at the Dyno with Taitec exhaust

[austrian type-r]

First I want to say hello to you NSX drivers and those who wants to become NSX owners.

I am Christian from Austria and I am 26 years old. I bought my red 1991 NSX back in September 2004 with 55000km on the clock, all stock except exhaust tips.

mods I did so far:
Volk ce28n 7.5x16 offset 46mm front rolling on oem Yoko A022 215/45/16
Volk ce28n 9x17 offet 40mm rear rolling on oem Yoko A022 245/40/17
Procar carbon airbox with carbon snorkel and Apexi filter
Taitec header
Taitec light weight exhaust
Bilstein dampers on lower perch with oem springs
removed spare wheel & bracket
removed engine cover
removed tools
Alpine MP3 changer (yep, works with oem radio unit)

adjusted the suspension to my taste, slightly oversteer, so should it be IMO.
front toe out: - 4mm total
front camber: - 1,2 degree
rear toe in + 6,8mm total
rear camber: - 1,5 degree


mods I want to do
2002+ rear valence
NSX Zanardi edition suspension springs
NSX Zanardi floor mats
Cantrel studios L-shaped carbon front lip
Cantrel studios narrow/lexan engine cover
Cantrel studios coolant tank (red wrinkle)

here are some actual pics of my ride.

http://www.voehr.com/upload/auto//Firma_NSX1.jpg__scaled_800.jpg

http://www.voehr.com/upload/auto//NSX_Wien_2.jpg__scaled_800.jpg

http://www.voehr.com/upload/auto//Terschl_1.jpg__scaled_800.jpg



Here you can see what I did to my NSX in the winter-time.

I already heard of a few bad storys about changing out the header on NSX, cause it is a pain in the ass. I dunno what people have. of course there are sme parts you have to remove like rear engine mount with frame, left cat, etc. IMO it is a nice work, cause all the parts are easy to rich. Some oil on all of the exhaust bolts and carful removing them should prefent from breaking bolts. I also heard rumors people doing header removing on the floor just with jackstand?! I think that is BS.


I did that today in the afternoon:

- removing front engine mount (wow, could reach it with airwrech!)
- removing front engine frame
- removing bracket for shiftercable
- hang off rear traction bar
- removing cat for left exhaust
- removing rear bracket for traction bar
- removing rear pipe between cat and header
- removing heatshield on rear header
- removing rear header
- O2 sensor exchanging
- wrap in rear header with heat-bandage
- mounting rear Taitec header
- mounting pipe between header and kat (rear section)
- extending wire harness for O2 sensor
- removing pipe between header and kat at front header section

about 4 hours work


I have to do this tomorrow:
- removing heat shield on front header
- looening a/c compressor and hang it off abit
- removing front header
- O2 sensor exchanging
- wrap in rear header with heat-bandage
- mounting front Taitec header
- mounting pipe between cat and header (front section)
- extending wire harness for O2 sensor
- mounting cat for left exhaust
- mounting rear traction bar
- mounting bracket for traction bar
- mounting front engine frame
- mounting engine mount
- mounting bracket for shift-cable

I guess another 5 hours of work.

I needed about 9 hours total for the first time. I heard story of people doing all this in 3 hours.....is this a joke?. Only for the wraping I needed about 2 hours....those are 6 pipes with about 50cm each. I think w/o wraping it needs 5-6 hours to change out the headers, but only when you do not have troubles with old rusty exhaust bolts.

The rear engine frame is of aluminium too, damn it weight maybe only 2 kilos.

The oem header looks realy tiny compared to the nice Taitec one

http://www.voehr.com/upload/auto//taitec_on_NSX_3.jpg__scaled_800.jpg

http://www.voehr.com/upload/auto//taitec_on_NSX_4.jpg__scaled_800.jpg

http://www.voehr.com/upload/auto//taitec_on_NSX_5.jpg__scaled_800.jpg

http://www.voehr.com/upload/auto//taitec_on_NSX_6.jpg__scaled_800.jpg

http://www.voehr.com/upload/auto//taitec_on_NSX_7.jpg__scaled_800.jpg



here is the Dyno report quoted from nsxprime!

