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2004 Acura TL, 1999 GMC Yukon
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Discussion Starter #1
So I was discussing cars with my nephew Aron (who is older than me) this Thanksgiving, and the talk turned to intake manifolds. He has a weird fetish about them.

He also has lots of experience in aerospace composites, an understanding of the physics of how air moves through the engine, and a understanding of how to calculate the correct plenum size, port size, port angle, yadda, yadda, yadda. I described the difficulty in getting big power from the 117, and my suspicion that the intake path is the main reason for the difficulty. He is eager to develop and build a few for us. He is also a doer, not a talker. He lives in Tehachapi, CA.

I wanted to gauge interest. I told him that there were probably 3 or so of us that would be seriously interested and willing to pony up with some money. Of course I offered my car as the lab rat. He is pretty stuck on doing them in carbon fiber, saying that it transfers heat at a rate 300times less than that of aluminum. I want to convert my car to FI as soon as I get a chance, but I'm not going to do it on the factory intake setup.

What do you guys think?
 

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Two '87 570SECs, one '87 560SEL
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I've heard that the exhaust ports are very close to a 5.0 Mustang V8 so folks have been trying to modify Mustang exhaust headers for the M117. My GM LS6 uses a plastic intake manifold that flows *very* well and has the injector ports in it.

Before you put too much effort into a custom fabricated intake manifold, maybe a look into M117 intake port placement and the potential for minor mods to get a US V8 manifold functional might be easier.
 

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1989 500SEC
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perhaps some kind of adapter plate to allow use of a more popular V8 intake manifold? I have the intake manifold off my spare M116 at the moment, im going to get the ports measured at work on the co-ordiante measuring machine so I can design my own manifolds so I can fit bike throttle bodies. I have already had the exhaust manifold measured if any one wants the CAD data to make their own, its just the location of the exhaust ports, bolt holes and the downpipe flange, so quite useful if you want to make SS headers which are a straight swap.
 

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1966 200 Diesel; 1985 500 SEL (wrecked); 1991 420 SEL; 1979 280E (Home Market); 1993 190E 2.6
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I have often wondered about fabbing a better intake. I know lots of folks do tri-Y's and other exhaust mods, but what about the intake? It seems to me you could bolt a culvert on for an exhaust, but if the intake is too restrictive whats the point. (exageration of course but you get the point I hope) Carbon fiber does, at least initially, seem to be a good choice of material.

Keep me posted pls.

-Wolf
 

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1983 500 SEC Lorinser 1971 280se w108
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bike throttle bodies
Surely to small
How about two sets of quad TBs off a 90s toyota levin/trueno 4age 20 valve
Im pretty sure from memory that the Injector ports are in the manifold so you can ditch em and still use the ones in the heads of the M117
 

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Depends on the day!
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ITB's would be spectacular, but as Joe says, quads would do great..! the intake is a large limiting factor and yes, the path to Real power would be in a proper intake and appropriately sized airbox!
 

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1966 200 Diesel; 1985 500 SEL (wrecked); 1991 420 SEL; 1979 280E (Home Market); 1993 190E 2.6
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ITB's would be spectacular, but as Joe says, quads would do great..! the intake is a large limiting factor and yes, the path to Real power would be in a proper intake and appropriately sized airbox!
Yeh, definately a proper airbox too, excellent point. I don't think it would be that hard, but the fluid mechanics have my head hurting already. I will have to think on it some more when I start tearing down my .963. We can talk about cams sometime when I get that far I hope.

-Wolf
 

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I would want to stare at it a bit with the stock intake off, take some measurements, think for awhile on all this, crunch some numbers, then rinse and repeat.

-Wolf
 

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Well, of course, the way around this is to force more air through it...I've toyed with the idea of putting an Eaton supercharger on top of a 380 (M116). The right way to do this is to put a box under the supercharger, and route short runners to the head intake ports, and for several thousand dollars, there are people who will craft these from dead scratch out of welded aluminum plate and tubing. I was thinking of putting a mounting plate on top of the present upper manifold, and forcing the air through the lower and back to the upper. Not all that efficient, but possibly doable with my means. The Eaton outlet magically aligns well with the lower throttle body mount/opening (I'd be using the GM3800/Hitachi throttle body before the supercharger, and this TB has all the modern sensors and goodies on it). My goals are not crazy performance, just good performance from a 380 (on par with a stock 560) and good gas mileage. I'll never get crazy levels of boost out of it because there won't be an intercooler, and boost is limited anyway by how big of a pulley I can weld to the crank pulley and how small of a pulley I can get for the supercharger.

There is a place around here that designs and manufactures plastic intake manifolds (for Toyota's, among others, apparently). I wonder what THAT tooling costs. On the other hand, with modern CAD and "santa claus" machines that go from computer to prototypes to molds, who knows?

I've examined this type of plastic manifold on several types of cars, and it's amazing that these things are as strong as they are and apparently they last. That guy in the movie "The Graduate" was right!!!
 

