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Mugen or comptech
- Thread starter sonik
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-Which supercharger would you rather have? also what is the cost on each...I believe the mugen one is 9,500
Does Mugen make a supercharger? I've never heard of that. Or are you thinking of the one from Gruppe M?
There's info on the Gruppe M and Comptech superchargers in the FAQ.
Does Mugen make a supercharger? I've never heard of that. Or are you thinking of the one from Gruppe M?
There's info on the Gruppe M and Comptech superchargers in the FAQ.
I got the Comptech unit, look at how clean it is compare to Grupple M with all those piping going every where. Power is about the same, so why mess with Grupple M. The comptech is probably more proven as most people go with the comptech unit unless you want to be special and run a Grupple M. Special doesn't mean better.
Originally posted by Khuang:
I got the Comptech unit, look at how clean it is compare to Grupple M with all those piping going every where.
Aesthetics is one thing, but the two units were designed with different agendas in mind. The Comptech unit was designed to maintain the "stock" looks of the engine compartment, but several compromises had to be done in order to achieve that. Among them, is a "special" intake manifold that allows the blower to be mounted down low into the engine to allow the use of the cover. That is good and dandy, but it is actually a chopped up stock intake manifold that will never flow as good as the factory intake manifold. Another compromise is the close proximity of the blower to the engine, which precludes the possibility of adding an intercooler. With the design of the Gruppe M kit, an intercooler is very possible with little design alterations, allowing for even more horsepower.
Still another compromise is the drive belt system. Because of space limitations, the CT unit utilizes a thin, 6-rib belt, passing through a tortuous passage between idler and drive pulleys. Belts breaking with the CT unit is not an uncommon thing. The belt of the Gruppe M SC is a hefty 9 rib, with a much simpler layout that produces a lot less stress than the other. Thus a much more reliable set up.
Still another difference is in the engine management system. The CT kit uses a simple mechanical way of providing fuel enrichment via a boost dependent fuel regulator. No provision is made for timing variations needed under boost conditions. In line with the sophistication of NSX technology, the Gruppe M kit has a sophisticated electronic engine management system that is used in conjunction with the factory ECU, that adjusts fuel, timing AND boost according to conditions. Also, it expands the flexibility of the ECU so that it will be more responsive to ROM changes.
All this means is that more (usable) power will be on tap through increased efficiency, not just through a brute increase in boost.
Power is about the same, so why mess with Grupple M.
Not quite. The Gruppe M will produce more horsepower at the same boost as the Comptech. My Gruppe M SC'ed NSX produces over 370 HP of non-intercooled power at the rear wheels, and that's at only 6.5 lbs of boost. A "9 psi" CT unit won't even come close.
But where the Gruppe M kit really shines is in the torque. It will consistently out-torque the CT unit by at least 50 lbs-ft. at the wheels, with a flatter torque curve from 2500 RPMs and up all the way to 7500 RPMs. And torque is what actually drives the wheels, and is what the NSX engine badly needs.
The comptech is probably more proven as most people go with the comptech unit unless you want to be special and run a Grupple M.
In Japan, there are over 70 installed units over there. No problems are reported; as a matter of fact, there are a few NSXs with about 80K miles on the supercharger and are running just fine. Compression tests indicate healthy motors in these cars.
Special doesn't mean better.
In this case it probably does
The two kits are probably designed with different owners in mind. If you want simplicity, and if the stock appearance is important to you, then perhaps the CT is the way to go. But if you're an owner who wants sophistication and that extra margin of performance, then perhaps the Gruppe M is the way to go.
Hope this helps.
its 9500 right...where would the intercooler mount that would benefit the supercharger...I dont think running piping to the front would be a very good idea..But I do think that I am going to go with the gruppem because I dont want my car to be, or look stock....
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I am certainly not trying to start an argument here, but I am curious... Hayashi says his car put out 380 HP and 249 lb/ft at the wheels on his last dyno run with just a k&n, mostly straight-through exhaust and the CT IEM and 9 lb kit (and a bunch of gauges for tuning).
Not quite. The Gruppe M will produce more horsepower at the same boost as the Comptech. My Gruppe M SC'ed NSX produces over 370 HP of non-intercooled power at the rear wheels, and that's at only 6.5 lbs of boost. A "9 psi" CT unit won't even come close.
