DTA ignition MAP

[samg60 0]

Just wanting to have a play around with the ignition map on my car at low rpm to catch idle a little better, just looking at the map, what are the number that run across the top, I understand the side is rpm and the numbers in the box are degrees but wht are the top, sorry really new to engine mapping and just want a few points.

 

also engine can flood really easily when staring meaning I have to run a spark test to clear, anything i should change on the fuel map ?

[CrazyDave 0]

Hi Samg60,

 

usually you would have rpm on one axis and throttle position or MAP on the other. But from you screen shot yours is not that clear, it does say throttle on the right but I would expect it to be in degrees or %. Yours looks like kPa /10 across the top? Although that means your only running 0.5bar of boost?

 

I'm just working through this stuff myself with a MegaSquirt and that can have either of the above.

 

A few guys on here are running DTA's so some help should be along soon.

 

Your cold start problem will be over enrichment during cold cranking, should be a setting for this under cranking / cold start somewhere.

 

Does it start and then stall? This could be after start warmup settings.

 

You've got some very low numbers near your idle sites on the left, the 1.0's and 3's these may be giving you a problem. Usually the edges would have quite high numbers as this will increase the engine speed when in that region and prop up the idle.

 

Looks like a nice piece of kit you've got, bringing it to the Stealth day?

[samg60 0]

Thanks matey, when is the stealth day, definatley running more than .5 bar boost hits about 1.3 - 1.4 bar so maybe it is throttle, I do think its over enrichment at cold cranking just not sure what number to chuck in, I may post up some more screen shots later if anyone one to take a look and throw some ideas my way, original map is by stealth and is a belter it just seems to need a bit of work at cold start and idle.

[CrazyDave 0]

I would have thought so with 297hp!!!!

 

The cold start is the bit that needs the most work, and deep cold start is the most difficult because you have to wait for cold days and then you only get one or two goes at it before having to wait for another day.

 

I know you have DTA but have a look at the megasquirt website, just do a search in google for the megamanual. It's got loads of info on setting up for all kinds of conditions, ignition and fuel etc.

 

Post the screens up, I'll have a look and help if I can. If your anywhere near Worcester your welcome to pop in, I'd love to see the conversion on your car.

[CoxyLaad 0]

the number across the top are engine load sites ie throttle position

[Chris VR6nos 0]

Which are u using, the P8pro?

 

 

Chris

[samg60 0]

just an e48 at the moment but looking the possibility of s60 or p8 pro in the future when a bigger blower and aquamist find there way onto the car.

[Kevin Bacon 5]

S60 will be perfect for your car and they're currently working on Knock sensing. The P8 won't get that for ages, but a lot of P8 uses prefer to use EGT instead. But i prefer knock regulation personally.

[CrazyDave 0]

Wow, the start fueling looks way over the top. As I already said I'm no DTA expert but 178% extra fueling is a bit much. Surely I'm not reading that right?

[samg60 0]

yeah not too sure about that either, I am going to adjust these and see how it behaves as its definately the reason its flooding at start sometimes, I have taken 30 off and will see how it behaves, with regard to the start fuel map when does it stop using this and is it simply the amount extra of fuel that it throws in on top

[CrazyDave 0]

I've just downloaded the manual from the DTA website and had a read up of starting enrichments. Have a look here http://www.dtafast.co.uk/Downloads/Downloads_Index.htm

 

It's the S8 manual.pdf

 

The table is laid out engine temp across the top, and engine cycles down the left. So when you cold start the fuel % in the table is added to the main fuel map for the number of engine cycles down the left and for how cold the engine coolant is. The table they recommend for most engines does not have numbers bigger than 100% dropping to 60% after 10 engine cycles.

 

Your map needs more numbers and they need to be a lot lower IMO. It's not showing any enrichment above 50degC and way to much in the first 10 cycles. If you try and it doesn't work you can always go back?

 

As for the enrichment finishing this is what the DTA manual says: The fuel is added until either the number of turns specified is exhausted or a 0 is found in the map.

