Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Performance and Technical Chat

Post Reply
 
LinkBack Thread Tools Display Modes
Old 01-08-2017, 11:46 AM   #1
Registered User
 
Join Date: Feb 2016
Location: London
Posts: 79
How much power can you squeeze out of a 986 Boxster S?

We fit a sports exhaust, 987 airbox and 996 throttle body to a 986 Boxster S. What's the final horsepower figure?



https://www.youtube.com/watch?v=kja5LSsUT_g

neil_b is offline   Reply With Quote
Old 01-08-2017, 12:38 PM   #2
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 3,127
very nice. i would question the role that the old tune is playing - both in increased hp, and in the fueling issues. on an unmodified ecu you should be running at stoichometric at low load (to say 4000 rpm) regardless of what you have done to the intake - air and fuel mix is monitored by 02 sensors and kept at stoichometric. you can make the intake and exhaust paths bigger, but the amount of air can still be measured. even if the amount of air is not being monitored properly (ie maf issues, air leaks, etc.) the ecu will trim (add/subtract fuel) to try and maintain stioch. if ecu finds itself having to add/subtract more that 20% or 25% fuel to maintain stoich then you will get a cel. so, you have no cel and are not running at stoich at low load - it must be the aftermarket tune.

i ran that same arrangement and monitored my idle and low load trims and everything stayed well within acceptable ranges.
The Radium King is offline   Reply With Quote
Old 01-08-2017, 04:38 PM   #3
Registered User
 
jaykay's Avatar
 
Join Date: Sep 2009
Location: toronto
Posts: 2,668
Neil,

Great videos...

It wasn't explicitly clear.....Is your buddy running a 987 MAF housing with the standard diameter? 80mm diameter was mentioned. How are you deeming the engine to be running rich?
__________________
986 00S

Last edited by jaykay; 01-08-2017 at 04:45 PM.
jaykay is offline   Reply With Quote
Old 01-08-2017, 04:55 PM   #4
Ben-Auto-Design
 
Ben006's Avatar
 
Join Date: Oct 2014
Location: French Riviera
Posts: 827
Nice!
I haven't had time to watch it completely, I jumped straight to the end, but it is some nice gains!
But... you've remapped it before the mods???
__________________
ASE certified Automotive Master Technician.
Porsche Tech in France.
www.benautodesign.fr
Ben-Auto-Design : Performance parts for 9X6 / 9X7
1982 928 S Euro
Ben006 is offline   Reply With Quote
Old 01-09-2017, 12:32 PM   #5
Registered User
 
Join Date: Jan 2014
Location: New Jersey
Posts: 1,631
Nice video. So, do I understand YouTube correctly-this part 1 was posted 4 days ago and parts 2 and 3 are still to come?

Ben, my understanding is the car was bought with the exhaust upgrade and tune already installed-the plenum and TB were added by the current owner. Parts 2 & 3will be interesting to see how it all turns out.

Last edited by PaulE; 01-09-2017 at 12:35 PM.
PaulE is offline   Reply With Quote
Old 01-09-2017, 12:50 PM   #6
Registered User
 
Join Date: May 2014
Location: S.California
Posts: 2,029
Neil makes the best Boxster videos by far !
There was an excellent Thread recently which gave the tech details of mods. The Thread title was similar to "why is the 3.4l M96 engine in the 996 so much more powerful than the 3.2l in the 986"
How can a 911 3.4 have so much more HP than a 3.2 Boxster S?
and this:
987 v 986 Air box
I can't wait for the video from Neil of removing the stock airbox and replacing it with a 987 -allegedly a 10 hour job of hacking ,smashing and bending up the Boxster.There is a better way if you use Search diligently.I have recently done it.But not for performance or CAI.I really,really needed easier access to the fuel pressure regulator and #4 injector.
I nominate Ben as the guy to make a kit for this project!

Last edited by Gelbster; 01-09-2017 at 12:59 PM.
Gelbster is offline   Reply With Quote
Old 01-09-2017, 05:45 PM   #7
Registered User
 
Ciao's Avatar
 
Join Date: Dec 2015
Location: Denver
Posts: 866
Garage
Neil's videos are clean uncomplicated, easy to understand and succinct.

