Supercharger: Comptech VS SOS

[Hrant]

Another comment regarding posting rwhp. This has been discussed numerous times before; it really doesn't matter if your rwhp is 20 hp more than the next FI NSX for there are zillion of variables that may actually show in real time same day Dyno/road tests that the one with less rwhp is actually a stronger motor than yours - when such variables are held constant. What matters is how much you gained from your baseline (before/after).

In my scenario, 107.7 gain in rwhp was more that I expected - the norm is indeed 80-100. I attribute this mostly to Shad's fine tuning (he helped develop the software), and in part to the CompTech header which was their last batch before the company folded and I was told they really tried to port it cleanly.

Having said this, there are indeed some motors that are stronger even from the factory; don't ask me why but we have seen oem motors that produce as much as 20 rwhp more than other stock motors on the same Dyno the same day.

But I would like to hear the actual readings of boost on your gauges with Autorotor.

 

[RYU]

Another comment regarding posting rwhp. This has been discussed numerous times before; it really doesn't matter if your rwhp is 20 hp more than the next FI NSX for there are zillion of variables that may actually show in real time same day Dyno/road tests that the one with less rwhp is actually a stronger motor than yours - when such variables are held constant. What matters is how much you gained from your baseline (before/after).

In my scenario, 107.7 gain in rwhp was more that I expected - the norm is indeed 80-100. I attribute this mostly to Shad's fine tuning (he helped develop the software), and in part to the CompTech header which was their last batch before the company folded and I was told they really tried to port it cleanly.

Having said this, there are indeed some motors that are stronger even from the factory; don't ask me why but we have seen oem motors that produce as much as 20 rwhp more than other stock motors on the same Dyno the same day.

But I would like to hear the actual readings of boost on your gauges with Autorotor.

Funny you mention boost. We had a discussion about my boost levels a few weeks ago.
http://www.nsxprime.com/forum/showt...ics-dyno-graphs-and-overall-disbelief-inside)

Unfortunately, I don't have an open stretch of deserted street here in SoCal where I can hit redline in 3rd gear to verify this. The deserted streets/hwys are at least 3000-6000ft elevation which would provide erratic boost readings.

Have you noticed varying boost levels depending on where you pick up the pressure from? i.e. vacuum line or from the IM itself..

 

[TURBO2GO]

Yes Hrant 107.7 is incredible, and you are lucky shad is available to you. I gained even more, 112, but that's from bone stock and into a $3000 header and larger intake, etc.

 

[Hrant]

Funny you mention boost. We had a discussion about my boost levels a few weeks ago.
http://www.nsxprime.com/forum/showt...ics-dyno-graphs-and-overall-disbelief-inside)

Unfortunately, I don't have an open stretch of deserted street here in SoCal where I can hit redline in 3rd gear to verify this. The deserted streets/hwys are at least 3000-6000ft elevation which would provide erratic boost readings.

Have you noticed varying boost levels depending on where you pick up the pressure from? i.e. vacuum line or from the IM itself..

Check my comment on the other thread. YMMV :wink:

As for the location of the pick-up pressure, no we didn't do different tests - at least I am not aware of any.

 

[Blacknot]

Another comment regarding posting rwhp. This has been discussed numerous times before; it really doesn't matter if your rwhp is 20 hp more than the next FI NSX for there are zillion of variables that may actually show in real time same day Dyno/road tests that the one with less rwhp is actually a stronger motor than yours - when such variables are held constant. What matters is how much you gained from your baseline (before/after).

In my scenario, 107.7 gain in rwhp was more that I expected - the norm is indeed 80-100. I attribute this mostly to Shad's fine tuning (he helped develop the software), and in part to the CompTech header which was their last batch before the company folded and I was told they really tried to port it cleanly.

Having said this, there are indeed some motors that are stronger even from the factory; don't ask me why but we have seen oem motors that produce as much as 20 rwhp more than other stock motors on the same Dyno the same day.

But I would like to hear the actual readings of boost on your gauges with Autorotor.

Im running no cats. My boost on my gauge hit 8lbs but after about 6,500 it drops down to 7.5lbs. I agree on dynos. I use them to tune and when im done i measured mine with a 140-150 IAT which is what it is when im driving on the average

 

[RYU]

Im running no cats. My boost on my gauge hit 8lbs but after about 6,500 it drops down to 7.5lbs. I agree on dynos. I use them to tune and when im done i measured mine with a 140-150 IAT which is what it is when im driving on the average

a high boost ctsc at only 140-150f is darn good. I'd say your meth/water is working. I've heard from trusted sources the old 1.6L Whipples can see 210f+ at 9lbs on the street in 2nd gear.

 

[bngl3rt]

Maybe, I am not sure but certainly Dave has put together something really nice. Not cheap, but nice.

