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

[chu346]

318i 1989 M40 engine
T3 turbo hotside a/r .48 internal wastegate
30lb injectors
large volvo intercooler
Megasquirt V3 extra
Innovate LC-1
Running 6.5 psi






New Turbo

[GrindCulture]

Is this one of the A-Tech 318 iT's?

[chu346]

No, done it myself.

You can probably tell from the poor finish, lol!

[GrindCulture]

Doesn't look too bad, what kinda figures is it pushing out?

[chu346]

Dunno, only started mapping it yesterday.

The wastegate is set to 6.5psi, so i think it must be 150+

[baptie0]

what manifold are you using?

looking good btw

[richard-the-nutter]

nice installation, should be allot of fun

[chu346]

I designed the log manifold using weldable el's and had a local firm weld it for me.

[appletree]

Looks like a nice install! great work

[fowler]

good effort should easily take 10psi all day when mapped properly may be more

[bmwowner]

what did it cost you to build?

[chu346]

So far i'd say it has cost me £1100 parts and labour, doing as much work myself as possible.

Positive pressure starts at 1800rpms and full boost by 3000. It honestly feels faster than my old 2.7 which had 193 bhp. This car just wants to go to the redline, and then when you change gear it drops down to 3700rpms and is at full boost again, it's like the power don't stop. Never felt that in an N/A car before, not like this anyway..

Anyone who wants to upgrade from a 1.8 to 2.7 should go turbo instead. I spent £2k+ on my 2.7 stroker that i built myself and it still wasn't finished. Yes it felt great but it didn't give the rush of this, and 11mpg wasn't good

BTW the 2.7 was in a cab so this car is a lot lighter.

[fowler]

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

[chu346]

3.91 diff to make the most of this conversion

Already fitted

Might go 3.73

[fowler]

na 3.91 is the best ratio IMHO others too long big hole in boost between 2nd &3rd

[Gunni]

We just came off a little mapping session.

This is such a simple nice little machine.
little boost creep but thats just better

I think this at 12psi would be REAL nice as a daily, comes in nice and early.

I´m reading about 165-170hp@65% duty on these injectors.

[Ant]

Nice to see this dream realised

I really like a snailed M40, something sooo wrong but soo right.

whats the arse dyno reading gents ? should be approx 160 HP on that boost setting, monster TQ sub 2K too I bet ?

Quality !

[Gunni]

It´s boostin from 2k onwards, I´ve been in some 400hp monster last month so monster torque doesn´t apply for M40´s

But when run through the gears it was clearly peppy and accelarated nicely.

30lbs@65% is ~ 165hp or so if BSFC is .5

At 12psi I´m pretty sure this little thing would behave like a REALLY nice 335i E30.

[rix313]

Done a flippin good job for £1100!

[XRMike]

Hey matey what injectors are you using? Im starting on mine and need some injectors. Thanks Mike

[appletree]

Any build pics, would be intrested to see some.

[cypriot_boy_2k7]

could you get the same manifold made up again? i have a t28 with an adjustable wastegate anygood? did u need and internal work done?

[chu346]

Saturday night I saw Gunni, within 45 minutes he'd sorted out my map and totally smooved it out and got everything running sweet. He's a wizard. Thanks Gunni

Did a quick 0-60 on the g-tech lastnight which came out at 7.8 seconds, I think I need more boost

I've still got plenty to do though, I need a washer bottle for starters as i'm struggling without one. I'm using the standard center and rear exhaust so that needs changing. I'm gonna put in non stretchbolts and add boost control too, 10psi sounds good

I'm using volvo injectors possibly 0280150804

A guy i knew made the manifold for me, to make another it would cost £200 and tbh I would redesign it. I've had to bash the wing to make room so the turbo has room to move. Also I have to bolt the turbo to the manifold before fitting them both to the engine. You'd be better off making your own.

As for the turbo, I don't know, soz!

Appletree what kind build pics are you after??? I'm not one for taking pics whilst i'm getting my hands dirty, I just get on with it, plus I don't want to dirty my camera. I might be able to take afew pics for you now if you want, but i'm not going to take that manifold off, lol.

[appletree]

Just genraly intrested realy different people think and do things differently so its good to get ideas. Where did you get the oil feed from?

[chu346]

The front of the oil filter housing, near the water pump. Ant told me that one years ago. The only problem is that I ordered the oil feed a meter too long and have to route it round the back of the engine.

[GeoffBob]

Great build Chu! Fantastic work you've done there. Light weight turbo'd engine - way to go.

What compression ratio are you running (modified, or did you keep it stock)?

Watch out for detonation if you go in search of higher boost! Retarding the timing to kill the detonation is just a bandaid that will stop the detonation, but actually cost you power. It's a well proven fact that running lower boost (before detonation kicks in) but at optimum spark advance will give you better performance than higher boost with retarded timing. What you are looking for is highest boost possible at optimum timing advance, and not beyond. The only way to find optimum timing advance (indicated by optimum wheel torque without detonation at each given point on your ignition map) is unfortunately on a dynamometer.

I look forward to seeing more of your car here.

[Gunni]

That is a mis understood conception.
That low boost and high advance is better then high boost and low advance.

