Running reports

[MartinClan]

I have been watching this thread with interest - not that I am likely to change my engine installation now 90% of the way through the build.

So what is the advantage of the M50 over the M20 - is it purely that it is a more modern engine? For the guys like me that have already installed an M20 I can't help thinking it would be a lot of hassle changing to the M50 - all those brackets to make, exhaust and fuel systems to sort, electrics to do... Would it not be a better solution just to change to an after market engine management system like Megasquirt?

Just sittin' on the fence for a bit here ;-)

Robin

[Mike]

Originally Posted by MartinClan

I have been watching this thread with interest - not that I am likely to change my engine installation now 90% of the way through the build.

So what is the advantage of the M50 over the M20 - is it purely that it is a more modern engine? For the guys like me that have already installed an M20 I can't help thinking it would be a lot of hassle changing to the M50 - all those brackets to make, exhaust and fuel systems to sort, electrics to do... Would it not be a better solution just to change to an after market engine management system like Megasquirt?

Just sittin' on the fence for a bit here ;-)

Robin

Robin
The M50 has 24 valves with variable inlet valve timing, making it more torquey (is there such a word?) at much lower revs. It is smoother, quieter, and more fuel efficient, and delivers 192BHP. The M52 with twin Vanos is more refined still, and the 2.8 with an M50 inlet manifold will achieve 220BHP.
For me it was not about absolute power but, low down revs torque. i just happen not to like engines which sound like screaming banshees - hence a nice slow revving straight six. I did consider a V8, but the BMW will certainly not fit the Cabrio engine bay, and the Rover appears to only deliver 150BHP, and very low fuel consumption.
I gues it is horses for courses - know what you want from your engine, and then choose one to suit your own well defined criteria.
As you say.........all very interesting. has anyone used the M52 in any type of Marlin?
Mike

[MartinClan]

Originally Posted by Mike

has anyone used the M52 in any type of Marlin?
Mike

What about this one? http://jward.info/Delivery%20of%20th.../target20.html

Looks interesting anyway.......

Robin

[peterux]

Oh dear, now you have really got me interested!! I wonder if that is Jeremy who posts on here?

You see i really enjoy the challenge of solving problems and now Mike has confirmed the M52 electronics are really complicated you've proabably made me even more interested in having a go!!

It's a bit of an illogical sequence but i'll explain my thought process.
It starts with a rather worn and noisey (tappets) M20 that has already done 170k miles. As most of you know, it's a 2 litre version and when I first drove the car it felt like a rocket, but you soon want more!
So i started looking into refurbing the head. Probably £400+ gaskets etc for a decent one but then the crank might be worn or the pistons, etc, etc. The parts for a refurb also add up to £200-300.
So I started browsing for a second engine but who knows if any other M20 would be better than mine The BMW's drive so well most engines are high mileage and the low mileage ones could be clocked or unknown condition.
So then i start looking at M50's thinking there will be little difference and an easy swap. Then Patrick puts me straight and points out I need the gearbox as well since the M50 is mounted at a different angle.
He goes on to comment on the M52B28, so I took a look at Wikipedia and oh boy what an engine! It won all kinds of awards and I could go from 130bph to 190bph to 220bph - yikes!

It's all an academic exercise at the moment as I still haven't finished my car and haven't had the time to even drive it in the last four weeks! (House DIY, holidays, etc!)

I've already decided that if I was going to embark on this course I would buy a complete car to get all the necessary parts. Mike's input above has confirmed that is needed because of all the electronics. I broke the news to my other half that I was just thinking of swapping the engine but haven't owned up to thinking of buying another whole car and practically re-buidling the Sportster (well, she would only worry!)
Whole cars are dirt cheap for what you get and I think with the road tax going up soon they will get even cheaper.

Like I said, just a paper exercise at the moment...........(...but I've already invested in a Bentley manual - oh dear...)

[Mike]

Peter

If you go back to page 3 of the Sportster/Cabrio there is a thread called "Unhappy owner". He has bought an M3 engine to go in his kit, but was looking to sell it. I know he was offered £3k for the engine gearbox wiring etc. Dont know if this is in the dream budget, but what a car it be..............

[peterux]

Originally Posted by Mike

Peter

If you go back to page 3 of the Sportster/Cabrio there is a thread called "Unhappy owner". He has bought an M3 engine to go in his kit, but was looking to sell it. I know he was offered £3k for the engine gearbox wiring etc. Dont know if this is in the dream budget, but what a car it be..............

Thanks, Mike, but even in my dreams that would be too much!

peter

[Patrick]

There's a chap on E30 Zone selling an M52B28 crank and 130mm con rod. That plus a M20B25 and you'll have a nice 2.8ltr

Build it take the current engine out and your sorted for a winter project

A quick call to Ant @ A-Tech and the ECU can be easily sorted for the higher capacity with a new chip.

