prototype Eaton M90S based S/C system

[Mark911]

400hp prototype Eaton based S/C system

This is a picture of my prototype Eaton M90S based S/C system. This is an AEM EMS controlled air-to-water intercooled system with a highly modified stock intake manifold and cooling systems (engine & oil) capable of 10 plus psi boost depending on pulley size. Just the parts alone cost over $6700.00, raw materials over $450.00 and probably some 120 hours of fab time (not including design & development). I’d price it out at over $13K using a low ball 50$/hr machine/fab rate. I’m expecting around 440 hp with a nice flat torque curve characteristic of a positive displacement blower. Not necessarily the best bang for the buck, but at least I can say “I did it my way”.
However, if I reduced the boost to 5-6 psi, tossed the IC and used the stock intake manifold the cost comes down significantly. With some vendor support (better prices), I think I could offer a bolt on system for under $5.5K. It would include the following;

1) 3rd Gen Eaton M90S Blower w/bypass
2) AEM EMS with baseline S/C programming for otherwise “stock” NSX
3) Accufab 75mm throttle body with Ford TP sensor and harness adapter
4) 440cc RC Injectors
5) High volume fuel pump (optional)
6) 8 rib S/C belt
7) Machined idler pulleys (2)
8) Machined Crank Pully (8 rib belt)
9) Machined S/C mounting plate/belt tensioner (front)
10) Fabricated/machined S/C mounting plate (top)
11) Fabricated TB to S/C intake manifold w/throttle cable mount
12) Fabricated S/C exit manifold
13) Fabricated mandrel bent S/C to stock intake tube
14) Fabricated upper air box housing (need stock cover)
15) Fabricated EGR cover/rear S/C support plate & h/w
16) Fabricated S/C support strut
17) Modified fuel rail (need stock front rail)
18) Relocated oil fill cap to rear valve cover (need stock cover)
19) All necessary H/W, fuel line/fittings, hoses/clamps, etc
20) Engine cover trim template

This would be good for about 350 rwhp with an excellent powerband using a sophisticated Engine Management System. That’s a least $2.5K less than the Comptech and Gruppe M systems. Without the IC, I can get the system under a slightly modified engine cover. In addition, I’ve already designed a very efficient air-to-water IC system that can be added later allowing more boost at safer IATs (or cheaper go air-to-air).
To be fair, the Comptech has an advantage by virtue of a more efficient screw type S/C (I can adapt my mounting plate for any type S/C, but screw types are much more expensive). However, it’s impossible to intercool if you add more boost and you’re stuck with a very rudimentary fuel (not engine) management system that limits reliable output to the same 350hp or so. Even stock, most tuners recommend a high volume/pressure fuel pump since the stock item works VERY hard using the Comptech system. The Comptech is a nicer looking integrated system and fits completely under the engine cover, can’t argue with that. It's CARB approved too! (because they DO use the stock ECU).
The Gruppe M system has a better fuel (and ignition) management system than the Comptech (at least at boost), but it’s not programmable like the AEM. It can be intercooled but I haven’t seen it done with much success. The way the S/C is mounted results in a very torturious path from air cleaner to intake manifold. This drives air temps up and reduces flow and effective boost pressure. There’s no “cold air” intake and while my design won’t win any beauty contests, it’s a bit cleaner than the Gruppe M system. The Gruppe M system is also good for about 350hp as well, I know that for sure (where do you think I got that blower!).
Anyone interested????????

 

[KGP]

Opening Pandora's Box?

Anyone interested????????

I hope you have given thought to the business aspects of your proposition! Once again, I'm quite impressed with what you accomplished. I just don't know why you'd open yourself up to what could be huge hassles for such little reward. But what the hey; Go for it! [Edit]: I say all this with the assumption that you aren't setup as some kind of automotive aftermarket business.

 

[Mark911]

