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AP-X NSX turbo system (angus turbo kit)

I just signed up today because I finally got the car of my dreams a 1991 Acura NSX, I want to start a new thread but I dont know how, I cant seem to fins the button or see the start can anyone help me?
 
What kind of change to the boost curve might we expect? Obviously response similar to what you would find from a modern turbocharged car such as a GTR/997/MP4/M600, starting really low and not running out at the top would be ideal. Would full boost as low as 2500-3000 be possible, or am I dreaming?

If you look at Bob K's car, that is pretty much exactly what he has.
 
If you look at Bob K's car, that is pretty much exactly what he has.

Where might I find a dyno and details of Mr. K's car? I'm digging around without much luck...

:smile:

(EDIT) I found this thread: http://nsxprime.com/forum/showthread.php?p=1402924

His 360lbs/ft of tq is impressive but still coming in at 4000rpm, considerably higher than what you get from one of the modern factory turbocharged cars, or am I missing something?
 
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I suppose what I would find ideal would be full boost at a very low rpm with smooth and flat torque response all the way to redline. The big torque humps at 4000rpm just look very unnatural to me.

Is this possible with available turbos? I'm certainly no turbo expert, but I have heard of twin turbos, twin scroll and variable-vanes, all designed to produce flat torque and decent throttle response, much like what you can get with a supercharger. Of course engineering a turbo system is not a simple feat considering the number of compromises, and while I may be dreaming, I still can't seem to ignore how well Porsche (and other) turbos work. Of course those systems were designed with the engine from the ground up.
 
TAI,

Numbers on paper don't always translate to real world experience. If you want maximum torque at 2500-3000 you WILL have to give it up on the high end.

If it was all about low end TQ numbers Corvette owners would not be so used to looking at OUR tail lights. :eek:

Why is it exactly that sooooooo many P & F car owners scratch their heads when they meet us at mixed track events????? Our cars just work and FI makes them work better.(IMO) If you have ever spent any time on the track you would know most of the time is spent between 5k and redline, not 2500 and 4500.

There have been countless posts on this board from tuners to people with MBA's in Engineering that can explain turbo sizing countless ways. The bottom line is that there is no perfect solution for everyone.

I am quite happy with 400 rwhp when other FI members would find this quite boring. Seek what you ultimately want, build it, report back.

I hope this helps.
 
The power curve with the "custom" PTE turbo I am now providing will not be altered much at all.

There are other options avaialble to tailor the curve in any way desired although my own preference is to keep the power curve as close as possible to stock so as to not alter the "feel" of the car.
 
The power curve with the "custom" PTE turbo I am now providing will not be altered much at all.

There are other options avaialble to tailor the curve in any way desired although my own preference is to keep the power curve as close as possible to stock so as to not alter the "feel" of the car.

I still do not agree at all that your kit doesn't alter the feel of the car. The CTSC doesn't alter the feel of the car. A turbo does. NO turbo I have been in feels like a stock NSX power curve. My 2 cents.
 
I still do not agree at all that your kit doesn't alter the feel of the car. The CTSC doesn't alter the feel of the car. A turbo does. NO turbo I have been in feels like a stock NSX power curve. My 2 cents.

Perhaps stating that the turbo is designed to minimize the change from the stock feel of the car would be more accurate, but I think everyone here is aware that any turbo will inherently change a car's natural response. I'm just curious if it's possible to get more boost across a wider percentage of revs like a supercharger.

Of course there's no doubt that these turbo's put the NSX back in the game with modern supercars, and I think that's absolutely great! Check out this dyno from a F458 vs ZR1. The F458 has 317wtq at 4k, far less than Bob K's 370wtq also at 4k! :biggrin:

http://forums.corvetteforum.com/c6-corvette-zr1/2682733-zr1-vs-ferrari-458-a-3.html
 
I still do not agree at all that your kit doesn't alter the feel of the car. The CTSC doesn't alter the feel of the car. A turbo does. NO turbo I have been in feels like a stock NSX power curve. My 2 cents.

The CTSC does not alter the feel?

So you are saying the car has big bottom end torque and not as much top end from the factory?

This difference in perception is exactly the reason why I am offering the option to choose any turbocharger you would like with my kit.
 
The CTSC does not alter the feel?

So you are saying the car has big bottom end torque and not as much top end from the factory?

This difference in perception is exactly the reason why I am offering the option to choose any turbocharger you would like with my kit.

The ctsc does have more tq but that tq curve is very similar to stock. There is just more power everywhere, but the power delivery is very similar to stock.

The turbo tq curve looks nothing like stock. waiting for the turbos to spool feels nothing like stock.

I am not saying it is bad. I really like the way the turbo feels. I was very impressed with both angus kit cars i have been in. I love how hard they pull at high rpm. They are very fast and a great price. They are faster than any ctsc car I have been in.

