Calling all S50B32 engines

[Danny_boykk]

Do you have a 1st gear limiter than limits power before 5000 rpm? Because my friends e36 m3 evo does apparently something do do with an electronic nanny / 6 speed box?

[tomson]

If its an evo (3.2) wouldnt that then be a S52?

[maxfield]

S52 is American based engine on the M52.

[Danny_boykk]

Can anyone help

[ian332isport]

Do you have a 1st gear limiter than limits power before 5000 rpm? Because my friends e36 m3 evo does apparently something do do with an electronic nanny / 6 speed box?

I've read this before, but certainly don't have anything like this on my car. There's no way for the ECU to know you are in first gear, so I don't see how it can limit power in 1st only. The ECU certainly knows when you are in gear, but not which one.

If its an evo (3.2) wouldnt that then be a S52?

Common mistake. As Max has pointed out, the S52 was the 3.2L engine fitted to US spec E36 M3's. This is basically a large bore M50/52 with lumpy cams and only makes 240bhp. As good as the engine is, it's no 'M' engine.

The correct designation for UK/Euro spec E36 M3 engines are S50B30 for the 3.0L, and S50B32 for the 3.2 Evo.

Cheers,

Ian.

[Danny_boykk]

What gearbox you running?

[ian332isport]

What gearbox you running?

Standard Evo 6 speed.

[Danny_boykk]

So am I, it must be in the e36 ecu somewhere. Please can you help me out Ian, you must be a clever fella fitting an engine to your e30 from another car.

Its so bad on all evos that 3.0 m3's are quicker off the mark!

Remapping doesn't solve the problem either apparently

[old_skool]

Could the ECU not read the speed impulse signal from takeoff until the clutch switch is activated and arrange it's maps that way Ian?

[Danny_boykk]

I am desperate here, people on e36coupe.com are useless apart from a turbo brown he knows his stuff.

[old_skool]

What year is the car?

Why are you so desperate?

[Danny_boykk]

1997

I am getting beaten off the lights by a 3.2 TT audi. I know its quattro but still in 2nd gear m3 should have it?

[Danny_boykk]

Could the ECU not read the speed impulse signal from takeoff until the clutch switch is activated and arrange it's maps that way Ian?

Is there a way to reduce this speed signal or something, but then again wouldn that cause engine / fuelling problems. I am so confused atm.

[jason90m]

yea, mine does the same. (doesnt feel like full in first gear low rpms)....but it definately rocks in second and third. 98 euro 3.2 with zf 5spd. jason

[ian332isport]

yea, mine does the same. (doesnt feel like full in first gear low rpms)....but it definately rocks in second and third. 98 euro 3.2 with zf 5spd. jason

With a 5 speed box, the ECU won't even know you are in gear or not. I suspect you don't have the clutch pressure switch either.

In this case, there is no way for the ECU to know what is happening with the gears or the clutch, yet it apparently introduces a limit in first gear only. I just can't see how this is possible. I know mine certainly doesn't do it, and the ECU is totally standard.

Ian.

[Danny_boykk]

This may sound dumb but could it be a mechanical defect i.e. spinning up the heavy dual mass flywheel?

It is definately in first gear and apparently bmw did it for some sort of cheap traction control / protect the fragile 6 spd box. Could it calculate gear from the revs and current speed?

[tubby17s]

i was told that full power is not delivered in 1st gear as most car owners would not be able to control the power in fisrt gear...

how this works i do not know.

would it be relative to the rpm vs road speed? figuring out what gear you would be in to pull those figures?

Josh

[GermanGorilla]

Hi,

A couple of points which always seem to get lost.

The 3.0 E36 M3 is about the same performance as the 3.2 E36 M3.

Although the S50B30 only has single Vanos, it runs a different set
of ratios in its 5 speed Getrag 265 /5 Gearbox.

Thus when you use the 5 speed gearbox with the S50B32 as in the
ZM's the Vanos does not open until around 4500 rpm.
Thus as the engine '' comes on the cams'' its gearing is not optimised
until second gear is selected, where say allowing for a 2500 rpm rev drop,
at a red line of 7950 rpm the engine is now still on the Cams,
ie over 4500 rpm and pulls like a train all the way through second
and so on up through the box.

The 6 speed box being the Gertrag 265/6 has a very short first gear, so
when used with the S50B32, although the Vanos opens at the 4500 rpm
mark, the revs drop of a lot quicker, and sometimes second gear is not
selected until the Vanos has 'retarded' and the engine is off cam.
This is caused by first gear being very short, lots of revs but the feeling
that the car is not going anywhere.
Pulling more revs and getting the engine back on the cams is only a very
short period, but that short period of being off the cam effects overall
performance.

Thus if you run a S50B32 with 6 speed box, any diff ratio above 3.73
becomes a bit pointless for a road car.

I have run the the 3.91 with the above and for the road it was not much
use.

I believe that the gearing, and diff ratio combined with the
Vanos is what makes people belive that they are being ''restricted''
as not saying it does not exist, but sure somebody would have posted
something somewhere about it by now.

Regards,

The Gorilla.

[Danny_boykk]

Gorilla,

In that case why does ian not feel the restriction in his 6 speed box S50B32 and I do with the exact same setup in my e36. Ian are you running a 3.91 diff? whilst mines stock at 3.11 or whatever the stock e36 evo diff was.

What has to be done to change the diff to 3.64 say and keep the LSD function.

