1914 turbo bug

[richie,uk]

Having just read through all off your thread I have to admire your persistence,it would have put many off with all the issues you have had.
Heres my input

1st what fuel octane and brand are you using?
2nd how are you checking/confirming your timing? I only have the older e48 dta but there is a setting in there to adjust the crank trigger with a + or - figure,even setting the crank trigger angle does not make the actually timing correct,I have to fine tune it and have seen up to 8degrees out on mine before adjusting
3rd what size injectors do you have?
4th have you checked that your fuel system can keep up? seeing fuel pressure going up is great but will it hold pressure under boost/load?
5th you need to open up & match port those intake manifolds,boost is only a measurement of restriction,if your intake is too restricted then you will see a higher boost figure than the actual chamber see's
6th does it ping most when you get onto the throttle? have you done anything to set the accellerator pump effect?

The renault fuel pump,dead end injector rail and that bmw pressure regulator scared me,thankfully they are all gone now

I am sure you can find the problems and make that the fun real quick street car it should be

cheers Richie

[bazibbo]

Hi Richie, (love your cab)

I generally run Shell Optimax or rarely any available get me home higher octane... but usually optimax.

(EDIT Optimax surely I must mean shell V-Power )

Timing wise, I have to rely on my rolling road to check timing as I haven't got the necessary powered light, which worries me. They did check it. I've got the sensor position set at 51 deg btdc which I believe is Speedshops base setting... but I'll revisit this seriously on thursday when I'm back on the rollers... and check TDC is TDC too.

Injectors are 390 cc.

I think I'm OK now with fuel pressure under load. I ran a gauge to where I could see it and appeard to hold a good 55psi @ 10psi. I'll revisit that too.

I quite fancy moving away from the mexican setup in the future, maybe to CB performance hi flow end manifolds.... just got to prove this one first

I'll get them to take a good look at the throttle transients. I've basically left them on the default settings.

Appreciate the input. I will have to start putting a bit happier spin on my thread as it does make for depressive reading! I'm still reasonably happy with things, I guess having something to mess with is a form of therapy and I'd still argue that the journey is the biggest part of a development. Still I wouldn't mind things progressing a bit faster.


So Thursday I'm back to the rolling road and I hope will take me another step forward, I'll try and get a few dyno charts out of them. The cars running reasonably at the moment. I've got most of the detonation removed, (though by heavy retardation) and whilst not fast, it has its moments. I'm guessing around 125 -130 RWHP, based on seeing 120 last time it was on the rollers, though I think I should be seeing 20 or 30 more.

Still a few self caused issues.

I'm having oil leaks from my crank pully sand seal again ... even after all my 'engine breathing' work. So double checked my breathers to find them jammed with creamy sludge. Fair enough... short journeys over Christmas maybe... but then I noticed the smell of petrol. I guess running 11.0 AFR at low levels of boost to get around detonation is the same as pouring fuel into the oil filler. - I'm not there now before you ask... and oil change tomorrow.

Cleaned everything out... ran a 3/4" pipe (water hose) from oil filler to my air filter and had an hours drip free driving! then (as the sun came out) I had a 20 mile cross country thrash - managed to overheat and kink the pipe - oil everywhere, thought I'd set fire to the thing!

Never mind - roll on thursday.

[richie,uk]

Optimax is good enough for 18psi boost so thats plenty

Holding 55psi fuel pressure with pressumably 10psi is not that same as having enough fuel under load when the injectors are wide open,you need to be able to watch a pressure guage with sustained load,while they are doing a pull on the dyno is a good way to be sure,or use a video camera to record the guage while you are driving

Good luck on thursday,look forward to seeing how you get on 11.8-12.0afr wide open on boost is fine,maybe a little rich but it should live longer that way than lean.

To rich can show as lean on afr guages as there is not as much oxygen present which confuses the sensor

I enjoy the building and trials of a project as well so know what you mean

cheers Richie

[bazibbo]

Been on the rollers again.

Well things are looking quite a bit better than they did at the last rolling road session last year. I'd like to think that the work I did on the fuel supply have gone some way to sorting the issue. Most, though not all things got checked due to time constraints, but ignition and fuel pressure were spot on.

There's a little more work to do on the mapping, we didn't get up past 4000k and I think there's a few light throttle glitches to sort, but things are looking up.






