free hit
counters
Boost Controllers - Page 3 - ECU/Freescan/Espritmon - The Lotus Forums - Lotus Community Partner #ForTheOwners Jump to content


IGNORED

Boost Controllers


karmavore

Recommended Posts

LOL Travis on an 80C day I bet you have to wear shorts :)

Lucas- comments ref to the data log you posted.

I never get much more than 10c over ambience on the chagecooler with standard boost.

I'm 1/2 tempted to my make own bleed valve from a regulator and a few turned up fitting just to see what happens if a small leak is introduced to the overboost circuit on a standard chip.

I've had a lot of turbo cars, we used to make out own bleed valves and so on - of course on the Esprit something electronic is needed incase a spike leads to £4,500 rebuild - but it's of interest to see what actually goes on.

Prob with your chip is that with freescan we go from being able to see in, and beyond into theory world.

Again nice thing about boost controller is in the flick of a switch you can re-set to factory and compare an identical run. What I've done in the past is 3am on the deserted motorway leave it in 5th at 20mph then floor it and log the data.

As we were chatting about on the 412BHP thread, your inlet tamps are robbing you of serious HP.

I think it was Dermot that theorised 1hp per 1/2 degree. Im a big fan of not keeping the inlets freezing cold but stopping them getting too hot.

I noticed a massive imporvement on my car when i took the rad housing out and cleaned everything up....debris in the radiator and in my opinion the cowling itself restricts flow somewhat.

When my rad popped I yanked my rad out - fitted a new one with larger bolt on fans and no fan cowling - I am convinced there is more flow becuase my inlets are markedly down (25%) for the same ambience.

I found the standard system was relativly efficient with an electric pump - mine goes from max inlet temp to normal temps in a matter of seconds once off boost. The other thing I did was fit a REAL temp gauage in the inlet and air intake.

The MAT sensor can be a false reading as heat soaks into the aluminium, the outer body of the chargecooler can be hotter than the actual air I have found which conducts into the sensor.

Looking at the absolute real temps you can see the original system works pretty darn well. Rmember also with Dynos is the fan at the front might not create the same airflow need across the chargecooler rad, infact I bet you $100 it doesnt at 5500 rpm in 4th ~105mph. This is another important factor, real world tests show for me that physically driving it on the road yeilded much more favourable results becuase of the increased air flow.

The only thing I would do to drop inlet temps now is to fit a reservoir, like a termal capacitor inline with the charcooler system so it holds more water, more water, faster flow = less d temperature = more average boost.

The idea that other fella had of running the chassis pipes external to the car and in a larger diameter is exactly what I thought would work the best - that way the volume is increased and they dont soak heat inside the chassis tunnel with the radiator pipes etc.

Edited by Jonathan

facebook = [email protected]

Link to comment
Share on other sites


Upgrade today to remove Google ads and support TLF.
  • Replies 73
  • Created
  • Last Reply

Top Posters In This Topic

Indeed but I still have to buy the chip at...looking at PUK....e890 !!!!

Tbh I'd rather spend it on a nice £300 boost controller and reach forward and adjust it with me left hand safe in the knowlege I know whats going on.

Having experience with other products purchased at premium prices from some retailers, you might understand my hesitation to part with my hard earned :)

If I could program the chip myself - so I know exactly whats in it then I'd probably go that option, but at the end of the day apart from a few functions like radiator fan temperature etc - what does it do that a boost controller wont ?

facebook = [email protected]

Link to comment
Share on other sites

A 3rd party boost controller will not allow you to limit boost to between min/max engine coolant temperatures, limit boost when there's an error code set, reduce boost when there's excessive knock or limit overboost duration. I just think that before you junk the stock set up you need to know what you are losing when you do so.

I'm with you on the wanting to know what's going on when you chip the ecu, that's why I've spent so much time trying to decipher the code.

Edited by sailorbob
Link to comment
Share on other sites

Ref the 1st bit - this much is true although I rarely boot it until warm anyways, but for someone less sympathetic I get your point. Rest of it is valid points, I think my situation is slightly different in that I only want to peep a small amount of boost, probably 0.95bar which shouldnt introduce knocks or error codes (the GT3 engine is pretty nice - never knocks under any conditions I've driven it in). If the error light comes on - left hand, switch off boost controller.

If you do finish the code and make it public I'm sure there'd be a substantial reward for your time - I'd pay for it - If I was a clever man I'd do it myself but I have enough things on my plate atm, without learning more stuff.