I assume you've looked into this and maybe you can share... what's involved in getting Dave's system onto one's own car? I assume it's more than just a parts list that has to be ordered from a bunch of individual vendors.

 

[RYU]

I assume you've looked into this and maybe you can share... what's involved in getting Dave's system onto one's own car? I assume it's more than just a parts list that has to be ordered from a bunch of individual vendors.

PM DDozier for best results. He's a well respected member here and one of my personal NSX mentors when it comes to fuel management tuning.

- - - Updated - - -

Btw... resale value is probably better preserved with a CTSC kit...followed by a well documented tune on a SOS kit...followed far behind by most turbo kits (just so many wildcards involved w/ any given turbo kit).

 

[TURBO2GO]

I think beyond the CTSC which is a KNOWN quantity (no tuning involved and well proven) anything else hurts resale value a lot more. I mentioned this before. As soon as tuning or internal engine work are involved, you are going to lose big resale value. CTSC is the only kit that can probably somewhat preserve this. Otherwise you have to start going into long explanations of what the car has had, whose done it, etc. It's also the only kit you can just leave on the car and sell legally to anyone in the U.S. No matter how you look at it, that next step in FI is just a big one.

 

[Blacknot]

I think beyond the CTSC which is a KNOWN quantity (no tuning involved and well proven) anything else hurts resale value a lot more. I mentioned this before. As soon as tuning or internal engine work are involved, you are going to lose big resale value. CTSC is the only kit that can probably somewhat preserve this. Otherwise you have to start going into long explanations of what the car has had, whose done it, etc. It's also the only kit you can just leave on the car and sell legally to anyone in the U.S. No matter how you look at it, that next step in FI is just a big one.

Very true statement. I bought my car with the Comptech SC already on it. Knowing the history of the kit and how safe it is I never thought twice. I would be hesitant to buy a turbo car because you never know how high the boost was or if the tune has done any damage

 

[ozone]

Serious question. I did a lot of research on Prime, SOS vs CTSC over the past couple of years. From my understanding, most people considered the SOS system to be quite safe, a more powerful version of CTSC that required a tune. I have a SOS SC with FIC (no EMS for New York state emissions) and the install was done by a very reputable Prime member. Car dyno's at 360rwhp.

I plan to keep my NSX forever (at least that's the current plan)--so I'm more concerned with the health of my car than resale value. Would I be better off swapping out the SOS SC for a CTSC and going back to the stock tune? I've driven under a 1K miles on it since SC installation and now the car is out for the season because of snow. Again, I'm not trying to sound too naive but I really want to do what's in the best interest for the NSX long-term while maintaining extra power that comes from a SC.

 

[NetViper]

Serious question. I did a lot of research on Prime, SOS vs CTSC over the past couple of years. From my understanding, most people considered the SOS system to be quite safe, a more powerful version of CTSC that required a tune. I have a SOS SC with FIC (no EMS for New York state emissions) and the install was done by a very reputable Prime member. Car dyno's at 360rwhp.

I plan to keep my NSX forever (at least that's the current plan)--so I'm more concerned with the health of my car than resale value. Would I be better off swapping out the SOS SC for a CTSC and going back to the stock tune? I've driven under a 1K miles on it since SC installation and now the car is out for the season because of snow. Again, I'm not trying to sound too naive but I really want to do what's in the best interest for the NSX long-term while maintaining extra power that comes from a SC.

I think you are fine, but 360 seems really low for an SOS sc. How much boost are you making?

 

[ozone]

I think you are fine, but 360 seems really low for an SOS sc. How much boost are you making?

I don't know what it was exactly set at but the boost gauge is 9-10 psi.

 

[L_RAO]

How about getting your car properly tuned on an EMS and simply having the FIC re-installed for the purposes of smog tests?

Serious question. I did a lot of research on Prime, SOS vs CTSC over the past couple of years. From my understanding, most people considered the SOS system to be quite safe, a more powerful version of CTSC that required a tune. I have a SOS SC with FIC (no EMS for New York state emissions) and the install was done by a very reputable Prime member. Car dyno's at 360rwhp.

I plan to keep my NSX forever (at least that's the current plan)--so I'm more concerned with the health of my car than resale value. Would I be better off swapping out the SOS SC for a CTSC and going back to the stock tune? I've driven under a 1K miles on it since SC installation and now the car is out for the season because of snow. Again, I'm not trying to sound too naive but I really want to do what's in the best interest for the NSX long-term while maintaining extra power that comes from a SC.

 

[ozone]

How about getting your car properly tuned on an EMS and simply having the FIC re-installed for the purposes of smog tests?

Honestly that's more headache than I want to engage in on a yearly basis. Plus, I don't have a local tuner. I had all the work done about 6 hours away.

