anyone intalled NHP full exhaust???

[Jake Raby]

The average HP I see from any Boxster S is 223, average TQ is 210.

[2K3_Boxster_S]

Originally Posted by Adam

183 hp and 177ft/lb at the wheels? Something is definately wrong with the car or the way it was dynoed. This 2003 S at fabspeed dynoed 229 hp and 203 ft/lbs at the wheels...bone stock.

http://www.fabspeed.com/Boxster.html

Not saying that your wrong, but what kind of dyno? every dyno is not the same. this is on a Dynapack the owner said it is very stingy. here is a video of a guy that dynoed right after me. It's a ford merkur (iron block) on 25 psi to 30 psi (boost creep) and he is used to seeing well into the 300 whp. Well, he didn't even get close. I'm just saying every dyno is and will be different. i'm considering re-dynoing somewhere else. maybe the way it was set up or just this dyno. the car is definitely not driving like 183 and 177.

this car makes well over 300. not on this dyno.

http://s80.photobucket.com/player.swf?file=http://vid80.photobucket.com/albums/j179/ryancausey/M2U00194.flv&fs=1&os=1&ap=1

[Jake Raby]

Your engine is rated at over 250 flywheel HP.. If his dyno is that stingy, it's inaccurate. These engines generally lose a max of 15% to the drive train as RWHP.

Find a dynojet, the numbers from unit to unit are near exacyting and the industry standards are set on dynojet units.. Thats why I bought one instead of a dyna pack..

I have engines tested in either of my engine dyno labs, install them into the car and generally see a 13-15% difference from flywheel HP to RWHP consistently.. Thats how I know our numbers are spot on.

[2K3_Boxster_S]

Originally Posted by Jake Raby

Your engine is rated at over 250 flywheel HP.. If his dyno is that stingy, it's inaccurate. These engines generally lose a max of 15% to the drive train as RWHP.

Find a dynojet, the numbers from unit to unit are near exacyting and the industry standards are set on dynojet units.. Thats why I bought one instead of a dyna pack..

I have engines tested in either of my engine dyno labs, install them into the car and generally see a 13-15% difference from flywheel HP to RWHP consistently.. Thats how I know our numbers are spot on.

yes, i think its kind of strange the guy that dynoed right after me was around 40 hp under what he is used to seeing. that would put me exactly on the average you said you see for an S. 223 hp. i'll look for a dynojet.

thanks

[Adam]

Originally Posted by 2K3_Boxster_S

yes, i think its kind of strange the guy that dynoed right after me was around 40 hp under what he is used to seeing. that would put me exactly on the average you said you see for an S. 223 hp. i'll look for a dynojet.

thanks

I would....there is usually just a 1-3% difference between dynoes so there is something else going on. I've heard the dynapac's are stingy, but your hp #'s are similar to what early 2.7L engines put out, not even close to 03 S power. The huge drop in the middle of your torque curve is very strange as well. The TQ curve should be nearly flat.

[2K3_Boxster_S]

update:

Going to change the plugs and re-dyno on a dynopac (roller dyno). will also have AFR's this time as well.

Hope I can get it in before 7/19. out for work after that.

Later

[Jake Raby]

Cool.. I consider the AFR data more important during this evaluation than the HP output... But then again, I average HP numbers before I even look at peak numbers, because peak is so very worthless unless you drive around at above 5,252 RPM ALL THE TIME.

[2K3_Boxster_S]

Originally Posted by Jake Raby

Cool.. I consider the AFR data more important during this evaluation than the HP output... But then again, I average HP numbers before I even look at peak numbers, because peak is so very worthless unless you drive around at above 5,252 RPM ALL THE TIME.

Porsche has had my car since Monday (AC service) I get home from work today (Friday) "hey your car's ready". Not sure if I can get this done before 7/19. If not it's going to be another month. (out of town again, for work). I could just bolt up the exhaust, but I want to do this the right way. and from what every one has said about the Dyno sheets, something doesn't look right. which is why I insist on re-dynoing it.