[buster]

i still have the 3.91 lsd and my first gear is near enough useless,but it has no limiter appart from the normal one.
And i have tested this when doing a burnout before a timed 1/4 mile run.Mine is also 3.2 with 6 speed.
I will change to a 3.64 lsd when i can.

[tomson]

[quote="ian332isport

If its an evo (3.2) wouldnt that then be a S52?

Common mistake. As Max has pointed out, the S52 was the 3.2L engine fitted to US spec E36 M3's. This is basically a large bore M50/52 with lumpy cams and only makes 240bhp. As good as the engine is, it's no 'M' engine.

The correct designation for UK/Euro spec E36 M3 engines are S50B30 for the 3.0L, and S50B32 for the 3.2 Evo.

Cheers,

Ian.[/quote]

Oh i see, im learning about the S50 every day it seems-and really enjoying it!

[Demlotcrew]

Dont quote me on this but Ian is running 3.15 final drive.

And im not sure if any E36 does have a ratio of 3.64 you can use the CWP from a E30 but not in the Evo as the diff is specific to that car and i dont think its compatible with any other CWP.

The actual size, mouting and connection is different on the E36 3.2 Evo diff to that of any other E36 model.

HTH

[buster]

Dont quote me on this but Ian is running 3.15 final drive.

And im not sure if any E36 does have a ratio of 3.64 you can use the CWP from a E30 but not in the Evo as the diff is specific to that car and i dont think its compatible with any other CWP.

The actual size, mouting and connection is different on the E36 3.2 Evo diff to that of any other E36 model.

HTH

Ian is using a 3.64.

[Demlotcrew]

Buster i have a mint (almost new only 1500miles) 3.25lsd if you're interested?

Or is that no good for a six speed box?

I know the m coupe has a 3.15s for the five speed (BMW could not fit the six speed into the trans tunnel)

[ian332isport]

Dont quote me on this but Ian is running 3.15 final drive.

And im not sure if any E36 does have a ratio of 3.64 you can use the CWP from a E30 but not in the Evo as the diff is specific to that car and i dont think its compatible with any other CWP.

The actual size, mouting and connection is different on the E36 3.2 Evo diff to that of any other E36 model.

HTH

Ian is using a 3.64.

Correctomundo

[GermanGorilla]

Hi,

Danny_BoyKK- Ian runs the 3.64 rear diff, with 17'' wheels and I am
guessing 225 40 profile tyre [611 mm O/D].

In first gear at say 7750 rpm, with a 3.64 diff you will do
max 37mph on a 611mm diam wheel / tyre combo.

Allow for 2-2500 rpm drop on changing gear, and you will
still be on the cams at 5150 rpm so when going into second
at say 5000 rpm doing 34-36 mph you can then pull
all the way to 7750 in second gear which will take you just past the
magic 60 mph, ie 62 mph in 2nd, and your still on the cams.

If you run say a 3.25 Rear diff, while you will increase to 41 mph at
7750 rpm, you will take around 1/2 second longer to due to the
gearing, but can then pull 68 mph in second.

So while the 3.64 diff is quicker for the 6 speed Getrag box, when you
use the 5 Speed box, with the S50B32 engine,
then at 7750 rpm with the 3.25 diff you will be doing 47 mph in first
and then 82 mph in second with only one gear change.

So by the time both reach around 80mph, there would be
almost nothing in it, due to the 6 speed box having to incurr 2 rev
drops as opposed the 5 speed boxes 1.

From there on up they are quite evenly matched until around 145 mph
when the 6 speed box with 3.64 diff at 7500 in top will pull max 177 mph
and the 5 speed box with the 3.25 diff at 7500 in theory is max 200 mph.

This is why the gearing is so critical, and combined with the Vanos, being
far more critcal on the Dual Vanos S50 B32 engine, I think that some
E36 M3 Evo's run 3.64 ratio diff which makes them a much nicer drive,
than the standard 3.23 evo ratio.

Hence why Ian does not hit this percieved ''limiting''.

Swapping diff on the ZM coupe is easier than the E36 M3 / Evo, due to
the ZM using the E30 diff arrangement which the E36 does not.

A well known modification on the E46 M3 if running 19'' wheels is to use
a 3.91 diff, makes the car so muck quicker on acceleration.

Regards,

The Gorilla.

[jamie325isport]

I thought Ian was running a 3:91 diff and 215 tyres?

[jamie325isport]

Im probably wrong though

[maxfield]

You are wrong, he mentions he uses 3.64 in this thread.

Germangorilla, you certainly know your stuff.

[Danny_boykk]

Rear tyres on mine are 245/40/17 (eagle F1's)

How would I change my 3.23 to a 3.64 and still maintain the LSD function. Does it have to be opened up and change the pinion or something - not that I even know what that is! I notice motorway speeds would be ~ 3000 rpm in 6th gear so not too bad.

[maxfield]

Take the original diff out and replace it with another diff, no need to open it up.

[Demlotcrew]

Take the original diff out and replace it with another diff, no need to open it up.

What other diff would that be? The evo diff is specific to that car and wont accept any other type from any other model of E36?

You would need to change the rear subframe and prop from a 3.0l car for it to work. (im guessing only here never done it myself)

[maxfield]

Looks like you would have to open it up then...

Or do that ^^

[jamie325isport]

You are wrong, he mentions he uses 3.64 in this thread.

Didnt see that my bad

[Danny_boykk]

If I open the diff up what exactly has to be changed / will I be able to do it in a few hrs with instructions from you knobbers