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NoelWatson
08-04-2008, 07:17 PM
After Saturday's dyno day, it became apparent that the NSX would appear to be receptive to tuning. There were a number of us there that expressed an interest in improving our power outputs. It would be good if we can use this thread to


Discuss various mods. For example, which is the best exhaust if we are looking for maximum power gains
Post findings on power gains after modifications so other owners can improve performance with the minimum of fuss
There may be opportunities for discounts if we can get enough people for a group buy
If people are interested we can get the mods done to cars at the same time meaning that we can get a group together to revist TDI in a few months time

NoelWatson
08-04-2008, 07:20 PM
So to kick things off, here is where I stand.

I am keen to get a new exhaust. Taitec has been mentioned, but I understand there is more than one flavour? Should I be going for an H&S instead as it gave good results on Sat? Any other alternatives? Have we got any dyno results for the Procar intake? I can't really go for the throttle bodies as my car is under warranty. Not sure about removing cats as it may get a bit noisy.

NoelWatson
08-04-2008, 07:29 PM
There are some dyno runs here

http://www.scienceofspeed.com/products/exhaust_airflow_products/NSX/TAITEC/JGTC_Center_Exhaust/

http://www.scienceofspeed.com/sos_resource/FAQs/NSX/eap/exhaust_comparison/default.asp

Senninha
08-04-2008, 08:54 PM
Should I be going for an H&S instead as it gave good results on Sat?

It get my vote and has consistently outperformed others in b2b tests :)


Have we got any dyno results for the Procar intake?

Here is the response I received from Detlef ref his Procar airbox



Hi Paul,

Here is my experience with the bottleneck.
(Ive modified mine and Honda NSX-R racecar units)

For engine power upgrade ist really important to optimize the poorly designed standard air intake.
That happened with my fender scoop and the airbox, the Honda guys dynoed +12 HP more at the NSX-R w/o the modified TB.

Beside this air intake the size of the throttle body concludes the air quantity, which will be aspirated from the engine. The main difference is to enlarge that part per directed milling.

The most throttle bodies are modified only at the airfilter side, the throttle body which I have at my car and at the race cars have additional milling at the engine side plus valve enlargement. (larger diameter and some secret details)
The result is a better throttle response and more power.

But its lot of work to make it perfect....and do cost
money.

Regards
Detlef

regards, Paul

Senninha
08-04-2008, 08:56 PM
And to keep all the info together I've copied this post from the TDI thead

Recieved this info from Chris at SOS today

http://www.scienceofspeed.com/produc...rottle%5Fbody/ (http://www.scienceofspeed.com/products/exhaust%5Fairflow%5Fproducts/NSX/ScienceofSpeed/big%5Fbore%5Fthrottle%5Fbody/)


hi Paul --
I would agree, any throttle body will not have a zero pressure loss in restriction. The throttle body we offer is both larger and has a throttle blade and fasteners that are less restrictive (you can find photos on our website). We have tested the throttles and have found that the throttles add around 3-4 hp on NA cars and up to 9 hp on superchargered cars.
Hope that helps.

In addition, I spoke to PLans today to see if they had ever been involved in this type of activity with the NSX. The short answer is no. However, they have done this on a number of occasions for the Elise. 2 things they mentioned to be wary off.

1. Ensure that where applicable, the TB's are for the drive by wire system (later 3.2's)
2. That the ECU would be able to accomodate the change. On the Elise they go up by 4mm. Any more than this and the ECU gets confused, more so at low revs when opening the throttle. It is not uncommon for this action to then put the car into limp home mode.

Jim,

Let us know what Mark (Dali) has to say



If it's just boring and a larger butterfly then can't we get this done in the UK ??

I'm also wondering if we could find a spare TB for the 3.0 and 3.2 , could there may be a deal to be done with TDI on a rolling exchange from one car to another??

regards, Paul

BlueNSX
08-04-2008, 09:18 PM
So with the previous information where does that leave us? - if the guys at SOS are correct its "plug and play", they obviously have done the testing so we shouldnt suffer the problems that Plans discussed with the Elise.

Can we find out what Detlef wants to charge for his conversion, but from his comments its going to be ££££. Can we get dyno proof on his Airbox

Do we Bite the bullet and buy from SOS?

I am going to Dyno my car once serviced.