From a product integrity standpoint I have no worries. The Eaton S/C is highly refined and used in countless OEM applications. Reliability is second to none and they have the original manufacture warranty by Eaton. The AEM is another reliable item with a limited manufacture warranty. Most of the other parts are either structural and/or passive in operation and I would need to do some accelerated life testing to guarantee high reliability (or simply design in 100% safety margins). I have no doubt the system itself would be virtually bulletproof.
Now, from a product liability standpoint I would probably need some Philadelphia Lawyer language releasing me from ANY possible damages. Let’s face it, you can’t sue anyone if you get hit by a foul ball or hockey puck because it’s just common sense that anytime you enter a stadium or arena there are risks involved, including possible DEATH! Making major modifications to your engine to increase HP over the OEM should fall under the same assumption of risk. In addition, I have no control over the mechanical aptitude or knowledge of the person doing the installation and possible EMS re-programming. If someone puts the throttle cable on wrong or routes it incorrectly and gets into an accident, I can’t be held liable (unless I was grossly negligent in the basic design, not likely). However, because there are so many people with no common sense, I would require a release indicating that the buyer assumes all risks associated with the installation, usage and servicing of the system (sold as is). If someone objects, they could go somewhere else.
But I’m getting WAY ahead of myself. I don’t even know if there’s demand for something like I described. That’s why I posted sort of a little marketing survey. And you’re right, this would not and could not be anything other than a sideline business for me (for now) as I already have a fulltime job working in the aerospace industry (although my degree is in Automotive Engineering). However, my plan is to develop a “tuner/performance” business in several years for fun and profit after I retire from this wonderful (tongue-in-cheek) industry. I gotta get a good tuner/builder reputation establish as a springboard for my “master plan”. This could be stepping stone number one! (or a clamore).

 

[W]

I congratulate and encourage your efforts. Unfortunately, I would only be interested in a CARB certified kit so that limits me to the Comptech which isn't a bad choice anyways.

 

[PoohBEAR]

Since you are in bellflower, I am interested in looking at it. Private or email me....

 

[Joseph]

Im interested. But since your kit is for the obd1 (91-94 nsx), do you have any plans on making one for obd2(95 up/throttle by wire)?

BTW, It would also be a good idea if you come by the southwest monthly meeting http://www.nsxprime.com/forums/showthread.php?t=42616this this thursday so we can all take a look at your product.

 

[Mark911]

Made 396 hp and just over 300 ft/lbs on the Autowave dyno. This was the final pull after several calibration pulls that we did in rapid succession, so this is a "real world" number. If we let everything cool and did a final "money run" Autowave's experience says we'd be over 400hp easily. The 400 hp didn't surprise me (approx 40hp increase over Gruppe M) but the average 2 psi increase in boost for the same blower and pulley over the Gruppe M numbers was unexpected. I knew my design would unleash the true performance of the Eaton M90, but being ICed, I expected the boost numbers to be closer. Two possible explanations, 1) I screwed up my engines VE somehow or 2) the measurements weren't apples to apples. Based on the dyno charts I don't see any major changes in the basic shape of the curves so the VE theory is a bit hard to swallow in light of the hp gains we saw. On the other hand, I'm now measuring manifold pressure from a point "inside" the plenum where air speed is slowest and pressure the highest. The stock manifold takes its signal at the entrance of the plenum where air speed is much higher and pressure lower. I suspect that real plenum pressure was probably a lbs or so higher than recorded with the original Gruppe M system (and any system using the stock manifold vacuum port). This would explain the anomaly as all my other calculations and expected values were almost right on.
Next test will be with a Magnum Power flow modified M90 housing which should put me up around 10psi with cooler IATs and 440 hp. I’ll stop there.

Just a thanks to Shane and Mike at Autowave, they do the tuning job right!

Shown below are the before (Gruppe M system with AEM, headers/exh) and my system with AEM, headers/exh).

 

[Sig]

Those are great results Mark!

How are the 440's holding up? I would guess that you are close to the ceiling with them.

 

[jcjcf1]

I have no doubt the system itself would be virtually bulletproof. However, because there are so many people with no common sense, I would require a release indicating that the buyer assumes all risks associated with the installation, usage and servicing of the system (sold as is).
But I’m getting WAY ahead of myself. I don’t even know if there’s demand for something like I described.

If you provide sufficient evidence to reasonably support the first statement above, and if you can provide a 350-400 RWHP version that sells for an attractive discount from a CTSC/AEM setup (with the same or better torque curve), and if you can get it on the market with good installation instructions within a reasonable time (next year?), then I am certainly interested. And the liability waiver isn't a problem either.

Do you have definite plans to sell this system, or is this all still in the speculative stage? Please, I'm really interested and I would think there are others as well.