Today I was on the dyno with my NSX. When I was last year I had exact 280hp (274hp in the papers of euro NSX 1991 models). That means 6hp over stock :)

During winter time I installed the Taitec GT light weight exhaust and the Taitec header system. Thanks to Chris @ SoS at that point. He does always a great service to me.

When we did the fist run we got a little wheel spin and 298hp. A friend and I was sitting down into the trunck when the dyno-guy started the 2nd run. 303hp with out any wheel spin.

Test was made in 5th gear. There is no difference if testing in 4th or 5th gear like some people are saying. Check out my last Dynorun where I tested that out.

My goal was to reach more than 300hp, and I did it :)


Taitec claims an hp gain of 22.6whp, thats about 25hp to the fly. I had gained 23hp at the fly, so I am a happy Taitec user.

The tourqe also went up from 291 Newtonmeter to 312 Nm!

Sound is realy awesome. It is not that loud in the cabine and you can talk just normaly. There is also no bad Sound on lower rpm like some people do say. When my friend did a test drive on a road so I could listening to the sound, I was F$%K thats loud! Not a bad loud sounding, but a NICE loud sound! ;) I hope the cops are thinking that too :P


here is a link to the dynorun (works with Quicktime), 2,62mb!
http://www.voehr.com/upload/store/vid1.mov


http://www.voehr.com/upload/auto//kw_nm.jpg__scaled_682.jpg

http://www.voehr.com/upload/auto//kw_kmh.jpg__scaled_721.jpg





the old dyno sheet with stock parts

http://www.voehr.com/upload/auto//dyno_280ps.jpg__scaled_889.jpg


compare 4the vs 5th gear when the car was stock:
http://www.voehr.com/upload/auto//dyno_4th_vs_5th_2.jpg__scaled_791.jpg

[ctrlaltdelboy]

Hi Christian

welcome to our forum, and thanks for what must be the most comprehensive first post ever received!

good stuff ;)

[Rob_Fenn]

That is an awesome gain...

Welcome :D

[markc]

Nice work Christian, good to see someone else not scared to work on their NSX. :P

Your car looks very clean underneath for its age and mileage. Either your car has only seen fair weather use or you use something more sophisticated that salt on icy roads in Austria.

Doing power runs in more than one gear is a good way to check the flywheel figures are acurate. The Dyno, more acurately a rolling road dyno, actually measures the power at the wheels. As I understand it power at the flywheel is calculated by measuring the power taken to drive the engine/transmission under no load ie freewheeling. From this you can calculate transmission loss. Comparing runs in 2 gears should, in theory, result in the same flywheel power (like yours), if it doesn't the RR dyno needs recalibrating.

Some people only like to talk about power at the wheels figures but at least accurately calculated flywheel figures let you compare back to the manufacturers claims.

Cheers

Mark

[austrian type-r]

hehe, it seems there is a person who understand the measurment with an Bosh Dyno. US-people often don't get it. In my opinion by just measuring the whp you can not realy tell how much hp the car realy have.

[markc]

I suppose ultimately they're (the US guys) correct in that only the power reaching the road is relevent BUT that's not what manufacturers quote so flywheel figures are IMHO much more interesting. :)

A properly maintanied and calibrated rolling road dyno WILL give you acurate flywheel horsepower figures. (extracted from the measured wheel horsepower).

Shame it's not practical to remove the engine and hook it up to a proper brake dynomometer.... might be fun tho' :shock:

Mark

[Papalazarou]

I was reading the Honda-Rev's rolling road shootout in J-Tuner the other day and I was amazed by the 'supposed' transmission losses on the cars being tested; mostly Integra's, Civic's form memory.

Especially considering my assumption (rightly or wrongly) that *** stuff tends to lose less than most.

James.

