s50 engined e30's

[NomNomNom]

M50/M52 share pistons and rods. S50 pistons are the same height as M50/52.

I have used M50 block, S50 pistons, M52 crank and rods. I also have taken 0.5mm off the block for a comp ratio of 11.1

I was talking stroke (piston/rod/crank), thought you had kept the M50 crank with stock rods and S50 pistons.

^^^^ So was I.[/quote]

What I mean is "I was talking 'a different' stroke", sorry i'm quite ill with a cold/flu at the moment and perhaps not as lucid as I should be when talking about this stuff

[NomNomNom]

the pistons / rods make no difference at all to the stroke, only where the piston sits in the bore / compression ratio.

The term relates to a half revolution of an engine during which the piston travels from one extreme of its range to the other, so if you fit shorter rods or skim the piston, it changes the stroke...

No it doesn't.. It still travels the same distance, just further down the bore

I'm confused, if you subtract length from the range why doesnt that shorten the stroke? I'm certainly no engineer so forgive my ignorance :/

[Jhonno]

Because the crank dictates the stroke, it follows a circular path of in this case 84?mm dia, the length of the rod and height of the piston merely dictate where in the bore the piston travels this 84mm

[NomNomNom]

hmm right, I see what you're saying now totally, i'm such an idiot at times :/ i've always thought it was the total length of the reciprocating componants gahhh!

[marty325]

out of interest where do the major costs to amount to £6k cost come into this conversion

Ive said it before and I'll say it again, its not just a case of buying an engine, fitting it and driving it away - if it was that simple, everyone would be doing it.

http://www.e30zone.net/modules.php?name ... rsion+cost

http://www.e30zone.net/modules.php?name ... rsion+cost

http://www.e30zone.net/modules.php?name ... rsion+cost

considering that i've been offered a couple of complete e36 m3's for under £2.5k?

Ask yourself why are they under £2.5k. Most in that price bracket will be shagged, tired examples - try costing up an S50 rebuild
Having said that, if I was do it again I would buy an M3 to break, to try and get some money back.

I may be wrong but from what i have read, the main cost is the exhaust manifold at over 1k for this, full system is around 2k i think.

Dave at Fritz is now doing a complete manifold/system for around £1k (M50/52 and S50) - designed and built properly by a local company, it looks very good indeed

It;s definitley a conversion that i'll seriously be considering doing in the future. I'll be starting with my sport, and by the time I sell the bits off the m3 that I don't need the engine and box should only be standing me about £1.5k. Also have a mate who is handy with stainless steel mainfolds. Can the m3 calipers be used as a brake upgrade? and can the sport diff handle the power?

[jmc330i]

Most people on here will tell you not to convert a Sport. Id say get on with it, especially if youre going to keep it - thats what I did with mine.

Can the m3 calipers be used as a brake upgrade? and can the sport diff handle the power?

The M3 calipers will probably take a fair amount of work to get fitted to the E30 front strut - more than is really needed or worth while, when there is BBKs already available. They will fit E30 M3 struts ok, but discs are a problem.

The E30 diff is fine with the power, but for a road car it will only be of use with the E36 M3 evo 6spd box. If you fit the 3.0ltr 5spd box, you will need a diff ratio of around 3.15:1 to have sensible revs when cruising, otherwise 70mph in 5th with a 3.91:1 will be around 4k rpm.

Good luck

[Jhonno]

It;s definitley a conversion that i'll seriously be considering doing in the future. I'll be starting with my sport, and by the time I sell the bits off the m3 that I don't need the engine and box should only be standing me about £1.5k. Also have a mate who is handy with stainless steel mainfolds. Can the m3 calipers be used as a brake upgrade? and can the sport diff handle the power?

Unless he is BMW handy you might end up losing much of the benefit over fitting a tuned 2.8 or built 3.0 etc..

[marty325]

It;s definitley a conversion that i'll seriously be considering doing in the future. I'll be starting with my sport, and by the time I sell the bits off the m3 that I don't need the engine and box should only be standing me about £1.5k. Also have a mate who is handy with stainless steel mainfolds. Can the m3 calipers be used as a brake upgrade? and can the sport diff handle the power?