Senninha
08-04-2008, 09:39 PM
Taken from Dali website



A new throttle plate is installed and the throttle body bore is tapered, enlarged and polished to fit. Each throttle body is bead blasted for perfect appearance and the TPS sensor is reset for optimum performance.


Gents,

Whilst I think we could find someone to do the engineering work of enlarging and polishing, how do we stand on finding someone to attend to the highlighted issue?

Noel, is this something you would have knowledge about?

regards, Paul

britlude
08-04-2008, 09:53 PM
my recommendation... topspeed headers, cant beat them for value for money....

http://nsxcb.co.uk.sites.imotionhosting.com/testvb/attachment.php?attachmentid=2706&d=1189247395


currently stupid cheap on prime.... still listed on ebay!

http://www.nsxprime.com/forums/showthread.php?t=102427&highlight=topspeed

AR
08-04-2008, 09:54 PM
The exhaust is simple. One with the least amount of backpressure. IMHO All Stainless steel exhaust that offer that will drone at certain RPMS. The H&S looks like a copy of this:

http://www.scienceofspeed.com/products/exhaust_airflow_products/NSX/TAITEC/GT_Lightweight_Exhaust/

I don't particularly like the design, if I was shopping for an exhaust for a 3.2 you can't find a better deal than this since GT-Rom is gone:

http://www.scienceofspeed.com/products/exhaust_airflow_products/NSX/ARK/DT-S/

I had the ARK before and it was Zero drone and great response whilst not too loud.

My current Exhaust is the same as the one Vance has in his NSX-R replica on Prime and his is way over 300.

On the intake side I do not feel that the Procar or any other box is so much better than OEM. I had a Procar box and it was Huge, had a rechargeable filter, that would concern me.

There is no way that just an Airbox gives you 12 BHP on an NSX.

The Gruppe M on the other hand was too loud when I had the NSX-R.

If I was in the market I would get a Mugen one, but they are way too pricey for what they are.

Paul's, Mark's are cars that are run in and have some mods, just look how little difference there was between them less than 1 bhp. What is common about them...Non OEM less restrictive exhaust!

Barry achieved great numbers ( 293.4 ) with my exhaust and Airbox mod all I did was inspire myself by what others have done over the years.


Cheers,

AR

BlueNSX
08-04-2008, 10:28 PM
My current Exhaust is the same as the one Vance has in his NSX-R replica on Prime and his is way over 300.

What Exhaust do you have ?

On the intake side I do not feel that the Procar or any other box is so much better than OEM. I had a Procar box and it was Huge, had a rechargeable filter, that would concern me.

This is what I have purchased from Dali, please let me know your thoughts

3520

There is no way that just an Airbox gives you 12 BHP on an NSX.

I would agree thats very philosophical - a product plug ?

The Gruppe M on the other hand was too loud when I had the NSX-R.

If I was in the market I would get a Mugen one, but they are way too pricey for what they are.

Which Mugen one?

Paul's, Mark's are cars that are run in and have some mods, just look how little difference there was between them less than 1 bhp. What is common about them...Non OEM less restrictive exhaust!

Barry achieved great numbers ( 293.4 ) with my exhaust and Airbox mod all I did was inspire myself by what others have done over the years.

Ary, what would your suggestion be for those that have 3.0 non type -R
to get the same performance?

Taitech Headers -
Intake of some Sort -
Throttle Body -
ECU - Remap or Programmable
Titanium Valve springs -
Cams -


Cheers,

Blu

kowalski
08-04-2008, 11:51 PM
I think after Saturday I will definitely be ordering the Throttle Body from SOS, and also look into a remap to solve mine running lean. I am away on a flying trip at the moment so hopefully will place an order next week when i can get my throttle body off to send away.

when ive done the mods I will take it back to TDI to get a good comparison.

leigh

NoelWatson
09-04-2008, 04:54 AM
The exhaust is simple. One with the least amount of backpressure. IMHO All Stainless steel exhaust that offer that will drone at certain RPMS. The H&S looks like a copy of this:

http://www.scienceofspeed.com/products/exhaust_airflow_products/NSX/TAITEC/GT_Lightweight_Exhaust/

I don't particularly like the design, if I was shopping for an exhaust for a 3.2 you can't find a better deal than this since GT-Rom is gone:

http://www.scienceofspeed.com/products/exhaust_airflow_products/NSX/ARK/DT-S/

I had the ARK before and it was Zero drone and great response whilst not too loud.

