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

Reply
 
LinkBack Thread Tools Display Modes
Old 07-03-2014, 02:56 PM   #1
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 2,987
throttle blip

so, who want's to build me one of these:

https://classicmotorsports.net/forum/grm/diy-h-pattern-auto-throttle-blipper-set-up-for-the/67068/page1/

it would have to be all electronic (no need for pneumatic as the throttle is electronic and not cable). sensor on the shift linkage, controller, tie-in to throttle signal and brake signal, on/off switch, potentiometer to control amount of blip.


Last edited by The Radium King; 07-03-2014 at 02:59 PM.
The Radium King is offline   Reply With Quote
Old 07-03-2014, 03:58 PM   #2
Registered User
 
seningen's Avatar
 
Join Date: Jul 2008
Location: austin
Posts: 763
With egas the throttle pedal is just a pentiometer

If more gas lowers the resistance
Putting a relay with a set resistance in parallel would allow for auto blipping

Now all you have to do is create that relay control.

M
__________________
Drivers: '08 Cayenne Turbo, 96 993 Çab/Tip (wife's) & '92 964 Cab
Race Cars: '75 911 RSR Clone & '99 Spec Boxster
mike@lonestarrpm.com
seningen is offline   Reply With Quote
Old 07-03-2014, 04:04 PM   #3
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 2,987
thinking about it some more, perhaps even the fancy shift linkage sensor isn't required.

it might be as simple as a controller that intercepts the throttle signal at the pedal, as well as the clutch depressed switch and brake depressed switch (with an on/off switch and potentiometer):

on? - no - throttle signal bypass

brake depressed? - no - throttle signal bypass

clutch depressed? - no - throttle signal bypass

yes to all above? - momentary 5v 'blip' to throttle via potentiometer (to control amount of blip)

so, driving along and everything normal. as soon as you brake AND depress clutch the throttle blips for the downshift. only turn on when at the track to avoid parking lot shenanigans.
The Radium King is offline   Reply With Quote
Old 07-03-2014, 04:11 PM   #4
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 2,987
seningen - you're right, logic might not be required - it might be able to be done with relays - relay on the clutch pedal in series with a relay on the brake pedal in series with an on/off switch. if all on then triggers a third relay that pulls the 'blip' resistor into the throttle circuit. the art becomes the duration of the blip (ie, perhaps not for the entire time that the clutch is depressed) and when the blip happens (ie, not immediately when the clutch is depressed, but almost just before the release of the clutch). there are various types of timed relays that might serve the purpose.
The Radium King is offline   Reply With Quote
Old 07-03-2014, 04:13 PM   #5
On the slippery slope
 
JayG's Avatar
 
Join Date: Mar 2014
Location: San Diego
Posts: 3,429
Garage
Quote:
Originally Posted by seningen View Post
With egas the throttle pedal is just a pentiometer

If more gas lowers the resistance
Putting a relay with a set resistance in parallel would allow for auto blipping

Now all you have to do is create that relay control.

M
Yes, but the resistance of the potentiometer will vary depending on how much gas you are giving it at the moment, so the circuit would need to lower the resistance bu a specific amount. The problem, is that the value you need would vary depending on the potentiometer value

It could probably be done with an Adruino
__________________
2004 Boxster S 6 speed - DRL relay hack, Polaris AutoTop DIY
2004 996 Targa Tip
Instructor - San Diego region, 2014 Porsche Performance Driving School
2013 C300, 2010 Jetta 2011 Mazda 3, 1998 Windstar - Dog van , 2004 F-150 "Big Red"
JayG is offline   Reply With Quote
Old 07-03-2014, 04:17 PM   #6
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 2,987
if you are braking and downshifting into a turn at the track then foot is off the throttle so pedal resistance is a constant. regardless, google is smarter than me ...

AUTO-BLiP Intelligent Downshifts
The Radium King is offline   Reply With Quote
Old 07-03-2014, 08:15 PM   #7
Registered User
 
seningen's Avatar
 
Join Date: Jul 2008
Location: austin
Posts: 763
Quote:
Originally Posted by JayG View Post
Yes, but the resistance of the potentiometer will vary depending on how much gas you are giving it at the moment, so the circuit would need to lower the resistance bu a specific amount. The problem, is that the value you need would vary depending on the potentiometer value

It could probably be done with an Adruino
If you are not heal toe-ing -- then you will not be on the gas.
You'll have one foot on clutch and one on brake.

Therefore your TP would be at 0%.

Let's say for argument sake that your 0% is 10K ohms and your 100% is 0 ohms.
Then you could throttle blip to 50% with a parallel 10K ohm resistor.

1/Rto_blip = 1 /R(0%) + 1/R(blip circuit)

like others have said -- some sort of timing circuit would be used to
enable the duration of the shunting resistor. An old 555 circuit and a pot
enabling a relay would do just fine.