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Discussion Starter #11
I would want to stare at it a bit with the stock intake off, take some measurements, think for awhile on all this, crunch some numbers, then rinse and repeat.

-Wolf
My nephew definitely appreciates the need for PROPERLY sized and placed plenum and runners. I'm excited to have him involved in something I had planned on doing mostly myself.

So, how many would realistically be willing to pony up for a proven (on my car) intake at a reasonable cost? I'm really only expecting 3 at the most, but we'll see?
 

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1983 500 SEC Lorinser 1971 280se w108
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You would probly get more people to pony up if you supplied the manifold along with a good proven base map to go along with the EFI conversion that will be needed to fit it
If i could buy an ECU and fancy Intake combo at a reasonable price in my neigbourhood my morgage payments would be in danger LOL
 

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Tribute 500SEC AMG Widebody
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a nice plug n play, try n tested efi kit would serve the M117 community well.
 

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The thing is that once you have set a good base map on something like megasquirt it costs nothing to share it
Obviously anything shared would need to be fine tuned to suit individual installs specs
ie Injector sizes etc
I still have my mostly compleated set up sitting in the garage but I simply cannot be without my SEC at the present time so who knows when I will do anything with it :(
But If I do ever succesfully get it up and running I will certainly make my maps available to all free of charge...
 

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My nephew definitely appreciates the need for PROPERLY sized and placed plenum and runners. I'm excited to have him involved in something I had planned on doing mostly myself.

So, how many would realistically be willing to pony up for a proven (on my car) intake at a reasonable cost? I'm really only expecting 3 at the most, but we'll see?
Well I guess for me that would all depend on how it ends up working out for you, what EFI solution you come up with, and if we both have a similar definition of what 'reasonable' is.

I am still very interested in what you may come up with.

-Wolf
 

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The problem with trying to use a US intake manifold are the oddly spaced intake ports. MB does use a much better intake manifold in the newer engines, the model numbers escape me right now.
 

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1989 560SEC
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perhaps some kind of adapter plate to allow use of a more popular V8 intake manifold? I have the intake manifold off my spare M116 at the moment, im going to get the ports measured at work on the co-ordiante measuring machine so I can design my own manifolds so I can fit bike throttle bodies. I have already had the exhaust manifold measured if any one wants the CAD data to make their own, its just the location of the exhaust ports, bolt holes and the downpipe flange, so quite useful if you want to make SS headers which are a straight swap.

Khimani_mohiki,

If your offering, I would like a copy of the CAD file i.e. iges, stl or stp format works for me. We use Solidworks for CAD and PCDMIS for CMM inspection. I would love to have it just for reference.

Thanks,
Mike
 

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sounds interesting... could you email me the CAD files too please? [email protected]

Also, is the injector spacing between the M116 and M117 the same? Intake port spacing? I have a dead M116 that I am fabbing up an eaton m90 manifold, efi fuel rails and the biz. I'd be perfect if this fit the M117 too.

My intial play suggests that Toyota 7MGTE injectors (2.9ohm, 440cc/min) fit and seal quite well. Plus they are cheap with plenty of aftermarket options for higher flow rates...

Will keep you all posted on my learnings.
 

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This is very interesting and I am willing to be part of it. But we should first establish a baseline to know if effectively the current intake manifold is a restriction, and if yes is it a problem with the runners, the plenum or the throttle body. For this we would need to measure vacuum in diferent places at WOT and 7000 rpm or so. One place should be after the runner before the intake port. The idle circuit could give a good plugging point. Another place should be the plenum. Any vacuum port directly in the plenum will do.

Depending on values one would know if and where there is a restriction and how best to address it. Ideally these measurements should be done on an engine equipped with more aggressive camshafts.

It has to be noted that more air will benefit the engine at higher rpm only as obviously air needs at lower rpm ranges are met.

It is also good to note that AMG did not go with redesigned intakes, when it did on earlier engines. It even did not increase the size of the TBs.

Any AMG owner interested in running a series of vacuum measurements?
 

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This is very interesting and I am willing to be part of it. But we should first establish a baseline to know if effectively the current intake manifold is a restriction, and if yes is it a problem with the runners, the plenum or the throttle body. For this we would need to measure vacuum in diferent places at WOT and 7000 rpm or so. One place should be after the runner before the intake port. The idle circuit could give a good plugging point. Another place should be the plenum. Any vacuum port directly in the plenum will do.

Depending on values one would know if and where there is a restriction and how best to address it. Ideally these measurements should be done on an engine equipped with more aggressive camshafts.

It has to be noted that more air will benefit the engine at higher rpm only as obviously air needs at lower rpm ranges are met.

It is also good to note that AMG did not go with redesigned intakes, when it did on earlier engines. It even did not increase the size of the TBs.

Any AMG owner interested in running a series of vacuum measurements?
Well said. +1
 
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