It's what I've been suggesting for years - group together and pay someone to pull the code apart and make available the options for self tuning to the community.

If I chipped the car I'd rather I know everything that went into it than just 'pay and pray' on someone elses words - might sound harsh to the good suppliers out there but I've been / seen people get bitten too many times by 'experts' only to find out the job could have been done cheaper and better myself.

Chargecooler impellers and suspension bushes spring to mind...... :wacko:

facebook = [email protected]

Link to comment
Share on other sites

Again nice thing about boost controller is in the flick of a switch you can re-set to factory and compare an identical run. What I've done in the past is 3am on the deserted motorway leave it in 5th at 20mph then floor it and log the data.

You sure about that? All the models I'm aware of use their own solenoids.

If you had the trunk panel off you could swap solenoids pretty easily (mine is still connected and hanging out), but as far as switching them...

Luke Colorado, Super Spy.   -  Lotus Owner No Longer

1987 Zender Widebody 560SEC | 1994 Lotus Esprit S4 | 2013 Honda Fit EV (#269)

Link to comment
Share on other sites

Derek, yeah I just checked that - never ever had mine up that far though (boost not RPM) - I could grab the binary for you....will Espritmon do that ? (think it does)

Mine boosts to exactly 0.85 bar (confimred it about 3 ways) I wonder if this is the same for the later GT3's ?

The earlier ones were 240hp, the later quoted as 260 which would make sense, eps since a 2.2 litre S4 is only 265bhp so reducing 200cc and upping the boost makes it fit.

When mine was dynod with some mods it was ~256bhp (although the overboost curve was not exactly smooth) and mine is an earlier GT3.

Answer to me current prayers could be the later code then... ?

I also have some other binaries for the GT3 - if I can dig them out do you want to take a look ? Whats your e-mail or send a mail to me (addy in sig) and I'll send them back for you to look at.

Lucas, I mean turn it back to normal - ones I'm lookingat you can program overboost and then at the push of a button the thing goes dead and stop working allowing the original ECU to play instead.

facebook = [email protected]

Link to comment
Share on other sites

Lucas, I mean turn it back to normal - ones I'm lookingat you can program overboost and then at the push of a button the thing goes dead and stop working allowing the original ECU to play instead.

Define normal? Do you mean back to the spring pressure?

Luke Colorado, Super Spy.   -  Lotus Owner No Longer

1987 Zender Widebody 560SEC | 1994 Lotus Esprit S4 | 2013 Honda Fit EV (#269)

Link to comment
Share on other sites

As in switching off and handing the control back to the ECU.

Show me. Unless it uses the same voltage rage as the OEM solenoid and the wires from the ECU and from the boost controller are switched, I can't see how this is done.

Luke Colorado, Super Spy.   -  Lotus Owner No Longer

1987 Zender Widebody 560SEC | 1994 Lotus Esprit S4 | 2013 Honda Fit EV (#269)

Link to comment
Share on other sites

I've not got it fitted mate :P

The OEM solenoid is till there inline with the new solenoid. They way I see it working - and it's been explained to me (which I am initially sceptical about) - On boost the OEM will rise to the chipped level, both the boost controller and the ECU and paying attention.

Say you set the boost controller to 0.85 (std boost for discussion sake) the ECU will pretty much manage this one, the boost controller may chirp in here and there depending on which one reads and controlls the boost faster.

Now turn it upto 1bar

Initially the ECU is handling the boost until it gets to chip controlled level (0.85) then it starts to moderate and maintain that level. The boost controller still wants to play so it's bleeding more air to get it to 1Bar. The ECU goes hang on, we're getting too much boost, and will ultimatly shut its solenoid off completely to try and reign it in - however now full control is on the boost controllers solenoid whilst the ECU is working out why when it's overboost solenoid is shut the boost is still rising....I'm convinced it'll have the arse with this as I've seen the ECU have the arse with much less important probs before but we'll see I've still not fully decided what route to go.

Some of the expensive contollers I have seen have knock sensing and so on as well ~ $500 but you're getting a fully tunable chip in some respects.

I say this is how it's been explained to me and seems logical - show us your installation and we'll see whats the same/different.

facebook = [email protected]

Link to comment
Share on other sites

I've not got it fitted mate :P

If you say so, man, but it doesn't sound like you're convinced it works!

