LD340 or RPM Air Gap

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Shane

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Ok, so I now have my car running good (68 Barracuda), and I have this question in the back of my head all the time, so I figure I would ask it here and then it wont have to be in my head anymore...

A few months back I purchased a 340 that is now in the car with most of the major kinks worked out..

The motor is a 69 340 block and X heads, it was all a part and I checked it out..and it was put together for me, since I am new to this and that would have been a little out of my league (..maybe next time)

It came with a mopar purple cam(not sure of the lift numbers), windage trays, a holley 600 double pumper, and an LD340. I had to use my own bellhousing, starter and alternator that was in the car.

My big question is , I understand that the LD340 was a real good intake when it came out, but now adays we supposedly have higher technology(joke) (not that good of one), and I am wondering if I would see any/Big performance improvements if I switched over to the RPM Air Gap??

oh, I also have electronic ignition and a msd box...if that makes a differences....


any opinions/thoughts to shut the little voice in my head up would be appreciated...

Shane
 
A very good intake for the money is the Weiand Stealth. I messed around with a few different intakes on my combo and the Stealth put out the best numbers.
 
i had almost the same setup on my 340 (a little bigger cam)
i changed from the LD340 to rpm air gap just like what you're thinking of doing. the difference is truly dramatic. if you are considering the swap, then do it, you won't be disappointed.
 
A recent test of several Mopar intakes by a car magazine showed the LD340 to still be a very good performer, however the RPM Air Gap had better horsepower and torque numbers across the whole range.

Now the question is,,,
How well would your 340 respond to the intake swap? Most likely with the parts (cam, carb and heads) that your 340 has, the increase would be worth the cost and effort. An RPM Air Gap is a very nice performing intake.
 
Depends. I've seen engine not respond well to the Air Gap when a LD340 was swapped. The difference was so negligible, that it was a complete waste of money.

I know Barton and a few other don't feel it's a cost effective change in some cases. Everyone is a bit different. Not knowing which camshaft you have, would definitely deter me from making any suggestion. If it's the smaller grinds, no chance I would swap it. If it's a .508-509, then possibly.

The LD is a VERY capable manifold.
 
thanks for the replies....what everyone was saying was what I was thinking....

is there any way to find out exactly what purple cam it is?

i am thinking(pretty sure) its a bigger lift cam, it takes some time to run right when shes cold, it sounds Wild when idling, and talking to people in my area that know the old cars, and they seem to think its a large lift cam....
 
The best thing about a MoPar cam is there long duration vs. the advertised duration and 110 centerline (Or less0 For that big chop sound, even when there small.

The intake swap is a small gain not worth the money unless you have a set up willing to take advantage of the newer intake. There close in performance.

I did the MoPar mod's to the LD-340. I also have both intakes and working on a 360 to test and have fun with them.

http://www.forabodiesonly.com/mopar/attachment.php?attachmentid=10166&d=1173218221

This thread; http://www.forabodiesonly.com/mopar/showthread.php?t=24073
 
If you have an LD340 now I wouldnt spend the extra for the little gain.
 
Hey Adam, I went thread hunting and you photo's of your LD-340 are no longer there.
 
IM000979.jpg


IM000978.jpg


IM001001.jpg
 
I just swapped a torker 2 to an air gap.Not to much change.I,m gonna try 1 inch spacer with it now.just 2 cents
 
pettybludart said:
I just swapped a torker 2 to an air gap.Not to much change.I,m gonna try 1 inch spacer with it now.just 2 cents
Click to expand...

Shane said:
Ok, so I now have my car running good (68 Barracuda), and I have this question in the back of my head all the time, so I figure I would ask it here and then it wont have to be in my head anymore...

A few months back I purchased a 340 that is now in the car with most of the major kinks worked out..

The motor is a 69 340 block and X heads, it was all a part and I checked it out..and it was put together for me, since I am new to this and that would have been a little out of my league (..maybe next time)

It came with a mopar purple cam(not sure of the lift numbers), windage trays, a holley 600 double pumper, and an LD340. I had to use my own bellhousing, starter and alternator that was in the car.

My big question is , I understand that the LD340 was a real good intake when it came out, but now adays we supposedly have higher technology(joke) (not that good of one), and I am wondering if I would see any/Big performance improvements if I switched over to the RPM Air Gap??

oh, I also have electronic ignition and a msd box...if that makes a differences....


any opinions/thoughts to shut the little voice in my head up would be appreciated...

Shane
Click to expand...

Shane:

The Air Gap will give you cooler fuel delivery. Too many engine combos out there to really justify the swap.

I would keep the LD, especially with the Holley.
 
thanks for the input...for the amount of money it doesnt seem that its worth it right now...

since I got the topic going, Do you guys think that 600 holley is to small for the motor?
 
Shane said:
thanks for the input...for the amount of money it doesnt seem that its worth it right now...

since I got the topic going, Do you guys think that 600 holley is to small for the motor?
Click to expand...
Shane

I think your in the ball park.If your not happy with its street manners, then you could jet it up a couple of sizes. Except for the cam, you are basically stock, right?

A 750 would be too much.

Unless you dyno and A/F test the engine you really won't know.

If you can light 'em up, just leave it.

Look at all the money I saved you!

DSCN1219 (Small).JPG
 
Oh they light up good!

I am trying to take it easy until I wield in my subframe connectors....last major thing I gotta do this year...

ahahhah yea you did, I'll have to buy the coffee and maybe even a donut when we meet up...ahaha
 
Most of the cost of the newer manifold. I have $100 for the LD340 if it's in good shape and has the original factory part number next to the carb.
I'm looking to restore my 69 to the early 70's spec's which their is no demand for.
 
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