Unless he is BMW handy you might end up losing much of the benefit over fitting a tuned 2.8 or built 3.0 etc..

He's a cosworth man, hates BMW's but I will NOT pay £1300 for a manifold, there has to be an alternative. This could be the decider on whether to do the project or not

[da4x4turbo]

He's a cosworth man, hates BMW's but I will NOT pay £1300 for a manifold, there has to be an alternative. This could be the decider on whether to do the project or not

This is why the conversion is so expensive dude. The S50 is a highly tuned engine producing 100bhp/litre from the factory. The Exhaust manifold is an integral part of this.

Going for a cheap manifold is a fools game. In the words of Oscar Wilde: "A cynic knows the price of everything. but the value of nothing"

By all means modify the manifold yourself, but be prepared to be disappointed when it only makes 250bhp on the rolling road. It's happened in the past.

[jmc330i]

I will NOT pay £1300 for a manifold, there has to be an alternative.

The Fritz system is around that price, and thats manifold with complete exhaust system. I will speak to Dave tomorrow and find out the exact price.
When you think a decent full stainless system for a 325i can set you back almost £600 and a 6 branch will be the wrong side of £600, the price doesnt seem so bad.

This is why the conversion is so expensive dude.
By all means modify the manifold yourself, but be prepared to be disappointed when it only makes 250bhp on the rolling road. It's happened in the past.

Thats why I ended up with the BTB (only one available at the time). Ive modded 2 sets of manifolds with the help of a specialist exhaust blokey, but without the correct equipment to test it, it was a waste of time.
The one I fitted seemed to work ok, but when I fitted the BTB, the difference was like night and day - and thats both of them with the same homemade exhaust Im running at the moment.

[Rickz]

6k to do the conversion??

I never thought it cost that much, but then surely you might aswell do an m3 conversion because the price to do that isn't far of is it??

[da4x4turbo]

Thats why I ended up with the BTB (only one available at the time). Ive modded 2 sets of manifolds with the help of a specialist exhaust blokey, but without the correct equipment to test it, it was a waste of time.
The one I fitted seemed to work ok, but when I fitted the BTB, the difference was like night and day - and thats both of them with the same homemade exhaust Im running at the moment.

YEah I bought the BTB too. I felt nauseous when it arrived though an I saw how little work was done. But I guess the real money was spent on the back engineering that they had to do in order to meet the power requirements.

I also bought the full BTB system. Luckily I got a huge discount on it as I'd bought the manifold already. It's very very tasty!

[jmc330i]

surely you might aswell do an m3 conversion because the price to do that isn't far of is it??

What M3 conversion?

What conversion do you think we are talking about?

[jmc330i]

I felt nauseous when it arrived though an I saw how little work was done.

TBH, I think if you look at how the primaries were modded up by the head to get the right angles etc, it just goes to show how much work/development actually went into it, not to mention lower down and getting it to clear everything its supposed to.
Having been there and done it myself, I can say its not easy.

Having seen Daves manifold at Fritz now, Im still happy with the BTB, especially with how impressed Dave was with how mine went, even with its homemade exhaust. I do think BTB could of done a better job if they had started a fresh, rather than modding an existing manifold, but then the cost would of gone up no doubt.

I am waiting to see the results of Daves S50, when he finally gets the time to work on it, but I can tell you his M50 went very well with his full manifold and system

[GraniteE30]

which engine would be best if your after big bhp using forced induction, m50 or s50?

[da4x4turbo]

I felt nauseous when it arrived though an I saw how little work was done.

TBH, I think if you look at how the primaries were modded up by the head to get the right angles etc, it just goes to show how much work/development actually went into it, not to mention lower down and getting it to clear everything its supposed to.
Having been there and done it myself, I can say its not easy.

Having seen Daves manifold at Fritz now, Im still happy with the BTB, especially with how impressed Dave was with how mine went, even with its homemade exhaust. I do think BTB could of done a better job if they had started a fresh, rather than modding an existing manifold, but then the cost would of gone up no doubt.

I am waiting to see the results of Daves S50, when he finally gets the time to work on it, but I can tell you his M50 went very well with his full manifold and system

Yeah I agreed with you dude... Very selective use of the quotes there!