370 rwhp, What is the car making before the supercharger? I am thinking the 6.5 psi is equivalent to .442 bar, so the maximum ideal increase in hp is 44.2 % hp and that is idea with no increase in air restriction or heating up the air. Without the Intercooler or even with it, you can't achieve 44.2% increase at 6.5 psi unless you intake efficiency is increased alot more than the decrease in efficiency of heating up air. One can dyno high hp in high elevation with the correction in hp due to altitude, what altitude and what correction factor?
The Comptech unit is alot simplier in terms of fuel management, but I dynoed 334 rwhp and 240 ft-lb of torque on 93 octane gas and 321 rwhp and 237 ft-lb of torque on 92 octane gas with no correction factor. The simple fuel system did its job. I have the 6 psi kit, but don't have a boost gauge to tell the actual psi reading.
Intercooler is awesome, I wish I can have one mounted in a good position, but there ain't any without making the engine bay looks weird. If you goal is maximum power, go with a turbo.
The bad thing about CT is the weak belt, I change it at every oil change, other than that, I don't see any. Simple fuel management has not hurt me yet. Checking out other Grupple M supercharger's dyno chart is very similiar to my. So I am happy customer.
My preference is Comptech unit as their benefits suit my needs. There will be a few that like Grupple M, but I guess more like Comptech as there are more units sold here. Also didn't Mark Basch just went from Grupple M to Comptech, what was his reason? I personally don't know but that would be a good guy to talk to.
370 rwhp, What is the car making before the supercharger? I am thinking the 6.5 psi is equivalent to .442 bar, so the maximum ideal increase in hp is 44.2 % hp and that is idea with no increase in air restriction or heating up the air. Without the Intercooler or even with it, you can't achieve 44.2% increase at 6.5 psi unless you intake efficiency is increased alot more than the decrease in efficiency of heating up air. One can dyno high hp in high elevation with the correction in hp due to altitude, what altitude and what correction factor?
The Comptech unit is alot simplier in terms of fuel management, but I dynoed 334 rwhp and 240 ft-lb of torque on 93 octane gas and 321 rwhp and 237 ft-lb of torque on 92 octane gas with no correction factor. The simple fuel system did its job. I have the 6 psi kit, but don't have a boost gauge to tell the actual psi reading.
Intercooler is awesome, I wish I can have one mounted in a good position, but there ain't any without making the engine bay looks weird. If you goal is maximum power, go with a turbo.
The bad thing about CT is the weak belt, I change it at every oil change, other than that, I don't see any. Simple fuel management has not hurt me yet. Checking out other Grupple M supercharger's dyno chart is very similiar to my. So I am happy customer.
My preference is Comptech unit as their benefits suit my needs. There will be a few that like Grupple M, but I guess more like Comptech as there are more units sold here. Also didn't Mark Basch just went from Grupple M to Comptech, what was his reason? I personally don't know but that would be a good guy to talk to.
$10K for the SC and $1500 for the 9 psi kit. I think one can get $1K off the SC price. I think one can't run 91 octane with 9 psi kit without alot of detonation thus retard timing. I believe the NSX comes from the factory recommending 92 octane gas. Also I have heard the Comptech SC really can't do 9 psi and if you are in Utah, what is your elevation? If it can or barely do 9 psi at sea level, at elevation, you might be done to 6 psi.
I think the cost of the 2 superchargers are about the same.
Thanks,
one more question that I have...well maybe a couple of questions is this:
-will the supercharger reach its full potential without headers and exhaust or will the stock ones flow good enough..
-I am at 5280 above sea level..and it sucks
one more question that I have...well maybe a couple of questions is this:
-will the supercharger reach its full potential without headers and exhaust or will the stock ones flow good enough..
-I am at 5280 above sea level..and it sucks
No, if one can gain 20 rwhp with header and exhaust, with no exhaust energy, it will cause restriction. If you are at 5280 feet, I doubt you would even get 300 rwhp. I would look into the possibility of turbo, a large enough turbo in which you won't lose any hp at that elevation. For instance, the 996 Porsche Twin turbo should not lose hp until past 8,000 feet (advertised).
Flatter than this?
This is an old dyno run from when I had a CT blower on my 3.0L motor. I'd say that was a pretty flat torque curve.
[This message has been edited by David (edited 01 March 2001).]
[This message has been edited by David (edited 02 March 2001).]