[samg60 0]

Hi Dave yeah set the first row to 100 and it still starts fine so am going to try that for a while, will read through the manual and have a play.

have adjusted the ignition map as well by a few degrees around the 800 rpm - 1000rpm as the engine isnt under load at these revs so figure I can play around a little more.

kinda fun this :-)

[CrazyDave 0]

Yeh... messing with the tuning is great fun, as long as you don't break it.

 

Are you going to Stealth RR this Sunday? I'll be having a look around and my cars on the rollers! Fully standard though, even the Megasquirt isn't on fully yet, need more time and less work!

 

I could run VAG-COM on my Golf 1.8T and get some standard ignition logs for you? OEM settings are always a good place to start.

 

I did a load of logging on the VR before fitting the MS to give me a good idea of basic running parameters. The Motronic stuffs a load of advance (24deg) in at about 1000rpm and then backs of pretty quickly. Makes it a bit funny in traffic actually but I guess it give it an extra shove when pulling away.

 

The DTA has a really good idle control system (just been reading the manual again). Full PID control NICE! Can you post your idle setting page?

[samg60 0]

right then here is my idle control setting but as you can see the idle control is turned off, I am a little hesitant at turning things on and off as the MAP is from stealth and I assume things were set up when he ran the map on the rollers, but having said that I am guessing that most of the mapping session was spent tuning the car to get teh most out of it rather then fine tuning things like idle, hence the start fuel map and the idle setting being a little off.

 

so what do you think should I turn it on ?

 

afraid i'm not at Stealth this weekend was only there two months ago for the current Map (had to leave the car there as the coil packs were wired incorrectly hence my lack of knowledge about what happended on the rollers)

and it cost a fair amount of fuel to get there an back and as I havent added anything I guess my results will be very similiar (or prehaps a little higher as the weather is colder and it was mapped on 97ron not 99 as I am running)

 

will defo bring it down next year when I have done some more work on the motor.

 

By the way just started the car from cold with the new start fuel map and it started on the button after reducing the first row from 176 to 100 so may go a little lower.

 

Cheers Sam

[CrazyDave 0]

Hi Sam,

great news then, just remember that fueling only lasts for 10 cycles of the engine to get it going, but at 176% plus the normal fuel map the injectors must have been fully open, hence the flooding when cold.

 

As for the idle, you've got a 20vt engine it should have a stepper motor on the throttle butterfly, is it connected up? You might have an ISV instead to allow some air past the throttle and increase the idle speed.

 

Either way if the bypass valve isn't connected up you are relying on the butterfly being adjusted off the stop position for idle speed control. This means that all the things that modern ECU's use to help cold running, stall prevention, heavy electrical loads like cooling fans etc etc can't be used. So getting the idle better may need a valve fitting or the existing one wiring up.

 

When you have this valve the ECU will start to get hold of the throttle as the engine speed approaches idle. The PID control that the DTA does will then increase the idle air or decrease it to keep the idle stable even when the fans start etc etc. It should work really well and never ever stall if setup correctly.

 

It does take some setting up thought, I spent a good 2 hours get the VR to idle just how I wanted it. But it is really good.

 

I found out something interesting today, my car has been a bit lumpy on idle lately and VAG-COM should an intermittant crank sensor fault. When I put a timing light on, the idle timing was moving about quite a lot. I connected up the Megasquirt and the idle timing was spot on. Looks like the MS is better with the VW crank sensor than Motronic is!

 

I always fancied a 20vt C. The Golf we have has really good mid range and is so lazy to drive.

 

Dave

[samg60 0]

Thanks Dave, yeah the cold starting really deos seem to be sorted now I have also sent an email to Vince asking him to look at my map again (need to stop moidering the poor bloke :-) )

 

no stepper motor etc on my car or idle valve only a screw to stop the throttle hitting the stop i.e to allow a little air past the butterfly, this seems to work well enough.

 

car has been running brilliantly but then today I filled her up and as soon as I came out of the service station and to a junction she died, managed to keep her going by not stopping an then floored the throttle and the car runs fine again, although tootling at low revs she can occasionally feel really bogged down until i hit the throttle again and clear the fault, am wondering if the fuel pump is perhaps full of crap, going to take a look at the weekend, might order a heavy duty in tank pump from sytec as Kev suggests.