 

[Mark911]

At this point it’s still fairly speculative (unless your talking semi-proto pre production). I need to determine the market demand for something like this and what my costs would be based on that demand. I’m already finding out that if you don’t talk in the order of a hundred units or more per year you’re not going to get much discount on parts. That’s probably the single biggest reason you don’t see reasonable prices on the existing products. However, as the prices of used NSXs become reachable to a younger more performance oriented public this will change, but only up to a point. I also need to know if the market is leaning more towards the “plain Jane” non-IC version (350hp) or the full on IC version (400 plus HP). Of course, if I were doing this only for the money I’d be making kits for the four cylinder imports or Detroit muscle cars. I just can’t get excited about that. I’d rather work with more exotic machines and cutting edge technology. I can say this as fact, however. If I should decided to go forward I’d take the “no wine before its time” approach. I’m already investing over $150K to build a 2000sq/ft workshop that could support such an enterprise (construction ECD April 05). That I’ll be able to show using direct data (several units on the road for X number of miles) plus individual component/system reliability analysis, that the kit (not necessary the engine!) is very reliable. That the kit will perform if properly tuned to the numbers quoted. And that the installation will be well-documented and as simple as possible (at least for the non-IC version). This is not my first “moonlighting” experience as I’ve used my Automotive Eng Degree, technician experience and fabrication skills to do everything from building a 50ft stretch Ferrari Limo to writing automotive repair manuals for Haynes Publications (do a web search under my name MARK CHRISTMAN and AUTOMOTIVE to see some of my publications). I’ll also collect valuable engine reliability data as I track (road course) my car over the next six months starting the 20th of this month at Spring Mountain, Pahrump Nevada (Dali Racing Track day shameless plug). If it’ll break, I’ll break it and figure out why it broke for lessons learned. And there’s always room for refinement. The Eaton M90 that I have on my car is relatively old technology. Newer models are better both thermally and volumetrically but are more expensive. I’d also like to sand cast then post machine several of my fabricated parts to cut labor (my) time. There’s dozens of variables both from an economic and engineering standpoint that must be weighed before I’ll go on record as being “in the business”. Over the next couple of months I hope to have all my questions (and yours) answered. keep asking . . Mark

 

[jcjcf1]

I will be looking forward to your updates. And I applaud the fact that you want to satisfy yourself that you've got it right before offering it to the public.

Guaging the extent of the market, as a business proposition, seems to be more of a problem than the technical aspects.

Please keep the updates coming. Thanks!

 

[ak]

Here are some things I would be concerned with as a buyer.

1. Will this be a turn key system like comptech where you don't need to tinker around after installation and tuning?

2. How will remote support be like? If you sell 100 units, can you support them all at the same time? Are you willing to have someone trained enough to sit for several hours on the phone to work out bugs if you need to? Many of us live in a location where people are not familiar with NSX and will need help...lots of it.

3. Will the serviceablility of the car deteriolate due to the charger being on top? I'd be concerned for oil change, spark plugs, coils maintenance etc.

That being said, I commend you for what you are doing and hope that you'll have a great success. The kit does seem very promising...but then all the F/I kit that has come and go seemed promising in the beginning, not just in NSX community but overall in tuning business.

-ak

 

[Mark911]

Those are great results Mark!

How are the 440's holding up? I would guess that you are close to the ceiling with them.

Your right. I max out at 90% duty cycle right now. I'll need to up my fuel pressure or go to 550s or larger for the 10psi I'm looking for. Mark

Know anyone that wants to sell some good used 550ccs?

 

[Mark911]

Here are some things I would be concerned with as a buyer.

1. Will this be a turn key system like comptech where you don't need to tinker around after installation and tuning?

My actual experience is as follows. I finished installing the system and two days later I was at the dyno at Autowave. Granted, Autowave has quite a lot of experience tuning AEM managed S/Ced NSXs, particularly retrofitted Comptechs. In about an hour my car was putting out nearly 400 screaming hp and it drives great. Since my system uses a programmable ECU, I can't stress enough how important it is to have a competent tuner with the right equipment (dyno [preferably an eddy current], W/B O2s, exh temp, etc). I’ll bundle a basic “starting point” calibration with the AEM, but that would need to be tweeked as NO TWO NSXs are alike, not even stock ones. As with most programmable EMSs, there are many ways to manipulate the various maps, trims and options to achieve virtually the same results. Each tuner seems to have their own preferences based on experience and familiarity with the system and may not feel comfortable with my approach. This is a potential problem area as the same versatility that allows the AEM to extract maximum hp gains and reliability can also lead to confusion and frustration in the wrong hands. On the other hand, positive displacement S/Ced vehicles are easier to tune than turbos as there is no active boost control, the boost (flow) is more linier, and the variables affecting the amount of boost and when the boost is created are much fewer. Consequently, the tuning process is not only simpler, but it envelops probably 90% of the operational conditions the engine will ever see in real life. To envelop 90% of the potential operational conditions a turbo might experience is much more time consuming. It’s like comparing a two dimensional matrix of conditions to a three dimensional matrix. I’m not saying a PD S/C is better than a turbo, just easier to tune and less likely to have tuning anomalies later. The centrifugal S/Cs are kinda in between since they produce flow in a more or less exponential (not linier) manner. Bottom line, the only moving part (beside the blower and drive) is the bypass valve, a very reliable part (and very accessible compared to Comptechs which is under the intake). The 8 rib belt (as opposed to 6) will greatly extend the life of the belt compared to the Comptech. My pulley bearings are heavy duty high quality items, so they should last longer than most OEM models with S/Ced engines. The AEM is the only relatively unknown item in terms of reliability and consistency. Up to now, I’ve only experienced and heard good things.