Good job!
__________________
5280 Cruising @High Altitude
Seal Gray & K&N Filter
Ciao is offline   Reply With Quote
Old 01-19-2017, 12:04 AM   #8
Registered User
 
Join Date: Feb 2016
Location: London
Posts: 79
Quote:
Originally Posted by jaykay View Post
Neil,

Great videos...

It wasn't explicitly clear.....Is your buddy running a 987 MAF housing with the standard diameter? 80mm diameter was mentioned. How are you deeming the engine to be running rich?
Thanks Jay! Richard is running the 987 airbox but has kept the MAF and housing from the original airbox to try to avoid any ECU problems.
neil_b is offline   Reply With Quote
Old 01-19-2017, 12:06 AM   #9
Registered User
 
Join Date: Feb 2016
Location: London
Posts: 79
Quote:
Originally Posted by Ben006 View Post
Nice!
I haven't had time to watch it completely, I jumped straight to the end, but it is some nice gains!
But... you've remapped it before the mods???
The previous owner did it before Richard bought the car. We will discuss this in part 3 - stay tuned!
neil_b is offline   Reply With Quote
Old 01-19-2017, 12:07 AM   #10
Registered User
 
Join Date: Feb 2016
Location: London
Posts: 79
Quote:
Originally Posted by PaulE View Post
Nice video. So, do I understand YouTube correctly-this part 1 was posted 4 days ago and parts 2 and 3 are still to come?

Ben, my understanding is the car was bought with the exhaust upgrade and tune already installed-the plenum and TB were added by the current owner. Parts 2 & 3will be interesting to see how it all turns out.
Cheers Paul! Yep, part 2 goes up today and part 3 in the next week.
neil_b is offline   Reply With Quote
Old 01-19-2017, 12:09 AM   #11
Registered User
 
Join Date: Feb 2016
Location: London
Posts: 79
Quote:
Originally Posted by Gelbster View Post
Neil makes the best Boxster videos by far !
There was an excellent Thread recently which gave the tech details of mods. The Thread title was similar to "why is the 3.4l M96 engine in the 996 so much more powerful than the 3.2l in the 986"
How can a 911 3.4 have so much more HP than a 3.2 Boxster S?
and this:
987 v 986 Air box
I can't wait for the video from Neil of removing the stock airbox and replacing it with a 987 -allegedly a 10 hour job of hacking ,smashing and bending up the Boxster.There is a better way if you use Search diligently.I have recently done it.But not for performance or CAI.I really,really needed easier access to the fuel pressure regulator and #4 injector.
I nominate Ben as the guy to make a kit for this project!
So kind Gelbster! Glad you like them!
neil_b is offline   Reply With Quote
Old 01-19-2017, 12:13 AM   #12
Registered User
 
Join Date: Feb 2016
Location: London
Posts: 79
Part two is now up! Does fitting an underdrive pulley give more horsepower? We fit one then go to the rolling road to find out!

https://youtu.be/CvFdH11y4EI

neil_b is offline   Reply With Quote
Old 01-19-2017, 06:58 AM   #13
Registered User
 
heliguy's Avatar
 
Join Date: Nov 2008
Location: Florida
Posts: 1,111
Quote:
Originally Posted by neil_b View Post
Part two is now up! Does fitting an underdrive pulley give more horsepower? We fit one then go to the rolling road to find out!

https://youtu.be/CvFdH11y4EI

Is this 273 wheel hp or does the dyno convert to crankshaft hp?
heliguy is offline   Reply With Quote
Old 01-19-2017, 07:00 AM   #14
Registered User
 
steved0x's Avatar
 
Join Date: Dec 2012
Location: FL
Posts: 4,143
Quote:
Originally Posted by heliguy View Post
Is this 273 wheel hp or does the dyno convert to crankshaft hp?
It is calculated, in one of the videos (maybe this one somewhere or another rolling road video, maybe the one with the 996) the dyno guy briefly changes the screen to show the actual wheel HP read by the dyno - it is a fair amount lower.
steved0x is offline   Reply With Quote
Old 01-19-2017, 09:43 AM   #15
Registered User
 
Join Date: Jan 2014
Location: New Jersey
Posts: 1,631
Quote:
Originally Posted by neil_b View Post
Part two is now up! Does fitting an underdrive pulley give more horsepower? We fit one then go to the rolling road to find out!
So if I understand correctly, the Dyno's calculated total horsepower is still 273 after fitting the underdrive pulley. Do you have the wheel horsepower figures for before and after? Would like to see if there is a small bump in the net amount reaching the rear wheels, that is what I think the underdrive pulley gives you. (Besides saving your power steering pump at the track.)

