M42B18 to M50B30 Swap

[E30-323ti 66]

On the brake front. Sure some of them may have been fitted with AST but look at the basic parameters of the 328

It was a big jump up from the M 50 325 - 30 % increase in power and similar increase in torque - top speed up from 230 kmh to over 245 kmh with bags of torque low down that make the 325 look feel an anaemic screamer.

In gear acceleration not much short of the 540 V8.

The 328 in manual form (and lets face it we are the anomaly here 80% of European BMW's are Manual) is a performance car and it needs performance standard brakes to match - hence ventilated discs all round.

Inital cars were fitted with 260 kmh Speedo and run a 255 kmh speed limiter which mine should now be capable of hitting.

Are you comparing the M50B25 power to the US M(S)50B30?? or M52B28??

The M50B25 & M52B28 have the same power output 141kw Vs 142kw and torque of 250Nm & 280Nm respectively.

Not disputing a 328 goes better than a 325, but def. not 30%

[conrod 1]

American M3 engine (S52) uses cast iron block, not alloy!

[Guest Spargo]

A 3.73 would be a fun diff with the 1:1 5th

Might get a bit buzzy down the motorway/open road, rev-ing ~3100@100kph and maxing out ~220kph, but hell it would get there fast

what about a dogleg mated to a 3.73 and an M20 ?

[Gus 5]

what about a dogleg mated to a 3.73 and an M20 ?

pure nastiness...with 3.23 LSD and dogleg was at about 5800 rpm @ an indicated 190-200k at end of puke...even on the road the 3.23 is short

[Guest Spargo]

So what diff you recommend? Sounds like I need Darren to source me a longer diff.

[E30-323ti 66]

The dogleg box is a 1:1 5th is it not??

If so a 3.25 should be fine, but Gus's info suggests otherwise (unless he was still in 4th??).

[conrod 1]

I'm running a 4.45 in my car at the moment,and with a 1:1 6th gear it is perfect at Puke! Mind you, it will pull 9000 in top!.........

[Guest Spargo]

Yea thats what I was thinking Glenn, the normal box seemed fine when we chucked a 4.1 in there, but I never got a ride with the dogleg.

I'm sure a 3.7 diff with a 1;1 top would rip

Edit: assuming its a getrag 245/10 gus - Getrag 245/10 close ratio/â€doglegâ€

Gear ratios

1st - 3.764

2nd - 2.325

3rd - 1.612

4th - 1.229

5th - 1.000

It should be doing approx 3262.698rpm at 100kph. I could live with that.

Or if its a 245/11

Gear ratios

1st - 3.764

2nd - 2.325

3rd - 1.612

4th - 1.229

5th - 1.000

Would only get to about 200k's though!

Edited January 11, 2007 by Spargo

[E30-323ti 66]

I'm running a 4.45 in my car at the moment,and with a 1:1 6th gear it is perfect at Puke! Mind you, it will pull 9000 in top!.........

LOL, now thats the business!!!! What height rear tyres does it run?? 610's??

Sam, both sets of ratio's are the same!?!?!

If puke is your regular, bouncing off the revlimiter down the back straight would grow rather tire-some, but fun everywhere else

Mind you some 17's with taller tyres could reduce that problem a bit!!

[Guest Spargo]

Yea i just figured - they are meant to be the same

[Gus 5]

just going by what i used...TBH unless ya tracking, keep ya current box/diff setup

diff engine, boxes will change this obviously

[conrod 1]

LOL, now thats the business!!!! What height rear tyres does it run?? 610's??

650 tyres all round. A standard E30 325i only has enough grunt to pull about 190 down the straight at Puke (even though the speedo will tell you 200) so there is no point gearing it for 240 kph, as given a long enough straight it won't be able to pull max revs in top gear anyway. An E36 M3 Evo will do about 230 kph at Puke, and that is with 320hp. You have to look at what hp your car is making, and gear it accordingly.

[E30-323ti 66]

650 tyres all round. A standard E30 325i only has enough grunt to pull about 190 down the straight at Puke (even though the speedo will tell you 200) so there is no point gearing it for 240 kph, as given a long enough straight it won't be able to pull max revs in top gear anyway. An E36 M3 Evo will do about 230 kph at Puke, and that is with 320hp. You have to look at what hp your car is making, and gear it accordingly.

Thats tall!! What width 250's??

For comparison, I was doing just on 200 down the back straight and 210-ish down the front at Manfield and only needed to use 3rd & 4th, joys of turbo'd torque. This was on road tyres, if it had more grip (and not a muppet like me driving) out of the preceeding corners it would be quicker.

The straights at Puke & Taupo are look rather daunting

With the current diff it's geared for 285k in 5th, but with the E30's stunning aero and 300whp I don't think that would be possible, or a very good idea.

