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      03-16-2015, 03:43 PM   #19
m6beast
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Drives: stock m6
Join Date: Feb 2010
Location: nc

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Great right up and you hit it on the nail on everything you've talked about.

The Dyno numbers do not prove the intakes true potential that's why I vbox and track to show its power potential. The intake has an unconventional design where it is pressurized air as well as higher velocity as you increase mph. After the car has fully adapted it feels like you raised the boost 2-3lbs which in my assumptions proved to be accurate.

Vbox testing on the intake has proven .5 seconds off the 60-130 mph on my bone stock M5 with the intake.

Also a 1/4 mile race against one of my customers cars at the track we ran identical times with same 60ft. He had BMS 3.5 boost, e mid section, turner muffler delete, upgraded OEM intake with charcoal filter delete, BMS filters and RPI scoops. All I had was the intake.

After our race he wanted the intake. He went back to the track after full adaptation and knocked off .4-.5 seconds and gained 4-5 mph in the 1/4 mile.

As for intake temps they would drop 4-5 degrees per pull where the factory would go up 5-6 degrees and eventually heat soak. Also when running the intake if intake temps rose for pushing through its paces it would immediately go back to original intake temps as soon as you let off while cruising a bit. The factory intake would go up more and more and would take for ever to go back to original intake temps.

Also did a test where I sat in a parking lot for 30 minutes and watched intake temps rise from 120-150. As soon as I pulled out of the parking lot and started kicking it intake temps went all the way down to 115 and as soon as I let off went back to normal of 120 plus it was high 90's F that day. Everyone knows any intake sitting in a parking lot will heat soak as well as staying that way for quite sometime and no way for the car to run strong Immediately.

As for rain we drove from SC to OCALA Florida 7-8 hour in pouring rain going 70-80 mph with no issues and all three of us had this setup. The filter material is a stainless steel mesh so rain does not effect it as if it was a Cotten filter.

The prefilter is mostly for those who have the concearn and to give them confidence when driving in the rain. As for sound you can't really hear it from with in the car you have to have your windows down and try to listen. If you have a full exhaust system and catless DP it's even harder to hear. But if you're walking down the road or in a car infront you can definitely hear it.

The pipping diameter was made specifically for the intake to prevent CELs as well as the special made transitions and velocity stacks to give the best flow as well as no turbulence while keeping hoses clamps and attachments to a minimum.

Also it was designed to fit like OEM and not cutting up your car in any way while making everything maintenance accessible so you don't have to remove the intake when servicing.If you decide to sell your car or turn it in an easy swap to OEM with no signs of modification.

The intake took some time to get it right especially how anal I am in fit and finish as well as performance. I don't cut corners and take Pride in every detail.

Here's a comment from one of my customers from Canada

"George,

I finally unpacked your intake last night. Very nice man, I am a fabricator too, but on an industrial scale so I can relate to what you had to go through to bring this to market. I can see lots of precision."

For those who want to see all the data testing on the intake please email me info@mstreetracing.com and I'll send it over. Once again thanks for the support

G

Quote:
Originally Posted by chask View Post
I have a pretty good feeling these dyno hp numbers are most likely a bit off from what is actually seen on the road. It wouldn't surprise me at all if they weren't higher, and perhaps quite a bit when compared to a real world scenario - well, at least on the scale of the change he is talking about (about 20-40 hp).

There ought to be a ram air affect that m6beast alludes to. We have all seen hood scoops and specially designed air inlet ducts on race cars. THey do not go to that trouble for nothing. I have done a lot of engine dyno testing and there are just some things one cannot replicate on the dyno. In this case it is the affect of the air pressure in front of the radiator. With that grill as open as it is, once the car gets above normal street speeds there ought to be quite the pressure buildup in that area where the filters are. As m6beast said, that will make it much easier on the turbos.

Without instrumenting it and testing this on the road to verify things I obviously can't be absolutely sure. But I'd speculate that it would increase the overall air flow into the engine by lowering the intake temperature (a little - if nothing else, unless you are standing still the coolest air around the engine compartment is going to be just in front of the car) and by slightly pressurinzing the air at the compressor inlet (once the car is moving). That ought to mean more air in the combustion chamber, so you can burn more fuel and thus get more hp. I wouldn't be at all surprised if the turbos would spool up a little quicker too, though I have a feeling it's something that would only be once the car was rolling a bit. There is no ram air effect when sitting still so no benefit there. But once you get moving . . . And though my car is still in the break in period (no wide open throttle, not yet ), from what I have seen so far getting this car moving is not too much of a problem.