YEah I bought the BTB too. I felt nauseous when it arrived though an I saw how little work was done. But I guess the real money was spent on the back engineering that they had to do in order to meet the power requirements.

I'm an engineer, I know there's a lot more to it than a bit of welding!

[jmc330i]

Very selective use of the quotes there!

I'm an engineer, I know there's a lot more to it than a bit of welding!

I know, I realised I deleted the wrong bit but couldnt be bothered to go and change it
I know it was expensive, but over all Im still happy with it - the look on the face of my first Porsche victim was worth it alone

[jmc330i]

which engine would be best if your after big bhp using forced induction, m50 or s50?

I guess it depends what you mean by big bhp?? At a guess, for ease, simplicity and comparative cheapness, Id say M50.

Turboing or S/charging any engine isnt cheap, but starting with an expensive engine to begin with wont help matters, especially when things start melting

[NomNomNom]

Also depends what you want to use it for?

[da4x4turbo]

Very selective use of the quotes there!

I'm an engineer, I know there's a lot more to it than a bit of welding!

I know, I realised I deleted the wrong bit but couldnt be bothered to go and change it
I know it was expensive, but over all Im still happy with it - the look on the face of my first Porsche victim was worth it alone

Awesome! All is good in the shire...!

Yeah I can't wait till I get to drive mine. It's soooo close now it's actually doing my head in! I'm like the proverbial child at christmas!

[GraniteE30]

which engine would be best if your after big bhp using forced induction, m50 or s50?

I guess it depends what you mean by big bhp?? At a guess, for ease, simplicity and comparative cheapness, Id say M50.

Turboing or S/charging any engine isnt cheap, but starting with an expensive engine to begin with wont help matters, especially when things start melting

Say 400bhp upwards for a road legal track car, for example.

[Jhonno]

which engine would be best if your after big bhp using forced induction, m50 or s50?

M50

I am still sceptical about Fritz's offering until I see it dyno'd on a reliable rolling road, (Sheps/Sal/Surrey) not Fritz's.. You can't make a manifold that excels for both M50 and S50, they both have massively different requirements/port sizing etc, it just ain't gonna happen. BMW's M Division will have spent a lot of time and money on the manifold design..

[NomNomNom]

which engine would be best if your after big bhp using forced induction, m50 or s50?

I guess it depends what you mean by big bhp?? At a guess, for ease, simplicity and comparative cheapness, Id say M50.

Turboing or S/charging any engine isnt cheap, but starting with an expensive engine to begin with wont help matters, especially when things start melting

Say 400bhp upwards for a road legal track car, for example.

For track purposes a supercharged/small turbo'd S50 since the throttle response is *much* better, for drag or simply big figures an M50.

Big bhp to me is 500+

[Jhonno]

For track purposes N/A is the way forward..

Turbo'ing an S50 is a pain, due to the high (actually high, not M20 'high') compression ratio

[NomNomNom]

You wouldn't need more than 7/8 psi to get the figures he's after, as you say however the effort is hardly worth it... plus the turbo, intercooler...etc all add weight where you dont want it.

I think an S50B32 which is remapped on a good quality 2.5"+ non-cat exhaust system with a higher volume performance plenum chamber and some more extreme shrick cams wouldn't be far off what he's after and it would be far more usable.

[jmc330i]

I might be a bit late here, but thought Id update this for those that are interested.

I will NOT pay £1300 for a manifold, there has to be an alternative.

The Fritz system is around that price, and thats manifold with complete exhaust system. I will speak to Dave tomorrow and find out the exact price.

The manifold and system are not for sale direct from Fritz Bits.
Dave from Fritz has developed them with a local company because of the lack of exhausts for converted 24v E30s. The price is £1200 including VAT, and that is for the manifold and complete exhaust system, including all mounts I believe. Im sure Dave said they have a life time warranty also.

As I said above, £1200 might seem like a lot, but once you have priced up a decent exhaust and 6 branch for an M20 engined E30, it doesnt seem so bad.

[Nic01101011]

Why is a new exhaust manifold required, does the e36 one not fit in the engine bay?