The optimum advance changes as the boost changes. On 90% of all boosted cars the optimum timing can not be reached at elevated boost leveles without higher octance fuel. So closest to optimum timing would be as close to knock as possible. And that is easily findable on the street.

So the goal is to design the system for the power level and not boost level.
Boost figures are just by products of cramming more air into the same space.

People always get hung up on raising the advance and raising the advance,
I can tell you that you could boost a 325i to 400hp with safe timing for long term drivability.
Now isn´t that better then running slightly less boost and higher advance that if something only slightly changes(minor boost leak that causes turbine overspeeding and charge heating) and knock starts to settle in?

[GeoffBob]

The optimum advance changes as the boost changes.

I never said it didn't! I think this goes without saying due to the change in density of the inducted air with boost, and thus the commensurate change in burn time of the air/fuel mix which is density dependent.

So closest to optimum timing would be as close to knock as possible.

So the goal is to design the system for the power level and not boost level.

Gunni, are you agreeing or disagreeing, with me? Make up your mind. I never said don't run the highest boost possible, I said don't run with detonation. And if you have to significantly retard the timing in order to run the higher boost, then all you'll achieve is higher boost, not more power.

People always get hung up on raising the advance and raising the advance

I never said anything about increasing the advance. What I said was, find the optimum for the given level of boost that doesn't result in detonation! However, I stand by the fact that the only way to tell whether an increase in advance at a lower level of boost will result in an increase in wheel torque is on a dyno. And for the record, I don't own a dyno and I'm not trying to sell dyno time to anyone.

There's no misconception with regard to this, by the way. This is a well proven fact that you'll find documented in all the big turbo tuner guides (Try Graham Bell's book for starters). If you think you can show otherwise, I suggest you rewrite the text books and make a fortune.

[Elecblondie]

Woah there. Chill out.

[Gunni]

I never said anything about increasing the advance. What I said was, find the optimum for the given level of boost that doesn't result in detonation! However, I stand by the fact that the only way to tell whether an increase in advance at a lower level of boost will result in an increase in wheel torque is on a dyno. And for the record, I don't own a dyno and I'm not trying to sell dyno time to anyone.

Finding the optimum advance,
you make that sounds like most engines are capable of reaching that advance. Well they are almost ALL not, they are detonation limited when under boost as in most cases the design is lacking and the fuel is incorrect , thus peak power will be closest to detonation.

Of course lower boost and optimum timing is BEST.
But do you want to run on the limit of best and be at the point nearest to detonation(even with a non detonation limited engine) or just run a little more boost and keep the advance down. Most people lack the ability to tune for scenarios where there are changes that occur,

such as the need to retard timing as air temps go up. This mean that a good solid 3rd gear run is mapped fine, but a long 5th gear run get´s higher temps and detonation.

[GeoffBob]

Of course lower boost and optimum timing is BEST.

Thank you kindly sir, that's all I was trying to say. The rest I think we are in agreement upon, bar one minor point, and that is the meaning of the word "optimum".

By my understanding "optimum" refers to, in simpler terms, the best you can get for your current situation/parameters. Thus, "optimum timing" is that measure of timing angle that gives you the best results possible under the circumstances. IE, no detonation, best torque etc. for a given value of RPM and load. The "optimum" is however not the "ideal".

The "ideal timing angle" is that which results in the height of combustion (giving the piston maximum push) occuring slightly after TDC. Since the time from spark to the height of combustion is a function of the charge density, this time varies with AFR and Boost pressure, and thus the necessity to map the timing angle.

Unfortunately, and I think we are in agreement on this, under some circumstances the ideal timing angle cannot be achieved and must be retarded (or octane/knock resitance increased) in the event of detonation.

Finding the optimum advance, you make that sounds like most engines are capable of reaching that advance. Well they are almost ALL not

Thus optimum timing can always be achieved. Ideal timing, however, cannot.

It appears that you are using the term "optimum timing" to describe what I know as "ideal timing". I think this is why some confusion has arisen between us.

Most people lack the ability to tune for scenarios where there are changes that occur, such as the need to retard timing as air temps go up. This mean that a good solid 3rd gear run is mapped fine, but a long 5th gear run get´s higher temps and detonation.

I am in 100% agreement with you.

[Gunni]

This optimum timing I´m talking about it known as

Minimum Best Timing, or MBT for short. Sometimes called Minimum Best Torque.

what it is is that it´s the least amount of advance to reach the best possible torque.
This advance + 3 degree may give same power so there is absolutely no reason to go higher then MBT.

The peak pressure your talking about occurs at about 15 ATDC till about 25DEG depending on engine configuration (crank angles and rod ratios.)

[GeoffBob]

Dude, you just won't let go will you.

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 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 can't fire the plug at MBT then its called optimising the best of a bad situation in order to find optimum timing.

Now, I handed you a nice friendly way out in my last post, next time I'm gonna throw the whole fuggin thermophysics text book at you.

I'm leaving now to chill out.

[Gunni]

Your new to the internet?
Things aren´t always written in the context you read them in.

I´m not "not letting go"
I was just explaining my stand on "optimum" timing.

If you think you can teach me anything about thermophysics then I´m all for the read.

[GeoffBob]

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.