Mike
__________________
Drivers: '08 Cayenne Turbo, 96 993 Çab/Tip (wife's) & '92 964 Cab
Race Cars: '75 911 RSR Clone & '99 Spec Boxster
mike@lonestarrpm.com
seningen is offline   Reply With Quote
Old 07-03-2014, 08:56 PM   #8
Registered User
 
jaykay's Avatar
 
Join Date: Sep 2009
Location: toronto
Posts: 2,365
Quote:
Originally Posted by The Radium King View Post
if you are braking and downshifting into a turn at the track then foot is off the throttle so pedal resistance is a constant. regardless, google is smarter than me ...

AUTO-BLiP Intelligent Downshifts
I need this for my jeep......which is already screwing my driving technique enough as it is!
The pedals are so off plane they are never to be reconciled other than via some gruesome lifter plate monstrosity on the accelerator pedal

Beware that the egas throttle cable disappears into a mysterious cruise control box under the dash. This may be good news as one would have close access to a TPS potentiometer or you could be opening up Pandora's box so to speak

....hmmm think we need to start a good driving shoe group buy lest we release evils of the auto blip!!
__________________
00 986 S....with a few tweaks

Last edited by jaykay; 07-06-2014 at 10:22 PM.
jaykay is offline   Reply With Quote
Old 07-03-2014, 10:36 PM   #9
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 2,987
jk - your pedals are out of alignment because you aren't braking hard enough!

honestly, those dual clutch cars are beasts on the track. they have the advantage on corner entry everything else being equal. manual cup cars and formula cars have throttle blippers for their sequential transmissions. I love heel and toeing, but if that little auto-blip box can give me any kind of an edge then i'll take it.
The Radium King is offline   Reply With Quote
Old 07-04-2014, 06:36 AM   #10
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 2,987
anyone near phoenix? according to their page, potential for a free unit if you let them install it on your car (test on car models that have yet to have tried the device).
The Radium King is offline   Reply With Quote
Old 07-04-2014, 09:18 AM   #11
Certified Boxster Addict
 
Join Date: Nov 2010
Location: Los Angeles
Posts: 7,616
Come to LA and I'll spend a day instructing you at no cost so you can heel and toe like a pro!
__________________
1999 996 C2 - sold - bought back - sold for more
1997 Spec Boxster BSR #254
1979 911 SC
POC Licensed DE/TT Instructor
thstone is offline   Reply With Quote
Old 07-04-2014, 10:21 AM   #12
On the slippery slope
 
JayG's Avatar
 
Join Date: Mar 2014
Location: San Diego
Posts: 3,429
Garage
Quote:
Originally Posted by thstone View Post
Come to LA and I'll spend a day instructing you at no cost so you can heel and toe like a pro!
I live in San Diego and am up in LA often. Can I take you up on that?
__________________
2004 Boxster S 6 speed - DRL relay hack, Polaris AutoTop DIY
2004 996 Targa Tip
Instructor - San Diego region, 2014 Porsche Performance Driving School
2013 C300, 2010 Jetta 2011 Mazda 3, 1998 Windstar - Dog van , 2004 F-150 "Big Red"
JayG is offline   Reply With Quote
Old 07-05-2014, 03:51 PM   #13
Porsche "Purist"
 
Paul's Avatar
 
Join Date: Aug 2003
Location: Wisconsin
Posts: 2,086
Garage
Our eGas uses two pots to verify throttle position. One runs at half the voltage of the other. If not the DME limits the throttle.
__________________
1998 Boxster with 7.8 DME, 2005 3.6 liter/325 hp, Variocam Plus, 996 Instrument panel
2001 Boxster bought new. Installed used motor at 89k.
1987 924S. 2002 996TT. PST2
Owned and repaired Porsches since 1974. Have driven them all the way the Dr intended...
Paul is offline   Reply With Quote
Old 07-05-2014, 08:15 PM   #14
Registered User
 
jb92563's Avatar
 
Join Date: Apr 2012
Location: Riverside, CA
Posts: 1,664
Sounds like he wants an automatic transmission.

The purpose for the throttle blip is matching rpms when downshifting so instead of some predetermined blip rpm, it should really calculate the exact proper rpm hundreds of times per second taking into accoun the decelration rate due to braking and allow you to slam it in gear without clutching at all.

Not sure if the syncro will allow that.

Don't formula 1 cars have something like that?