Not sure on the power but should end up around or above 200bhp with a wedge more torque as well.

[MartinClan]

Also seems to be someone selling a complete 2.7 engine - just rebuilt. Hmm

No - mustn't be tempted - must finish the car first.....

Robin

[Mike]

Peter

How about this one, at half the price?
http://cgi.ebay.co.uk/BMW-E46-M3-S54...d=p3286.c0.m14
Mike

[Patrick]

noooice engine The updated ones put out some where in the region of 340bhp Won lots of awards as well.

M54/S54 bring their own difficulties such as electronic throttle that you need to deal with. It's also a bit of an a issue with VANOS engines as I don't think megasquirt is up to dealing with variable valve timing yet which means stock ECU and EWS (but as I understand it its possible to turn that off).

There's a number of TVR V8's on ebay right now, they would awesome.

[peterux]

I seem to have really started something here....

Like Robin said, I really need to finish the car first and spend my money on getting it painted!
I was down at the Marlin factory (barn) today to collect my windscreen, hood frame, hood and to get some vents cut in my top bonnets.

So I now have lots to do!


Mark told me he is considering offering the Audi 2ltre turbo engine as an option on the Sportster which he reckons is good for 220bhp

[Patrick]

your not the only one that needs to spend money on paint first tee hee. But it's fun to dream / waste hours on end looking at engines

I only did the engine rebuild at the beginning of the year due to the crash and waiting forever on new parts. Glad I did it as it was an interesting project never having taken and engine to bits. I'll be sticking with the M20 for a while to come yet realistically!

[peterux]

Originally Posted by Mike

Peter

I did a lot of research into the engine options for my Cabrio, before deciding to go for the M50 2.5.
My decision was based on:
As relatively new design as possible
As efficient as possible
Electrically simple

Patrick is right about the M52. When BMW replaced the M50 with the M52they had to meet tougher emission/insurance regulations. They then had to increase the cc upto 2.8 to achieve the same power output as the M50 2.5
By simply changing the inlet manifold from the M50 2.5 on to the M52 2.8 will take the BHP up to 220BHP. These are advertised on ebay and I have seen them make £100 each. I have one which I may well sell in the future when I am sure my modification to my manifold has proven successful - we have to chop 75mm out of the manifold to fit it in the Cabrio - not sure if you'll have to do the same in a Sportster - I guess you may have to as ???? has a purple Sportster fitted with the M50 and he has fitted a special home made glass fibre elbow, but I think this is believed to restrict the air flow at the top end.
Have a look at my site on flickr to see the drastic action necesary to make it fit a Cabrio.
I chose not to go down the M52 route as the engine electronics are tied in to the cars central locking system and even the electronic key- so if you do go down this route be prepared to either adopt the entire M52 wiring loom, or make sure you know a good BMW electrician who can reprogram the chip to blank off the ingition switch, door lock sensors and all the others before the engine will work.
If you are prepared to take on the electronics of the M52 it should be a lovely engine with twin Vanos (variable valve timing on both inlet and outlet valves) the M50 has only single Vanos on the inlet.

Let us know what you finally decide to do, as this is really interesting.

Regards
Mike

Does anyone here know if the e46/M52 uses the same engine mounts as the e36/M50?
Also, any details of the mods required to the ecu or e46 wiring diagrams on the web?

thanks

Peter

[Patrick]

I'll see what I have on my CDs re: E46 wiring

[peterux]

Originally Posted by Patrick

I'll see what I have on my CDs re: E46 wiring

thanks

Peter

[Patrick]

I found a wiring diagram cd that covers the E46, just sorting something out, will email you later

[peterux]

Originally Posted by Patrick

I found a wiring diagram cd that covers the E46, just sorting something out, will email you later

Hi Patrick,
thanks for looking but I bought a DVD off fleabay the other night,

Peter

[peterux]

Ok, so I've gone and done it.

I blame the weather as it's been too cold to finish fitting my windscreen and hood.
I'd been watching on eBay an M52 2.8 litre engine out of an 1998 e46 complete with all ancillaries and exhaust system.
It turned out the guy selling it was only 20 mins drive away, so when he listed it again for the third time and no buyers, I called him and went to see it. After about 10 mins I was stuffing crisp £20 notes into his hand and the deal was done.
My son and I went down to pick it up today and here is a picture just after we got it back in the garage.



there are some more pictures on my Flickr site here..........

http://www.flickr.com/photos/peters-bmwmarlin/

........just got to figure out the wiring now........

Peter

[Patrick]

very, very nice

[MartinClan]

Hi Peter

So - will that bolt straight onto the M20 gearbox?

Robin