Luke Colorado, Super Spy.   -  Lotus Owner No Longer

1987 Zender Widebody 560SEC | 1994 Lotus Esprit S4 | 2013 Honda Fit EV (#269)

Link to comment
Share on other sites

Below my 2 cents

The boostroutine is run every 25 milliseconds like Sailobob said. There is a counter in the software which is incremented by one every 6.25 msec. Every time the 12.5 msec bit is set (so the period between each time the bit is set is 25 msec.) the boost routine is executed.

The equation used by Freescan for MAP is not the right one. The correct one to use is:

P = (MAPADC / 255 + 0.04) / 0.005 were P is kPa.

(MAP range is 8 kPa - 208 kPa)

Freek

Edited by fjmuurling

Esprit Freak

Link to comment
Share on other sites

The boostroutine is run every 25 milliseconds like Sailobob said.

My 2 cents:

So what? While 40 times a second sounds fast, we're talking about real time processing here. How many times a second are other routines run? How fast are other boost controllers? With out a context I don't think you can claim 25 milliseconds is adequate.

For example: @ 6000 RPM you're getting more the twice the combustion cycles as you are boost adjustments. Is that enough?

Luke Colorado, Super Spy.   -  Lotus Owner No Longer

1987 Zender Widebody 560SEC | 1994 Lotus Esprit S4 | 2013 Honda Fit EV (#269)

Link to comment
Share on other sites

  • Gold FFM

Lucas, when considering whether 40 Hz is fast enough or not, it is important to keep in mind that the result of the computation is used to control the wastegate. The (limited) control bandwidth of this mechanical construction determines the minimum requirements on the update-rate of the computation, not the combustion cycle. 40 Hz or any higher update-rate will not make a difference since it just provides more reference point in an already very smooth command reference (pressure).

Link to comment
Share on other sites

Erik: what I think you said (in what can only be refereed to as engineering speak; are you German? :innocent: ) is that the capsule can only cycle so many times in a second, and that value is far less 40, true?

If so, that makes sense, but how do you now this? What are the factors involved? I.E.: does the spring pressure effect the rate? Also, is there harm in having more data points?

It seems to me that having more data will only make things smoother, even if not every point will be used every time.

Ahhemm....pics ? Cmon lets see 'em

My setup is straight forward.

The OEM solenoid is disconnected from both vacuum lines, but still connected to the ECU.

The new solenoid is connected to both vacuum lines and electronically connected to the Controller.

30-4350_1.jpg

Luke Colorado, Super Spy.   -  Lotus Owner No Longer

1987 Zender Widebody 560SEC | 1994 Lotus Esprit S4 | 2013 Honda Fit EV (#269)

Link to comment
Share on other sites

The operating frequency of the wastegate solenoid is 32 Hz. A lot of routines in the ECU are only run every 100 mSec. The shortest interval is 6.25 mSec.

Another thing to think about is that the engine RPM can only change a certain amount per sec (certainly not from 0 to 6000 RPM in 1 second) and it also takes time for the turbo to spool up / down when the exhaust gas flow changes. All things considered I think the control frequency of the wastegate is quite OK.

BTW what is the controlling frequency of the various aftermarket boostcontrollers ??

Freek

Esprit Freak

Link to comment
Share on other sites

BTW what is the controlling frequency of the various aftermarket boostcontrollers ??

Freek

I can't find any documentation on the subject.

What I do know is that the boost control before and after the installation of the aftermarket controller is night vs. day. I didn't install it to get more boost, just consistent boost.

Luke Colorado, Super Spy.   -  Lotus Owner No Longer

1987 Zender Widebody 560SEC | 1994 Lotus Esprit S4 | 2013 Honda Fit EV (#269)

Link to comment
Share on other sites

Thats one prob mine has, the boost 'level' under direct wide open throttle isnt exactly stable - it fluctuates here and there. Thats why when the car was dynod the bloke lifted off too early, the boost / power dropped slightly and gave me a bad reading on the last run.

facebook = [email protected]

Link to comment
Share on other sites

Are you using a standard turbo? I don't have an boost charts before my new turbo (sadly) but with the new one boost was all over the place on back-to-back runs.

Now it's quite stable.

post-78-0-77714400-1305845797_thumb.jpg

Luke Colorado, Super Spy.   -  Lotus Owner No Longer

1987 Zender Widebody 560SEC | 1994 Lotus Esprit S4 | 2013 Honda Fit EV (#269)

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.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  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...