My current Exhaust is the same as the one Vance has in his NSX-R replica on Prime and his is way over 300.

On the intake side I do not feel that the Procar or any other box is so much better than OEM. I had a Procar box and it was Huge, had a rechargeable filter, that would concern me.

There is no way that just an Airbox gives you 12 BHP on an NSX.

The Gruppe M on the other hand was too loud when I had the NSX-R.

If I was in the market I would get a Mugen one, but they are way too pricey for what they are.

Paul's, Mark's are cars that are run in and have some mods, just look how little difference there was between them less than 1 bhp. What is common about them...Non OEM less restrictive exhaust!

Barry achieved great numbers ( 293.4 ) with my exhaust and Airbox mod all I did was inspire myself by what others have done over the years.


Cheers,

AR

AR,

While Paul's early 3.2 car got 275 ish, "other Paul" with his 2005 "only" got 267. I mentioned on the other thread that I think the 02 cars may be down on power compared to the early 3.2s - parts of the exhaust system do appear to have changed - we may have to bear this in mind when comparing results

http://www.scienceofspeed.com/products/engine_performance_products/NSX/NGK/NTK_O2_Sensors/

NoelWatson
09-04-2008, 04:55 AM
Taken from Dali website




Gents,


Whilst I think we could find someone to do the engineering work of enlarging and polishing, how do we stand on finding someone to attend to the highlighted issue?


Noel, is this something you would have knowledge about?



regards, Paul


Paul,

Unfortunately not - a lot of learning to be done from my end

NSX 2000
09-04-2008, 08:21 AM
AR,

While Paul's early 3.2 car got 275 ish, "other Paul" with his 2005 "only" got 267. I mentioned on the other thread that I think the 02 cars may be down on power compared to the early 3.2s - parts of the exhaust system do appear to have changed - we may have to bear this in mind when comparing results

http://www.scienceofspeed.com/products/engine_performance_products/NSX/NGK/NTK_O2_Sensors/

Noel, In my 2000 NSX I got 275 at Surrey RR day this is a 'calculated' figure at the flywheel. (I'm sure it was 279 at Surrey but the 275 is what Simon took down, I need to dig out the paper work.)
In my 2005 I got the 267 at TDi and this as you know is a at the wheel figure. So if you do 267 x 1.1111 then you get a 'calculated' figure at the flywheel of 296.6

Paul.

mutley
09-04-2008, 09:52 AM
I have sent an email to Dali for info, here is a link to the page on Dali site

http://www.daliracing.com/v666-5/catalog/index_browse_part.cfm?focus=1671

It also mentions about the TPS thingy and being 3.75 mm bigger than stock.

Jim

AR
09-04-2008, 09:57 AM
AR,

While Paul's early 3.2 car got 275 ish, "other Paul" with his 2005 "only" got 267. I mentioned on the other thread that I think the 02 cars may be down on power compared to the early 3.2s - parts of the exhaust system do appear to have changed - we may have to bear this in mind when comparing results

http://www.scienceofspeed.com/products/engine_performance_products/NSX/NGK/NTK_O2_Sensors/

Mate I am almost sure as are otheres that it takes some use for the NSX engine to release all of it's power.

I don't buy the exhaust theory mate, why would they make it slower???

Honda are too cheap to change the exhaust anyway!

AR
09-04-2008, 09:58 AM
my recommendation... topspeed headers, cant beat them for value for money....

http://nsxcb.co.uk.sites.imotionhosting.com/testvb/attachment.php?attachmentid=2706&d=1189247395


currently stupid cheap on prime.... still listed on ebay!

http://www.nsxprime.com/forums/showthread.php?t=102427&highlight=topspeed (http://www.nsxprime.com/forums/showthread.php?t=102427&highlight=topspeed)

You get what you pay for mate, I would not go cheaper than Taitec, but each their own.

simonprelude
09-04-2008, 10:01 AM
I don't think any direct comparisons can be made between TDI, Surrey Rolling Road and Power Engineering at Uxbridge. They all measure in different ways so will not give the same figures.

We need to decide which Rolling Road will be the NSX one of choice and stick with it :)

TDI to me seem to be the most professional, unfortunately they are also the furthest away from me :( buy I am willing to ignore that part for the good of NSX further development within the club.

AR
09-04-2008, 10:23 AM
What Exhaust do you have ?