2. How will remote support be like? If you sell 100 units, can you support them all at the same time? Are you willing to have someone trained enough to sit for several hours on the phone to work out bugs if you need to? Many of us live in a location where people are not familiar with NSX and will need help...lots of it.

Again, the non-IC system will be very simple. Once installed, the only thing to keep an eye on will be belt tension, just like the alternator belt. I’ll include a maintenance schedule that will probably include many of the standard OEM items and durations plus a few more, oil change in the S/C for example. As stated before, I’ll include an EXTENSIVE installation manual and video outlining everything from nuts and bolts to reading sparkplugs and some fundamental tuning (AEM programming) information (remenber - you'll need a tuner to get max performance). I’ve written complete shop manuals in my past so I know what the average guy wants to see to feel comfortable. Personally, knowing how I document things I doubt I’ll be getting many calls other than compliments about well everything was explained and how easy things went together.


3. Will the serviceablility of the car deteriolate due to the charger being on top? I'd be concerned for oil change, spark plugs, coils maintenance etc.

Coils and plugs will be slightly more difficult to service, but not bad. I include relocating the oil filler cap to the rear valve cover in my proposed kit. The only items that would require removal of the S/C and mounting plate would be injector replacement/external service or replacement of the IAT sensor.

That being said, I commend you for what you are doing and hope that you'll have a great success. The kit does seem very promising...but then all the F/I kit that has come and go seemed promising in the beginning, not just in NSX community but overall in tuning business.

Frankly, there doesn't seem to be too much interest at this point (although everyone went nuts on the Jackson Racing Rumor). Too bad. Maybe I'll just publish the blueprints and parts list for anyone to do themselves. I just get pissed every time I see a product for the NSX that's priced at least two times more than it should. I'm just trying to help out the NSX community if I can while keeping my day job.

 

[RichJacobs]

Don't get discouraged by the "lack of interest" on Prime thus far. I just found this thread today 11/13/2004. I would be very interested in getting this puffer on my car. So PLEASE keep moving forward. I'm in San Diego, so if there's a chance to see your beast live, let me know. I keep waiting for a better SC to come along. Perhaps it's crawling out of it's den now.

 

[NetViper]

A lot of people may also be hesitant because of problems with another supercharger system in its infancy. It has taken a few years to work most of the bugs out of that system with some pretty serious problems. Don't give up. Keep doing what you are doing. Run your test mule and let us know how it is going.

I am always looking for a cost effective FI solution.

 

[nsx-animal]

A lot of people may also be hesitant because of problems with another supercharger system in its infancy. It has taken a few years to work most of the bugs out of that system with some pretty serious problems. Don't give up. Keep doing what you are doing. Run your test mule and let us know how it is going.

I am always looking for a cost effective FI solution.

I agree with Netviper, keep moving forward and just learn from the other companies mistakes. I would love to have a kit down here in South Florida.

-Frank

 

[jgtcnsx]

nice. very good work. i still dont like superchargers though. takes power to make power.

 

[Mark911]

nice. very good work. i still dont like superchargers though. takes power to make power.

Understandably, it is widely accepted that any gains from turbo charging is “free” power. While it may be true that the actual process for converting exhaust thermal energy into rotational energy of the turbine shaft is “free”, this conclusion is somewhat misleading. When viewed from a total systems standpoint (the point that really matters), it’s quite evident that turbochargers DO require horsepower to operate. If one were to study the PV (pressure volume) diagrams of a typical normally aspirated, turbocharged and supercharged engine, one would see that the turbocharged engine suffers from greater pumping losses. By nature, one of the unwanted byproducts of a turbocharger is higher exhaust manifold pressures. This not only increases the power necessary to pump freshly burned gasses through the exhaust port but leaves higher residual pressures in the cylinder which the incoming charge must overcome. This all takes horsepower, it’s just on the other end of the power equation. Pumping and friction losses are primary factors in overall power. In fact, one could design an engine (long stroke, really long!) that required so much power to simply overcome ring friction that it simply couldn't run. The same could be said for inefficient filling and empting of the combustion chamber. Bottom line, SC ed engines can be designed to take advantage of modern day exhaust tuning techniques to effectively evacuate the combustion chamber (actually leaving negative pressures) where as a turbocharged engine can’t. That’s one of the reasons the delta HP difference between the two systems at the same boost are less than one might expect everything else being equal (the turbo still has the advantage, however). And don’t get me started on screw vs. roots commonly (i.e. wrongly) held truths . . . . Mark

