The 2.7L thread

[HANDBLT]

Looking great. You going to shoot the whole car that color or just the engine compartment? Thats a great color.

Did you have that oil cooler made or is someone making those?

Also how was your experience mounting up the S38 TBs?
My set is still in a tupperware tub after I took them out of my sonic cleaner.
I keep saying Im going to start mocking them up on one of my engines on a stand in the basement.
Any advices???

Thanks Jimmy. That was just phase one of the paint. Since the engine was the first phase, I painted it while the engine was being built. The rest of the interior will be done the same, and then the exterior will get the Michelin livery in the next phases. I am building the Michelin Alpina DTM car. Not an authentic replica mechanically but the paint will be as close as possible.

Mario sourced the heat exchanger, ping him for the particulars.

The TB's were a fiasco for me. I sourced what we thought were 50mm S38's but they ended up being 46's. I then sourced the Jenvey's as the fix, but if you look in the Flickr pics you will see the problem with them on a high CFM motor. The head size is the same as the OEM 46mm TB;s from the S14 and there is no meat there to bore them out. We had to bore out the 46mm S38's to 48/49mm and use them. They mount right up to the head and the 50mm 8 injector airbox from John does as well. Probably just move to slide throttles one day, to get rid of the tumbling of the air after the throttle plates that causes issues on engines of this magnitude. That or add DBW to remove the huge dip in the power lower in the revs due to reversions in the airflow at full throttle lower RPM's. Ever notice how these cars 'feel' more powerful and smoother on power delivery with part throttle in that area as opposed to WOT through those areas? The EMS that I am using (Emtron) will have the ability to do all this along with the active knock, TC, and MK60 ABS that comes in later phases.

T

[jimmy p.]

Thanks Jimmy. That was just phase one of the paint. Since the engine was the first phase, I painted it while the engine was being built. The rest of the interior will be done the same, and then the exterior will get the Michelin livery in the next phases. I am building the Michelin Alpina DTM car. Not an authentic replica mechanically but the paint will be as close as possible.

Mario sourced the heat exchanger, ping him for the particulars.

The TB's were a fiasco for me. I sourced what we thought were 50mm S38's but they ended up being 46's. I then sourced the Jenvey's as the fix, but if you look in the Flickr pics you will see the problem with them on a high CFM motor. The head size is the same as the OEM 46mm TB;s from the S14 and there is no meat there to bore them out. We had to bore out the 46mm S38's to 48/49mm and use them. They mount right up to the head and the 50mm 8 injector airbox from John does as well. Probably just move to slide throttles one day, to get rid of the tumbling of the air after the throttle plates that causes issues on engines of this magnitude. That or add DBW to remove the huge dip in the power lower in the revs due to reversions in the airflow at full throttle lower RPM's. Ever notice how these cars 'feel' more powerful and smoother on power delivery with part throttle in that area as opposed to WOT through those areas? The EMS that I am using (Emtron) will have the ability to do all this along with the active knock, TC, and MK60 ABS that comes in later phases.

T

Well Tony I can say that I can relate that no great idea goes unrewarded without becoming a complete fking project.
That is very sad news about the Jenvy throttles. So the throats at the head were really no different than a standard 46mm street TB?
Thats so sad.
I would have hoped they would at least do it the way the factory did it, before they homologated the 48mm TB they had the cheater TBs with the big throats at the head.
I have a set on my Gruppe A car. Really neat part.

The paint part makes perfect sense, I cant wait to see it painted. Thats going to look great. Thats a good livery.
Keep posting updates, fun to follow.

[stevesingo]

That or add DBW to remove the huge dip in the power lower in the revs due to reversions in the airflow at full throttle lower RPM's. Ever notice how these cars 'feel' more powerful and smoother on power delivery with part throttle in that area as opposed to WOT through those areas? The EMS that I am using (Emtron) will have the ability to do all this along with the active knock, TC, and MK60 ABS that comes in later phases.

T

I did some logging on my EMS and anything above 70% throttle reduced torque in the 1500-2100rpm range. I too have thought of DBW to deal with this. For example 1700rpm 100% pedal demand = 70% throttle angle. You could also linearise the torque vs pedal demand which could help drivability.

[HANDBLT]

I did some logging on my EMS and anything above 70% throttle reduced torque in the 1500-2100rpm range. I too have thought of DBW to deal with this. For example 1700rpm 100% pedal demand = 70% throttle angle. You could also linearise the torque vs pedal demand which could help drivability.

Bingo bango. It would take some logging of all angles at 5% intervals vs duty cycle to smooth it out, but it’s there. I’ve felt it since the first time I ever got to know one. It always felt better at at certain throttle through the gears other than WOT. Actually I can feel it in a bunch of different cars I’ve learned.