This is what I have purchased from Dali, please let me know your thoughts

3520


Which Mugen one?

Ary, what would your suggestion be for those that have 3.0 non type -R
to get the same performance?

Taitech Headers -
Intake of some Sort -
Throttle Body -
ECU - Remap or Programmable
Titanium Valve springs -
Cams -


Cheers,

Blu

I have the GT-Rom v1 Ti Exhaust.

For the intake you can't go wrong with a fender scoop + OEM filter to stay safe or Unifilter for the extra 3-4 HP.

The Mugen I would buy is the enclosed cone type.

If you are going to be adding cams and such then I would go for a programmable ECU.

Cheers,

Ary

simonprelude
09-04-2008, 11:21 AM
What about this as well ??

http://www.scienceofspeed.com/products/exhaust%5Fairflow%5Fproducts/NSX/Cantrell%5FConcepts/AIS/ais_intake_fender_removed.jpg

http://www.scienceofspeed.com/products/exhaust%5Fairflow%5Fproducts/NSX/Cantrell%5FConcepts/AIS/

AR
09-04-2008, 02:32 PM
What about this as well ??

http://www.scienceofspeed.com/products/exhaust%5Fairflow%5Fproducts/NSX/Cantrell%5FConcepts/AIS/ais_intake_fender_removed.jpg

http://www.scienceofspeed.com/products/exhaust%5Fairflow%5Fproducts/NSX/Cantrell%5FConcepts/AIS/

That is the fender scoop I was talking about Simon. :)

markc
09-04-2008, 04:56 PM
I don't think any direct comparisons can be made between TDI, Surrey Rolling Road and Power Engineering at Uxbridge. They all measure in different ways so will not give the same figures.

We need to decide which Rolling Road will be the NSX one of choice and stick with it :)

TDI to me seem to be the most professional, unfortunately they are also the furthest away from me :( buy I am willing to ignore that part for the good of NSX further development within the club.

Guys, here's an attempt to allow us to compare the the 3 dyno facilities used... See attached spreadsheet

The assumptions were...
The Rototest kit (at TDI) produces the most acurate results.
Rototest say "on average" comparisons between their at the hub measurement and the manufacturers at the flywheel claims are 10%, hence the 1.1 upscale suggestion. I used 9% or 1.09 to err on the conservative side.
I used Paul's (Senninah) car as the link to the 2006 Power Engineering day the applied the same conversion ratios to the other cars present on that day.
I used Noel's (NoelWatson) car as the link to the 2008 SRR day and applied the same conversion ratios to the cars present that day.

Observations...
The unmodified 3.2Ltr cars of SimonPrelude (Simon), Lankstarr (Luke), Boomin33 () TheQuietOne (Matt) and NSX 2000 (Paul with W2) are remarkably similar! BHP varies just 7bhp and torque by just 5ft/lbs. If you exclude the largest single variable for each, it drops to just 4bhp and 2ft/lbs!!!
The unmodified 3.0Ltr cars are also pretty close.

The 3.2Ltr crs fitted with aftermarket exhausts and/or airboxes made approx 15hp and 7-8ft/lbs.
The 3.0Ltr cars fitted with aftermarkets manifolds(headers), exhausts and/or airboxes made 25-30hp and 10ft/lbs

The results from the 2006 Power Engineering day would appear to be a bit low.
The SRR day gave fractionally high results.

What have we proved...
Confirmation that exhaust and headers help pretty significantly.
Inlet/airbox modifications may help. More tests needed.
Possible other inlet restriction (throttle body) to be investigated.

Mark

NoelWatson
09-04-2008, 06:11 PM
Guys, here's an attempt to allow us to compare the the 3 dyno facilities used... See attached spreadsheet

The assumptions were...
The Rototest kit (at TDI) produces the most acurate results.
Rototest say "on average" comparisons between their at the hub measurement and the manufacturers at the flywheel claims are 10%, hence the 1.1 upscale suggestion. I used 9% or 1.09 to err on the conservative side.
I used Paul's (Senninah) car as the link to the 2006 Power Engineering day the applied the same conversion ratios to the other cars present on that day.
I used Noel's (NoelWatson) car as the link to the 2008 SRR day and applied the same conversion ratios to the cars present that day.

