BMW E21 327i (second racetrack video)

[croma_man]

thanks, my mate is putting the engine together, atleast here I have the best bmw tuner and mechanic for my friend in our country.

we'll see how this will work with the "old" motronic ECU, plan is to do before winter a few trackdays, then during the winter, ITB's and standalone ECU to pull out of the engine what it can do.

[Jeroen]

Nice work, adjustable cam wheel and all. Just looks funny how some of the thread ends were not removed and connections not cleaned up, I'd rather have that sorted before putting her back together.

Motronic should do ok with a little (rolling road) remap.

[croma_man]

Intake manifold bolts and exhaust manifold bolds are coming new, as I finish the port matching job on the engine and the manifold. So valve polishing, porting and port matching was done by me, as I have a few polishing and grinding skills left, other is done by my friend.

All the bolts for the rods, head, bearings,head gasket and other gaskets...were bought new original BMW parts, only part not BMW are the Goetze piston rings but they are the best you can get aftermarket. Pricy, but in the end, I think worth the money.

[croma_man]

if i'd not learn before how to pee, i'd do that right now in my pants

Engine is running, the original E21 5 speed transmission is on, flywheel 4.5kg works like a charm, water piping and a few details and we are off at the end of the week

[Mihajlo]

Kick ass! Congratulations! Any video coming soon?
It does not have to be a wanton drive. garage one would be as good...

[nas80]

Is the flywheel alloy?

What sort of power do expect to make?

[croma_man]

Is the flywheel alloy?

What sort of power do expect to make?

flywheel is original machined down on CNC to that weight, the same lightened flywheel from the M20 is already 2 months in a M52 tuned car, works with no problems on sight.

Power? Don't even got a clue. People write strange numbers when it comes to the stroked M20 engines...

and some more pics, yes yes, we like pics

[Jeroen]

Lovely!

[croma_man]

Lovely!

thanks, is this everything I need for the speedo to work? From the tacho to the gearbox?

The old speedo cable is nowhere to find.

http://bmwfans.info/parts/catalog/E21/S ... ing_parts/

number 3 ?

[Jeroen]

If your gearbox has a speedo connection and the gears are in there and undamaged, all you need is the speedo cable indeed. Take the version for the 5-speed box as it is slightly longer (373 071).

[croma_man]

If your gearbox has a speedo connection and the gears are in there and undamaged, all you need is the speedo cable indeed. Take the version for the 5-speed box as it is slightly longer (373 071).

thanks,

I bought a while ago the original E21 M20 gearbox, sadly first gear goes up and not down but still, better than e30 gearbox without speedo gear.

[nas80]

I got my m20 flywheel down to 6kg and couldn't see where else to take material from ? do you have a pic of this flywheel?

really nice job on that engine and yes pictures are awesome.

are you going to run rubber flex disk on your gearbox? i got rid of mine and replaced it with a solid one, gear changes are much more snappy now, and no vibration. anyway I also have the speedo problem - I use the zf box from the m3. what I did was get e28 speedo, mount it in the speedo housing and im going to use the GPS speedo box from Dakota digital to drive it. very simple and easy job this way.

you can actually get speedos that have gps sensor built in to them but you lose original look,

[croma_man]

i found a pic of the M52 and the M20 flywheel, you can see where it lost a few pounds Have to search if I have a pic of the whole flywheel.



about the rubber flex disc, I don't know if I understood you right, did you mean the hardy disc?

[nas80]

ah I see it, you went right up the starter ring gear. I told my machinist to leave a few mm behind that for strength.

i am planning to turbo my car at one point so might be ok with a 200 but maybe not so with 400. years ago when I had an rx7, a tuner called Dragon performance built a drag car and used a stock flywheel, twin rotor with 700hp totally destroyed it, i believe it destroyed the gearbox but it actually could have gone through the tunnel and hit the driver - he was lucky.

I think you will be fine though, if it survived an m52 your probably going to be ok with an m20?

hardy disk? is that what you call it? its either called a flex disk / guibo / rubber thing. Its that object with 6 holes that goes in between prop and gearbox

I found that after having lots of fun the torque just rips it apart, even a decent branded one doesn't seem to last long so I had a solid disk made up instead. maybe that's why they put larger ones on the m3 / 328 and bigger engine bmws?

[croma_man]

yes yes yes, we talk about the same piece. For now we just changed the "rubber thing" catchy name

mine already on the M20B20 was schredded, on the M52 he went over 2-3 pieces already, so yes, I think this upgrade awaits me.

Do you have any pics? How is it when driving, no rattling or vibrations as the transfer is direct without rubber?