LS3 strange rev limiter

[mospin04]

HI guys.
I have problem with rev limiter in my LS3 engine. This engine is used in drift and rev limiter is important for me. Now rev limiter looks like you lift of the throttle for about 1-2 seconds and then you are back on throttle again. This is first LS3 engine i'm using. Before I was using BMW engines and rev limiter was a lot faster there. It was cut and resume few times for a second. I'm a driver not a mechanic or tuner, so maybe someone could look on tune of my engine and give some advice how to get rev limiter that im looking for.
Best Regards from Poland

[Higgs Boson]

look in the Fuel --> Cut-Off tab. Left side column has all the rev limiters, find the one that matches your issue.

[SICK WS 6]

Just a WAG, but look under Fuel --> Cutoff, DFCO --> and check switchover delay under Control Method. The way it sounds is that after 5 seconds you'll switch from spark to ETC cut. Maybe ETC cut can't cycle fast like you're looking for? Maybe set this higher and see if just spark cut by itself does it?

[mospin04]

Thanks for replies.

I tried to change Cutoff method, switchover delay but problem is still the same.

Is there some other options that can set rev limiter than Engine -> Fuel -> cutoff ?

I tried to change options on this cutoff page but i seems like it doesnt change much. Or I'm doing something wrong.

[5_Liter_Eater]

I would max out the extreme cuts. Right now you have spark cut enabled but the extreme cut is likely also adding fuel cut. I would think spark cut only will be more like what you want.

Weird question, you're not the Canadian guy I saw on Horsepower TV this morning drifting his bimmer with an LS swap are you?

[mospin04]

I didnt try to set extreme cutoff higher then normal cutoff.
I'll be able to try this next weekend so I'll tell you if this will improve my rev limiter. Thanks for the advice.

I'm from Poland and we put LS3 engine into e30 drift car
http://www.facebook.com/photo.php?v=360109254042725

For first 2-3 seconds you can hear rev limiter while I'm going on full throttle.
That is how it sounds now. Is it normal ?

[Kyle LeBlanc]

This is what you want:

Engine -> Fuel -> Cutoff, DFCO

Control Method:
Spark = Enabled
Fuel Cut = Enabled
ETC = Disabled

Misc:
Open "Cmd Torque Delta" Table and set it to look like the attached picture

Set the rev limiter tables to all be the same, and I've noticed that it overshoots it a bit, so set it a few hundred RPM lower than you'd like it to hit.

This is what I do when I tune the ETC LS's for drift and road race.

[bin_ajail]

do you want to make cutoff or backfire(flames) in rev?

[mospin04]

bin_ajail : I want it make cutoff "faster".

Kyle LeBlanc: thanks. I'll check it soon

[LEDbetter]

thanks. I'll check it soon

What did you find out?

[mospin04]

Hey.

Kyle's advice helped.

Thanks guys !!!

[gn2beatu]

You may want to play with your Cutoff RPM Hyst value as well, depending on how fast you want it to resume after dropping RPM. Its in same area Engine -> Fuel -> Cutoff, DFCO, RPM Limits, Cutoff RPM Hyst. Playing with this value will change how fast it bumps on/off the limiter. EX: on E40 ECM its stock at 225rpm (rpm has to drop 225rpm before resuming) Too high of a number can create too long of a time creating unwanted power on/off in corners causing unpredictable handling/power problems. I prefer a shorter time, but every person has thier own taste.

[steve-0]

This is what you want:

Engine -> Fuel -> Cutoff, DFCO

Control Method:
Spark = Enabled
Fuel Cut = Enabled
ETC = Disabled

Misc:
Open "Cmd Torque Delta" Table and set it to look like the attached picture

Set the rev limiter tables to all be the same, and I've noticed that it overshoots it a bit, so set it a few hundred RPM lower than you'd like it to hit.

This is what I do when I tune the ETC LS's for drift and road race.

hi i have the same issue with my ls3 ? can u attached this picture again please ?

[MadPanda]

hi i have the same issue with my ls3 ? can u attached this picture again please ?

I second this motion.

[10_SS]

There is a major recent update to this problem... I cant take credit for it but I did tune the limiter according to this method and can confirm that it really works good.. at least good enough for a "pre limiter" and not to take place of the Extreme limiter in any way. gmtech16450yz is the man due credit for taking the time and thought and risk to make this happen.. I know I would not have went WOT with boost on a stock LS3 expeimenting with this, especialyl fuel cut off, etc, but it works awesome under the many conditions which is basically when your spinning wheels or hit the limiter in a manual trans car and sick of the fall on your face OEM setup. It also works good if you just want to floor it in neutral and let it float around the limit that you choose in the gear table... Neutral does work but the problem is the tail shaft wiggles which triggers MPH, when then makes the ECU think it's not in neutral and then uses 1st gear settings.. so it takes a bit of tuning to get it right, but definitely worth the time, thanks gmtech, really appreciate it.

Original link: https://www.hptuners.com/forum/showt...904#post474904

My reason for really needing is is I have wheel spin on accel and it hovers on the limiter +/- 100rpm, pretty smooth as it uses Throttle cut to limit and if it cant maintain with just that then it uses fuel cut which actually works really good... I was worried about knock but I have a whipple and none with all that boost.

Attached is just one snippet of a log at WOT and hitting my temporary 5500rpm limiter at WOT and it holding RPM while the car picks up speed to match (i have front and rear wheel speed logged) , then shifting and hitting it again. I should note I have these Goodyear Supercar tires and they act strange as you cant tell it's spinning and the problem is I would hit the stock hard limiter and have to let off gas and shift, but then RPM's would be lower than normal since the car was never up to speed. Now... that problem is solved I can just hold it to the floor and wait until I stop feeling acceleration (while RPM is constant).

When I find the original poster/discover.. I'll link it here.. It was discovered about 2-3 weeks ago.

YOu can try it in neutral also, it will bounce pretty mildly.
136e 5500rpm lmiter lots of WOT snippet.hpl

136e Limiter Settings.PNG

136e Settings 2.PNG