larger camshaft and ported head and etc….. you get the idea…
I really don’t see a problem to 6500.

I do wonder what the old catalogs listed it as. Hummmm
I had one on a 318, small cam, 216@050. I’d run it to 5500. That’s all that the llittle cam really had in it inside the 318. Peppy lil’bastard it was, for what it was.
 
I had one on a .060 over 360, with the Mopar .484 cam, the heads were stock 360 heads with mild porting and good valve job. It pulled well up to about 6800 RPM.
 
Completely combo dependent. It would pull to 7500 under the right circumstances. I agree a good general guess is probably 1200-5500 "or so".
 
I had one on a 10.5 to 1 360 with a 230/238 @.050, .515/.535 on a 108 cam. 780 carb and 1 5/8 headers. This was in a 1/2 ton mud race truck. Shifted at 6500, ran it out 6800.
 
Carried well to mid 6000s on @CPDave 's 318
who has the fastest 318 ?!!!

On a 340 in Hot Rod magazine's Mopar Manipulatin' part II
www.forabodiesonly.com

Mopar Manipulatin’ , HRM August ‘69

www.forabodiesonly.com www.forabodiesonly.com
Looks to me like in that testthe torque peak is 6750, and was equal in power to the LD340 at 6000 rpm.
But not so strong below and above that rpm on the 340 with cam etc.
Maybe the change in intake should have been tested with different jets, but that was, maybe steill is, typical of magazine tests
 
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Very hard to give an exact rpm number because the peak airflow of any intake manifold is going to be dependant on a few factors, one of them being the cubic inches it is feeding.

The LD-4B is listed as having a 1500-5500 rpm range in my 1979 catalog. Edel says the performance will be enhanced throughout this rpm range, but is not limited by it.
 
Thanks for the info guys. I'm considering this intake for my 72 Coronet wagon. It will be set up as a cruiser so light-to-light performance isn't on my radar screen. Right now the car is a dead stock 318 2-barrel. I'm not distressed with the level of get-up-and-go it has currently - I could live with the present arrangement if I had to.

I'm guessing the car with me in it is somewhere around 4000 lbs. I believe the mileage is still the first time around at ~58K or so. I need to do another compression check but if it's good I'm fine with leaving the bottom end stock and working from there. If the bottom end needs help I'll have to evaluate the situation at that time to see about just boring over .030 or so, or going to a 390 stroker. I can kick that car far down the road for now however. The car runs great. :)

I doubt this car will ever see the far side of 4500-5000 RPM and likely a lot less. My plan is to pick up a set of loaded Speedmaster heads on Black Friday, add a smallish SFT cam (not much more than 224* at .050 and about .470 lift or so), a 4-barrel intake (carb likely a Street Demon 625 or a TQ 6139s). I'd prefer to keep exhaust manifolds for the factory look (maybe 340 HP versions?) but I'm not dead set against some long-tube headers. The end goal is whatever I can squeeze out of the car for mileage with improved performance as icing on the cake. Right now the car has 2.94 gears but I'm giving serious consideration to going to 3.91's with a 4-speed lockup OD trans. That combo will get me something like 2.8x gears on the highway and will move out quite a bit better.

Back to the intake question, with the above I'm looking at either an Edelbrock Performer (stated RPM range is idle-5K or so) or the LD4B. What says the forum gurus?
 
A Performer would do you just fine. At half the cost. Or for even cheaper, source an iron TQ intake. Works just as good or better than the Performer. Just heavier....
 
for that particular application a performer, the LD or a stock TQ intake are all going to be comparable. i'd probably push toward headers to pick up a little more low end and midrange torque as well as cost considerations, but you wouldn't be losing much at all with 340 manifolds.

i like that combo and the addition of a OD lockup with some gears out back should really make it shine all around.
 
Don't know if your wagon has AC - as I recall the arrangement of runners (which are high and which are low) keep you from reinstalling the AC with the LD-4B. This is not true for the Performer, it all fits fine. It is amazing what a difference a manifold, 4bbl and decent dual exhaust make on a 318! Yes there is a Performer intake and an Eddie AFB hiding under there...

IMG_1008.JPG
 
str12-340 said:
Don't know if your wagon has AC - as I recall the arrangement of runners (which are high and which are low) keep you from reinstalling the AC with the LD-4B. This is not true for the Performer, it all fits fine. It is amazing what a difference a manifold, 4bbl and decent dual exhaust make on a 318! Yes there is a Performer intake and an Eddie AFB hiding under there...

View attachment 1716150911
Click to expand...
I have no air on the wagon and no plans to add it. We share the same weather so I'll just gut it out on hot days with my 5/60 vent system. :rolleyes:
 
Then, I myself would use a cam of no larger than 216@050.
(Mileage considerations in mind.)
Agreed on the Performer or factory iron intake.
Headers open up power and torque everywhere. Especially down low in the rpm range.
 
Kinda smaller than a stock 340 one. We always used them like a performer and worked from idle to what cam did. But only ran stock size 340 cams with them.
Good intake on 318, 340 and very mild, and A/C
 
toolmanmike said:
They really don't wind much higher than any other small block. Redline on the 4 barrel engine was 5200 If I remember correctly.
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And that is with a cam with intake lift of .415 and duration of 202.8 @.050 and exhaust lift of .425 and duration of 207 @ .050.
 
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