Advice on engine (mis)alignment and a few other queries!

[cameron.mitchell]

Hi everyone, I am new to the forum and this is my first post so hope it is pitched correctly. I have embarked on a new build based on the 5 series donor version. Have made some progress but when test fitting the E39 engine I ran into some issues. To get the engine in I had to remove the alternator and it seems to sit seriously off centre - about 7.5cm! The air intake also sticks out over where I think the engine cover will sit and it interferes slightly with the brake servo on the other side. I have added some photos in my profile but would very much appreciate some steer on how to overcome this and if, like me, you think it could be down to the engine mounting brackets being the wrong size?
Also, any advice on radiator expansion bottle sizing and installation would be great.
Cheers
Cameron (not Furnival)

[CosworthCabrioLee]

Re: Advice on engine (mis)alignment and a few other queries!

Hi Cameron first of all welcome to the forum, hope you find it useful,
That engine certainly looks large which engine is it ? To my knowledge there are 4 cabrio's running the m50 engine and several sportsters and I know this is a tight fit. If you have a look on the link page at Simons cabrio build he has pictures etc also Mike Garner has pictures of his M50 install.
I am sure the BMW chaps will be along in a minute

[cameronfurnival]

Re: Advice on engine (mis)alignment and a few other queries!

HI Cameron (not Furnival!) I looked up some details on this and found a pic of MIkes alternator bracket. He has an excellent series of pics on flikr - I know its a cabrio but there will be many similarities. For example reverse theair intake to get it in
here...

Alternator Fitted by Mike's Marlin BMW Cabrio, on Flickr

[Mike]

Re: Advice on engine (mis)alignment and a few other queries!

Hi Cameron (both of you!)

As posted, I have fitted ( shoe-horned!) a BMW M50B25TU (with Vanos) into a Cabrio, which has a smaller/tighter engine bay than a Sportster, and so have met some of the problems you will come up against. This is a similar engine to the one you have chosen, albeit your engine appears to be the later M54 with Dual Vanos, which has a wider more elaborate and complex Inlet manifiold: and I have to say may cause you additional serious ECU issues to resolve - (I hope you have the entire donor wiring loom!)- I believe this also has electronic throttle control?

First question is - What do Marlin recommend for this installation? Have they installed this engine in to a Sportster?, - or is any other builder currently building a Sportster with a similar engine?

The recommended installation of my M50, in to a Cabrio, calls for radical surgery on the Inlet manifold - cut 75mm out of the centre sections - and rejoin it!:



There are a couple of Sportster builders using M50 engines who have found this is not required in a Sportster, but it has been necessary to reverse the Inlet elbow , to face rewarwards, to ensure it fitted within the side panels.



The Inlet manifold on your M54 engine looks particularly wide. It is possible to change Inlet manifolds across engine variants. From reading about BMW engines some of the boy racers prefer to remove M52 inlet manifold and fit the earlier M50's as the later M52 manifold is more restrictive than the M50 version at high end revs, so delivers less top end power. It requires some conversion parts, but is available from those in the know.This might prove to be the simplest option you could follow?

Marlin also advised moving the alternator to the off side - as shown in the preceding post. I believe they supplied the mounting plate tpo other Sportster customers - but beware - they have often assumed you will fit a smaller lucas alternator, and not the donor's alternator.

All of us fitting the 6 cylinder engine have found it tight, and I certainly had the same concerns that you have expressed. The engine does not fit straight relative to the chassis. I tried three different positions for my engine, but reverted back to the Marlin position, and accepted that there is only 10mm of clearance to my radiator, and the same between the gearbox and the firewall. I think Sportsters do have more room to play with front-to- back. Similar to you, my engine is very close to the radiator/nose cone mounts, and the servo, on the off side.

You asked about an expansion tank. This is a current issue over on the Madabout kit car site.

http://www.madabout-kitcars.com/forum/showthread.php?t=3535

I have chosen to make a new expansion tank which has been fitted on to the top of my bulkhead. I calculated water expands by around 4% when heated to 100 degrees, so with 10 litres of coolant I needed a minimum of 400mls above the top of my radiator level to ensure it will always remain full.

[IMG]
Expansion/Header Tank by Mike's Marlin BMW Cabrio, on Flickr[/IMG]


If you would like more photos of current builds, try the following build sites. None of them has the newer engine that you are using, but many of the issues have been the same:

http://www.flickr.com/photos/58068042@N07/

http://www.flickr.com/photos/marlinbuild/

http://www.flickr.com/photos/mikes_bmw_marlin_cabrio/

There are other very good Sportster build sites, using M20 engines at:

http://www.flickr.com/photos/peters-bmwmarlin/ - don't worry that the first few pages are of a Royale Sabre, Peter has moved on to his second kit car project, but has an excellent site on his very nice Sportster.

Robin Martin's equally impressive M20 Sportster

http://myweb.tiscali.co.uk/martinclan/

Patrick Short's very nice M20 version

http://www.msportster.co.uk/

An other Cabrio build, with very useful ideas, is Simon Gregory's

http://www.flickr.com/photos/marlin_bmw_cabrio/with/5820450315/

[Mike]

Re: Advice on engine (mis)alignment and a few other queries!

Hi Cameron - again!

Peter Lister has a Hunter with an Inlet manifold which we think may be from an M52:



As this fits in a Cabrio, it will almost certainly fit in a Sportster. You may have the room to face the air intake rearward, but then use a U-bend to bring it forward facing, rather than into the Passenger footwell.



The shot below shows how tight my engine is to the bulkhead, 10mm of clearance on the nearside below the battery, and the angle it sits at relative to the chassis:

[danny_nelson]

Re: Advice on engine (mis)alignment and a few other queries!

Hi Mike, I thought Peter Licence had a blue V8? not that it matters who the owner is the photo says all that is needed.
Danny.

[Mike]

Re: Advice on engine (mis)alignment and a few other queries!

Hi Mike, I thought Peter Licence had a blue V8? not that it matters who the owner is the photo says all that is needed.
Danny.

Sorry Danny - You are quite right. The Silver Hunter shown previously belongs to Peter Lister.

[cameron.mitchell]

Re: Advice on engine (mis)alignment and a few other queries!

Thanks guys! Really appreciate the fast response and comprehensive info you have given me. I am told the engine is an M52 so hopefully less issues there?????. The air intake solutions look feasible but the one that concerns me the most is the alternator - I don't have the machinery or the skills to get into chopping out sections and re-joining or making brackets and re-engineering things so I think it will be a case of trying to shuffle the beast around a bit and creating some space! I will go through all the material, links etc taht you have provided and will give you an update asap.

Cheers for now and thanks again

Cameron

[b_caswell]

Re: Advice on engine (mis)alignment and a few other queries!

Noticed in WH Smiths today November Kit Car mag has an article on kits with BM engines. Dont know how helpful it would be, didnt read it fully I was in the way!!

[cameron.mitchell]

Re: Advice on engine (mis)alignment and a few other queries!

Hi Ben,

Indeed, a relally helpful article for me as it refers to all the BMW engines being 'slant engines' that sit at an angle of 30 degrees! Not sure how this varies when installed into a Marlin compared to an original BMW but its encouraging to say the least. I have also ordered the back issue which has an article on the E36 engines.

Cameron