Recently bought a 325i cab off here which has had a recent engine rebuild and was also fitted with a lightened flywheel and a Z3 shortshifter.
I use the car as a daily and find that whilst in traffic it gets a bit annoying keeping the revs high enough to stop the car from stalling, and at idle it feels a tad bit lumpy, which may be due to the lightened flywheel I'm guessing.
The gears are also abit stiff for my liking too, too notchy and way too stiff for my liking!
What do you guys recommend? Would going back to standard make the drive smooth and pleasant? I'm not looking for quick off the line performance or anything, just a nice drive.
Thanks!
Lightened Flywheel & Shortshift back to standard?
Moderator: martauto
-
German-Whips
- E30 Zone Camper
- Posts: 1157
- Joined: Wed Jul 14, 2010 11:00 pm
- Location: Berkshire
The car doesn't cut out but I find that it needs a bit more revs than I would of expected to move it forward whilst sitting in traffic.leeparkes wrote:A light fly shouldnt make the car cut out.
If I slowly lift the clutch to the biting point I can feel it shuddering before it starts moving off, it's quite hard to explain.
There's quite alot of traffic to and from work and it can get pretty tiring and annoying quickly.
I shall say no more 
-
e30rapidic
- E30 Zone Newbie
- Posts: 161
- Joined: Wed Jul 01, 2009 11:00 pm
- Location: Raleigh NC USA
a lightened flywheel will certainly affect the idle smoothness. I put a lightweight flywheel in with my S50 swap and had the idle bumped up to 900 rpms for that very reason. Nobody can tell.
A cheap fix would be to adjust the throttle cable at the throttle body; bump the idle up just a bit to see if it smooths it out.
As far as the shuddering in the clutch....is it oem? If so its been overheated or old. Or it may be a puck style clutch. My stage 2 clutch shudders in heavy traffic like that.
A cheap fix would be to adjust the throttle cable at the throttle body; bump the idle up just a bit to see if it smooths it out.
As far as the shuddering in the clutch....is it oem? If so its been overheated or old. Or it may be a puck style clutch. My stage 2 clutch shudders in heavy traffic like that.
-
hongkongfuey
- Mad-tango-geezer
- Posts: 3304
- Joined: Fri Jun 08, 2007 11:00 pm
- Location: portsmouth
Don't adjust the throttle cable or throttle body. Check engine and wires , serviced, plugs cap motor etc. Mine has very light fly and have no trouble in traffic
if there wern't people like me,
with cars like mine,
who would you put down to make yourself feel better?
with cars like mine,
who would you put down to make yourself feel better?
-
German-Whips
- E30 Zone Camper
- Posts: 1157
- Joined: Wed Jul 14, 2010 11:00 pm
- Location: Berkshire
I don't think the idle is low or anything, and the idle is certainly not rough or terribly lumpy either.
I'd say that 900rpm idle would be too high comparing it to my current idle. Mine currently idles at about 600 rpm.
It's just that I can feel an ever so slight lumpiness whilst in traffic, and having to rev it when moving off, being a heavy convertible doesn't help either. I'm guessing that having a lightened flywheel means having a decreased rotating mass which means that you have less momentum to keep the engine spinning, and at lower revs, (idling at 600 for example) the engine hasn't got enough momentum to keep it turning over smoothly?
Is that correct?
I also notice when I change to 2nd gear the car surges because the revs are not high enough? The engine doesn't surge, but it feels like I didn't have enough revs so it sort of surges until it picks up enough revs for the gear, after which it's smooth.
Seems like this flywheel is too light for a heavy cab with a possible 318i diff I'm guessing?
I'd say that 900rpm idle would be too high comparing it to my current idle. Mine currently idles at about 600 rpm.
It's just that I can feel an ever so slight lumpiness whilst in traffic, and having to rev it when moving off, being a heavy convertible doesn't help either. I'm guessing that having a lightened flywheel means having a decreased rotating mass which means that you have less momentum to keep the engine spinning, and at lower revs, (idling at 600 for example) the engine hasn't got enough momentum to keep it turning over smoothly?
Is that correct?
I also notice when I change to 2nd gear the car surges because the revs are not high enough? The engine doesn't surge, but it feels like I didn't have enough revs so it sort of surges until it picks up enough revs for the gear, after which it's smooth.
Seems like this flywheel is too light for a heavy cab with a possible 318i diff I'm guessing?
-
German-Whips
- E30 Zone Camper
- Posts: 1157
- Joined: Wed Jul 14, 2010 11:00 pm
- Location: Berkshire
Pete can you let me know when you have a slot free so I can bring the car in for a check over and some maintenance?
There's a few niggly issues which need sorting, including a slight whine from the engine bay which is intermittent and engine speed dependant.