 

[Black&Tan97Tnewportbeach]

I met Mark with TURBO NSX at the last OC meet, he definitely knows what he is talking about . . its nice to meet another sharp motor guy . . unfortunately I didn't stick around long enough to hear\see his car run, but I have a feeling its really fun. He did however get to see my prototype top-secret "V5" complete with James Bond smoke screen!

 

[jgtcnsx]

i understand that. what i am saying is the average super charger takes 20-30% of the cars hp just to make the supercharger work. with the stock nsx engine overall a supercharger would be better because of the leaner mixture resulting in less exhaust fumes to make the turbo spool up. if the engine is modified, thats a different story. the turbo by far would be better to use. supercharges have better low end response and it is immediate since the supercharger is always compressing air, but turbos are more efficient and can reach higher power then superchargers. what your saying is that the increased exhaust backpressure presented by the turbo also robs power from the crankshaft (since it is now harder to push the piston up to expell the exhaust gases. This argument, however, is overstated. Because the intake air is also under pressure (typically greater pressure until the maximum horsepower engine speed), it pushes the piston down. For the majority of the power band, these two forces cancel on another out. Because turbochargers do not use much of the power output of an engine, the highest power levels are possible when using a turbocharger rather than a suprecharger. the fact is if you want alot of horsepower go with the turbo, if you want a more reliable responsive system go with a supercharger.

 

[RP-Motorsports]

I know of a local guy who too is custom building a SC w/ AEM standalone kit. He will be a year yet before finished. He actually is building it with an OEM SC from a different car. I don't want to give any details, but once the brackets and pully's are built, it will be very inexpensive as far as parts. The $1400 AEM will be the biggest cost. I will keep you posted. It is nice to see others trying!!!

 

[NetViper]

I know of a local guy who too is custom building a SC w/ AEM standalone kit. He will be a year yet before finished. He actually is building it with an OEM SC from a different car. I don't want to give any details, but once the brackets and pully's are built, it will be very inexpensive as far as parts. The $1400 AEM will be the biggest cost. I will keep you posted. It is nice to see others trying!!!

Now that sounds very interesting indeed.

It is great to see all these new options coming up in the future. (if all goes well)

Maybe, if we are really lucky, comptech will lower the price of their SC kit to be inline with every other SC kit they offer.

 

[Mark911]

what your saying is that the increased exhaust backpressure presented by the turbo also robs power from the crankshaft (since it is now harder to push the piston up to expell the exhaust gases. This argument, however, is overstated. Because the intake air is also under pressure (typically greater pressure until the maximum horsepower engine speed), it pushes the piston down. For the majority of the power band, these two forces cancel on another out.

Again, this is true, but when looking at the entire system things are not quite as simple. For example, BOTH the turbo and SC engines will benefit from the intake air charge pressure to reduce intake pumping loses, but only the turbo needs to overcome additional forces due to positive exhaust manifold pressures during it's exhaust cycle. These forces tend to be greatest at higher rpm when emptying time is so short. That's one of the reasons turbos (after they spool up) tend to show greater torque at lower rpms compared to a PD SCer. The turbos got plenty of time to get rid of spent gasses and pumping losses are minimal while the PD SC still needs X amount of hp to drive. As rpm increase, so do the turbos pumping losses. Granted, it's still less than with a PD SC, but the lines tend to converge so to speak. A secondary byproduct is that a turbo system can see cylinder pressures higher than intake manifold pressures during initial intake valve opening due to incomplete exhaust scavenging. This actually results in a minor (but still significant) amount of flow reversal until equilibrium is reached and positive flow can begin. This affects overall system flow (and less effective intake loss reduction). Thus the constant turbo battle between good response (lag) and maximum torque/HP at higher rpms. Very careful design can mitigate but not eliminate this trade.
Don't get me wrong, I agree from a theoretical and practical standpoint that turbos DO give more then they take compared to SCers. My point is only to communicate that the delta difference varies with operational conditions and that it's certainly not "free" power by any means.

 

[jgtcnsx]

i here what you are saying. it is a discussion about superchargers and turbos that will always be in disagreement. superchargers and turbo chargers have different advantages and disadvantges. it basically is what you prefer to use.still, that is one hell of a kit you made there