 

[TURBO2GO]

If you've had your AFR's checked and feel the tune is good I see absolutely no reason to go backwards to an FMU. If you are at a place where temperatures fluctuate wildly, you may want to keep an eye on it in the winter. What you don't want is to ever go lean. Unfortunately most tuners want to give their client the most power do they push the envelope a bit. I think as long as your fuel quality doesn't drop down low and the temp doesn't drop too low, and you aren't on a track, you're fine. Do you have an AFR gauge? Proper instrumentation is really important in any tuned FI system. I don't have anything. Not even a boost gauge. My AFR's were so consistent on the dynos and over a year with the FMU I sold my AEM AFR gauge.

 

[RYU]

I don't know what it was exactly set at but the boost gauge is 9-10 psi.

360whp at 9lbs is quite low. However, if I'm thinking of the same tuner he probably backed down the timing which is ok in my book.

 

[NYCNSX]

Great informative thread, much appreciated! If anyone is looking to pull their CTSC and upgrade to something else I am looking for a 1.7 complete kit that has either been rebuilt recently or has low mileage on it. Please shoot me a PM.

 

[ozone]

360whp at 9lbs is quite low. However, if I'm thinking of the same tuner he probably backed down the timing which is ok in my book.

Our goal was to run rich to avoid problems, as well as have it pass emissions easily. I realize there is some room for increasing the power.

I have a boost gauge and a variable AFR gauge but it unfortunately doesn't give the number.

 

[RYU]

Our goal was to run rich to avoid problems, as well as have it pass emissions easily. I realize there is some room for increasing the power.

I have a boost gauge and a variable AFR gauge but it unfortunately doesn't give the number.

Giving up some HP for added safety is something I'd do as well. You don't want to run too rich for any extended amount of time though. 360 is plenty of HP but I'm curious why not run on a lower 7lbs of boost, achieve the same HP, cooler IAT, and run closer to stoic?

Is it because the SOS blower is out of its optimal range when run below 9lbs?

 

[peiserg]

360 is plenty of HP but I'm curious why not run on a lower 7lbs of boost, achieve the same HP, cooler IAT, and run closer to stoic?

?

Plenty of HP? Uh. No. Your first digit is broken. If you change it to a "5" I might agree.

 

[RYU]

Plenty of HP? Uh. No. Your first digit is broken. If you change it to a "5" I might agree.

But people lift their Quad Cab Duallies 4x4 by 6" with 38" tires too

- - - Updated - - -

Thanks to the good folks at Kenne Bell I found some info I could sink my teeth into.

Cliff Notes:
-there IS an optimal size blower for each respective goal and application. Bigger is not always better.
-reducing parasitic drag is key which can be done by better overall design or lessen internal friction (ran-up?)
-intake restriction is a consideration (I think both ctsc and Sos can benefit significantly from a bigger TB... next on my project list)

There's a ton more info here where they go into better detail about sizing superchargers appropriately.
http://www.kennebell.net/KBWebsite/Common/pdfs/28H_vs_33_34.pdf

 

[TURBO2GO]

One last thing I want to add before this thread dies: the CTSC's huge advantage is that there is no tuning. When you go to sell a vehicle with a CTSC, anyone can buy it, service it, inspect it, and parts are available from a large supplier as Comptech engineering.

Once you tune with aftermarket management, someone else buys the car, they may not have access to you local tuner. If it is a custom turbo kit, which all are, and that builder is no longer around, you may have difficulty getting parts. In general, between the tuning and the specific parts, buying a used FI vehicle other than the simple CTSC kit is a whole other game.

This is one of the main things that has made me stick with my CTSC and not go to the next step.

 

[NYCNSX]

This is exactly why someone like me is looking for a CTSC. I am looking for OEM reliability without the need of having to ever get the car tuned. I am sure additional power can be extracted from a supercharger set up with extra fuel and tuning however the simplicity of the CTSC appeals to me. Coming from the world of Supras I enjoyed a BPU set up above a single that required tuning due to the simplicity as well.

One last thing I want to add before this thread dies: the CTSC's huge advantage is that there is no tuning. When you go to sell a vehicle with a CTSC, anyone can buy it, service it, inspect it, and parts are available from a large supplier as Comptech engineering.

Once you tune with aftermarket management, someone else buys the car, they may not have access to you local tuner. If it is a custom turbo kit, which all are, and that builder is no longer around, you may have difficulty getting parts. In general, between the tuning and the specific parts, buying a used FI vehicle other than the simple CTSC kit is a whole other game.

This is one of the main things that has made me stick with my CTSC and not go to the next step.

 

[docjohn]

afaik the standard ct blower setup will lose power after just a few hot laps at the track,,,,heat soak i guess..but another data point to consider if you are a track person who thinks just bolting on the blower will give you the extra power you need.