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[chrisgixer]

Yes and if Webby goes that route he'll also be faced with all the steering mods and chassis mods that you've been deliberating over for months

Let's start simple for Webby's first learning project, eh?

Yes, but it could be made to work, with a steering box. The manifolds will have to be modified anyway, and they can be swapped to the opposite sides so they exit forwards, allowing turbo fitting where there is a bit more space.

...and it's almost bloody years by now I'm sure although time related, rather than being stuck.

[chrisgixer]

Although seriously, it does have to be an auto for young bear.

[cem_devecioglu]

Seems like there's sooooo much to take in to account. its actually a mine field.... and thats even if the bottom end of the v6's could hack it.

thing is it looks pretty darn straight forward on things like ''mighty car mods''. the hard bit being the wiring of the ecu and fabricating manifolds.

they shoved a turbo on an mx5. there was no mention of ''we've calculated we can do this'' so wonder if that'll start knocking quite quickly 

lets say a field full of money pits that drain you when you fall into  


I can say , you will reach the end either this way or that way,  but one thing I'm sure, your bank account will be depleted long before the end

[Webby the Bear]

Yes and if Webby goes that route he'll also be faced with all the steering mods and chassis mods that you've been deliberating over for months

Let's start simple for Webby's first learning project, eh?

 

[cem_devecioglu]

first, you have Kevin Wood handy

Yes, but, despite that, it worked.

second, most tuners prefer initial session on the dyno for the car to run because tuners prefer biggest injectors possible which requires creating a map from scratch    after the car reach "normal" working state , fine tuning done on the road

True. Most tuners would prefer you to pay by the hour to use their rolling road.

I started out with a rough ignition map which was what I was using with the DCOEs that were previously on the engine. I had no fuel map whatsoever, in fact, I wouldn't be surprised if I was the first to run a megasquirt on a Zetec engine. I also used Jenvey individual throttle bodies running Volvo 940 Turbo injectors, so it was a bit of an odd combination anyway.

My approach was to calculate the fuelling requirement for the engine power I expected, turn that into an approximate injector duration and calibrate the whole system using that as a baseline for 100% VE. I'd observed that around 30% VE at idle is typical, so I shot at that and had it idling OK with a bit of tweeking. I then increased the revs off load and got it able to rev unloaded to the red line cleanly. I then "interpolated" the valves in the map from unloaded up to 100% VE and tweaked the acceleration enrichment until it'd rev cleanly. That's about all I could do without hitting the road.

Fortunately, I had a short downhill stretch of road before I could turn onto a main road and drive for 10 miles or more. I gave the closed-loop fuelling a lot of authority to correct the fuelling (by up to 50% IIRC) and set off. It drove like a dog, of course, but if you held constant speed and load for long enough for the closed loop fuelling to adjust you could watch the correction and decide how far you needed to adjust the map to correct it. A few manual corrections of the map and it was perfectly driveable. After about 30 miles it was almost perfect - better than the carbs I was running before, at any rate. It had a little more tweaking in the following months, but more than 10 years later it's still running perfectly!

Maybe I could get another few percent out of it on a rolling road, but I know that the tune probably varies enough with temperature and altitude / atmospheric pressure at the moment that that would probably be futile. Maybe one day I'll tune the correction for these well enough that I'll have a go at fine-tuning the map...

What I would say is that tuning the fuelling on the road is easy. You can tell through the "seat of the pants dyno" when you've hit the sweet spot and readings from a wideband lambda sensor can give you confirmation of that. Tuning ignition timing is much less easy, and I reckon a dyno would help greatly in getting that completely optimised.

good one Kevin.. 


what were you using map sensor or maf ?

[Kevin Wood]

good one Kevin.. 


what were you using map sensor or maf ?

I'm using speed-density, so MAP sensor for the primary load input. As I'm using individual throttles, a MAF wasn't going to be easy without a big airbox. Most people use Alpha-N in such a scenario (TPS as primary load input), but I decided to be different.

Actually, SD works quite nicely, because it gives you better resolution on the fuelling at light throttle openings, which is important when you have 4 big throttles. A little throttle angle gives a big change in airflow!

[Webby the Bear]

Although seriously, it does have to be an auto for young bear.

 

[Webby the Bear]

Although seriously, it does have to be an auto for young bear.

 

...unless anyone would care to volunteer to change gear for me everytime i wanted to go for a drive?

[Kevin Wood]

Although seriously, it does have to be an auto for young bear.

 

...unless anyone would care to volunteer to change gear for me everytime i wanted to go for a drive?

That could make for some comedy moments.