M50 / M52 / S50 manifold group buy?

[ste]

I can only see these engine conversions getting more and more popular. The engines are getting cheaper and cheaper - I bought my M52 for £400 with all the loom, EWS, ECU etc - that's the price of a chip and a cam for an M20... M50s pop up for £250 and the engines are so much more refined than the M20 it's a no-brainer in my book.

I see the exhaust manifold being the largest stumbling block for the conversion. Everything else is available off the shelf as a genuine BMW part.

Basically when doing the conversion, you have a few options for the manifold.

1) Hack up and re-weld the existing log manifold. This loses you power/ torque/ economy and negates a large chunk of the point of doing the conversion. You're talking Counciltastic.

2) Have a custom manifold made for £1600+

My idea is to get a group buy together so I can approach a company to make a batch of, for instance, 10 bespoke manifolds for a discount price. I'll supply my car to them as the guinea pig. This will be with the larger rack coupling for an e36 rack conversion. That way it will fit if you do the e36 rack conversion but still fit if you keep the e30 rack.

Now I'm asking for numbers to see who this would appeal to. If I get enough numbers I'll get a firm price and then we can think about deposits.

Depending on numbers involved I'd be willing to invest a large amount of money to span paying for the manifolds to be made and you lot paying when you receive the finished articles. But to do that I'd require some commitment first!

So, who's interested in the final piece of the M50 conversion jigsaw? Stick your names below and we'll take it from there.

[Brianmoooore]

Any idea of final price?

[ste]

I think we'd be aiming for about £800. Won't know fully until I can get some rough numbers.

anyone interested?

[ste]

Ok just had a very interesting phone call.

If we get 5+ on board these will be £480.

That's for a proper stainless steel banana 6 branch based on the E36 M3 Evo manifold but modified to fit an e30 shell with or without the e36 rack conversion!

So who wants a top quality bit of kit at a bargain price?

[Geeman]

Bloody hell, that's cheap! So if you get 10+ orders, the price may drop even further...?

I'm not in the market just yet for this, but I wish I was. Good going my man! Quality.

[Ziggy]

Blimmin 'eck! I'm interested & I wasn't even considering it before!

[Jhonno]

this is for M5X's the S50 one is very different

who would be doing the manifolds?

[ste]

Are you sure the S50 is a different fitment?

I'll have my M52 install to compare to Ian332iSports S50 install (he lives 2 mins from me) - we think the manifold should fit both.

The only issue I think may crop up is the S50 head being 'deeper'. If the exhaust ports are nearer to the inner wing than an M5x we may then have an issue.

Obviously it'll be tried out first!


BTB will be doing the work:
http://www.racecar.co.uk/btb/

[Jhonno]

the manifolds themselves are very different.. if these are suitable for an S50 in an e30 then i could be very interested esp if they will maybe release a few ponies or stop you losing any with modifying the original, and sound as good as the one they do for the m20

yet to cost up modifying the origonal one tho (not something that should really be done at home imo) will be following with interest..

it should be said tho apparently its difficult to produce a generic manifold due to so many variables, its quite an individual thing..

[stevetigger]

I'm interested but not just yet! Just finished my conversion, so very skint!

[ste]

I'm aware they are different - the M50 and M52 ones are rubbish which is why these will be based on the S50 egual length primary manifold.

it should be said tho apparently its difficult to produce a generic manifold due to so many variables, its quite an individual thing..

In what way?

The constants are e30 shell, M50 family engine. They'll also be made to clear the coupling needed for the e36 rack conversion, by default ensuring it clears the normal steering coupling.

Naturally, if it fits on a RHD it'll easily fit a LHD car.

What other variables are involved that restricts use of a generic manifold and demands a bespoke product?

yet to cost up modifying the origonal one tho (not something that should really be done at home imo) will be following with interest..

As a guide, BTB wanted £2,500 to build a bespoke one off in stainless.

[DanThe]

What about the rest of the system?
Would this be based on a three piece exhaust system? ie manifold and frontpipe combo?

[ste]

That would be the plan DanThe.

I'll probably get them to make me a whole system, but the plan will be that the manifold will be just a straight bolt on to whatever system you have, at the usual joint at the bottom of the downpipes.

Having said that, anyone doing a conversion probably won't retain a standard system, you'll need a larger bore to prevent strangling the engine.

[DanThe]

it should be said tho apparently its difficult to produce a generic manifold due to so many variables, its quite an individual thing..

In what way?