The fuel compensations aren't a million miles off, or at least a big improvement over the previous ones which were blatently out..



The retard shows a big improvement too... I've not shown you the ignition advance map (!) but we're certainly not retarding it by up to 50% as before.

I need a bit more work on it, then I'll probably lift the boost to 1 bar and try to get to my 150 at the wheels target. No power run as things weren't finalised, but I should have one at the next session.

Oh and intake temperatures never rose above 28 degrees... so I'm pretty happy with my little chargecooler.

[Clonebug]

Very Nice!!!

[yvre]

So, why was it pinging???

[bazibbo]

You know... I still don't really know and although we're nearly there, there's still a few bits of detonation to tune out.

I'm happier, but there's still the issue of the fuel compensations NOT acting as physics say they should, and I've still got a few people on the DTA ECU forum saying things are wrong, possibly with the way the mapping is being done. I'm looking into that one.

getting there..... honest

[andy198712]

great IAT!

[richie,uk]

So at 5psi and 3000rpm you nearly added 100% fuel? from - 25 to + 70?no wonder it was pinging!!!

I am certainly not a mapping expert but it looks to me like you are only mapping the pressure compensation and not the actual fuel map itself? I cant see this ever being 100% correct doing it that way,the fuel map should be done 1st,then just tweaking of the compensation map if needed,DTA gives a compensation map to put it which is linear,at least they did when I did mine
EG 5 psi boost is +50% fuel
10 psi boost is +100% fuel
etc etc

The pressure compensation for the ignition map works the same way,you should have a fairly conventional ignition map,then the pressure comp will add or subtract timing depending on the vacuum or boost level.
Is that close to how you are doing it?

cheers Richie

[bazibbo]

It feels to me, Richie, that they creating the 2 base maps, ignition and fuel and then dir the two compensation maps rather than setting the compensation maps first, but yes, they're doing half the job on what should be 'set in stone' compensation maps.

I can ( or they can) loose the 20 x 16 compensation maps and just use the simple 2 column version. Probably need broad brush strokes until I know it's gonna work.

It does run better than before... though I've no comparison. Don't think we're over 125@ the wheels yet, feels ok but I'm told it should be '150 on ANY dyno' (Daz Chandler)

So, man up Barrie and tell the dyno operator that something may be up

[Wally]

So at 5psi and 3000rpm you nearly added 100% fuel? from - 25 to + 70?no wonder it was pinging!!!

I am certainly not a mapping expert but it looks to me like you are only mapping the pressure compensation and not the actual fuel map itself? I cant see this ever being 100% correct doing it that way,the fuel map should be done 1st,then just tweaking of the compensation map if needed,DTA gives a compensation map to put it which is linear,at least they did when I did mine
EG 5 psi boost is +50% fuel
10 psi boost is +100% fuel
etc etc

The pressure compensation for the ignition map works the same way,you should have a fairly conventional ignition map,then the pressure comp will add or subtract timing depending on the vacuum or boost level.

cheers Richie

^^ that!
It really is that simple.

[bazibbo]

You lot will be sick of me soon! Honestly, I feel like a broken record... If we ever meet, I'll probably get a slap.

I've managed the basics before, setting the boost compensations is easy... It's when I know im out of my depth and have to go elsewhere to get the basic maps sorted.

It has been suggested that I find another rolling road...

[Wally]

No worries mate, I think we all needed our time to figure it all out the first time.
Keep at it, the rewards are truely worth it and you'll laugh at your projected 150 whp when your at 250 whp on the exact same engine.

[richie,uk]

You lot will be sick of me soon! Honestly, I feel like a broken record... If we ever meet, I'll probably get a slap.

I've managed the basics before, setting the boost compensations is easy... It's when I know im out of my depth and have to go elsewhere to get the basic maps sorted.

It has been suggested that I find another rolling road...

So is the dyno operator tuning it for you? or are you doing it yourself? The mapping of the regular fuel and ignition shouldnt be to difficult if you know what afr you are aiming for,but it is time consuming for sure,but a good dyno operator who knows DTA should be able to map it pretty quick through experience alone.

cheers Richie

[bazibbo]

The dyno operator is doing it for me... I'm a little out of my depth, but frustratingly know enough to see thats somethings amis.

I'm beginning to think (hope) its a simple case of them not knowing the DTA ecu and NOT setting the manifold compensation maps first.