Interesting Sportster and Cabrio/Hunter Engines

Mike · #1 15th June 2012, 19:13

Thought you might like to see this photo from Ian Kitchener of his Sportster. Apparently it was a Marlin's demonstrator in 1997, and has a bored and stroked 2.8l BMW engine.

Ian has passed on this information:

Re: The engine
The Sportster was built by Marlin cars in 1997 using only brand new parts and was their demo & show car. There is a great feature and review on the car in the 1997 September issue of "Which Kit".
The engine is a BMW 6 cylinder 2.5 litre that was bored and stroked to 2.8 litre. The fuel delivery system is via "Lumenition" fuel injection comprising of three throttle bodies and K&N air filters. The engine has the Lumenition Cal 660 competition engine management ECU. The vehicle has a specially manufactured twin side exhaust system which produces a very throaty rumble at tick-over. When the throttle is opened, very, very loud!!!. Extremely fast vehicle with instant pick-up. Great fun.

Looks great Ian.
Thanks for passing on, and allowing others to see what can be done.
Mike

peterux · #2 16th June 2012, 08:05

Hi Mike and Ian,

that's a cool engine installation

Thanks for sharing with us all.
It must have been a big investment by Marlin back in '97 to fit those throttle bodies and custom electronics on top of boring and stroking the engine. It looks like an M20 so I wonder what crank they used? Maybe it's a standard 2.5 crank but with large pistons and shorter rods?

I also spotted from Ian's profile picture that he has a rather interesting curved windscreen.
He tells me that he... "believes it was fabricated by the second owner. The frame is all polished s/s and the base matches the curve of the scuttle, The great benefit is it extends full width and is fastened to the body on the sides. Sides look very "Sevenish". On the top of the frame there is a preformed groove that would accept a "boltrope" from a hood if fitted."

If you click on Iank's name you'll see a picture of his car.

...peter

Mike · #3 16th June 2012, 20:31

And here is another one.......does anyone recognise this engine? 6 Cylinder 2.8
It is in Malcom Platt's Sierra based green steel wheeled Sportster, and really goes well with the style of his car.

Clue
It is not BMW, or Ford!

Answer next week unless anyone knows......................

Patrick · #4 17th June 2012, 08:01

No idea on the above, I know jag's used straight 6's!

Dunno how long the Ireland engineering stroker kits have been around but that might have been an option in the top engine. Or it could be a mix / mod of the eco engine BMW made bored with custom pistons. Wonder which head it has on there.

jeremy · #5 17th June 2012, 08:35

Could it be a 1980's nissan L series engine, used in very early skylines?

Mike · #6 17th June 2012, 15:59

Very impressive Jeremy.
It is apparently a Datsun 280Z, with a Jaguar inlet manifold and twin 2" SUs.

jeremy · #7 17th June 2012, 16:39

This does really look well, brings a certain period authenticity to the car.

peterux · #8 17th June 2012, 16:59

As Mike has started a thread of interesting engines, I thought I'd add this one again here....

Marlin Sportster by marlinpeter, on Flickr

Triple carbs (Webers?) and coil pack ignition. It's a BMW M30 engine but I don't recall what size, possibly 3.5 litre. http://en.wikipedia.org/wiki/BMW_M30

...peter

Mike · #9 17th June 2012, 17:31

This Green Sportster is now owned by Dr Derek Kitchener (Father of the owner of the Red Sportster below with the stroked 2.8).

Peter

I think you should post a current one of your too, as it is a special, being stroked and bored to 2.8, but with the standard Inlet plenum. What injectors have you used, and have you altered the ECU mapping?

Mike

Quote:

Originally Posted by peterux

As Mike has started a thread of interesting engines, I thought I'd add this one again here....

Marlin Sportster by marlinpeter, on Flickr

Triple carbs (Webers?) and coil pack ignition. It's a BMW M30 engine but I don't recall what size, possibly 3.5 litre. http://en.wikipedia.org/wiki/BMW_M30

...peter

Patrick · #10 17th June 2012, 18:37

That M30 was nice

Mines a 2.8 stroker:

M52B28 crank
M20B20 conrods
282°/272° dbilas cam
Schrick valve springs
M20B25 head, pistons, bottom end and intake manifold
BTB 6 branch manifold
Big bore throttle body
BMC carbon airbox
Off the peg 2.8 chip from Ant @ A-Tech

It does need mapping properly - thinking about adding a miller maf conversion, M30 injectors and a custom map.

Full build: http://www.msportster.co.uk/m20b28-engine-build

Mike · #11 18th June 2012, 15:13

Should have made the title "Interesting Sportster & Cabrio Engines"

This may be of particular interest...............

This is Peter Lister's Hunter with a BMW M3.

This looks like an M52 engine to me, though I thought M52s had double vanos?
If it is M52, does this mean Marlin solved the OBD 11 security problems?

