318i M40 turbo 190bhp@8psi *Breaking*

[GrindCulture]

This is like Jerry Springer vs. a Thermophysics lecture

[Gunni]

Yeh, you're right, must be my fault for taking a pretty basic and factual sentence out of context. Come on, this isn't art appreciation here?? There's nothing subjective about either of our posts.

So for those in the back row who are hard of hearing I'll repeat myself more clearly:

If you meant MBT, then why didn't you just say so when you had the chance? That's not what optimum timing is, and that's a fact.

Another hard fact is, to achieve peak pressure after TDC you have to fire the plug at MBT because of the time it takes for the air-fuel mixture to combust (which is a function of temperature, pressure, charge density etc).

If you haven't grasped these two facts then clearly you need to review your fundamentals.

There is nothing I´m missing,
I just thing we have different "naming conventions" for the same thing.

I only see things like so.

Optimum timing is MBT ( to me ) any other ignition advance is not "the" optimum. But I will agree that there is an advance you use when you do not reach MBT and I guess you could call that optimum, I would just call the whole engine setup weak

[GeoffBob]

Fair call. I can agree to that.

But I will agree that there is an advance you use when you do not reach MBT and I guess you could call that optimum.

No, no, no. Not in advance of MBT, but retarded behind it. I can see no reason to tune in advance of MBT, heaven forbid!

Agreed, MBT is best, but if detonation occurs (for whatever reason) the best timing angle you can hope to achieve (the one that I call "optimum") is retarded behind MBT, not in advance of it. I would never tune in advance, that would be disastrous.

Going back to the very first point that I made:
Retarding the timing (behind MBT) to avoid detonation for sake of tolerating higher boost is not practical since it has been shown clearly and irrefutably in many dyno tests that lowering the boost and advancing the timing back towards MBT will actually produce greater wheel torque than having higher boost with retarded timing. Of course MBT is a function of boost pressure due to the fact that the combustion speed is a function of blah blah (as above).

Finding that value of boost and timing angle that delivers maximum wheel torque (at a specific RPM value on the map) is what you should be aiming for (assuming you are tuning for performance, not economy or emissions). Not simply retarding the timing at any given manifold pressure to avoid detonation.

[Gunni]

Your not getting me again.

I said "an advance" meaning advance from TDC of any kind, not advance of MBT ;)

[e30_singh]

Nice turbo setup, sweet for a 318i what makes it better is it costs £1100

[GeoffBob]

I said "an advance" meaning advance from TDC of any kind, not advance of MBT ;)

Then say what you mean and mean what you say. Stop hiding behind semantics.

"Advance" and "Retard" are not absolute terms. They are relative terms, like forwards or backwards, or, up or down. Advance and Retard are not defined relative to TDC unless you state this explicitly. Next time, state it if that's what you mean.

[ShakeyC]

One for the zone gold

[GeoffBob]

Gunni (Ingimar?),

I think I owe you a huge apology. I've been browsing this forum and something just struck me while I was looking at some of your photos - You're Finnish.

The whole time I thought you were winding me up, and it turns out its a simple case of a language barrier. That's why I was struggling to understand you, and probably why we are unaccustomed to each others terminology. With my limited language skills I wouldn't have a hope in hell of posting anything sensible on a Finnish forum, so I admire you for posting here (and for putting up with my crap).

Please accept my sincerest apologies, This has been an embarrassing lesson for me. Next time we debate the intricacies of turbocharged engines I shall be more sensitive to the fact that we studied in different languages.

Regards
Geoff

[nickso]

One for the zone gold

if only we knew what they were on about

[Gunni]

Gunni (Ingimar?),

I think I owe you a huge apology. I've been browsing this forum and something just struck me while I was looking at some of your photos - You're Finnish.

The whole time I thought you were winding me up, and it turns out its a simple case of a language barrier. That's why I was struggling to understand you, and probably why we are unaccustomed to each others terminology. With my limited language skills I wouldn't have a hope in hell of posting anything sensible on a Finnish forum, so I admire you for posting here (and for putting up with my crap).

Please accept my sincerest apologies, This has been an embarrassing lesson for me. Next time we debate the intricacies of turbocharged engines I shall be more sensitive to the fact that we studied in different languages.

Regards
Geoff

I like you Geoff.

Cause you know your stuff, and I can see that we where in fact on the same page just reading different sides of it

I´m not Finnish but Icelandic.
And my terminology is rather --- well , here and there to say, as I am mostly self tought and have only been able to converge with people from non english speaking countries so terminology takes a back seat to understanding concepts when people from many different countries are writting in english using words translated loosely from their own language.

But I am living in the UK and am picking up on terminology used in the motorsport sector here. So in a couple of years I should be well accustomed to local terminology.

And yes I should have answered you more completely so not to cause a mis understanding.

[GeoffBob]

Thank you for your understanding Gunni. I'm afraid my education was quite, well, German, in its precision. Where words used in an Engineering context have a very fixed and precise definition. I work in an environment where this is still so. I am sorry for this.

I can see that we are going to have a lot to discuss in the future. I am particularly interested in experimenting with different fuels, mostly with varying amounts of methanol and toluol (methyl-benzene) added. But maybe this is a discussion for another thread? By now I think I have posted enough over Chu's work. Sorry Chu, and once again, great build.

if only we knew what they were on about

You are so right Nick. You must think I'm a complete nutter by now.

[chu346]

I'm going wastespark, boost control parts are ordered just looking for for some non-stretch bolts now before 10+psi

Let me know what pics you guys want and i'll try and take some this weekend.