[ctrlaltdelboy]

the issue with using flywheel figures is that despite the attraction of having a figure that you can compare directly with those quoted/claimed by manufacturers, there is too much inaccuracy/inconsistency/exaggeration in the figures measured at the wheels being calculated back to the flywheel.

this leaves us with a whole bunch of claimed figures which we cannot trust to be correct.

the problem is exascerbated by the very fact that higher figures are more desirable, giving rise to the temptation to exaggerate the assumed transmission losses etc.

even to the extent where on a shoot-out session where the operator may be more conservative in the calculations, the attending club members may go away somewhat disappointed, then when discussing figures later hear of another RR which had higher power results from similar cars, leading to the next shoot-out being held at the other RR, where the operator is using different calcs designed to deliver inflated flywheel figures thereby getting satisfied customers.

the upshot is that the RR delivering more realistic results loses business while the RR tweaking the numbers to deliver falsely high results gets satisfied customers, rave reviews and repeat business.

all of this is very wrong, and my own conclusion is to simply stick to figures measured at the wheels for any kind of meaningful comparison.

[markc]

Darren, with respect I think you're missing my point slightly...

Remember the RR dyno will give you RWHP if you want it, that's what it's actually measuring after all.
I can't see this (RWHP or RWKW) on Christian's readouts/graphs but it must be possible, maybe an option in the software?

The "run down" (freewheel) after the power run measures the actual transmission loss. This is then used to calculate FWHP.

The problem comes if you use an assumed rather than measured transmission loss. If you do this then the "calculated" FWHP is unreliable.

I too have heard of widely differing figures from 1 RR to another and perhaps some RR operators are allowed to enter (key in) a transmission loss figure rather than using a measured one? :roll:
Also, remember atmospheric conditions may have varied to effect the measured power.

I guess the smart thing is to make sure you get both power readings (RW & FW) AND ensure atmospheric conditions are simlar before making any definitive claims for improved power.

Mark

[ctrlaltdelboy]

not missing your point Mark- just contributing ;)

as you said above, using more than one gear to ensure consistency in assumed/calculated transmission losses and thereby getting the calculated flywheel figure as accurate as possible is all good and noble stuff, but sadly I feel rather absent from most RR's, especially on shoot-out days.

when it comes time to print the results, there are various options which can be selected to appear - the choice between 'measured at the wheels' or 'estimated at the flywheel' figures would be taken by the operator (usually according to the client's preference) and the printout would represent this choice.

I do agree with you Mark, that in a perfect world we would all be comparing properly estimated flywheel power figures; BUT we do not live in a perfect world, so in this one, I put more stock in results showing measured power than estimated power, as I usually have no way of knowing the methods used to acheive the estimate on any given dyno chart that I see, whereas measured figures have much more consistency and comparability.

[austrian type-r]

The Dyno I was and his Software must be very accuarte, cause when my car was 100% stock I had 280 hp to the engine - about the same what the manufacter claims.

A Dyno is just a tool, use always the same Dyno and make always a before and after testrun, so you can see how much the modification you did adds hp.

[markc]

I've got this RR plot from one of my old Porsche 993 cronies....

The plot has both RWHP and FWHP and shows the transmission loss, so it can be done. 8)

I'll try and work out who's it was and where it was done. Nice result from a 993 tho', must have been tweeked. :)

Mark

[Papalazarou]

Hi Christian,

just curious, but what's it like on the road with the extra power? Do you notice a difference?

Cheers,

James.

[austrian type-r]

Thats realy hard to tell, since I have not driven the NSX for about 6 month between before and after the modification. But for sure I can tell it revs up faster to the red line. With stock header and exhaust the last few hundred revs was a bit slower rising up to the cut. The engine is feeling more "free" now.

[Papalazarou]

I've just fitted a new silencer and was surprised to feel slightly better bottom end torque. From what I have heard it's unusual to get any power gains until you do the manifolds too.
It may just be in my mind though, not being used to the different noise at those revs.

James.

[kowalski]

Have to say you can do this mod with just axle stands, as I just did it :)

Not the ideal way of doing things but not too bad a job access wise, Front manifold is a bit tricky, especially if the O2 sensor wont come out in situ.

Thanks to Dirk for the O2 sensor advice, had a good tip about dismantling the sensor connector to allow you to get a ring spanner over it.

Great improvement in Noise, Power & torque!

leigh