B18FT Flywheels

480_rocket · Post by **480_rocket** » Sat Sep 29, 2007 12:42 pm

I've done a lot of searching and can't come to a real answer of the type of flywheel fitted to the B18FT, and the number of teeth. Does anyone have any photos showing the flywheel?

It seems some people have managed to swap the ECUs around and not had any problems, which suggests to me that it either:

a) the flywheels are all the same
b) the EZK somehow detects which flywheel is fitted, which I don't think is possible, and can't see any way it can do that.

Apparantly according to tardis, the pre 1994 turbos had 44-2-2 (which sounds odd because thats Renix style) and later ones had 60-2. Maybe I'm reading tardis wrong?

480_rocket · Post by **480_rocket** » Fri Oct 05, 2007 2:58 pm

YAY!!!!

So, with no reply to this topic I decided to work it out myself. I thought perhaps I could connect my oscilliscope to the Flywheel sensor, but my 'scope can not capture and save the waveform....

So, using the in car PC, I used Audicity to record the signal from the flywheel sensor!

I simple wired up a stereo mini jack to a couple of resistors (100k and 1 meg ohm) to reduce the voltage from the sensor, and fed into the line in.

And from that, you can see missing tooth, and 58 pulses, which is 60-2 flywheel (60 teeth, but two missing). You can also see the compression of the cylinders as this was captured while cranking. From that you can help determine if a cylinder is low on compression. You can also tell where the gap in the flywheel is in relation to TDC, in our case I think its 90 degree BTDC.

In other words, Tardis appears to be wrong.

gltease · Post by **gltease** » Fri Oct 05, 2007 4:12 pm

Now thats what i call using your noodle !!! Nice one.

owen080808 · Post by **owen080808** » Fri Oct 05, 2007 5:55 pm

cooooolness

VanDerGraaf · Post by **VanDerGraaf** » Fri Oct 05, 2007 7:30 pm

Great work there!

yknot · Post by **yknot** » Fri Oct 05, 2007 9:24 pm

i swapped a 1993 b18ft engine(blue ecu) and gearbox with a 1990 one(orange ecu), ecu's not changed, only the flywheel sensor and works perfectly... so the flywheel teeth position and numbers are the same.

480_rocket · Post by **480_rocket** » Sat Oct 06, 2007 5:49 pm

Bring on Megasquirt time me thinks

I'll have to upload some photos, it fits perfectly into the LH 2.2 ECU, and has a trailing wiring loom to a dummy EZK box, used just to pick up sensor information (Flywheel sensor, TPS, boost solenoid etc).

I've also installed extra ignition coils, so I can hopefully get rid of the original coil, dizzy and HT leads to run Renault COPs (coil over plugs).

Ettore Bugatti · Post by **Ettore Bugatti** » Sun Oct 07, 2007 9:31 pm

Interesting finding!

So 60-2 flywheels were fitted before 1994?

Correct me if Im worng, but there around 6 ignition modules (from Bosch)for the B18FT.
As you said 44-2-2 is Renix, but perhaps Volvo did developed a EZK version for it to converse B18F into B18FT when supplies of B18FT engines dried up?
Not all EZK's are compatible, so I would think that there are B18FTs with 44-2-2 flywheels.

MS is very interesting, but it isn't the holy grail. It supports more features the other aftermarket ecus, but a Renix and LH+EZK is still quite sophisticated.
For example MS is one of the few that offers knock detection, but that isn't fully developed as you would find in the Renix or EZK.
I would prefer a modded Renix over Megasquirt, but my wallet says that Megasquirt is dead cheap and offers unique education experience (aka trouble

)

How did connect it to the PC? Did you split the signal? (Im guessing that the ECU still needs the flywheel signal)

BTW If you make a pickup sensor around plug wire then you can measure, calculate horsepower (logging revs vs time during acceleration)

480_rocket · Post by **480_rocket** » Sun Oct 07, 2007 9:59 pm

Well, it is possible there were EZK versions that need 44-2-2, but it seems that from at least 1990-1996 flywheels were the same. I searched for ages trying to find real info on this, and no one has posted anything to prove there is a 44-2-2 on the turbo.

There are wiring differences between different years of wiring loom on the turbo, so its quite possible swapping ECUs without moddify/changing loom will result in a non runner.

My Megasquirt so far has cost Ã‚Â£105, and I'd have to disagree about it being worse than a tuned standard ECU, because megasquirt supports much more. Injectors can be fired in batchs, you can use wasted spark and best of it it'll autotune the fuel map when a wideband O2 sensor is installed.

We'll see how much trouble the megasquirt is when I try it

owen080808 · Post by **owen080808** » Sun Oct 07, 2007 10:18 pm

can't wait to see an MS B18FT, there just isn't the option to (easily) tune the standard ecu. keep us installed on how much of a pain it is to install

480_rocket · Post by **480_rocket** » Sun Oct 07, 2007 10:43 pm

I only measured that signal while cranking, so flywheel sensor was disconnected from ECU.

Ettore Bugatti · Post by **Ettore Bugatti** » Mon Oct 08, 2007 9:23 am

OK, that's clear!

I will look into the parts catalogue if I can find any new reference to the flywheels.

yknot · Post by **yknot** » Mon Oct 08, 2007 8:24 pm

maybe it's time to put again on track my MS project

.... i bought my MSII in december....

480_rocket · Post by **480_rocket** » Mon Oct 08, 2007 8:45 pm

yknot, maybe you can record data from your flywheel sensor from your 1990 turbo?

shimon340 · Post by **shimon340** » Tue Oct 09, 2007 12:16 am

hello

nice work!

how does this waveform tell you a cylinder is low on compression?

480_rocket · Post by **480_rocket** » Tue Oct 09, 2007 9:19 am

Mine isn't low on compression, so it doesn't show up. But if it did you wouln't see the frequency and amplitude of the signal dropping. You can see on the waveform every 180 degree the signal squishes abit, because the starter motor slows done a little due to engine compression.

shimon340 · Post by **shimon340** » Tue Oct 09, 2007 5:12 pm

would low compression just cause the frequency to drop,longer wavelength,signal strength wouldnt be affected by low compression.... long cranking might begin to drain battery to voltage to sensor drops and output drops accordingly.

nice mod to get the waveform... how exactly did you do it?

sensor left connected to car wiring loom, you added extra wiring to the sensor to connect to stereo jack?

look forward to hearing from you

is audicity special software, expensive?

thanks

shimon

480_rocket · Post by **480_rocket** » Tue Oct 09, 2007 5:45 pm

Audacity is just for recording sound onto a PC! Its freeware. If you listen to the WAV file it makes, it sounds just like the turbo engine cranking, seems to have a distinct sound?

The faster the flywheel spins the more volts it makes, and vice versa.

yknot · Post by **yknot** » Thu Oct 11, 2007 3:37 pm

both flywheels(1990 and 1993 b18ft) are exactely the same! i've compared when i swapped the engines.
rocket, explain me how to record flywheel data.
what's your status with MS?
Florian.

480_rocket · Post by **480_rocket** » Thu Oct 11, 2007 5:08 pm

yknot@ interestting!

MS is built, and I updated firmware and tested seriel link, all good. It just needs to be plugged in really, turn the key and see what happens

Like I said earlier, use Audacity software on PC. Then hook line in on PC to flywheel sensor with a couple of resistors to reduce the signal voltage.