Observations...
The unmodified 3.2Ltr cars of SimonPrelude (Simon), Lankstarr (Luke), Boomin33 () TheQuietOne (Matt) and NSX 2000 (Paul with W2) are remarkably similar! BHP varies just 7bhp and torque by just 5ft/lbs. If you exclude the largest single variable for each, it drops to just 4bhp and 2ft/lbs!!!
The unmodified 3.0Ltr cars are also pretty close.

The 3.2Ltr crs fitted with aftermarket exhausts and/or airboxes made approx 15hp and 7-8ft/lbs.
The 3.0Ltr cars fitted with aftermarkets manifolds(headers), exhausts and/or airboxes made 25-30hp and 10ft/lbs

The results from the 2006 Power Engineering day would appear to be a bit low.
The SRR day gave fractionally high results.

What have we proved...
Confirmation that exhaust and headers help pretty significantly.
Inlet/airbox modifications may help. More tests needed.
Possible other inlet restriction (throttle body) to be investigated.

Mark

Sums it up perfectly!

NoelWatson
09-04-2008, 08:02 PM
Science of Speed listing stages of modifications

http://www.scienceofspeed.com/products/engine_performance_products/NSX/ScienceofSpeed/NA_power_stages/

I think Stage 1 is my limit

NoelWatson
09-04-2008, 08:06 PM
What about this as well ??

http://www.scienceofspeed.com/products/exhaust%5Fairflow%5Fproducts/NSX/Cantrell%5FConcepts/AIS/ais_intake_fender_removed.jpg

http://www.scienceofspeed.com/products/exhaust%5Fairflow%5Fproducts/NSX/Cantrell%5FConcepts/AIS/


They claim 6.9 bhp for this, but say it shouldn't be used in heavy rain!! If Marc gets this, his "high compression" Type S may well take the lead.

Senninha
09-04-2008, 08:51 PM
What about this as well ??

This is also part of the Procar set-up. The theory is that it will induce a ram air effect for the larger capacity airbox.

As for driving in the rain its simple, just slow down! I've been out in very heavy rainful without a problem, Even crossed througha ford without issue.

reg
09-04-2008, 09:06 PM
My .02

I/H/E give gains. Obviously any production manufacturer has to honour silly regs rather than make an engine more driveable.

If I had my time again I would get the head flowed and change cams. Yes you will see gains from induction systems but they are variable and more importantly the gains might only be apparent in a certain rpm range. More fuel/air mixture is great, however you need to be able to burn it. I dont know how optimised the NSX's cams are or what sort of valve area is possible but I am sure SOS does.

Give them a call, bigger valves and more aggresive cams would be my call.

Senninha
09-04-2008, 09:40 PM
If anyone is interested in stating th ball rolling, Dirk has both versions of the TB available. So, if we could find an engineering centre, or maybe TDI can do the work?, these could be bought and modified before installation.

The ones removed could then be upgraded and swapped onto the next NSX etc.

I'm sure that as Reg suggests, valves/cams etc would yeild yet more power, but for me, the work has to remain outside of the main engine unit, particular as mine appears to be a good one!!

HTH, Paul

AR
09-04-2008, 10:17 PM
They claim 6.9 bhp for this, but say it shouldn't be used in heavy rain!! If Marc gets this, his "high compression" Type S may well take the lead.

They have to say that as it is in America and if some fool buys it and decides to use his NSX as a boat they want to be cover for hydroloc. I have had two of them and no problems yet.

Cheers,

AR

reg
09-04-2008, 10:46 PM
If anyone is interested in stating th ball rolling, Dirk has both versions of the TB available. So, if we could find an engineering centre, or maybe TDI can do the work?, these could be bought and modified before installation.

The ones removed could then be upgraded and swapped onto the next NSX etc.

I'm sure that as Reg suggests, valves/cams etc would yeild yet more power, but for me, the work has to remain outside of the main engine unit, particular as mine appears to be a good one!!

HTH, Paul

Paul,

If anyone here has a TB that they want boring then I can do it. I have bored carb's for race bikes (tapered bells) and have lots of experience with one off machining. I can also draw the TB before and after so it can be re-manufactured or cast.

The issue is how big do you open TB's before the heads wont flow the increased mixture. As for internal work, I agree it is always squeaky bum time when you start to talk about cams and irreversable porting BUT there is a limit to what a bunch of bolt ons can do without the ability to burn the mixture and map the ignition/injectors.

