ALS discussion

[jsmcortina]

decided that i want to try full blown air injection als as this is not hard on the exhaust valves and cooling system and head. it also leaves the throttle closed so your brake booster works.

Is this the same as "hyperbar" ? Where you burn fuel in the exhaust system ahead of the turbo?

James

[rb26dett]

i'm not sure what hyperbar is, but it sounds like it yes, you tune pig rich, and dump in air, as the air hits the hot rich exhaust, it finishes the burning process ahead of the turbo. its what wrc cars use. the celica gt4 rc cars had it too. i imagine that i'll need to write my own code when the time comes as thats definitely not something that many people are crazy enough to want to use on the road.

here are a couple of pics of the toyota system, and a link to what audi used to do (which is extreme and not really what i want to do.




http://bufkinengineering.com/Umluft.htm

i'm not interested in getting it spooled for launch (need the traction not being spooled gives) but rather having totally consistent throttle response when doing skids. the thing with a big turbo is that its producing big power while its spinning, but in a particular slide you may need to lift to stop the tail overtaking you. as soon as you lift, the turbo unspools and when you refloor it to maintain the slide there isnt enough torque to do it at the instant you need it and you jerk in and out of sideways in the ugliest way. i'm sure with more practice i could do better with it, but its less than ideal. i suspect the unnatural act of flooring it too early would do the trick, but thats just confusing at a time when its instinct driving the car. if i fail to get serious als working adequately i'll be downsizing for winter to a td05hr/vf34/t28 or something preferably ball bearing for insta-spool on reapply.

fred.

[jsmcortina]

Hyperbar, from what I read of it, injects fuel, air and sparks in the exhaust. Apparently it is outlawed in some racing classes because it is too good...

James

[rb26dett]

i was just having a google about it now. it seems that its mainly used on huge diesels and in some cases the turbine can continue to function and generate electricity WITHOUT the engine running

someone suggested that i could dump in diesel with the air to provide more poke to the turbine. i might be partial to this, but i'm way too scared to dump petrol in there. at least with diesel it wont burn unless its 400C+

fred.

[digi]

hi all

watch this! MS1/extra with baldur ALS code.

http://www.youtube.com/watch?v=1DvBkba0cqc

Opel Ascona 2.4 turbo RWD squirted.
GREAT work guys! we really need ALS in MS2.

[jsmcortina]

So just how much retard do you need?
The existing code can do 10ATDC easily. More would require some thought.

Do I understand correctly that you'll want an ALS arming switch in anything but a 100% race car ?

Then

Code: Select all

 if (switch on)  and ( throttle <setpoint> setpoint )

the ALS is enabled (idle valve opened and timing retarded)

(Why won't the forum software accept the above unless I make it code? It keeps mangling it and missing out the rpm bit)
I GIVE UP -> TRY IN WORDS
if switch is on and throttle is less than setpoint and rpm is greater than setpoint then enabled ALS

James

[rb26dett]

I sure do!

If i were at home, i'd be happy to test it too. its only a snap crackle pop from the outside, and if you only arm it when you need it for a bit of a play, then its not going to kill the turbo that quick. esp not if the exhaust housing is pretty big and freeflowing.

fred.

[digi]

So just how much retard do you need?
The existing code can do 10ATDC easily. More would require some thought.

I need up to 35ATDC

Do I understand correctly that you'll want an ALS arming switch in anything but a 100% race car ?

Yes but is possible to make mild ALS with less ATDC. This cant be dangerous for turbo.

Then

Code: Select all

 if (switch on)  and ( throttle <setpoint> setpoint )

the ALS is enabled (idle valve opened and timing retarded)
I GIVE UP -> TRY IN WORDS
if switch is on and throttle is less than setpoint and rpm is greater than setpoint then enabled ALS

Correct but extra fuel is needed because of AFR tuning. Lean ALS make exhaust gas too hot and burnt pistons.
Example ALS table:
ALS > on - off
PWM Idle solenoid > 0 - 100% [duty]
Timeout to disable > 0 - 20 [sec] ; how long ALS works after foot down from gas pedal (under TPS theshold value).
TPS threshold > 0 - 255 [ADC] ; over this value ALS off
Missfire > 0 - 2 [spark] ; exhaust gas cooling function, if 1 - fire,fire,miss,fire; if 2 - fire,miss,fire,miss (make bang - bang at idle )
RPM target1 > 0 - 9000 [RPM] ; idle valve must be tuned at least this value
RPM target2 > 0 - 9000 [RPM]
RPM target3 > 0 - 9000 [RPM]
RPM target4 > 0 - 9000 [RPM]
Fuel addition1 > 100 - 255 [%]
Fuel addition2 > 100 - 255 [%]
Fuel addition3 > 100 - 255 [%]
Fuel addition4 > 100 - 255 [%]
Spark timing1 > 0 - -55 [BTDC] ; value added to normal spark table in actual RPM.
Spark timing2 > 0 - -55 [BTDC]
Spark timing3 > 0 - -55 [BTDC]
Spark timing4 > 0 - -55 [BTDC]