[conrod 1]

looks like the same engine for sale again on turd me- what happened???!!!

http://www.trademe.co.nz/Trade-Me-Motors/C...on-84214591.htm

[318isCoupe 0]

There was some pretty decent evidence given to me by someone who's apparently seen the engine that it is not a genuine M3 engine and most likely a dressed up M50.. someone else appears to have pointed this out in the current auction also, so for now this plan (with this particular engine anyway) is on hold.

Still quite keen to do a swap to maybe even just an M52, but as 3pedals has pointed out.. I need to get the suspension & brakes side of it sorted before I rush into something.

Would probably rather M52>M50B30 US M3 engine anyway in all honesty, as parts are so much more available and as 3pedals has shown, the 47hp power difference can be recovered reasonably easily.

However, would much rather go M54 or S50.

Have another project to finish first though so I don't want too many jobs (and bills) on my hands at once.

Thanks for the help though guys.

[conrod 1]

easy enough to identify, it should be a cast iron block for one (and there were no cast iron vanos engines apart from US ones) and the engine number stamped on the block will be a giveaway too, somebody on this site has posted a link to identify your engine. Still sounds like a good deal, if it is genuine.

[kerrynzl 3]

Hey Conrad! South Africa also did Iron Vanos engines because of their crap fuel . I've got one sitting in my shed [it was matching#'s when I pulled it from the car]

[conrod 1]

I stand corrected! Engine ID number will still tell you what it is. Unless it is an M3 then I would go the 2.8 engine, I sold one about 6 months ago for $2500, nobody was really interested in it at the time though, it ended up being a replcement for one somebody had cooked due to all of the water falling out!...................

[318isCoupe 0]

Hey Conrad! South Africa also did Iron Vanos engines because of their crap fuel . I've got one sitting in my shed [it was matching#'s when I pulled it from the car]

Which engine is it? M50?

I stand corrected! Engine ID number will still tell you what it is. Unless it is an M3 then I would go the 2.8 engine, I sold one about 6 months ago for $2500, nobody was really interested in it at the time though, it ended up being a replcement for one somebody had cooked due to all of the water falling out!...................

I think I'm probably going to go with an M50B25 or M52 swap, or Euro M3 engine.

[kerrynzl 3]

Mines an Iron Block M52B28,

Give Me a txt or call if you wanna come round and have a look. I can get you a M50B25 non vanos if you want one

[318isCoupe 0]

Mines an Iron Block M52B28,

Give Me a txt or call if you wanna come round and have a look. I can get you a M50B25 non vanos if you want one

Would definately be interested to come around and have a look, would you be interested in selling the M52B28?

There's only a minor difference in torque between the vanos and non vanos M50B25 right?

[kerrynzl 3]

There's only a minor difference in torque between the vanos and non vanos M50B25 right?

The non-vanos has longer duration cams to get the same power. the max torque is down slightly but it also needs to rev to 4700 [vs 4200] to get max torgue

the real plus with a non vanos is the BOSCH DME instead of the Siemens unit [the Bosch can be reflashed ]

[318isCoupe 0]

Cheer's for that, when suits you to come around and have a look?

The E36 is getting new brake goodies at around 2:30 tommorow, Mintex 1166 pads for a bit more bite and new fluid. Going to put a new set of tyres on the factory 16's also.

[318isCoupe 0]

Depends on what you want to use the car for and how you drive.

The bigger torque at lower RPM is a real bonus on open road driving, particualrly in B28 form.

You should outline what your goals are then respective parties can chip in their 2c worth and help you can make a totally confused decision and be bagged by at least half the people of the forum, just kidding.

Kerry out of interest what is the lift etc on the non vanos cam VS M52 single vanos, is this an easy way to get more power out of an M52 single vanos?

I drive in a manner that involves getting to the speed limit as fast as possible, not deviating from that speed limit for most corners and planting the right foot hard out of corners that I do slow down for.

Basically I'm wanting a bunch more power low down (the M42 feels dead below 4500rpm/40kph) to get me off the line a fair bit quicker and punch me out of corners in a bigger hurry.

M52B28 sounds about what I want to be honest, but an M50B25 would be almost as good!

Ideally: worked M52 ~ 200hp / stock S50, 5-speed manual, different differential ratio.

But for now, stocker M52B28 or M50 & 5 speed manual would be great.

[BM WORLD 1283]

i have 92 325cia 5spd auto with M50 2.5 non varnos , it was chipped by last owner , and has sleightly loader rear muffler , i am going to convert to 5spd manual when i get around to , but i quite like the power curve comes in with a rush over 4000rpm , sound nice too .

would like a bit more torque like my e28 M535i has , that engine pulls from about 2000rpm quite strong , car only weighs about 40kg more .

i n a straight line drag with a mates M535i thats had , engine had new rings etc, e34 head fitted , chipped and a cam , pretty much neck and neck upto about 150km/h then the e28 just pulls away ,he is still in third gear upto 180km/h .