[Cook318IS]

I am still sceptical about Fritz's offering until I see it dyno'd on a reliable rolling road, (Sheps/Sal/Surrey) not Fritz's...

I sort of agree with you there. I think a few of us have found the fritzs dyno to over-read a tad. You surprise me about an s50 manifold won't be as good as an m50 specific manifold, i would of thought that it would be an upgrade? Does that mean that a stainless steel exhaust manifold based m52 manifold that tries to adhere to the physics of exhaust gasflow (obviously still modified to fit an e30) be better than an s50 manifold on in an e30?

[Jhonno]

The ports on an S50 are massively larger.. Creates a huge step right by the cylinder head, it might give better top end figures, but the mid range and bottom end will/do suffer (I have run an S50 manifold on an M50)

An M52 specific exhaust manifold would suit better yes! I think Dave's offering is ideal for M50/52's but S50's.. I am not so sure, but open to being proven wrong

[Cook318IS]

Sorry for going abit off topic guys how much would a stainless m52 manifold be in gains do you reckon - obviously if its been done correctly! I don't think anybody does m52 stainless manifolds for e30s do they?

[Jhonno]

Dave does..

[jmc330i]

Why is a new exhaust manifold required, does the e36 one not fit in the engine bay?

Slightly different to the US cars as we are RHD, so the steering linkage runs through where the manifold/downpipes want to be. Its an ok job to mod the M50/52 bits to clear everything, but a 6 branch that will help power is a logical upgrade.

I am still sceptical about Fritz's offering until I see it dyno'd on a reliable rolling road, (Sheps/Sal/Surrey) not Fritz's...

I sort of agree with you there. I think a few of us have found the fritzs dyno to over-read a tad.

Ive only had my old touring on the Fritz RR (just after it was installed), so cant/dont think I should comment on the reliability of results etc, but TBH I wouldnt take any reading as accurate other than from an engine dyno.
Any RR will be useful if you do back to back runs (before and after mods) to show any gains, no matter what that figure is - if one RR gives shows one car at 200bhp, then 210bhp after a chip and exhaust, and then another RR shows the same car at 210bhp before and 220bhp after the same mods then the gains are still the same, just with a slightly different bhp figure.

You surprise me about an s50 manifold won't be as good as an m50 specific manifold, i would of thought that it would be an upgrade? Does that mean that a stainless steel exhaust manifold based m52 manifold that tries to adhere to the physics of exhaust gasflow (obviously still modified to fit an e30) be better than an s50 manifold on in an e30?

As Dan said, the ports are a fair amount bigger on the S50 compared to the M50/52, so I do agree with him in that I dont see how an S50 designed manifold will give good gains on the M50/52 - however, I cant ignore my arse-dyno and Daves M50'd car (which in his own words has been ragged to ****) went very well.

[Jhonno]

I think it was an M50 designed manifold though.. So I would expect that..

You make a valid point about dyno's only being useful really for before and after.. HOWEVER, Fritz's dyno is known to show consistently higher figures than it should do, hence why I would like to see it on a dyno that is known to give more expected figures.. And have no connection with the venture

[DanThe]

I don't think anybody does m52 stainless manifolds for e30s do they?

Not yet, but very soon

[jmc330i]

I think it was an M50 designed manifold though..

The Fritz manifolds were M50 designed AFAIK. The one Dave has done (not Fritz) was done with his S50'd E30 in mind.

You make a valid point about dyno's only being useful really for before and after.. HOWEVER, Fritz's dyno is known to show consistently higher figures than it should do, hence why I would like to see it on a dyno that is known to give more expected figures.. And have no connection with the venture

As above, Daves system are not connected with Fritz - he just happens to work there. Im not even sure if he dyno'd his systems on the Fritz RR.
But yeah, I would offer my car for it to be dyno'd on someone elses RR

If Fritz's dyno does give higher figures than others, that 'over reading' (for want of a better term) will be consistent on a back to back run.
If I took mine there and got a figure of 300bhp, but it only showed 290bhp on another RR, that wouldnt bother me as long as any mods that were carried out gave the same gains on either RR.