6 replies to this topic

[minilee94]

seen this bmw head conversion kit anyone know if its any good how hard is it to fit
what stuff do i have to do to my 1275 block lik overbore etc

http://www.ebay.co.u...=item2c47c67d1c

[benjy_18]

lots of things you need to do for it to fit.

pocketed pistons for valve clearances,
redrilled headbolt holes in the block (old ones need to be blocked off)
oil feeds, water feeds need looking into

best to buy the specialist components build diary and read through and also have a good read on efiminis forum

IIRC the 16v heads only fit the larger overbores (1380 etc)
so to put it on a 1275 youd be looking at the 8v twin cam head

[ibrooks]

It's overpriced for what you are actually getting IMHO.

The water feeds are fine as they are. The block's oil feed to the head needs "pulling" slightly to one side. You need to have proper blanks put in the head stud holes and welded and then new holes drilled. You need to convert the engine to belt drive timing. Plus other odds and sods.

There are a couple of mods that need to be done to the head itself for the oil returns and to seal the end where the timing chain was.

You can fit a 16v head on an 850 so there's no reason to go to silly overbores. An 8v head will fit without valve pockets if dished pistons are used.

It's not a difficult conversion. There are a couple of jobs that need to be done by a proper engineering shop but in the grand scheme of things they are pretty minor.

Getting the build book is a good idea as it lists the stuff step by step which can also allow you to get bits piecemeal wherever they come up cheapest (like the Ford "SOHC/Pinto" timing tensioner and verniers.

Iain

[govig]

Motor Works is a good company to deal with. I have used them for years for BMW bike stuff.

[Sprocket]

IIRC the 16v heads only fit the larger overbores (1380 etc)

No. 16v or 8v heads 'fit' on any 'large' bore block in any overbore sizes from 1275 to 1399

[Sprocket]

It's overpriced for what you are actually getting IMHO.

It is infact a very good price since you get all the parts off the BMW Motorcycle that you need to start the coversion. You might be lucky and buy a complete engine for less, but you are then risking it being scrap since the latest 8v engines are now 21years old.

You need to convert the engine to belt drive timing.

This is correct. You'll need a conversion kit from th likes of Force Racing or Specialist Components

There are a couple of mods that need to be done to the head itself for the oil returns and to seal the end where the timing chain was.

Correct.

You can fit a 16v head on an 850 so there's no reason to go to silly overbores. An 8v head will fit without valve pockets if dished pistons are used.

No one has yet fitted a 16v head onto a 'small bore' block and the 8v head creates its own set of challenges. I have yet to understand why anyone would go to the effort and great expense (and trust me it is an effort and a great expense) to consider using a small bore block with these heads, you will get far better results for less effort using the large bore block. Valve pockets will be required in ANY piston irrespective of dish or number of valves. I use an 18cc dish piston, which is as extreme a dish as you'll get, and I still needed to have valve cuts.

It's not a difficult conversion. There are a couple of jobs that need to be done by a proper engineering shop but in the grand scheme of things they are pretty minor.

That all depends on whom is carrying out the conversion.

Getting the build book is a good idea as it lists the stuff step by step which can also allow you to get bits piecemeal wherever they come up cheapest (like the Ford "SOHC/Pinto" timing tensioner and verniers.

Iain

The timing gears and pulleys are only a small part of the overall conversion, you would still need the seal plates. You can mak these yourself, but its not a 5 minute job with a Black and Decker. I wouldn't be using the old profile tooth patern of the Ford Pinto, there are better ones out there.

Hope that helps a little

[Sprocket]

Motor Works is a good company to deal with. I have used them for years for BMW bike stuff.

I concur

They are well aware of the Mini scene now and are very accomodating for what others would see as bizarre requests lol. Their prices are very reasonable too.