PS, great video! If you decide to improve editing quality as discussed in the comments to the video, that would be a bonus, but they are teriffic as is!
PaulE is offline   Reply With Quote
Old 01-19-2017, 10:31 AM   #16
Registered User
 
heliguy's Avatar
 
Join Date: Nov 2008
Location: Florida
Posts: 1,111
Quote:
Originally Posted by PaulE View Post
So if I understand correctly, the Dyno's calculated total horsepower is still 273 after fitting the underdrive pulley. Do you have the wheel horsepower figures for before and after? Would like to see if there is a small bump in the net amount reaching the rear wheels, that is what I think the underdrive pulley gives you. (Besides saving your power steering pump at the track.)

PS, great video! If you decide to improve editing quality as discussed in the comments to the video, that would be a bonus, but they are teriffic as is!
Yes, please post the wheel hp differences, if there are any.
heliguy is offline   Reply With Quote
Old 01-19-2017, 11:43 AM   #17
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 3,127
flywheel hp is extrapolated from wheel hp (ie, increase by 15%) so pretty arbitrary, and can mask/over-emphasize actual gains, esp when dealing with small hp changes. wheel hp is the best measure in these situations i think.
The Radium King is offline   Reply With Quote
Old 01-19-2017, 02:36 PM   #18
Registered User
 
Join Date: Sep 2016
Location: Stow, MA
Posts: 918
Garage
The only thing the dyno can measure is wheel horsepower. If it shows crank horsepower its an estimate, depending on the dyno it can be a fixed offset or a percentage offset.
__________________
2004 Boxster S Silver - FUNTOY
2002 Boxster Base Guardsy Red - FUNBOX
1987 Caterham Super 7 1700 Supersprint
2009 Mercedes Benz CLK 350 convertible
1941 Dodge Luxury Liner Coupe
Anker is offline   Reply With Quote
Old 01-19-2017, 06:51 PM   #19
Registered User
 
Join Date: May 2014
Location: S.California
Posts: 2,029
The take home from this is that Neil paid for a trick part+ a serp belt, hacked off a boss from the engine that is rather useful and spent a bunch of time and other money for no gain of any sort.
The Track guys would claim a benefit in not over-reving the p/s pump ?
The pro-u/d pulley guys claim there is no loss of cooling efficiency or a/c with driving those pulleys slower. Really?
At least Neil did not use the disintegrating version of the u/d pulley.He used a solid one.
I was surprised that when doing this project he did not check the bearings in all the other pullies & ancillaries. At least give the w/p pulley a wiggle ? Maybe that was done in another video?
If Neil wants a trick part that really works for about the same money, he should talk to Ben006 in Post #4- hint ! Ben;s trick part may work particularly well with the 987 bigger airbox?

Last edited by Gelbster; 01-19-2017 at 06:56 PM.
Gelbster is offline   Reply With Quote
Old 01-19-2017, 10:02 PM   #20
Registered User
 
Join Date: Jun 2014
Location: LB, Germany
Posts: 1,487
A dyno doesn't measure hp. It measures torque. HP are calculated from torque and rpm.

There are different parameters that can affect a measurement:
- Temperature
- Humidity
- Grip
- Fuel quality
- Air filter, sparks…

If you don't use a calibrated and certified dyno, measurements are just written lines on a piece of paper.

Funny how people are hunting for 5 hp at the top end. Useless to say that this doesn't affect the driveability of the approx. 250 hp car in any way.

But keep on searching. Always funny to me.

Just my 2 cents.

Markus

Smallblock454 is offline   Reply With Quote
Post Reply

Tags
987 airbox , 996 throttle body , mods , power , sports exhaust


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 07:19 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page