This could take awhile. oh well,

[2K3_Boxster_S]

Ok, It didn't get done. I'm out of town again. return Aug. 15. It will be dyno'ed upon return on a roller dyno with AFR readings. Then NHP exhaust will then be installed and re-dynoed on same dyno. Sorry for the wait. But I feel an accurate baseline is needed so we can know what effects of the NHP setup is going to give us. Please hang in there. THANKS

here is a quote from the person who dynoed right after my on the same dyno:

"Yeah I thought yours seemed a little low even for a stocker.. but as they said that dyno is stingy. Dunno, mine dyno'd 90hp and 50ftlb down from last time.. but .. different style dyno, different conditions"

So yeah I'm gonna find a different dyno.

later

[2K3_Boxster_S]

Following has been installed:

5w-40 Castrol Syn

6 new Interpulse Plugs

NHP Full Exhaust installed

I can not tell specifically from driving on HP gains. I can say the back end broke loose like it never has before.

To me the sound is fine. if it gets to lound in the cabin all you have to do is go up a gear and it instantly quiets down to nothing. this is acceptable for me. but I also don't us the radio much.

try to dyno next weekend.

Old Beru Plugs

[cnavarro]

Long term update - probably a solid 8,000 mi on a full NHP exhaust on our '99 with sport cats. Cats started throwing a CEL about 2,000 mi and had to add o2 sensor extensions to fix the CEL. After the last track weekend, there's a rattle somewhere in the tip or mufflers, looks like their heat shield is coming loose.

[BYprodriver]

Originally Posted by cnavarro

Long term update - probably a solid 8,000 mi on a full NHP exhaust on our '99 with sport cats. Cats started throwing a CEL about 2,000 mi and had to add o2 sensor extensions to fix the CEL. After the last track weekend, there's a rattle somewhere in the tip or mufflers, looks like their heat shield is coming loose.

Did you buy the O2 sensor extensions? or did you make them yourself?

[cnavarro]

I could have made them, but I was lazy and just ordered them from FVD.

Did a quick search on google just now, there are cheaper options. Here's one I found:

http://www.tuneralley.com/megan-racing-mechanical-o2-sensor-extension-p-73047.html

[2K3_Boxster_S]

Originally Posted by cnavarro

Long term update - probably a solid 8,000 mi on a full NHP exhaust on our '99 with sport cats. Cats started throwing a CEL about 2,000 mi and had to add o2 sensor extensions to fix the CEL. After the last track weekend, there's a rattle somewhere in the tip or mufflers, looks like their heat shield is coming loose.

are the headers on the 99 the same as an 03? do you have 4 02's?

[2K3_Boxster_S]

NHP exhaust is fully bolted up.

Headers with sport cats, bypass mids, Exhaust.

Bolted up and fit perfectly. no leaks from headers or mids.

All four muffler clamps that connect the U pieces from the Mids to the rear exhaust LEAK!. THERE SUPPLIED CLAMP IS GARBAGE, and you re-use 2 of the OEM sleeve clamps which also leak. $2k the exhaust should not leak anywhere.

Next: they guarantee no CELS because all 4 O2's are reconnected. Wrong, after about 100 miles. now throwing a CEL, going to check it tommorow OBII scanner. almost sure it is going to say O2. will see.

Can't wait to here there explantion for the exhaust leaks. Gd dmn ridiculous.

Trying for DYNO with AFRS this FRIDAY. DPT tuning Chesapeake, VA.

[Boxtaboy]

Originally Posted by 2K3_Boxster_S

NHP exhaust is fully bolted up.

Headers with sport cats, bypass mids, Exhaust.

Bolted up and fit perfectly. no leaks from headers or mids.