The constants are e30 shell, M50 family engine. They'll also be made to clear the coupling needed for the e36 rack conversion, by default ensuring it clears the normal steering coupling.

Naturally, if it fits on a RHD it'll easily fit a LHD car.

What other variables are involved that restricts use of a generic manifold and demands a bespoke product?

Engine mounts and arms would need to be confirmed, I have seen a few conversions using M20 mounts and spacers.
Also the M20 arms can be used with spacing

[ste]

Good points - I thought everyone used the e28 M5 mounts.

[DanThe]

I used the M535 mounts



Not a lot of movement at all

[stevetigger]

I used the E34 rubber mounts!

[DanThe]

Different mounts shouldnt make too much difference TBH,
its when spacers are added to change the angle of the engine

[ste]

Any takers yet?

[Jhonno]

i am concerned bout the small fitment differences and the affect on power on an s50 atm.. big power difference between the engines, so requirements are different...

[ste]

What do you mean by effect on power on an S50?

They are genuine BMW stainless S50 manifolds that have been modified to fit in an e30 shell.

These manifolds have hydroformed curves that no manifold maker in the country can copy as a mandrel bender can't produce curves of this type. So even going to BTB, giving them £2.5k for a bespoke manifold for your car won't buy you a manifold as good as this.

I will be supplying BTB with genuine BMW S50 manifolds, they will modify them to fit. Once we have a product that fits both my M52 installation and Ian332iSport's S50 installation BTB will make a template to use to produce further manifolds.

You're quite near to me Jhonno and welcome to pop over and view progress once I get stuck in.

[ian332isport]

Ste,

Put me down for one if we can get it to work on my S50 properly.

I've never been that happy with the rear manifold on my engine. I was going to visit BTB again at some point to get the last of the Hayward & Scott bodge work removed, but they were going to charge more than £480 to do it.

Jhonno,

I believe an S50 manifold will bolt straight up to the M50/52 cylinder head, so fitment should be okay. As Ste mentioned above, the only problem doing a manifold for both M50/52 & S50 is the wider head on the S50. This may cause clearance issues further down, but this would all be looked at

Cheers,

Ian.

[jmc330i]

Id be interested, depending on the results from Ians car.

Any idea of a time line? Ive just picked up another set of manifolds and was going to start modding soon, but if these are going to be available then I might wait.

[Jhonno]

ah shit, im thick.. misunderstood what was happening

what about if i supplied my own manifolds? would that be the plan?

may be a little confused still.. but way i know see it, it'll be a modified original BMW S50 manifold? yeah?

looking to get my s50 in asap, gotta get it done before end of summer, just lookin for somewhere to actually swap the engines over atm..

very interested in this.. keep me updated n i'll pop over n have a looksie

[ste]

Yeah you can supply your own S50 manifold, not a problem at all and it'll obviously then be less than £480.

[jaistanley]

In that case I'm very interested too as I have to source a manifold or have mine modded to fit.

I'm installing the s50b32 from a zmroadster into a 318is using the steering rack from the zmroadster too.

What time scale are we looking at? I hope to do the conversion over the next 2-3 months. Is this too soon? You might want to use my car as a mule if it's already in pieces. Dunno.

Jai

[Jhonno]

any ideas on cost supplyin my own manifold? also time scales..

plus does anyone need a 4,5,6 manifold section? got a spare one, flexi joint it broken but might be of some use..

[ian332isport]

plus does anyone need a 4,5,6 manifold section? got a spare one, flexi joint it broken but might be of some use..

Is the 4,5,6 manifold section from a 3.0 or a 3.2 ?

If 3.2, I'll take it.

Cheers,

Ian.

[Jhonno]

erm.. pass.. didnt realise they were different to be fair you got a pic of what a 3.2 one looks like?

it just came with the bulk of stuff i bought

[ian332isport]

erm.. pass.. didnt realise they were different to be fair you got a pic of what a 3.2 one looks like?

it just came with the bulk of stuff i bought

They are very similar, but I believe the 3.0L header pipes have welded joints in the middle of some of the pipes. On the 3.2 they are all one single piece. I'm not sure if the pipe size is the same or not.

Any chance of a picture ?

Cheers,

Ian.

[Jhonno]

i'll get a pic in a bit.. just bout to walk the dogs

[Jhonno]

[ian332isport]

It does look very much like a 3.2. What sort of figure are you looking at ?

Cheers,

Ian.

[Jhonno]

Er £60 to pay my uni leccy bill

[ian332isport]

Er £60 to pay my uni leccy bill

Call it £50 and I'll collect from Brighton