Lightend flywheel and stalling

[480sx]

I read a little piece of information the other day that was saying that a stalling issue can be caused by a reduced amount of rotational mass on the drivetrain. I have a stalling issue and its manageable, but its still damned annoying when the car doesnt want to idle down from revs.

So my question is.. To those of you who have a lightened flywheel, do you have issues when your car is idling down from rev's? If not, did you do anything to fix it, or was there never a problem at all?

[sunnys14]

Get used to it. My revs drop way faster than stock with my ASP pulley + Fidanza flywheel and aluminum driveshaft.

What is your base idle set at? I raised mine to about 950rpm and it helps with the stalling.

[driftin_sr20det]

I installed an aluminum flywheel on my buddy's SR and boy did it stall. Like every chance it got, haha. Those 9lb flywheels are just too much of a weight loss, I've never had a problem with my lightened steel one. So it seems a little is alright, but cutting the weight down too much will cause you to stall. Does great for the revving though! haha

[WDRacing]

The lightening of the rotational mass definitly effects the increase and decrease in rpm...obviously. One adverse effect is always the stalling point. The most used corrective action is an increased idle speed. I was contemplating a timed solenoid valve. Have it triggered when the tps goes to closed, have the valve open for 5 seconds or so to work inconjuction with the IACV. That way you can maintain a normal idle speed and not have the stalling issue. I bet this would even prevent BOV stalling issues.

WD

[bruinbear714]

I read a little piece of information the other day that was saying that a stalling issue can be caused by a reduced amount of rotational mass on the drivetrain. I have a stalling issue and its manageable, but its still damned annoying when the car doesnt want to idle down from revs.

So my question is.. To those of you who have a lightened flywheel, do you have issues when your car is idling down from rev's? If not, did you do anything to fix it, or was there never a problem at all?

I have a lightweight flywheel, underdrive pulley, and electric fans and my car drops to idle rpm fine from high revs (4000+ down to 850).

You might have a vacuum leak if your idle is erratic, or your car just needs a tuneup.

[kouki_hmongster]

WD you should try it out or make a DIY thread, because this sounds good. plus i never knew a light weight flywheel would cause this.

[1mansho]

I was also in the market to get a flywheel before i installed my exedy stage 2. I just heard that if you daily your car, you put more stress on your clutch and wear it out faster cause you have to rev higher everywhere you go. I stuck with my stock one and man im glad i didnt get light flywheel, id be stalling all the time cause the clutch grabs really hard. I'd advise you to stick to stock if you worry about drivability.

[WDRacing]

I have a light weight Fidenza and a SPEC STG IV clutch...no stalling nor driveability issues for me. Less rotating mass is a good thing, especially if it's a balanced setup.

WD

[C-Kwik]

I wanna say the S13's cut fuel over a certain RPM when decelerating the motor and kick it back on at a particular RPM. If this is the case, the lower threshold would likely have been set based on the factory flywheel (and its corresponding rate of deceleration). So if its delecerating faster with the lightened flywheel, the lower threshold may be at too low an RPM to effectively "catch" the motor before it stops. Depending on how you're tuning your motor, the fix may be as simple as a reflash or a change in some settings.

[kouki_hmongster]

I was also in the market to get a flywheel before i installed my exedy stage 2. I just heard that if you daily your car, you put more stress on your clutch and wear it out faster cause you have to rev higher everywhere you go. I stuck with my stock one and man im glad i didnt get light flywheel, id be stalling all the time cause the clutch grabs really hard. I'd advise you to stick to stock if you worry about drivability.

stage 2 clutch is okay whoever told you that cant handle the clutch. i drove my bros 97 prelude w/ clutch master stage 2 and it ran fine. also driven my buddy's skyline gts-t stage 3 clutch and its fine. you dont have to revv it higher in order to shift. plus if u turbo a ka, the stock clutch will start slippin and that will cause even more wear right. Make sense to u?

my stock clutch replacement exedy brand last only about a month, it was slipping like crazy w/ 241wtq stock t25. took it off and it was completely gone.

[1sikS13]

i have a fidanze and i uped my idle to about 900 before that it would drop way low. I mean way low

[DevilMB3017]

I wanna say the S13's cut fuel over a certain RPM when decelerating the motor and kick it back on at a particular RPM. If this is the case, the lower threshold would likely have been set based on the factory flywheel (and its corresponding rate of deceleration). So if its delecerating faster with the lightened flywheel, the lower threshold may be at too low an RPM to effectively "catch" the motor before it stops. Depending on how you're tuning your motor, the fix may be as simple as a reflash or a change in some settings.

Yeah, I'm going to agree with this. I have a tuned ECU and I see fuel come back around a hair under 1K, but I idle around high 800 or low 900 depending on how it's acting that day, lol. I'm not sure about stock, but I'm sure it's similar.

[s13rb25det]

I have a ebay "12" pound flywheel which is reaLLY 14LB btw. and I did notice it would stall more often when I installed it. I changed my iacv and bumped the idle to 800rpms and have zero stalls now.

[ioioioio]

Interesting thread.. thanks
Modified by ioioioio at 2:52 AM 4/19/2009

[SX APPEAL]

Never really have stalling problems with my fidanza, but I usually leave it in gear while decelerating and only disengage the clutch right before I stop, so its pretty much at idle speed by then anyway, idk just personal preference.

[silviaslider37]

I have a ebay "12" pound flywheel which is reaLLY 14LB btw. and I did notice it would stall more often when I installed it. I changed my iacv and bumped the idle to 800rpms and have zero stalls now.

i know this is a kinda lame question, im not a noob so do flame me i just dont know this one. how do i adjust my idle and if that doesnt fix it what could it be?