can i help you?

[xtcaust]

i feel like a sponge asking all these questions so if there is anything i can help with i'd like to!

i have been tuning computers since 1988 when they were trimpots every 1000 rpm and a separate 1 or 2 for boost through to the latest motec's, ems, autronic and the list goes on

i have become a master at tuning pcm's to fool the tcm in zf 6sp to do as i ask in the ford range

i have dyno experiance both use and design

hope i can help and bring something usefull to this forum?

[turborabbit]

i feel like a sponge asking all these questions so if there is anything i can help with i'd like to!

i have been tuning computers since 1988 when they were trimpots every 1000 rpm and a separate 1 or 2 for boost through to the latest motec's, ems, autronic and the list goes on

i have become a master at tuning pcm's to fool the tcm in zf 6sp to do as i ask in the ford range

i have dyno experiance both use and design

hope i can help and bring something usefull to this forum?
====
aftermarket ecus have slightly different approach.
there you have ALL the info, good documentation, ready software, tools and of course, in most times REALTIME access to maps... That's why you can concentrate on WHAT you tuning... So I guess we can ask you some practical questions of general SI engines nature...

Hmm... can you tellme how to adjust maps in one N.A. engine, so I get fire from exhaust and explosion sound during gearchange. Without extra hardware.

[vwmike]

It sounds like you're talking about anti-lag. Timing is retarded on decel so that combustion happens very late and carries into the exhaust spooling the turbo.

[CTW John]

It sounds like you're talking about anti-lag. Timing is retarded on decel so that combustion happens very late and carries into the exhaust spooling the turbo.


Mike, he said NA so no turbo to spool :p
It's normally the effect of a race cam with wide overlap.

[turborabbit]

It sounds like you're talking about anti-lag. Timing is retarded on decel so that combustion happens very late and carries into the exhaust spooling the turbo.
====
shhhhh i was talking about NA as you may noticed ;)

[Philip]

Is this a test or do you want the answer?

[turborabbit]

Is this a test or do you want the answer?
====
Test? No. I want answers

[ecu_flash]

Waking up the Neighbourhood... :)

[Philip]

This is from power cut and off throttle cuts involving just spark, and not fuel cuts. So fuel continues, which ignites on the exhaust. This has been removed from modern cars due to the catalysor damage from overheating, emmisions, and economy. None of these are of interest to a race car. The reason for this (not for show!!) is to increase the response from closed throttle compression braking to rapid pick up. Hi cams and no catalysor will make bangs, but removal of fuel cut will give a constant stream of flame. That is the theory. To put it into practice would take may take more than damos byte changes, but complete rewriting?
A map would be needed to command injector pulsewidths with no airflow.
Or am i just explaining what you know, but no help on how!

[ecu_flash]

Also would need to change the injector pulse width, which goes to 0m/s when TPS voltage says 'throttle closed' but engine rpm is above i.e. 1500 rpm.

Unless you can do this with the fuel which was already injected before you lifted your foot.

[turborabbit]

This is from power cut and off throttle cuts involving just spark, and not fuel cuts. So fuel continues, which ignites on the exhaust. This has been removed from modern cars due to the catalysor damage from overheating, emmisions, and economy. None of these are of interest to a race car. The reason for this (not for show!!) is to increase the response from closed throttle compression braking to rapid pick up. Hi cams and no catalysor will make bangs, but removal of fuel cut will give a constant stream of flame. That is the theory. To put it into practice would take may take more than damos byte changes, but complete rewriting?
A map would be needed to command injector pulsewidths with no airflow.
Or am i just explaining what you know, but no help on how!
====
Nice essay, thanks Philip.
What I cant understand is what racing has to do with closed throttle, especially while gearchanging?
As for flames and explosions, the problem is that I've done this few times for few lads who wanted this for show... and every time with different ways... so wanted to hear other people's opinions.

[turborabbit]

Also would need to change the injector pulse width, which goes to 0m/s when TPS voltage says 'throttle closed' but engine rpm is above i.e. 1500 rpm.
====
IThere's timer for engaging this type of fuel cut. If you dont shift like granny, you'll be able to change gears few times while waiting for it ;)

[Philip]

====
Nice essay, thanks Philip.
What I cant understand is what racing has to do with closed throttle, especially while gearchanging?


What form of racing?, or why it is involved in any racing?
It is a form of extreme acceleration enrichment, and keeping the valves damp. I'm still looking for a more technical explaination though.

[turborabbit]

What form of racing?,
====
Dunno, the one you were talking about


or why it is involved in any racing?
====
No idea, as I said above I only needed that few times for show

Now one lad asked me to make his idle crappy, to pretend he's got high cams :)

[Philip]

OK, so just for show, with NA.Youcould use propane injection (it has the benefit of pretending to be nitrous too!) with extra spark plugs.
For bad idle, chose any 4 spark plugs with the correct thread, different nose height to give higher duration ;) or reach under his intake tubing and secretly cut with a knife!

[turborabbit]

OK, so just for show, with NA.Youcould use propane injection (it has the benefit of pretending to be nitrous too!) with extra spark plugs.
====
.... with stock ecu without any hw mods




For bad idle, chose any 4 spark plugs with the correct thread, different nose height to give higher duration ;) or reach under his intake tubing and secretly cut with a knife!
====
For bad idle, i just make few BIG shifts in basic fuel and advance, so the adaptation algo gets out of it's range and engine falls into loop searching for correct fuel and spark that will suit it better. Cruel stuff brrrr

[vwmike]

Mike, he said NA so no turbo to spool :p
It's normally the effect of a race cam with wide overlap.

Sorry, it was late and I was tired.

My Rabbit shoots fire when it hits the rev limiter or when I use the launch control....but that's CIS with a Rotomaster T04 and an MSD 6AL. ;)

[turborabbit]

Sorry, it was late and I was tired.

My Rabbit shoots fire when it hits the rev limiter or when I use the launch control....but that's CIS with a Rotomaster T04 and an MSD 6AL. ;)
====
Yea, my rabbit enjoys his last days with CIS, preparing exchange engine with megasquirt.

[xtcaust]

It sounds like you're talking about anti-lag. Timing is retarded on decel so that combustion happens very late and carries into the exhaust spooling the turbo.
also with added fuel that is if you are doing it with an n/a engine no cat helps too as cat will melt!

[xtcaust]

This is from power cut and off throttle cuts involving just spark, and not fuel cuts. So fuel continues, which ignites on the exhaust. This has been removed from modern cars due to the catalysor damage from overheating, emmisions, and economy. None of these are of interest to a race car. The reason for this (not for show!!) is to increase the response from closed throttle compression braking to rapid pick up. Hi cams and no catalysor will make bangs, but removal of fuel cut will give a constant stream of flame. That is the theory. To put it into practice would take may take more than damos byte changes, but complete rewriting?
A map would be needed to command injector pulsewidths with no airflow.
Or am i just explaining what you know, but no help on how!

the flames can be produced as posted and the flames are suposed to keep up the airspeed in the exhaust for better airflow on accel from decel but it only works 2/5's of nothing (f/a)

as such i dont do it as it seems to foul plugs more than help

[xtcaust]

====
Yea, my rabbit enjoys his last days with CIS, preparing exchange engine with megasquirt.

do i say my prayers now for you or do you want me to wait?

[alfons]

Here is more information on problem

http://www.checksumm.com/chiptuning/checksum-problem-dead-t2030/index.html

Thanks