Interesting idea, lots of room for innovation id say.
__________________
"It broke because it wants to be Upgraded "
2012 Porsche Performance Driving School - SanDiego region
2001 Boxster S, Top Speed muffler, (Fred's) Mini Morimotto Projectors, Tarret UDP,
Short Shifter, Touch Screen Dual Din Radio, 03 4 Bow glass Top (DD & Auto-X since May 17,2012)
jb92563 is offline   Reply With Quote
Old 07-06-2014, 05:26 AM   #15
Certified Boxster Addict
 
Join Date: Nov 2010
Location: Los Angeles
Posts: 7,616
Quote:
Originally Posted by JayG View Post
I live in San Diego and am up in LA often. Can I take you up on that?
Yes, absolutely. Just email me and let me know when you'll be around and let's see if we can meet up sometime. I'll PM you my email address.
__________________
1999 996 C2 - sold - bought back - sold for more
1997 Spec Boxster BSR #254
1979 911 SC
POC Licensed DE/TT Instructor
thstone is offline   Reply With Quote
Old 07-06-2014, 05:48 AM   #16
Registered User
 
jsceash's Avatar
 
Join Date: Aug 2009
Posts: 1,430
Garage
Another one for Porsche. While testing a PDK the sales man told me the 2014 rev matchs automatically on down shift on the manuals as well as the PDK.
__________________
2003 Black 986. modified for Advanced level HPDE and open track days.
* 3.6L LN block, 06 heads, Carrillo H rods, IDP with 987 intake, Oil mods, LN IMS. * Spec II Clutch, 3.2L S Spec P-P FW. * D2 shocks, GT3 arms & and links, Spacers front and rear * Weight reduced, No carpet, AC deleted, Remote PS pump, PS pump deleted. Recaro Pole position seats, Brey crouse ext. 5 point harness, NHP sport exhaust
jsceash is offline   Reply With Quote
Old 07-06-2014, 08:59 AM   #17
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 2,987
the 370Z has done this for several years, and i'm sure other cars as well. appears easy to do on the e-gas cars, and race cars with sequential manual transmissions have been using mechanical blippers for years. e-gas has the added benefit of, as you note, actually matching rpm (the 370z does this, and i preusme the others). on our cars the downshift into 2nd is a bit more aggressive than into other gears; my local track is all 2nd and 3rd gear so i would just set it up for that downshift. i may just have to ask for an auto-blip for christmas.
The Radium King is offline   Reply With Quote
Old 07-08-2014, 12:42 PM   #18
Registered User
 
Join Date: Jun 2012
Location: Frederick MD
Posts: 658
Quote:
Originally Posted by jsceash View Post
Another one for Porsche. While testing a PDK the sales man told me the 2014 rev matchs automatically on down shift on the manuals as well as the PDK.

Yes, PDK will match it perfectly every time and shift about twice as fast as I can. It's still not nearly as fun.

I read the Classic Motorsports link and I just don't get the why behind doing this to a manual car. Porsche put a pretty good pedal setup in the car from the factory. Heal and toeing is such second nature now that I don't really think about it. It takes some time to get comfortable with the process, but is really not that hard with practice.

The biggest problem I have encountered is that the ratios in the 6 spd on the S are not consistently spaced, the lower gears are not close ratio at all and the uppers cogs are very close. I often over blip on 4th to 3rd and under blip on 3rd to 2nd.
shadrach74 is offline   Reply With Quote
Old 07-15-2014, 12:47 AM   #19
Registered User
 
Join Date: Feb 2007
Location: Australia
Posts: 206
Auto Blip

What happened to the art of driving?
__________________
http://i13.tinypic.com/49ied5h.jpg

2000 2.7 Boxster
aussieboxy is offline   Reply With Quote
Old 07-15-2014, 06:48 AM   #20
Registered User
 
steved0x's Avatar
 
Join Date: Dec 2012
Location: FL
Posts: 3,997
Quote:
Originally Posted by thstone View Post
Come to LA and I'll spend a day instructing you at no cost so you can heel and toe like a pro!
My problem with heel/toe is this. My brain will not let me lift my left foot off the clutch while my right foot is on the brake.

My heel toe is coming along, but it looks like this:

Clutch in and then brake.
Even though I want to brake hard, I brake more softly than if I didn't have a downshift, because I think my subconscious wants more time.
Move the gear lever.
Blip the throttle, which also usually causes a slight lift on the brake.
Back on the brake as the revs drop.
Then release the brake and get back on the gas as I release the clutch.

Every once in awhile it works out. I am pretty good about not getting a lurch at the end, but I have usually slowed down way more than I want and there is an odd double pulse of brakes most times.

I rode with an instructor in a prepped 996 at Road Atlanta, and to me it looked like he was doing this:

Brake hard.
Then clutch in, blip and move gear lever, clutch out.
Then finish braking, back on gas and go.

I have tried that (not at the track but once I was back home), and found that my left foot simply would not lift off the floor until my right foot was off the brake.

I think I need to sit in the driveway and practice that a few hundred times. But first I need to make sure that I have found the right combo to practice so I don't ingrain any more bad techniques.

So I wish I was closer to LA... but FL to LA is a long way

steved0x is offline   Reply With Quote
Reply


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 01:40 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page