Since I've not seen the compressor maps for the turbos on the car, I'd be a bit concerned about hitting the surge line, especially if you are trying to run gobs of boost at low RPM. Surge occurs in the low flow range of the compressor. It happens when the velocity of the tips of the compressor wheel reach the speed of sound. Compressor surge is a very bad thing. But if it were happening believe me I really think you would know. It makes a hellacious racket - sort of a chattering sound as the blades go supersonic, then oscillate between supersonic and subsonic speeds. It's kind of like the sound of your tongue fluttering if you hold your jaws and tongue just right then blow, only in this case it is much louder - you hear this nice whine as the compressor wheel spools up then suddenly it's not so smooth and much louder. Depending on how severe it is, it also can also be noticed as a slight hesitation in the vehicle (maybe a slight stuttering sensation), but with as much power as this car has you might not notice that. Back when airplanes were first learning about the speed of sound this 'buffeting' effect knocked planes out of the sky. So this also can tear up a compressor wheel pretty badly (tips can break off - they used to be just cast aluminum), and it's not too good on the bearings either. But I seriously doubt this is happening. I can't imagine that the compressor is sized that close to the surge line or that this mod alone is taking it to it.

The other thing I'd worry about a little is at the other end of engine operation - high RPM, near the shift point. Compressors are usually operating at their least efficiency at maximum boost and maximum RPM. What this translates to is a higher intake temperature. The turbo is merely increasing the air temperature, and in this range of operation (high boost and high air flow) a whole lot. If you start at a lower temperature at the compressor inlet you should see the same reduction at the compressor outlet. With this system grabbing the coldest air available it ought to make a really big difference at that RPM range, especially when you consider how fast the car is moving as a contributing factor to reducing the work the turbo has to do to compress the air. And with the air at the compressor inlet likely at a little higher pressure, it should make the turbo operate more efficiently too - less of a temperature increase. This is why I think the hp numbers are probably a bit misleading. Most likely they are actually higher than what you are seeing on a chassis dyno.

I'd love to see someone put a pressure sensor or two and some temperature sensors in front of the radiator and somewhere after the compressor to see what is really happening here.

There is another possible reason for the increase, and it may be a primary one. It's been a really long time since I have done any of this, but as I recall with an air/fuel ratio of about 12.5 (what you want to be running when the throttle is close to or fully open) it takes about 1-1/3 CFM to make a horsepower. So at 700 hp you are pumping about 933 cfm (cubic feet per minute) through the engine. That's another possible benefit I think I see in this system (or a similar one for that matter). 933 cfm is 15.6 cubic feet per second. When you consider the diameter of the stock inlet piping that air is really honking - calculate the cross sectional area of the tubing and divide it into the flow velocity (make sure you are using the same units - either square feet for cross sectional area or cubic inched for flow velocity). That will tell you the flow velocity. There are all sorts of odd effects on compressible fluid flow (air is considered a compressible fluid) as the flow velocity increases and not many of them are good for making hp. Come to think of it, none that I can think of until the air gets into the combustion chamber. It looks like the tubing MSR is using is a bit bigger than stock. One caveat here - I literally just got my M6 and have hardly looked under the hood so I might be wrong about this. Plus it also looks like they have possibly reduced restrictions in the flow path too - not so many turns and the ones that are there look much smoother. This helps a lot too (a lower flow velocity and less turbulent flow), especially at high RPM. Trying to suck that much air through the intake system causes a vacuum. If you reduce the restriction (make the plumbing bigger) you also reduce the vacuum generated. Since there is no way to replicate the ram air effect I wouldn't be surprised if the dyno gains are mostly from this. But I would not negate the effect of those other factors either, and I would not at all be surprised if there wasn't more there than the chassis dyno showed. Another thing to consider - the lower inlet temperatures and pressures will also help with longevity too.

When you are hunting horsepower, it's usually pretty easy to get enough fuel in the engine. The trick is in getting more air in there, and then out after it's burned (free flowing exhaust system). Anything that improves the air flow is a good idea.

m6beast - I hear you are involved in this somehow. I was professionally involved with turbocharging cars and high performance stuff for about 15 years, 20 if you add in my amateur time (yeah, it's been a while). During that time I saw a lot of this kind of stuff at about all levels - from mild attempts at street beasts to Indy and SCCA champion engines and everything in between. I've got to say this is a really nice looking product. From what I can tell in the pictures and in your test data, as well as from what I have heard locally from people who have used it, it appears to be well thought out and implemented very well too.



I think the worry for me is more with the filter material getting wet. As they are located in that area just behind the grill it is possible that they could get a lot of water on the filter media - if not from rain coming in there (during higher speed motion), having a vehicle just in front of you hitting a good size puddle and flooding the front of your car might do it. Obviously, wet filet media won't pass as much air as a dry one does. But you say there have been no issues with this so far. That's encouraging.



I like the pre-filter idea too - a whole lot. But it is as much for the sound as anything else.



The other thing that bothers me is the noise level. I don't want to get into it but I have a rather unusual health issue that sometimes makes louder sounds more than just unpleasant for me. If I were going to get something like this the goal would be to improve the air flow into the engine, not to make a 'cooler' turbo sound. In fact, I'd prefer it to be as quiet as possible too (yeah, I'm an old fart). Just how much louder is it with this modification? Windows up and windows down, do you get to hear the compressor whine as it spools up and down, or is it just the sucking sound of additional air flow at higher RPMs, or both?

Last edited by m6beast; 03-16-2015 at 04:05 PM..