M1 SP vs Air Gap

Mopar Racers Forum

  1. Moparmal

    Moparmal Banned

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    Has anyone got any data on a comparison between the two intakes?

    I will be running a TQ and 3.89 gears in a smal block stroker - revving to around 6000 rpm.

    It'll see mainly street use.

    Wondering which intake is the better bet - as the stroker will make heaps of torque.
     
  2. mshred

    mshred The Green Manalishi

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    air gap all the way....i have a feeling most others will say the same
     
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    • ColeTrickle74

      ColeTrickle74 Well-Known Member

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      yeah, mshred is right. i posted the same question a few months back. air gap was preferred over the m1 for everything besides pretty much all out race when youll be high in the rpms
       
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      • 340 8BBL

        340 8BBL Well-Known Member

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        ive run both back to back.the air gap made tons more low/mid -range torque,and didnt seem to give up much until about 5800.even then it only gave up very little.
         
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        • BigEdsGarage

          BigEdsGarage Well-Known Member

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          The AirGap will give you better bottom end performance and will certainly still make power over 6000. That combined with the increased torque from the stroker, I would choose the AirGap. The M1 is also taller if that is a concern to you. I've tried both manifolds on my 340 and I like the response of the AirGap better.
           
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          • Moparmal

            Moparmal Banned

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            Thanks for the feedback - just saved me from a $ mistake.

            Height is an issue as well, so I thik the air gap is a more sensible option.

            Currently running an LD40 - reckon Ill notice much in height between it and the Air gap?
             
          • ian

            ian Well-Known Member

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            i think 1 inch taller
             
          • Moparmal

            Moparmal Banned

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            Hi Ian

            Do you mean the air gap is taller than the LD340?
             
          • rumblefish360

            rumblefish360 So close, yet so far away FABO Gold Member

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            I have both LD340 and Air Gap intakes. Would you like me to measure the differences?

            I don't think you'll notice much of a difference between them.
             
          • ian

            ian Well-Known Member

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            yes please, i think air gap is 1 inch taller i may be rong
             
          • 71duster06

            71duster06 Well-Known Member

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            If you have the LD 340 already I would suggest that you dont go with the air-gap. You will notice little or no difference between the two. The air-gap design is more of a sales pitch than a true performance gain. I looked into this issue deeply earlier this year and instead went with the LD340 due to better overall responses. Just an FYI
             
          • Black 69 Dart

            Black 69 Dart Well-Known Member

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            Dyno testing at work we did a comparison, m1 then the air gap made 15hp over the m1 and the indy made 25 more then the m1. Testing was done on a 360, 12.8:1 mech cam, w2 heads and 650 carb. Class engine and that was the carb that needed to be used. 525hp with m1 550hp with indy, just for fun we put a 850 on it and it made 600hp +.

            Trevor
             
          • Sparky

            Sparky Well-Known Member

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            You will need a drop base type air cleaner to insure clearance, works good on mine.
             
          • Locomotion

            Locomotion Well-Known Member

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            ???????????????????????????????????
            The Edelbrock Air Gap dual plane will not bolt on to W-2 heads unless ports and bolt pattern are modified.
             
          • pauly v.100

            pauly v.100 Well-Known Member

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            i have to disagree, i switched from an LD340 to an air gap when my 340 was still alive and the performance increase was dramatic throughout the rpm range. i strongly recommend the rpm air gap.
             
          • rumblefish360

            rumblefish360 So close, yet so far away FABO Gold Member

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            The LD340 is slightly shorter.

            4-5/8 front by 5-9/16 at the rear.
            Compare at http://edelbrock.com/ for specs of the RPM.

            As listed by Edelbrock's site. Manifold height: A-4.75", B-5.8"

            (Port size is .98" x 2.16". and the LD340 is a near perfect match for the Fel-Pro gasket. )
             
          • Moparmal

            Moparmal Banned

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            OK thanks Rumble

            So now Im looking or further LD340 vs AirGap comparisons - Its "One all" at the moment ..............:read2:
             
          • 1968FormulaS340

            1968FormulaS340 Well-Known Member

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            The air gap is better but I don't think I would rush out and buy one just to replace an LD340.

            It will be far from a life altering change. It's like twin sisters.... Let's say both are super hot..... but one is say... 5'-8" and 124 pounds and the other is 5'-8" and 127 pounds... Both will get the job done but I wouldn't make much of an effort to get one over the other.
             
          • Moparmal

            Moparmal Banned

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            Now THAT explanation is gold!! LOL!!
             
          • Hysteric

            Hysteric Well-Known Member

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            I know of 1 racer here in OZ who went from an Airgap back to a RPM and lost only a tenth!

            Mal. If i were you and you have the LD340 id look to put an open 1 inch spacer and maybe paint the bottom of the manifold with some heat proof paint.

            Hysteric
             
          • a-bodytom

            a-bodytom Well-Known Member

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            rpm air gap is what i would use good responce ,tq, and good looks i got one and works nicely on magnum heads
             
          • Moparmal

            Moparmal Banned

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            I may not get a 1" spacer under there - but I did find blocking the heat crossover made a suprising difference.

            Im not desperate to swap it out - so just trying to find out if anyone has compared the two?
             
          • rumblefish360

            rumblefish360 So close, yet so far away FABO Gold Member

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            The 2 intakes are the same as you described with the only difference being the seprated runners and lack of heat cross over on the RPM. All engines like a cool ense clean air fuel charge and if I was running the street in the chilly weather, I'll run an intake with a heat cross over. It's worth the quicker warm up time and reduction in plug fouling over the few HP it's worth.

            MAL, if I didn't have ethier and the engine build was a "Hot Rod-ish" in style like/type build without cold driving, the airgap would be the choice.

            Also, since this is a 400+ stroker, I would guess this is in the toy car rather than the everyday driver. You'll just have to say to yourself if the expense of the Air-Gap is worth the extra power/wow factor etc.......

            I just picked up a LD340 for my 360 build for my daily driver. A 3800+ lbs. '79 Dodge Magnum. It was alot cheaper than a new RPM and it's a old school period correct part.
             
          • HotLines

            HotLines Realist - Free Thinker

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            Just out of curiousity can you tell me where you've gotten all those intake manifolds to fit the W2 heads or are they an econo look alike with the same bolt patterns?
             
          • moper

            moper FABO Gold Member FABO Gold Member

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            The LD 340 is the best in terms of street power from the 70s and 80s. I think the AG will outpower it pretty much all the way accross the board now. It's not much, but I'd bet it's noticable. There is nothing different betweeen the AG and RPM so either would be fine IMO.
             
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