Air Gap vs. M1 Single Plane For Stroker
- Thread starter Mean416
- Start date
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If I was to guess the air gap will be better in the streets and even maybe at the track, single plane might help it hook up easier in the street with the loss of down low torque. I'd try the M1 1st then air gap since you'll probably like the air gap better in the street.
I am probably the least experienced guy to chime in here but it seems obvious to me.
M1 = 3000-8000 RPM range
Air Gap = idle to 6000 RPM
The M1 only has the advantage at 6000+. If this were a mostly strip and not so much a street car then I would say go for the single plane but just how damn fast are you wanting to get to the donut shop? Is it at the big end of 1/4 mile? That's where the M1 would shine but the AG starts working from takeoff. How much are you going to be in the 6000-8000 RPM range on your drive to work to take advantage of all that power the M1 gives you.
4200 stall convertor for the street? I'm still learning about convertors so I would be interested to hear about how it drives.
I have a Duster roller that I want to turn into a street legal drag car in a few years. Not much street usage but capable of going to the burger joint. It would kind of be the opposite of your usage but pretty much same set up that you have. 4.10 S60, 408", Auto/ high stall, Cal Tracs .... For that application I would do the M1.
Sounds like we have the same goal, I just will have less opportunities to go to the strip!
:'(
X’3. Pic’s below, 2 weeks old. Starting off with a dual plane 340 @ 10.5-1. Proceeding with the lightening program first and hard. When it grows up, it’ll loose the metal up front, windshield wipers, headlights and horn, etc… for now they stay. Or until the goal is met.
The Edelbrock RPM-AG & 750 are great to start with. Cam is a mellow HFT w/small headers. Generally speaking, I don’t think it’ll be fast, but that’s also a point of view, just not mine at the moment. There is “A LOT!” yet to do. Hopefully a fun journey.
Come on down to Lakeside and I’ll give you a ride in the Dart. It has a 410 with an Airgap, 4100 stall and 4:10 gears.
Now there’s an offer I couldn’t refuse!
Was that a solid recommendation for n air gap then?
I like it, however haven’t ran anything different on the motor.
K.O. SWINGER
Meeting in the alley since 1976
I don't think you'll see any noticeable difference one will be a little stronger down low a little maybe, and one will have a small advantage on top equals personal preference. Both are very good manifolds and due to the strong torque of a 4 16 you're not going to lose anything on the bottom end to an air gap. the heads will limit top end so you're not going to really gain anything with an m1. You choose.
The head issue as described above is very true.
This is also how I feel about the intake difference.
And not to beat a horse, I feel the cam leans towards the AG.
In the MP top section, they recommend a 6 pack in the 11 second bracket tip section. AKA, a dual plane. The cam is the Purple 296. 252* (or more) degrees @.050. This is where other members have found there switch from the AG to the single plane almost right, not quite.
The car has to be seriously light to take advantage of the single plane.
This is also how I feel about the intake difference.
And not to beat a horse, I feel the cam leans towards the AG.
In the MP top section, they recommend a 6 pack in the 11 second bracket tip section. AKA, a dual plane. The cam is the Purple 296. 252* (or more) degrees @.050. This is where other members have found there switch from the AG to the single plane almost right, not quite.
The car has to be seriously light to take advantage of the single plane.
K.O. SWINGER
Meeting in the alley since 1976
Not to argue the point but if I recall and I no longer have my MP Bible s***! Those recommendations were for 340 360 cubic inch motor I feel when you throw a 4 inch arm in the mix unless you're dealing with a heavy pig of a car there's no real advantage/ need for a dual plane manifold ? imo.
Ate you saying the torque down low in the curve pulls the car through the low rpm range and when it gets on step it takes advantage of that single plane? I can see that.
If the car was low on power (smaller cam, shorter stock stroke) it would need the dual plane?
Just trying to learn.
