Mopar 340 Intake Question

[squirrel]

Re: Mopar 340 Intake Question

I have lots of experience with 340's.

Ditch that performer and stick on a stock iron 68-70 340 intake - you will make more power.

heh....I love reading things like this....

[Freiburger]

Re: Mopar 340 Intake Question

I have lots of experience with 340's.

Ditch that performer and stick on a stock iron 68-70 340 intake - you will make more power.

heh....I love reading things like this....

I'd like to see the test. It could very likely be true (Performers are often similar to stock iron four-barrel castings, though the Mopar intake is closer to 318 runner sizes). But when I did that same back-to-back test, the power difference wasn't enough to make up for the weight of the cast-iron intake. Like 2-5 numbers if I recall. And the LD340 was better, with the Air Gap being best. Wish I could find my data easily.

[squirrel]

Re: Mopar 340 Intake Question

I wouldn't be surprised if the car were a tad faster with the aluminum intake, but the cool factor of having a 40 your old lump of iron when everyone knows you need an aftermarket intake would be worth the sacrifice.

My favorite stock intake is the 50 lb cast iron high rise Qjet manifold on the early 396s.

[Freiburger]

Re: Mopar 340 Intake Question

I wouldn't be surprised if the car were a tad faster with the aluminum intake, but the cool factor of having a 40 your old lump of iron when everyone knows you need an aftermarket intake would be worth the sacrifice.

My favorite stock intake is the 50 lb cast iron high rise Qjet manifold on the early 396s.

Going fast with stock junk is always cool.

[Freiburger]

Re: Mopar 340 Intake Question

Also FYI, I personally would not put hypereutectic pistons in anything. If I had to, I'd use the Speed-Pro ones.

[squirrel]

Re: Mopar 340 Intake Question

ditto on the hypereutectics....normal cast pistons are quiet, and you might as well go for real forged pistons if the engine needs something better.

[HillbillySailor]

Re: Mopar 340 Intake Question

Nice! Thanks for all the good info everybody. If I get a Mopar, I'll do this to a 360. So if my friend won't take advantage of all this, I will.

[mopower58]

Re: Mopar 340 Intake Question

We have the engine built for my son's '71 Duster. It is a .020 360,with edelbrock heads, 10.5 compression, air gap intake, and a .509 mopar cam. Should make around 400 hp on pump gas.

[HillbillySailor]

Re: Mopar 340 Intake Question

We have the engine built for my son's '71 Duster. It is a .020 360,with edelbrock heads, 10.5 compression, air gap intake, and a .509 mopar cam. Should make around 400 hp on pump gas.

You HAVE to take this car to the strip when you're done! I want to see what the lttle A-body can do with that kind of motivation! If I had that kind of motivation, I'm sure I'd get to see Officer Friendly alot...

[mopower58]

Re: Mopar 340 Intake Question

Oh trust me, he is dying to get this thing together. I will keep you posted.

[RacerRick]

Re: Mopar 340 Intake Question

I have lots of experience with 340's.

Ditch that performer and stick on a stock iron 68-70 340 intake - you will make more power.

heh....I love reading things like this....

I'd like to see the test. It could very likely be true (Performers are often similar to stock iron four-barrel castings, though the Mopar intake is closer to 318 runner sizes). But when I did that same back-to-back test, the power difference wasn't enough to make up for the weight of the cast-iron intake. Like 2-5 numbers if I recall. And the LD340 was better, with the Air Gap being best. Wish I could find my data easily.

The performer is designed for the 318 size intake ports and has corrospondingly sized runners. Its also shorter than the factory 340 intake and has less plenum volume. It seems more designed toward easily putting a 4brl on the 318 than a performance upgrade to the early 340/360's. I think the performer is more along the lines of the old SP2P's.

The old LD340 is a good intake and is very similar to the old non smog 340 intake. The Performer RPM seems to be the first really updated design in a long time and works well. The air gap wasn't out, but I would have like to check that one out.

On my old 340 I tested several intakes. Offy 360, Eddie Performer, Performer RPM, MP M1 single plane, stock non smog thermoquad, and early 340. I used both Edelbrock and holley carbs on the square bores and the Thermoquad on the thermoquad intake.

The car et'd the best and had the best MPH with the MP M1, at 112mph. The Performer RPM was second in line at 110mph, but much nicer to drive around as it made more bottem end power. Behind it was the stock intakes - with the thermoquad running 109mph, and the 340 intake running a half mph slower (slightly smaller carb is probably the reason - 750 holley vs the 800cfm thermoquad). The performer was 107mph, and the stock Offy sucked at 104 mph and killed power everywhere. The car hated the Offy.

[Freiburger]

Re: Mopar 340 Intake Question

That's good stuff, thanks.

[HillbillySailor]

Re: Mopar 340 Intake Question

Outstanding info. I found a few LD340 intakes on Ebay. Those damn things aren't cheap. but if you want to play, you have to pay.

[ksj1]

Re: Mopar 340 Intake Question

If I would have kept all the LD340s and DP4d's from years back I could retire. ;D I just bought a DP4b off E-bay.Dang near what I paid for one new.Oh well.Live and learn. maybe

[kick_the_reverb]

Re: Mopar 340 Intake Question

Hillbilly Sailor,
You mentioned the Edelbrock "340" heads - notice that these are "problem solver" heads for someone who wants to drop the heads on a short block that has the stock high compression positive deck pistons. If you're starting with new pistons, try to go with zero-deck flat tops and the "regular" Edelbrock heads. With a .039" head gasket you'll have perfect quench, which will help with detonation resistance.

Good luck,
Ran