If it is an M3, why does the Engine cover not have M Power on it? The inlet manifold is not what I expected, but it ties in with this below.....

Mike

Mike · #12 18th June 2012, 16:09

Is it possible to edit a thread title?

peterux · #13 18th June 2012, 20:01

Quote:

Originally Posted by Mike

Peter

I think you should post a current one of your too, as it is a special, being stroked and bored to 2.8, but with the standard Inlet plenum. What injectors have you used, and have you altered the ECU mapping?

Mike

OK, mine is similar to Patrick's since we followed the same 'recipe book' but I did use a few different ingredients to keep the cost down!

I started with a standard 1988 325i engine.

328i crank from an M50 or M52 engine (not sure which?)
M20B20 conrods
Standard diameter short skirt Mahle 325i pistons (my originals were long skirt)
New standard profile cam
New rockers and rocker shafts but original valves and springs
Standard inlet and exhaust manifolds
Standard throttle body
325i cylinder head
M20 injectors (cleaned and tested professionally)
Bosch W7DCR spark plugs
Vernier camshaft pulley
Escort Mk2 RS2000 Alloy radiator (and Escort hoses)
New thermostat housing and 'stat (as I didn't want any cooling issues)
ECU is chipped with a copy of an Alpina C27 chip
New oil pump, water pump and all bearing shells, gaskets, seals, etc.
4.1 small case diff.

Fuelling seems to be about right with very smooth power delivery albeit the idle is just a bit on the high side at 950 rpm. (Engine has so much power, I can pull away in first gear with no right pedal!!)
I am very pleased with the result!!

Assembly continues... by marlinpeter, on Flickr

M20B28 Installation complete by marlinpeter, on Flickr

morris · #14 19th June 2012, 11:56

Hi Mike,

That manifold doesn't look like M3 or M52. Late M52s did get double vanos and the plastic valve cover just before the change to the M54 so could be one of those. The other thing I think it could be is a US spec M3 engine though as they were not the same as the S50/S52s we had in europe. They were much more like an M50/M52 that had been tuned up and had capacity increased as the euro engines didn't meet the US emissions rules. They did have an M power engine cover though but apart from that, looked externally just like a single Vanos M50, even down to the flakey silver paint on the valve cover

[EDIT] just noticed your second photo of the engine in a production car. I reckon that the sportster engine is a late M52B28 with the US M3 manifold

MartinClan · #15 19th June 2012, 12:46

One thing I noticed with all the photo's of the go-faster engines is that they all seem to have the standard Metro servo. Err - I wonder how well they stopped?

Robin

chaterpedal · #16 19th June 2012, 17:11

mine stops quite well but takes a bit of effort, I have bought the new unit from Mike as has my son, Ian,, look forward to the change.

Patrick · #17 19th June 2012, 18:39

S50 engines have individual throttle bodies which is a clear give away between standard and m engine

Yep as said US M3 engines were actual M52 engines with different cams / optimised intakes (ie non restrictive like the M52B28, the M52B28 benefits massivle from M50 manifolds) which is why euro spec M3 engines are sought after there.

http://328compact.co.uk/m50-intake-and-bbtb - big gains without the restrictive intake from 190 to 236 with a rolling road map.

morris · #18 19th June 2012, 19:34

Actually now having looked at the photos again on a brighter monitor at home I can see that the engine is single vanos, not double like I originally thought which makes it much easier to ID as a straight forward M52B28 or M52B25. I knew the M52 intake runners were thinner than the M50s but I'd never noticed the tapering before.

Mike · #19 20th June 2012, 07:43

So does this mean the cognoscenti have settled on it being a US M3 with M52 B28 - not late, as it has only single vanos - with a US Inlet manifold - less restricted than we see on European M52s, and is likely to have special cams too?

Quote:

Originally Posted by Patrick

S50 engines have individual throttle bodies which is a clear give away between standard and m engine

Yep as said US M3 engines were actual M52 engines with different cams / optimised intakes (ie non restrictive like the M52B28, the M52B28 benefits massivle from M50 manifolds) which is why euro spec M3 engines are sought after there.

http://328compact.co.uk/m50-intake-and-bbtb - big gains without the restrictive intake from 190 to 236 with a rolling road map.

Mike · #20 20th June 2012, 07:51

Quote:

Originally Posted by MartinClan

One thing I noticed with all the photo's of the go-faster engines is that they all seem to have the standard Metro servo. Err - I wonder how well they stopped?

Robin

Hi Robin

There is a link here. The photos I have posted are all from owners who I have been in touch with through the Dual servo project. I think we all recognise the Metro servo just did not provide sufficient extra brake assistance, and the Dual servo fills the gap.

There are still a few more interesting ones to come - a Supercharged V8 Cabrio being one of them ........with an advised top speed in excess of 120mph - "and just starting to go light"!

Regards
Mike