There's a few niggly issues which need sorting, including a slight whine from the engine bay which is intermittent and engine speed dependant.
-
leeparkes
- Married to the E30 Zone
- Posts: 9538
- Joined: Thu Jan 03, 2008 11:00 pm
- Location: Black country
You can bump the revs up by fooling the ECU into thinking the aircon is switched on.
Brianmoooore wrote:There is a small plug hanging off the engine loom near the ECU plug. Connect the black/purple wire in this plug to 12 volts ignition switched, preferably fused, live. This will be a wire that has green as its main colour.
Cypriotgeeza wrote:I done both my mates in my old 318is
felt so proud,even tried it with a E30 325i and got put in my place..
As HKF said, a lightened flywheel on an M20 will not effect the smoothness of the idle.
As Pete says, the idle speed is too low @ 600 rpm.
The low idle speed is the cause of your lumpy idle, sort the idle speed out and it will smooth out.
As Pete says, the idle speed is too low @ 600 rpm.
The low idle speed is the cause of your lumpy idle, sort the idle speed out and it will smooth out.
-
e30rapidic
- E30 Zone Newbie
- Posts: 161
- Joined: Wed Jul 01, 2009 11:00 pm
- Location: Raleigh NC USA
I beg to differ...I have a 11 pound flywheel on mine and it will idle rough as anything with the stock idle speed. There is a night and day difference in the smoothness between the two chips and their respective idle rpm's.
I've run the lightweight flywheel on M20 2.5's, stroker 2.8's and an S50. It affects them all.
I've run the lightweight flywheel on M20 2.5's, stroker 2.8's and an S50. It affects them all.
-
daimlerman
- **BANNED**
- Posts: 15968
- Joined: Mon Feb 27, 2006 11:00 pm
- Location: Grumpy Old Man
Stiff or notchy gearchange could be down to the gearbox oil.
I found that a change to ATF transformed the shift,particularly with a cold 'box.
I found that a change to ATF transformed the shift,particularly with a cold 'box.
Youth is wasted on the young.
I've had lightweight flywheels on 318iS' and 325i's and I've not found them any harder to drive in traffic or that the idle has been affected. Sounds to me like there is another underlying issue somewhere.
Short shifters are a more personal preference, I like the Z3 1.9 but found the Z3 2.8 a bit too short and notchy until the gearbox warmed up. Try changing the gearbox oil and see how it is after then.
Short shifters are a more personal preference, I like the Z3 1.9 but found the Z3 2.8 a bit too short and notchy until the gearbox warmed up. Try changing the gearbox oil and see how it is after then.
Well you can beg to differ all you like but i have fitted plenty of 6kg flywheels to M20B25 engines with no adverse effects.e30rapidic wrote:I beg to differ...I have a 11 pound flywheel on mine and it will idle rough as anything with the stock idle speed. There is a night and day difference in the smoothness between the two chips and their respective idle rpm's.
I've run the lightweight flywheel on M20 2.5's, stroker 2.8's and an S50. It affects them all.
In fact, there is an M52 E30 right outside my house now with a 6kg M20 single mass flywheel and the idle is rock steady.
-
German-Whips
- E30 Zone Camper
- Posts: 1157
- Joined: Wed Jul 14, 2010 11:00 pm
- Location: Berkshire
The car is definitely idling at around 600rpm, which is too low.
After having done some research on here, I have read that a good way to diagnose the problem is to check for any air leaks first and foremost.
One of the checks suggested was to take the oil filler cap off with the engine running to see if that makes a difference to the idle?
I removed the oil filler cap and the engine died down and cut out momentarily after removing the cap.
Does this suggest and air leak or does this suggest the problem lies elsewhere?
After having done some research on here, I have read that a good way to diagnose the problem is to check for any air leaks first and foremost.
One of the checks suggested was to take the oil filler cap off with the engine running to see if that makes a difference to the idle?
I removed the oil filler cap and the engine died down and cut out momentarily after removing the cap.
Does this suggest and air leak or does this suggest the problem lies elsewhere?
sort the idle out, might be the idle controller or incorrectly set throttle switch or butterfly or all of the above. or someother issue like vacuum leak
A lightweight flywheel will make a good functioning ICV more important as it needs to "catch" the engine more effectively and prevent it stalling as the engine slows quicker under no load.
ive seen the stock mornoic idle well with the alloy flywheels from JBR which are lighter than you can safely take a stock one down to so it is not root cause, but wont help the matter
A lightweight flywheel will make a good functioning ICV more important as it needs to "catch" the engine more effectively and prevent it stalling as the engine slows quicker under no load.
ive seen the stock mornoic idle well with the alloy flywheels from JBR which are lighter than you can safely take a stock one down to so it is not root cause, but wont help the matter
E30 325is with M20B31