Engine from automatic to manual gears

[kabeldjiata]

HI, i have a Porsche 944 with M44/07 engine and manual gearbox, I want to replace the engine with another removed from car with automatic gearbox( m44.03), so can I use bellhousing, clutch, and flywheel from the old motor, is it this conversion possible? Thanks

[Cocacolakidd]

All of the parts are interchangeable - The main differences are the clutch assembly. The Automatic Clutch Damper differs so you will have to use a Flywheel, Clutch Plate, Pressure Plate, and Throw-out Bearing from a standard trans. If your car is a Standard Shift just use the set-up you have already on the car with the Auto trans Motor. Also if I remember correctly the bell-housing may be different on the Auto Trans set-up, as there is not an opening for the clutch fork - use the standard shift bell-housing with the change over, along with the clutch fork, pivot pin, etc.

Replace the motor and not the bell-housing and internals.

[porschetub]

As already outlined in the last reply it's pretty straight foward, I converted 89 2.7 auto into 85 2.5 manual,while you are there do the mod on the bellhousing,it involves cutting a section out for easy speed/referance sensor removal later.
Takes 20mins to do and you will pat yourself on the back latter if you do these sensors @ some stage.
There is a tread somewhere on here outlining the procedure.

[kabeldjiata]

Thank you, what kind of head gasket I must use for pre 1985.5 engine, i have 951-104-374-02 but, my mechanic says that there is difference in cooling hole.

[9FF]

...while you are there do the mod on the bellhousing,it involves cutting a section out for easy speed/referance sensor removal later.

Takes 20mins to do and you will pat yourself on the back latter if you do these sensors @ some stage.

There is a tread somewhere on here outlining the procedure.

The cut out mod is for early cars using the early starter. Don't do it if you have replaced the starter on your early car to a later one or if your car is 85.5+

[krystar]

that headgasket is what's listed in pelican catalog for 83-88 944's

[krystar]

...the cutout mod is on the top of the bellhousing....starter is on the bottom. don't see how related?

[9FF]

...the cutout mod is on the top of the bellhousing....starter is on the bottom. don't see how related?

Porsche issued a technical bulletin a while back about this. Cutting out the bellhousing where the sensors are can cause poor starting and a clunk from the starter motor when it catches. The factory cut out the 87 models then issued a tech to retrofit a sleeve in there to fix the problem.

Basically cutting out the sensor bracket causes bad readings to the sensor eminating from the starter motor.

I thought this was common knowledge but I'll try and dig out the tech bulletin and post here.

[9FF]

Tech bulletin as promised and a link to the problems you'll get if you cut out the bellhousing:

Problem described here: Loud clunk on start up - Rennlist Discussion Forums

Factory Technical Bulletin here:

[Cocacolakidd]

I have looked all over for the part numbers to be able to order these shielding parts/updates - Does any one know the part numbers ? Does Porsche publish them
someplace ?

Several years ago I cut out the hole to make a slot for the Reference Sensors/ bell-housing easier removal and every once in a while do have a condition of pre-ignition (This article finally made sense of all of that).

[krystar]

ah. so it's sensor EMI. interesting

[9FF]

ah. so it's sensor EMI. interesting

EMI yes that's it, I was trying to think of the TLA that described the problem. The early cars (-85.5) used a larger starter motor which must have had better shielding and prevented EMI. So the cut out mod can be done on these cars only unless a later starter was fitted. Hope that all makes sense.

[porschetub]

I've had no problems,sorry but whats "EMI''?.
Hope I haven't made a mistake by doing this as it seemed to be fairly common practice
I also carefully opened out the sensor holder holes so the sensors won't stick up in there.

[MrTibbs]

I have a vague idea of buying an auto and converting it to manual using the running gear from my car which I've just totalled.

I seem to remember some issue about the wiring on automatics having something that stops it from being started while in drive that you have to sort out. Is that right or have I mis-remembered?

Mike

[porschetub]

Sorry didn't read the service letter so I know what emi is now.
I have earlier bellhousing with later motor so I should use the larger (later?) starter then.
By the way 9ff thanks for pointing this out.

[9FF]

I've had no problems,sorry but whats "EMI''?.

Hope I haven't made a mistake by doing this as it seemed to be fairly common practice

I also carefully opened out the sensor holder holes so the sensors won't stick up in there.

Electro-magnetic Interference. The magnetic field generated by the later starter motor interferes with the sensor signal if the bellhousing is cut.

The symptoms are your starter will turn slowly (labor) before finally catching and sometimes you will hear a clunk from the starter when it catches.

If you are not having any issues you're fine.

[9FF]

Sorry didn't read the service letter so I know what emi is now.

I have earlier bellhousing with later motor so I should use the larger (later?) starter then.

By the way 9ff thanks for pointing this out.

The early starters are larger and don't have this problem. It only affects 85.5+ starters which are smaller.

[v2rocket_aka944]

bellhousings are the same manual or auto

[porschetub]

If thats a question no they aren't the same for starters there is no provision for the clutch slave cylinder,best to use a manual one.