I hope this helps and sorry for my poor english. ;)

[jassem99]

I've always pondered at the possibility of using the switchable maps and launch control features of the Extra code to implement a crude form of antilag. I was thinking along these lines:

-Create NOS tables (ie VE table 3 and spark table 2) that have extra fuel and grossly retarded timing in most of the bins
-Use output1 (for example) to activate the NOS tables below a certain TPS ADC count, hence promoting combustion just before the turbo
-To have any hope of making this effective, a lot of air must be introduced into the engine (throttle kicker/idle valve etc)
-This increased airflow will make the idle ridiculously high (2000-3000rpm at least), so one way of keeping engine speed under control might be to use the launch control set to fuel only revlimiting at 1000-1500rpm
-The transition between NOS tables and standard tables might take some tuning to get just right (if at all), and how badly the engine will idle with the launch control activated is also something to consider.

When I get the chance I might try the above silliness, but if someone else wants to punch any holes in it please do so and save me the time spent testing. I find it a shame that this feature is only (albeit beyond my abilites) a firmware re-write away, and would increase the appeal of the Extra code to even more amateur racers out there. If a timer is implemented (hard code or megatune adjustable with stern warning) then it won't be too bad on the turbo.

Basil

[digi]

I've always pondered at the possibility of using the switchable maps and launch control features of the Extra code to implement a crude form of antilag. I was thinking along these lines:

-Create NOS tables (ie VE table 3 and spark table 2) that have extra fuel and grossly retarded timing in most of the bins
-Use output1 (for example) to activate the NOS tables below a certain TPS ADC count, hence promoting combustion just before the turbo
-To have any hope of making this effective, a lot of air must be introduced into the engine (throttle kicker/idle valve etc)
-This increased airflow will make the idle ridiculously high (2000-3000rpm at least), so one way of keeping engine speed under control might be to use the launch control set to fuel only revlimiting at 1000-1500rpm
-The transition between NOS tables and standard tables might take some tuning to get just right (if at all), and how badly the engine will idle with the launch control activated is also something to consider.

When I get the chance I might try the above silliness, but if someone else wants to punch any holes in it please do so and save me the time spent testing. I find it a shame that this feature is only (albeit beyond my abilites) a firmware re-write away, and would increase the appeal of the Extra code to even more amateur racers out there. If a timer is implemented (hard code or megatune adjustable with stern warning) then it won't be too bad on the turbo.

Basil

Already tested something like this:

retard ingniton above 3000
retard to -10
enable launch when tps above 50
launch control hard re limit 6000
flat shift arming rpm 6000.

very poor antilag. For proper rally ALS you need at least 15-20ATDC.

[Jon k]

James,

Does the code in MS2/E still prevent anything over 10ATDC? Was that anything specific about memory availability in MS1/E or was it simply because of the way the angles are calculated? It'd be nice to run more retard, if at all possible... but not a super high priority by any means.

[youask]

easy way is a throttlekicker to let more air into the intakemanifold

Like opening the throttle 10-20%

[jsmcortina]

James,

Does the code in MS2/E still prevent anything over 10ATDC? Was that anything specific about memory availability in MS1/E or was it simply because of the way the angles are calculated? It'd be nice to run more retard, if at all possible... but not a super high priority by any means.

They are both presently limited to 10ATDC as the most retard by the way the code is written. MS1 is unlikely to change, but MS2 might do in 2.1 codes.

James

[rb26dett]

is it possible to hack it by using a large advance value and skip a cycle and go to the next? or is there an upper limit on advance too? (i assume so, just curious though)

fred.

[460stang]

Launch control would also benefit from more than 10 deg retard. I currently am using MSD DIS2 to retard up to 30 deg. This gets me 25 psi instead of 10 psi before I launch. Launch control would also work better with an enrichment option (which I think I will be able to work around a NOS table). Just to those who may be working with antilag some of the options would definitely be a plus for launch control.

As far as I can see, launch control and antilag are only different in 2 ways. The RPM that you are trying to hold (probably less than 2000 RPM for antilag) and antilag needs to provide its own air compared to launch control which has your throttle wide open.