You really need a cheap NSX as a mule as resale wil suffer no matter what gains you achieve with serious mods. I just know there is no point faffing about and money is better spent, has anyone here ever heard/seen a ported NSX with big valves?

Senninha
10-04-2008, 10:42 AM
Guys, here's an attempt to allow us to compare the the 3 dyno facilities used... See attached spreadsheet

I used Paul's (Senninah) car as the link to the 2006 Power Engineering day the applied the same conversion ratios to the other cars present on that day.
Mark

So I missed 300 by 1bhp :angry: Would youcare to revisit your spreadsheet, maybe you've rounded down instead of up :laugh:

regards, Paul

AR
10-04-2008, 10:56 AM
If anyone is interested in stating th ball rolling, Dirk has both versions of the TB available. So, if we could find an engineering centre, or maybe TDI can do the work?, these could be bought and modified before installation.

The ones removed could then be upgraded and swapped onto the next NSX etc.

I'm sure that as Reg suggests, valves/cams etc would yeild yet more power, but for me, the work has to remain outside of the main engine unit, particular as mine appears to be a good one!!

HTH, Paul

Paul have a read here:

http://www.nsxprime.com/forums/showthread.php?t=56281&highlight=obit

I am sure if you get test pipes you will break the 300 hp barrrier and V-max!

markc
10-04-2008, 04:19 PM
I'm with you Paul in not wishing to open up the motor at this time.

I'll be pursuing the inlet trumpet thingy, airbox and throttle body as well.

Sorry, I did indeed round to the nearest whole number (down for less than 0.5 and up for more than 0.5) and also set the spreadsheet cell format to round to nearest whole number. Use 1.1 as the upscale and we can both have 301bhp :)

Reg, can you get a larger throttle plate/butterfly fitted as well? The version sold by Science of Speed has this and also recalibrates the TPS (throttle Position Sensor) presumably just for closed and wide open positions?

They (SOS) also cater for 4 distinct versions 1991-1995, 1996-1996, 1997-1999, 2000-2005.
I know the first one is for the non DBW (Drive By Wire) cars. But I wonder what the differance is between the other 3? I also know that the 2000 cars got a revised DBW program. I would have thought the TPSs are the same and the DBW program is in ECU but maybe not.

Mark

Senninha
10-04-2008, 04:46 PM
Thank you kind Sir :)

reg
11-04-2008, 08:45 AM
Reg, can you get a larger throttle plate/butterfly fitted as well? The version sold by Science of Speed has this and also recalibrates the TPS (throttle Position Sensor) presumably just for closed and wide open positions?

They (SOS) also cater for 4 distinct versions 1991-1995, 1996-1996, 1997-1999, 2000-2005.
I know the first one is for the non DBW (Drive By Wire) cars. But I wonder what the differance is between the other 3? I also know that the 2000 cars got a revised DBW program. I would have thought the TPSs are the same and the DBW program is in ECU but maybe not.

Mark

Hi Mark,

If it is 'just' following the factory taper at +5mm then matching everything I would have a go. I cant say for the NSX but generally when you set up a throttle pot its at zero and max.

SOS are doing this fairly cheaply by the look of it, it would be interesting to see what they do as that doesn't leave much scope to mess around with the butterfly etc? Could they have a butterfly from something else as a bolt on?

NoelWatson
13-04-2008, 12:27 PM
Mod details from TDI website

http://www.tdi-plc.com/catalog/index.php?cPath=107_108_347_566

I think we would fail noise at Bruntingthorpe if we removed the cats

Senninha
13-04-2008, 12:48 PM
Mod details from TDI website

http://www.tdi-plc.com/catalog/index.php?cPath=107_108_347_566

I think we would fail noise at Bruntingthorpe if we removed the cats

But these probably wouldn't and might release a few ponies :dunno:

http://www.scienceofspeed.com/products/exhaust_airflow_products/NSX/Random_Technology/high-flow_cat_converters/

NoelWatson
13-04-2008, 01:19 PM
But these probably wouldn't and might release a few ponies :dunno:

http://www.scienceofspeed.com/products/exhaust_airflow_products/NSX/Random_Technology/high-flow_cat_converters/

It says 1991 - 1994 - I wonder if they do them for our versions

Senninha
13-04-2008, 01:37 PM
It says 1991 - 1994 - I wonder if they do them for our versions

Thye do but are special order and at same price. SOS receommend using them with Cantrell headers for best bhp gains