Jump to content
The mkiv Supra Owners Club

Stock Traction Control and Boost


hadyn

Recommended Posts

Does the stock traction control limit or slow down the build up of boost on a tt? I ask this as i floored my car in the wet today and noticed that i wasnt building any boost from the reading on my gauge and the TC light flickered on and off and then it suddenly boosted normally again

Link to comment
Share on other sites

yep, similar sensation it didnt feel like fuel cut but the car moved briskly just not as it does on boost, then the boost gauge shot up and the power came back online.

 

I know the TC cuts engine power, but I never thought it would restrict boost

Link to comment
Share on other sites

If you reduce engine power then you'll have less exhaust gas flow so the turbo's won't turn as quickly so you'll have less boost. ;)

 

The revs of the engine will have dropped when you lost traction but will go up again when you regain traction so the boost will go up again.

Link to comment
Share on other sites

Well, the stock TC uses a flint-axe approach of shutting a butterfly plate in the throttle body. This limits air to the engine, so less exhaust gas is produced, so boost falls off.

 

Better TC systems that cut ignition or injectors do it on a pulse-by-pulse basis so engine power is strictly limited to available grip by rapidly altering the power output. Boost doesn't drop off noticeably because it's not just some big four-second-long bitchslap.

 

-Ian

Link to comment
Share on other sites

Well, this trac throttle plate is almost shut, so it's like you have your foot only 20% down. Doesn't matter how much wider you opened the throttle, the other plate is the restriction. Therefore, minimal boost until that plate opened up again.

 

-Ian

Link to comment
Share on other sites

This is why my parting words to you were that to get the best from the de cat you need to turn the stock TC off ;) Doing this has become such second nature to me nowadays that it's as natural as turning the ignition key to "start" :) Your additional mid range torque means the TC is now kicking in where it would not have done prior to the de-catting.

Link to comment
Share on other sites

TBH when 'pootling' to work i dont think of turning the TC off, when im in a 'spirited' mood the TC is always switched off :)

 

Plus my front tyres are past their sell by date so I keep the TC on not to get myself into serious trouble :)

 

I hate stock TC like anyone else btw :)

Link to comment
Share on other sites

 

Plus my front tyres are past their sell by date so I keep the TC on not to get myself into serious trouble :)

 

 

Front tyres aren't affected much by traccy control in a RWD car ;)

 

Chris - I used to switch off the Trac as part of the startup sequence, then I saw sense and installed the trac ECU into my garage shelving. Minimal wiring and those shelves have never broken traction since :thumbs: Freed up loads of space for the fields harness and the O2 sensor module too, how handy ;)

 

-Ian

Link to comment
Share on other sites

TBH when 'pootling' to work i dont think of turning the TC off, when im in a 'spirited' mood the TC is always switched off :)

 

Plus my front tyres are past their sell by date so I keep the TC on not to get myself into serious trouble :)

 

I hate stock TC like anyone else btw :)

 

Even when you're pootling around the stock TC can be down right dangerous IMO. I have a very bad junction onto a busy main road near where I live. I remember when I first got my car, waiting for a gap in the traffic then going to pull out onto the main road, it was wet and I was in a hurry to catch the gap, the TC cut all power and I ended up half way across the road with no power and a bloody great bus coming at me. After that experience I fitted RLTC, pulled the TRAC fuse and have lived with the anoying flashing orange light ever since :looney:

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.