All four muffler clamps that connect the U pieces from the Mids to the rear exhaust LEAK!. THERE SUPPLIED CLAMP IS GARBAGE, and you re-use 2 of the OEM sleeve clamps which also leak. $2k the exhaust should not leak anywhere.

Next: they guarantee no CELS because all 4 O2's are reconnected. Wrong, after about 100 miles. now throwing a CEL, going to check it tommorow OBII scanner. almost sure it is going to say O2. will see.

Can't wait to here there explantion for the exhaust leaks. Gd dmn ridiculous.

Trying for DYNO with AFRS this FRIDAY. DPT tuning Chesapeake, VA.

Just a thought- can you reuse the factory u-pipes and clamps? That way, you could at least guarantee no leak. Maybe the aftermarket u-pipe diameter is a little bit smaller than OEM, which causes the leak?

[ddb]

Originally Posted by 2K3_Boxster_S

NHP exhaust is fully bolted up.

All four muffler clamps that connect the U pieces from the Mids to the rear exhaust LEAK!. THERE SUPPLIED CLAMP IS GARBAGE, and you re-use 2 of the OEM sleeve clamps which also leak. $2k the exhaust should not leak anywhere.

Next: they guarantee no CELS because all 4 O2's are reconnected. Wrong, after about 100 miles. now throwing a CEL, going to check it tommorow OBII scanner. almost sure it is going to say O2. will see.

2K3_Boxster_S:

I just recently bolted up the same system on my 2.7. Since the only parts to be reused were the double sleeve clamps, and mine tightened/loosened like crap a couple of years ago when I put on my first aftermarket muffler, I opted to install new ones. They are part # 996-111-110-01 that list for $32.50 and I was charged $22.24 by my local dealer. Do your double clamps have the wedges in them? Did you remove them? My new clamps didn't have them installed but the old clamps did I believe. Removing the wedges allows the clamps to be torqued down tighter and is in the instructions for the mid-pipe installation.

I did use the clamps NHP supplied from the U-pipe to the muffler. Again, I removed the wedges in the clamps and torqued them really tightly. I don't believe the instructions mention removing the wedges on these clamps but I did so anyway.

I've driven my car ~ 220 miles (including 70 miles this morning) and thus far no leaks and no CEL. I hope my luck continues.

I hope you get your problems sorted soon and I like many other are looking forward to your dyno results. My un-calibrated butt dyno tells me there is a marginal gain from the exhaust and BMC filter I installed on my 2.7. I believe I need an ECU flash to really feel the benefits and that is down the road.

Best of luck and let us know how it all turns out.

Boxtaboy,

I believe the u-pipes are slightly different and therefore not interchangeable.




ddb

[23109VC]

that is an expensive system for only "marginal" gains.

i've watched the youtube videos..they sound cool... but it's almost $2000 for that system and if all it does it "sound" cool and leak and throw CEL codes..no thanks.

I bolted up a used pedro muffler - bought from another member here - for about $150 and it sounds pretty good. not as good as the true aftermarket sy stems... but for $150 it was the best bang for the buck...

[ddb]

It's my understanding that any exhaust / intake mod will give you a marginal gain, if you're lucky. Some will probably cost you power.

In all fairness, any system, regardless of cost, is likely to leak or throw CEL, especially if not installed correctly.

Like I said, the real benefit will come when the DME is reflashed.

I'm sure your muffler mod sounds great! Probably better than mine.



ddb

[Jake Raby]

It takes several "Marginal gains" to add up to something of significance.
Even on our much larger engines we only see marginal gains from the current systems on the market.

I've been working on a development especially for our engines for several months now, because it has been clear to me for many moons that the sound and look are the most important characteristics of the current systems on the market.. Neither of these things are primary objectives for my engine program where effectiveness is paramount.

I see people spend 2K+ to make 2-5HP or even lose 20 HP with a certain system. A simple 200.00 crank pulley can easily give 10HP, but it doesn't add sound or isn't shiny.