 

yeah the 20v corrado is fantastic, will happily take you for a spin should I ever catch up with ya, it is quite lazy to drive but with 300ftlb around 3000rpm it can suddenly turn into an absolute animal, need to find away to put the power down a little better. it has a nasty habit of lighting up the tires and putting you the wrong side of the road if your not careful, but feathering the throttle makes it very rapid indeed.

[CrazyDave 0]

Sounds like the low end fueling might be a bit rich. That's the only map not on here yet!

 

It's always the low end stuff that take the time really. And getting it right for all conditions is tricky.

 

Are you running a wide band O2 sensor? Closed loop control for part throttle conditions is usually the best way to get good running, especially if you have big injectors, which with that many horses I'm guessing you have!

 

I've been thinking about traction quite a lot lately. The best way (and maybe only) I can see is a limited slip diff. Unless you fancy a 4 x 4 conversion!

 

Always up for a ride in a quick C.... as long as I can play with the mapping to get a bit more!

[Kevin Bacon 5]

Just seen your post on the DTA forum about this Sam, did you get it sorted in the end?

 

Tuning these things can be a real ball ache sometimes!

[junkie 0]

Im running Haltech on mine and as with most stand alone they are not the best from cold, glad you managed to sort yours out some.

 

My problem sounds similar to yours that upon cold start cranking it will try to fire but wont on 1st crank, then will fire then stall on 2nd crank, then will fire and run, this is not everytime though, all depends on the outside ambient temp, winter is a real pain sometimes takes 5+ attempts. My plugs are not helping matters as well, waiting on the arrival of some new 1's, hopefully will help some.

[samg60 0]

Hi Matey, yeah this was all sorted, we found a resistor in line with the injectors which was screwing things up, got it out an dthen Vince Mapped it again, its been sweet since..

[_leon_ 0]

can't offer a huge amount here - but I helped a friend in his westfield map the fuel table in Mega Squirt on a live run (great fun!). the figures we ended up with to get the mixture about right were considerably lower than what we started out with.

junkie - i'm getting the exact same issue with my cold starts - every morning if the temp has dropped a bit (lets not forget i live in scotland...) - its a pita.

[Kevin Bacon 5]

That's great news Sam. Glad you found the 'pull up' resistor in the wiring. The DTA has one built in IIRC, so the two together was probably screwing up the overall injector resistance making them difficult to drive maybe? Good old Vince 8)

 

Junkie, what is your Water compensation table like? I know mine's a 6 pot, but the below settings work great for me. I've set the cold cranking fuel so that the motor spins 3 or 4 times to build up oil pressure before firing and when the engine is warm, it fires on the key instantly.

 

Also, if your lambda is kicking in too early, it will pull out all the cold fuelling, so I set my lambda to switch on at 60 deg water temp and to wait 90 seconds before engaging when hot starting.

 

The start fuel map is temp along the columns and crank revolutions in the rows.... there's 10% enrichment at 50 deg, that's what fires the motor on the key when hot 8)

[samg60 0]

Problem is Kev the loom thats being used is entirely home made so now it doesnt have a pullup resistor, but all seems good now, it took month to figure it all out but it really has been faultless for the last 6 months, apart from breaking gearboxes.

[Kevin Bacon 5]

Yeah, that's why I'm restricting my boost to 11psi!

 

What gearbox are you using?

[samg60 0]

Well at the moment its got an awful 8v passat gearbox, (awful ratios) 100 in 5th at about 5000rpm :-( however in the process of rebuilding a CCM one to go on and also have the option on a g60 rebuilt box with vr 1st and 2nd and a lower final drive, with pelquin diff bolts, so that might go on then I can spend a lot of time sorting the CCM box and maybe afford a better diff, I killed the g60 one and the passat one has now started to whine, they really dont like the torque do they !!

 

lots of plans at teh mo but not enough time and money...