But it doesnt feel like stock with more power like a ctsc does. Just my opinion.
 
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I suppose what I would find ideal would be full boost at a very low rpm with smooth and flat torque response all the way to redline. The big torque humps at 4000rpm just look very unnatural to me.

Is this possible with available turbos? I'm certainly no turbo expert, but I have heard of twin turbos, twin scroll and variable-vanes, all designed to produce flat torque and decent throttle response, much like what you can get with a supercharger. Of course engineering a turbo system is not a simple feat considering the number of compromises, and while I may be dreaming, I still can't seem to ignore how well Porsche (and other) turbos work. Of course those systems were designed with the engine from the ground up.
Sounds like a GT30 could fit your needs - like Spoon's NSX-R GT that I drove (~400whp if not just under). Great low end and runs out of steam up top, like the characteristics of a Porsche Turbo you were looking for.


0.02
 
Thanks for your input Billy, I would like to see someone try that setup, might be a nice street setup.
 
I just ordered the SOS 6 Puck clutch. I was a little bit torn between that one and the standard SOS Sport clutch. BOB K puts down slightly more HP and TQ numbers than I have and from what I understand he is happy with the sport clutch. In the end, I just wanted a higher margin of safety and I was willing to give up a little bit of drivability in case I go higher in power down the road.

My stock NSX clutch held up very well to 400+RWHP until I went to Bradenton Motorsports and after my 2nd 1/4mi. run she started to slip. That tends to happen when you rev to 5k and drop the hammer. The last several months I just turned the boost down to 4psi or so and the stock clutch has held fine..............and power is still nice enough to beat an M3. :smile:

I am having my Acura dealer in Sarasota, FL install the clutch in a few weeks. I'll report back when I put a few hundred miles on her and turn the boost back up to the 7's. All in all, the Angus turbo has been a pleasure and I have YET to be beat stoplight to stoplight!
 
Thanks for the input on the kit - I just put about 100 miles on the car today!
 
I've been driving the crap out of mine for over a year and a half now.. no kit related issues to report. I let a friend drive it the other day on the way back from an event and it was a totally different experience from the passenger seat. That car is damn fast. :biggrin:
 
yep! been driving mine lots this season! put 3000kms on it already, thats more than the last 2 years together?!

It is as reliable as day 1 and always puts a smile on my face!

There's nothing like a turbo NSX! Period.
 
The car is fine for street driving, I haven't have a problem with temperatures on the street.
On the dyno and the track it's a completely different story, the car was extremely heat soaked in about 4-5 pulls and on the track the car start it overheating on the third lap, I had to put it in fifth and just drove it around track until the temperature came back down.

The intercooler can not take the heat that 450whp can make, with the help of Rob we will be making a water/air cooler.

I guess I did know this, but I had high hopes I guess.

-MSR
 
I suppose what I would find ideal would be full boost at a very low rpm with smooth and flat torque response all the way to redline. The big torque humps at 4000rpm just look very unnatural to me.

Is this possible with available turbos? I'm certainly no turbo expert, but I have heard of twin turbos, twin scroll and variable-vanes, all designed to produce flat torque and decent throttle response, much like what you can get with a supercharger. Of course engineering a turbo system is not a simple feat considering the number of compromises, and while I may be dreaming, I still can't seem to ignore how well Porsche (and other) turbos work. Of course those systems were designed with the engine from the ground up.

The very first turbo system for the NSX was actually a variable vane system using 2 Aerocharger turbochargers. Problem was tuning but that has now been solved with the standalones or the FIC. Aerocharger is back in business so if you want to spend the money, you can get full boost by 2500 RPM with a flat torque curve and some decent HP. Going to their site, they have a kit for the Porsche 930 turbo with full boost by 2500 RPM and a flat torque curve. Benefit of the Aerocharger, fast boost and no issues with oil return since they are self contained. Downside is truly the cost, 5K for the turbochargers alone.
 
haha I put over 100miles a week. I drive it year round here in texas. 2.5 years still going strong
 
I still drive mine every so often, but the car is mainly parked since I bought myself a new daily driver with A/C.

I've made SEVERAL trips to Dallas and back though, and no issues, problems or hiccups.

Throughly happy with my kit, except for it's a big laggy IMO. But man, when she gets up there, SHE GETS UP THERE lol
 
If anyone is interested, I have some spare parts on the shelf so I can do a discounted kit.

PM me for details.
 
Just wanted to update my progress on the kit - for those who want a faster spooling option, my new turbos will be ready soon, I am getting set to dyno one in the next few days, there will now be two options, the original design with an updated A/R ratio and a Precision turbo based on their housings but using my compressor wheel trim.

The difference should be improved spooling with no reduction in high RPM boost.
 
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Actually, I have made some progress - I am getting ready to post some results but initially I have seen about 1K rpm in spooling improvement.
 
I am putting together some really great deals on the turbo kit soon!
 
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