Astra Coupe Turbo 273bhp, but 25bhp less power with WI. - Page 4

Richard L · #31 07-12-2005, 12:23 AM

I remembered you making a bar graph unit on your dash, nicely made unit. I wonder if you have solved the LM3914 overloading issue by reduing the drive current to the LEDS.

I think it will be useful for Mike to have one of those to monitor his lambda values as we start to modified his MAF signals. Care to share the circuit?

Richard

Quote:

Originally Posted by PuntoRex

hmm....

As I see in my homebrewed O2 signal display, in the mid-high rpm range, the up-down voltage sweeping is pretty quick. At 4500rpm or slightly above, if throttle input is small, the engine is still in close loop. At this stage, the voltage is bumping up & down quickly. If the padel is depressed, the signal will go high & stay. I think the reaction is quick enough.

If the exhaut gas monitoring-feedback system is too slow, how can it catch up with changing load & keep the a/f right?

PuntoRex · #32 07-12-2005, 02:58 AM

Circuit diagrams:

http://www.taunus-biker.de/~mdvp/Lambda/Lambda.html

http://www.fabrio.it/puntogt/tecnica/lambda.htm

They are not in English, but supposedly the diagrams should be easily understood.

LM3914's datasheet:

http://cache.national.com/ds/LM/LM3914.pdf

About the LED current, haha, I fried some chips. I like them bright :twisted: Right now I attach a heatsink on it. Hope it helps...

JohnA · #33 07-12-2005, 11:46 AM

Guys, these are all displays of the narrowband signal.
Quite useless at the sort of revs/load we're talking here.

Richard, of the three signals you mention I'd only fudge the AFM a bit (only at revs/loads where it runs open loop ofcourse!)
In fact I'm doing this on the supra, gaining an extra 5% power (at a minimum)

I'd avoid fudging the CTS signal because of the risk that the ECU decides to swap maps altogether. Not good.

Richard L · #34 07-12-2005, 09:54 PM

narrow band can be used for reference - but better to run on the rich side of 14.5 afr than leaner. It is quite possible to tune to 14.5afr and than richen it up a little.

Although the curve is non-linear, we can see voltage variation between 12.5 to 14.5. I agreed, is not ideal.

Richard

Quote:

Originally Posted by JohnA

Guys, these are all displays of the narrowband signal.
Quite useless at the sort of revs/load we're talking here.

Richard, of the three signals you mention I'd only fudge the AFM a bit (only at revs/loads where it runs open loop ofcourse!)
In fact I'm doing this on the supra, gaining an extra 5% power (at a minimum)

I'd avoid fudging the CTS signal because of the risk that the ECU decides to swap maps altogether. Not good.

K3FUS · #35 09-12-2005, 05:19 PM

Mike

How is your jet held in the air pipe? Mine was in an in pipe "gromit" and because it did not seal I had less BHP but no change in LBft due to the air loss.

I'm about to use my WI to spray the cooler (I now have the same one as you and the same turbo and map). I know ho effective spraying the cooler is as I have seen it on Courtenay's RR ( reduction of about 20 deg C at 6k rpm).

MikeWarner · #36 09-12-2005, 06:29 PM

Hi mate. Now you are running pretty much the same spec as me, do you also have the dip in power like me?

Re. the jet gitting, I had a section of alloy welded onto the pipe (thanks dad), then drilled and tapped that - it does seal, no worries there. The loss in power can be seen by turning the system on and off, so it is nothing to do with bad installation.

I have the bits to plumb in a second jet, which I will do once these existing issues are rectified. I will most likely spray onto the IC too.

As above, I'll be moving the primary jet to a point after the inlet temp sensor and Richard will be working on "fudging" the AFM signal.

K3FUS · #37 10-12-2005, 06:40 PM

Mike

Only fitted the FMIC Thursday so not run the car on the RR yet.

Speaking of the RR, I know that spraying the I/C reduced my inlet temp from 65 to 37 deg C with my SMIC, this is why I am taking the alternate route.

I would not recommend altering the AMM reading, but if Richard thinks it will help then go for it.

MikeWarner · #38 13-12-2005, 07:47 PM

Richard, sorry about the delay, but I found my mulitmeter and I can now report of the AFM voltages.

At idle the car sits at an AFM volage of 1.37. When booting the car, the upper limit I saw was 4.93v, so very close to the maximum 5v.

I hope this helps.

Oh, any chance I could pop up at some point please to reposition the jet as I don't have the tools available to do this? Basically all that needs doing is blocking the current location with a blank, and drilling a tapping a plastic pipe the other side of the temp sensor.

ashtal · #39 13-12-2005, 08:52 PM

Has there been anyone with a sucessful 1s kit on an astra turbo or any z20let ? I who of a fair few people who have WI on there car but no reals gains ! Richard from a turbo car running around 250 - 270bhp Should you see much improvement in bhp / torque with an 1s kit ?

Richard L · #40 13-12-2005, 09:06 PM

The MAF sensor voltage is goodto be played with.

No problem, which day do you have in mind?
I cannot do Wednesday. Thursday or Friday is OK.

Richard

Quote:

Originally Posted by MikeWarner

Richard, sorry about the delay, but I found my mulitmeter and I can now report of the AFM voltages.

At idle the car sits at an AFM volage of 1.37. When booting the car, the upper limit I saw was 4.93v, so very close to the maximum 5v.

I hope this helps.

Oh, any chance I could pop up at some point please to reposition the jet as I don't have the tools available to do this? Basically all that needs doing is blocking the current location with a blank, and drilling a tapping a plastic pipe the other side of the temp sensor.