M42 stroker build begins

[i8ur911]

You guys went from a stock M42 clutch/FW to a lightened M20 setup and did NOT notice a difference?! I must be sensitive or something lol. I noticed a big difference in peppiness (as well as obnoxious tranny rattle at idle and while engine braking particularly in 5th gear).

When I did my M42 hot rod, I used a flywheel from a 2002 tii (and clutch) lightened it further and cut it down to accept the M42 ring gear.  I needed to use the "323" throw out bearing.

WOW what a difference.  In fact it was so light (and tough) that the car wanted to die most times when coming down to idle on its own.

WHICH M20 flywheel do you use in your concept?  Clutch?  Bearing?

Jenn

I used a standard single mass M20 flywheel (resurfaced and lightened), M20 clutch, M20 TOB, M42 flywheel "spacer" and M20 starter.

NO NOISE AT ALL YET :knock on wood:

[bmwman91]

19lb injectors

You should consider the stock ones over 19# ones as stockers are 21# injectors. There is a lot of hearsay on the web, but the stock M42 injectors are 21# and I have OEM data from both Bosch and the spec sheet for the 13-button OBC coding plug that agree. Per Metric Mechanic, the stock 21# injectors are good for a max of ~190bHP, and that's running a harsh duty cycle. They have me using 24# units for the "205bHP" engine that they built for me.

The injectors that I am running are EV1 style bodies with the EV6 style outlet (4 small holes). They are Bosch PN 0 280 150 461. These should provide you plenty of head-room while still allowing for pretty good PWM resolution at lower flow rates.

[i8ur911]

Thanks for the info. I always thought M42's used 17lb injectors. I'm hoping to still be in the 160whp range with this set up so I'd rather have "a little more injector" than not enough. I'll have to think about sticking with the stockers.

Thanks!

[bmwman91]

For 160whp, you will probably want to beef up the injectors. Stockers can do it, but they will probably have a limited lifetime since you will need to run 90%+ duty cycles at high load. I'd consider the 24# ones.

[MLM]

Im jealous of your Dbilas!

I think the cams are made for factory pistons. Of course, always measure before starting the engine!!

You are correct sir. No additional pocketing necessary. Already confirmed with machine shop too

Ah awesome thanks guys. I had always eyed up these cams but held off thinking it would involve all sorts of piston machining. That will make your build that little bit easier !


 

[wazzu70]

Ah awesome thanks guys. I had always eyed up these cams but held off thinking it would involve all sorts of piston machining. That will make your build that little bit easier !

We should all get these cams Its my next upgrade planned....but I need to get the engine up snd running as-is now first!

[i8ur911]

Not engine related, but I bought some GC coilovers today. Couldn't get happy with my H&R set up. Also bought a Z3 1.9 rack and a set of smoked front turn lenses.

Engine update - machine shop says I'll have the head next week. Hopefully the Dbilas kit will show up then too

[i8ur911]

Z3 rack is installed. First impression.....holy shit! This should be the first upgrade to any e30. The steering feel is amazing. Heavier than the standard e30 rack and VERY direct.....point and go

Also installed my GC coils with KMAC camber plates. Really nice drop without cutting strut towers, adjusted all the way down in front and almost all the way in the rear.

Need to install my new sump armor skid plate soon.

Dbilas throttle bodies are FINALLY in route......long story......short story is they suck. I'm hoping the product is MUCH better than the people.

[wazzu70]

Glad to see things coming along!

[colin86325]

I agree, steering rack is a great upgrade.  I'm using one from a 2005 330i and I love the responsiveness!

[i8ur911]

Guess what arrived today........

Pics to come tomorrow

[318is91turbo]

throttle bodies? this is an awesome thread

[i8ur911]

[i8ur911]

[mabeer]

Man, you're easy to hate I'm really enjoying your build.