I am sure that the settings for antilag will have to be much more aggressive, and they will likely be triggered by and external switch and a min TPS setting. Where as launch control works best when triggered over a given RPM and an external switch.

[suberimakuri]

Fred: I may have misread, but I strongly recommend NO Antilag of any form for drifting.. There is way enough heat and other issues going on. If turbo is really unmanageable, swapping to something smaller is a good idea. But just about anything can driven.

[rb26dett]

Hi Karl hows Japan?

I'm guessing that you have kinda misread it. Drifting on the street for a few minutes at a time, and circuit driving for 10 - 20m at a time. not serious drifting like you ;-) though, i might give it a shot at some stage, i wont try it with next to no power, i'm probably not that good ;-)

the turbo is good for 530crank hp and its on a 2l twincam similar to a 4g63. for driving it spools fine, fully on boost at 5k and strong by 4k, and that will improve when my embarrassing 1hr wot tune gets improved somewhat, but what its not ok for is instant response. you are right that it could be driven, but you would have to floor it earlier than normal to get it to spool when you need it. pretty unintuitive. the turbo is industrial spec and cheap, i have massive cooling (twice what the engine currently needs), and i dont want to run retard lag if i can help it, though i'm willing to give it a try. if i run air injection lag, the only things in danger are manifold, turbo, wastegate, o2 sensor and exhaust. none of them are a big deal to replace, and because i'll only do it intermittently, it should last ok.

are there any reasons other than "the turbo might melt, and the engine might overheat" that you have for saying that? i'm interested to learn from your experiences on it, i reckon your word can be trusted

at the moment it wont even stay at 85C, if i so much as move it through the air at all, the temp drops to 55C and thats with a properly installed closed thermostat. idling or doing a static burnout will bring it to 85, but motorway or street cruising at 50 - 100kph just cools it off too much. might be ok in summer. we'll see. if not, i can just block off the front partially, or put that on my skyline and get a smaller skyline radiator for it.

heres a pic of the setup :
http://i50.photobucket.com/albums/f323/ ... C_2276.jpg
and the turbo and downpipe :
http://i50.photobucket.com/albums/f323/ ... 0_4286.jpg
http://i50.photobucket.com/albums/f323/ ... 0_4272.jpg

hope that puts it in perspective.

thanks for your concern and advice! appreciated.

fred.

[suberimakuri]

ok, sweet as.
any real circuit work will put a lot of strain on it as is... everything gets way hotter. Thats all.
Drifting with laggy turbos is harder, but i still like the challenge. (been there before). As you say, have to get on the gas way earlier.
Anyways, I don't have anything useful to contribute to this ALS discussion so will keep out.
Setup looks cool man. keep at it!

[rb26dett]

any real circuit work will put a lot of strain on it as is... everything gets way hotter. Thats all.

i've done a bit of non drift track time, and enough evading the law to know what hot means

http://i50.photobucket.com/albums/f323/ ... 0_4087.jpg
http://i50.photobucket.com/albums/f323/ ... 0_4086.jpg
http://i50.photobucket.com/albums/f323/ ... 0_4085.jpg
http://i50.photobucket.com/albums/f323/ ... 0_4084.jpg
http://i50.photobucket.com/albums/f323/ ... 0_4083.jpg
http://i50.photobucket.com/albums/f323/ ... 0_4082.jpg

as it turns out, smearing molten steel works too, and 3 front pads are enough at manfeild ;-)

hence the radiator

Drifting with laggy turbos is harder, but i still like the challenge. (been there before). As you say, have to get on the gas way earlier.

thing is, i want it to be fun (read easy, and read safe(public roads...)) but before i get anything like an ALS system setup, i'll be giving it more of a try. maybe i'll get to like it?

Anyways, I don't have anything useful to contribute to this ALS discussion so will keep out.

hard to believe!

Setup looks cool man. keep at it!

cheers

[RickRST]

Hi.

You need anything upto 90ATDC for ALS/Lanch. The idea is that you open the idle valve 100%, or better, have a dedicated valve, and dramtatically richen the mixture. You then use the retard to set the RPM - more retard drops the RPM, and spools up the turbo. Different engines turbos need different values. Have a look at the thread in the link at the start of this post.

There needs to be a master arm switch, and also a timer - to prevent the the retard situation from being on too long, causing heat build up. When armed, the car will not idle properly, popping in banging in ALS mode. The more air you bypass, the more aggressive the system. Anything using stock idle valves will have little or no effect on the life of the turbo.