[fowler]

Chu you can run 10 psi on bog stock engine fella i did !!!!!
i ran 0.8 bar on mine without any problems
What coil pack you going to use ????
a citroen one is good as you will struggle for places to put the coil pack unless you have reloacted the battery to the boot



Hope that helps bit messy the photo's but they were taken when car was in process of being finalised

[Ant]

I made a bracket for the coilpack on chris P's M40T, sits where the stock dizzy cap normally resides

Nice,

[Jhonno]

if only we knew what they were on about

You are so right Nick. You must think I'm a complete nutter by now.

Was a good read for those who could follow it though


Looking good chu

[chu346]

I made a bracket for the coilpack on chris P's M40T, sits where the stock dizzy cap normally resides

Nice,

That was always the intension. I've had to put the standard coil where the battery tray is for now, so the battery is in the boot. I wanna put the battery under the bonnet again and put the washer bottle in the boot.

I've got a cavalier redtop coilpack which was donated by a friend

I want the non stretch bolts because i'd like to run more than 10psi really, even if I don't i'd like the extra security.

[GeoffBob]

Bolts or studs Chu? Any idea if ARP make a set of studs for your engine? I'm guessing that they would have something in their collection that would fit. I don't think you can go wrong with a set of ARP studs and a Cometic all metal gasket? I'm running 22psi boost on a Toyota 2-litre 3SGTE motor with this setup (on pump fuel, no detonation) and she's held together so far.

I'd still like to know what your compression ratio is please?

[rix313]

What are ARP bolts

[chu346]

I best tell you before you start another arguement, lol.

It's 8.8 i think. I wanna keep this a cheap build, i can't afford ARP stuff. I was thinking more like metric blues. Would any 12.9 M10 bolts of correct length do?

[appletree]

What are ARP bolts

they make non strech head bolts aswell as loads of other hi grade stuff
http://www.arp-bolts.com/

if i remember correctly ARP dont do bolts for the m40/2 engine, they may be able to match somthing if you email them with thread types and measurements

[Gunni]

They do , VAC motosport sells them at least.

[GeoffBob]

I best tell you before you start another arguement, lol.

Yeh, sorry about that.

It's 8.8 i think. I wanna keep this a cheap build, i can't afford ARP stuff. I was thinking more like metric blues. Would any 12.9 M10 bolts of correct length do?

A set of ARP head studs aren't too expensive, not compared to the price of having to pull the head off after losing compression. Also, there is something to be said for using studs in place of bolts due to the way in which they tighten up. I won't bore you with the details.

12.9's are just a higher strength high tensile bolt. Basically, they are induction hardened (with some chemical treatment I think) to the point where they are so tough that they don't stretch. The disadvantage of these type of bolts is that when they reach their elastic limit they almost immediately shear because (as a result of the hardening process) their UTS (ultimate tensile stength) is so close to their elastic limit!! Stretch bolts will stretch a little before they shear. Sadly they also stretch a little during everyday usage. The disadvantage of this is the necessity to retorque periodically (usually only once or twice more after a re-build). I'm not convinced with regard to the use of non-stretch bolts on a turbo'd or high-compression engine, but then I have to say that I steered clear of them and thus have no practical experience using them on anything else other than normally aspirated low to medium compression engines.

[fowler]

That was always the intension. I've had to put the standard coil where the battery tray is for now, so the battery is in the boot. I wanna put the battery under the bonnet again and put the washer bottle in the boot.

Chu just geta 325 washer bottle and cut the small intes was bit off job done and put it in the original place
as Ant did for me
is perfectly ok and even on a cold day you have pre heated washer fluid

[chu346]

It won't fit, my turbo is further forward than yours.

[fowler]

fair enough mate would keep battery in the boot then and move the washer bottle to the battery tray

[stonesie]

A 324d washer bottle fits in the battery tray area I think

[smith4130]

its defo a worth while conversion i had mine for nearly a year and i loved every minute of owership.
gives 2.7 stroker a good run for its money but you need a 3.91 diff to make the most of this conversion

there's a 3.91 in it now ben......

[CHRISP]

I made a bracket for the coilpack on chris P's M40T, sits where the stock dizzy cap normally resides

Nice,

URL=http://imageshack.us][/URL]

Looks like was made to go there.

[chu346]

Thats what i was planning on doing. Modded the megasquirt board today for wasted spark, boost control and ICV control but it's dead now and the car won't start, won't even connect to megatune

[CHRISP]

I have a alot of problems with megasquirt and cold start . Ant is going to do some rework on my car and sort out my cold start. it mite be worth talking to him.
Good luck in your m40 turbo conversion mine makes me smile all the time!

[scottidog]

I would like to see a pic of the exhaust manifold and how i has been made, im seriously considering this.

[fowler]

all three m40 turbo's have different style of manifolds as two were top mounted and one bottom mounted
they wereall one offs .
so either speak to Chu for his drawing or photo's as the other wre made by A-Tech

[chu346]

Neither are mine

http://www.e30zone.net/modules.php?name ... o&start=25

http://www.e30zone.net/modules.php?name ... o&start=25

Might be selling my manifold soon cause I wanna make a new one.

[chu346]

Boost control now added, but turning up the boost means the spark is now being blown out when I get to 8psi. So I have purchased some new sparkplugs that are a grade colder and gapped them to 0.55mm from 0.65mm. The original plugs were 0.75mm. After fitting the new plugs my whole map went lean, does this mean i'm burning more fuel and the engine is running better or does it mean that all the fuel isn't being burnt so easily and more fuel is needed and some is being unburnt?

I'm going to try to get it running wasted spark later, will I be able to open up the plug gaps? If so by how much?

[cypriot_boy_2k7]

how much for the manifold?