K.O. SWINGER
Meeting in the alley since 1976
Yes basically that is my feeling. When you add a 4-inch stroke to a motor you instantly add over a hundred foot pounds of torque all of a sudden six or seven pounds of torque that is gained by a dual plane seems not that important. But there's no arguing that a RPM air gap is a top notch manifold. I just feel with that much torque on hand that I would possibly move away from a dual plane and take advantage of the throttle response and fuel distribution of a m1 single plane.I don't think it would be worth changing from one to the other with your particular build I think both if tuned properly would be within a tenth of each other. I ran an m1 single plane for many years and it is a fine manifold! But never on a 416. But I sure wouldn't hesitate.
Send me a PM. I am going to have to take off to Mammoth Lakes for a couple of months to be a driver for a fire engine up there that lost it's driver. Going to be leaving in a week and have leave scheduled till then.
Would love to go for a rip.
I agree to a point. Where the point is, I’m not sure.
I disagree with what you say afterwards on the amount of instant torque produced by adding a 4 inch arm. Mostly because it is build dependent.
In your inbox!
I have been watching a lot of Dyno testing of different combinations lately and there's a guy, his name is Richard Holdener. Check him out on YouTube. Very sharp guy and makes some very interesting observations and explanations of things. He has done a ton of tests comparing single to dual plane, shirt runner and long runner intakes and it almost always leans toward the long runner or dual planes, anywhere under 6k. Not just small displacement street motors eithi. His point on this is regardless of displacement, boost or no boost, the intakes generally are more rpm dependant than anything else. And he backs this up with Dyno pulls. And we're not talking 5 ft lbs torque. It's often like 30-50 ft lbs for large stretches of the power curve. That's a big reason why I've been seriously pondering this in the first place.
I doubt the M1 will give you any usable gain over the Air Gap especially in the streets and after if it seems you need less bottom and more top you could always try the M1 , if I was to only try one it would be the air gap even for the track.
448Scamp
Running Free
YouTube videos are the new car magazine. You just can’t swap intake manifolds and look at the results. Everything is affected by everything else. If you don’t take that into account you get bad data. The other thing to think about is how a dyno works. Like a flow bench or a Vice grip it has limitations. You have to know what those are and deal with them. Different dyno types produce results. An eddy current dyno won’t tell you the same things a water brake dyno will, and it will have different limitations as well. Throw in an inertia dyno and you have another set of variables and limitations to cope with. What I’m saying is one intake manifold may look really good on say a water brake dyno and look like crap on an eddy current dyno, but the track results may say the eddy current dyno numbers were correct. Or maybe not. I guess the point I’m making is dyno results are not the final say in what works and what doesn’t. It’s a tool with benefits and limitations and you have to understand that when using data from a dyno to make a decision on what parts to use.
As someone who has operated a dyno I totally get it.
I'm pretty sure this guy is a Dyno operator for westech, he's a legit dude and I recommend checking him out.
Yeah there's a bunch of BS on YouTube but there's a bunch of random nonsense in forums, this being no exception. You gotta take the info available and filter out the BS as best as you can and go from there.
I'm pretty sure this guy is a Dyno operator for westech, he's a legit dude and I recommend checking him out.
Yeah there's a bunch of BS on YouTube but there's a bunch of random nonsense in forums, this being no exception. You gotta take the info available and filter out the BS as best as you can and go from there.
TT5.9mag
Two atmospheres are better than one
Richard is a smart and honest dude. He rents dyno time from westech and does his videos there. They are local to me and I have had engines dynod there so I’m quite familiar. Good shop for sure.
Echoing some of the above, what shows on a dyno doesn’t always translate at the real world track.
I absolutely love that your going to try both intakes.
This way, no matter what the track or dyno says, you will use what you like and that right there is the bottom line.
I look forward to your results, opinion & reasoning.
I’m actually excited to read this thread and the future results.
448Scamp
Running Free
I didn’t mean to infer anyone making stuff up or isn’t legit in their methods and such. My point was the limits of the test machines we use. It’s the nature of the tool. Anything that comes out of Westech is worth looking at. Just the years of accumulated knowledge is incredible.
TT5.9mag
Two atmospheres are better than one
The real test will be when YOU drive the car, how YOU drive it, on the street with both intakes. With as little track time as you say it’s gonna get and as much street time, I’m guessing the RPM is the one you’ll like the best. Regardless of which on is actually faster.
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