I can’t wait to play with that one day with the new EMS.

T

[HANDBLT]

I did some logging on my EMS and anything above 70% throttle reduced torque in the 1500-2100rpm range. I too have thought of DBW to deal with this. For example 1700rpm 100% pedal demand = 70% throttle angle. You could also linearise the torque vs pedal demand which could help drivability.

Are you logging RPM/SEC vs RPM to see the torque curve? Remember Stan? That old FJO with palm pilot he turned me onto had this as a data log (one of 4 I think lol) and it’s what I used to tune the Link MAP, old school split second, and all the others I played with, and that’s what verified it for me lol. I always felt it just needed data to prove it.

T

[stevesingo]

Simpler than that. Given fuel injector pulse width is a function of VE, above 70% TPS at 1700rpm pulse width drops for a given lambda value.

If you are using MAP compensation, you can log the MAP sensor at high frequency and see the reversion pulses screw with the MAP.

RPM/sec should work in theory. How does wind direction and road gradient/bumps effect the data?

[JimK]

At part throttle settings, the effective intake runner length for the reflected air pressure wave is different than at WOT (because of the butterfly obstruction in the air flow path) and may have a play in air mass thru the engine. My logs with a Haltech Elite show an actual loop around trace of the gmsAir/cylinder at certain mid rpm speeds at WOT.

[HANDBLT]

Simpler than that. Given fuel injector pulse width is a function of VE, above 70% TPS at 1700rpm pulse width drops for a given lambda value.

If you are using MAP compensation, you can log the MAP sensor at high frequency and see the reversion pulses screw with the MAP.

RPM/sec should work in theory. How does wind direction and road gradient/bumps effect the data?

Exactly that was the challenge. Found a perfectly flat piece the road With no dips so that I can ring out third gear to do my tuning by. It had a pretty good smoothing factor that would help out a lot.

T

[nilsp]

Bingo bango. It would take some logging of all angles at 5% intervals vs duty cycle to smooth it out, but it’s there. I’ve felt it since the first time I ever got to know one. It always felt better at at certain throttle through the gears other than WOT. Actually I can feel it in a bunch of different cars I’ve learned.

I can’t wait to play with that one day with the new EMS.

T

I've also felt this with the throttle angles, ever since my first e30 325i (actually on my mothers audi 5e too, they had a natural "step" in the pedal somehow)

I did install dbw last year, but not had much time adjusting it, and for me it isnt natural to "floor it" anyway.. but if getting this right it can be a nice feature.

Attaching a screenshot of my "map" for the pedal. This isnt fine tuned, just a quick setup.
Also on the logging discussion.. I took a look at the injector pulse log vs something called actual load, which is the actual VE in my link ems.. they follow exactly,like Steve said.

And I attached a log of map sensor (using voltage to get high resolution)

Just to add to the discussion..

-I find this very interesting, and learn every time I read through these kind of threads.

[super7]

I did install dbw last year, but not had much time adjusting it, and for me it isnt natural to "floor it" anyway.. but if getting this right it can be a nice feature.

Where did you mount the dbw engine?


Regards Nils-Erik

[nilsp]

Where did you mount the dbw engine?


Regards Nils-Erik

I made a bracket behind alternator, bolted to the block.
But I quit that project (it worked) due to too much new things on new car..

NilsP

[Dave @nz]

Not my M3 just some inspiration for dbw, running Heltech ECU from memory.

[jimmy p.]

Alot to digest in that photo. There is a bunch of cool trinkets in there and some nice looking preparation. Any more details on that build?

[Dave @nz]

Alot to digest in that photo. There is a bunch of cool trinkets in there and some nice looking preparation. Any more details on that build?

I had a quick talk to the owner 2.5l from memory running Heltech ECU with the electric throttle motor, piro sensors in the headers which are for tuning, if the engine develops misfire or rich lean condition on one cylinder during the race ecu scales back performance to protect the engine. Also bell housing adaptor plate made for different gearbox 6 speeds cannot remember the details.
Apparently the throttle motor has adjustments or damper so it can keep up with fast foot movement. Owners business is on the rocker cover.
I do have more photos if required but no close ups of the throttle motor

[proctor750]

I like his bulkhead mount for harness pass through. We did something similar. What's the little vaccum actuated deal on the firewall?

Also:
-Link Extreme ECU with custom harness built by Neel at APEX

^^ how is this working out for OP? I was trying to go Life ECU with franz but the dude just dropped off the face of the planet. Would like to get pricing info as well..