[This message has been edited by David (edited 02 March 2001).]
Number9
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This is another CT dyno run on an NSX with only the S/C:
http://www.dynospotracing.com/blownnsx.htm
Can't get much flatter than that. As for peak HP, as mentioned earlier, DH on nsxfiles.com is claiming 380 rwhp for CT 9 lb kit. I think both kits are capable of pretty good results with adequate tweaking...
--twc
http://www.dynospotracing.com/blownnsx.htm
Can't get much flatter than that. As for peak HP, as mentioned earlier, DH on nsxfiles.com is claiming 380 rwhp for CT 9 lb kit. I think both kits are capable of pretty good results with adequate tweaking...
--twc
Wow, I can't believe CT uses a FMU unit to add fuel. That is terrible. I have a supercharged Corvette and it came with a FMU unit, I threw it in the garbage and took my car and had a professional tuner add fuel and remove timing at each rpm interval through the ECU. That is the only way to do it, never rely on mechanical device to add something so crucial as fuel. The powercurve actually requires different fuel and timing at different rpm's to eliminate detonation at all levels and that cannot be done through a mechanical device. I drive in supercharged cars hooked up to inline diagnositc software (viewed inside the car with a laptop computer) and the cars detonate all through the rpm band when using boost timing retard boxes and FMU units. Wow, $10K and you get a FMU unit, I am disappointed. Go GruppeM!!
I tuned mine on a dyno (as it should be done) with diagnotic equipment and had no predetonation at all. Mechanical FMUs are used with almost every aftermarket blower kit and are not a problem if you tune them correctly.
The best solution, of course, is to go to a fully programable management system like Haltec or SpeedPro.
To me, the a much more important issue would be that the core of the Comptech system (a Whipple twin-screw design) is significantly better than the core of the GruppeM design (an Eaton unit). Eatons are used on some OEM applications because they are cheap and fairly reliable, but the Whipple unit is possibly the best blower on the market. It is a fundamentally better design and is manufactured to increadibly high standards.
[This message has been edited by David (edited 02 March 2001).]
The best solution, of course, is to go to a fully programable management system like Haltec or SpeedPro.
To me, the a much more important issue would be that the core of the Comptech system (a Whipple twin-screw design) is significantly better than the core of the GruppeM design (an Eaton unit). Eatons are used on some OEM applications because they are cheap and fairly reliable, but the Whipple unit is possibly the best blower on the market. It is a fundamentally better design and is manufactured to increadibly high standards.
[This message has been edited by David (edited 02 March 2001).]
Number9
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The CT kit has been fairly well debugged and is now pretty much plug-and-play and does not prevent you from being able to store the T-top in the standard location if you've got the targa.
If you don't care about keeping stock-like packaging, then just skip the GM SC and go straight to the turbo. The latter has much better power potential and since both have ridiculous amounts of plumbing and require a whole lot of tuning, why bother with the lower powered solution at all?
--twc
[This message has been edited by Number9 (edited 02 March 2001).]
If you don't care about keeping stock-like packaging, then just skip the GM SC and go straight to the turbo. The latter has much better power potential and since both have ridiculous amounts of plumbing and require a whole lot of tuning, why bother with the lower powered solution at all?
--twc
[This message has been edited by Number9 (edited 02 March 2001).]
The dyno chart posted on this thread for the Gruppe M SC is an outdated one. We had a small problem with the relief valve then that led to loss of boost in the top end, thus the plateau in the HP curve.
Check this one out instead. We made 364 rwhp on this run, with 289 lbs-ft of torque. We continued to tune it since then, and we made a few more ponies since.
http://badasshondas.com/sdnsx/GruppeM/gruppegraph.htm
Check this one out instead. We made 364 rwhp on this run, with 289 lbs-ft of torque. We continued to tune it since then, and we made a few more ponies since.
http://badasshondas.com/sdnsx/GruppeM/gruppegraph.htm
Exactly! If any of you have anymore questions about the Gruppe M SC, private email me. Thanks.
There is more to Doug's car than meets the eye. It was in completely "race" trim without mufflers and catalytic converters. Too loud for the street. And I think it was leaned out to the limit, and is at about the maximum a CTSC can ever produce. That's according to Larry Garcia of NSX Modified, the tuner of both our cars.
So it is not really an apples to apples comparison.
