ELECTRONIC CIS fueling & BOOST control

[911nut]

Originally Posted by Thierry25

Hello Paul

Smurfbus is correct. I don't use LM-1 but LM3 aux box .

I took the RPM signal directly on the wire behind the tachometer.

I have the LM-1 with RPM adapter.
I'm pulling a signal from the black/green wire on the 6 pin plug under the driver's seat. It's 10.5 V at 0 rpm, dropping to 4 volts at 6000 rpm.
What I'm struggling to do is make sense of the configuration table for rpm on the LM-1.
Did you have to configure the auxbox for rpm and what parameters did you use?

[Thierry25]

Here are some results ….


Firstly, it is interesting to see , that keeping the same turbo , same wastegate with same spring (0.8b) , the " before and after " MAP curves exhibits a little difference.

This turbo provided about 0.85 b of boost pressure into the previous setup ( little increase along the rpm), now the boost pressure is totally flat and is around 0.79 b only.



As can be seen either, even with new larger cams & larger intake, the turbo reach 0.8 b at nearly the same RPM . ( Maybe 100 or 200 RPM higher only)


Here is one comparison between with and without "CIS controller" . In both case , there is no extra boost ( wastegate regulation @ 0.8b only ). As said before, the car is fitted with the FVD advance timing plate + RPM switch which allow me to add 3° or 6° on the stock timing. In this example, the curve with stock CIS ( no CIS controller) was made with 6° more below 4200 RPM , 3° more between 4200 and 5600 RPM, and 6° more at upper RPM. The curve with the CIS controller was made with + 6° everywhere.





So far, without the CIS controller it is too fat everywhere ! ( but it’s normal, I have 044 fuel pump in front )

The benefit of the CIS controller + 3° more advanced timing ( in the range 4200-5600 only ) can be seen !



My datalogger estimated power & torque are a bit pessimist. Actually , with this same adjustment ( 0.8b only) , 430 HP have been obtained during the dyno session.

[911nut]

Originally Posted by 911nut

I have the LM-1 with RPM adapter.
I'm pulling a signal from the black/green wire on the 6 pin plug under the driver's seat. It's 10.5 V at 0 rpm, dropping to 4 volts at 6000 rpm.
What I'm struggling to do is make sense of the configuration table for rpm on the LM-1.
Did you have to configure the auxbox for rpm and what parameters did you use?

So Thierry, can you respond to this, please?

Thanks.

[Thierry25]

Originally Posted by 911nut

So Thierry, can you respond to this, please?

Thanks.

Hello Paul

In my case (LM3 auxbox) + wire from tachometer , I simply used a straight 5V = 10500 RPM (instead of initial 10230 ) and 0V= 0RPM

Seems correct at idle and quite close to reality at high RPM .

[911nut]

Originally Posted by Thierry25

Hello Paul

In my case (LM3 auxbox) + wire from tachometer , I simply used a straight 5V = 10500 RPM (instead of initial 10230 ) and 0V= 0RPM

Seems correct at idle and quite close to reality at high RPM .

Ahh.
I will give that a try.
Thank you sir.

[race911turbo]

Originally Posted by IMONBOOST

Ok, all done and car fired up with no problems, will probably start testing and tuning on the weekend, there is a tropical storm coming so no time to take the car out. Here is the outcome, I will be posting the exact parts I used although machine work was required as I stated on the above post, so not exactly all off the shelf parts. This setup will only work on cars with the aluminum Fuel Head.

nice.

[race911turbo]

Originally Posted by IMONBOOST

Ok, all done and car fired up with no problems, will probably start testing and tuning on the weekend, there is a tropical storm coming so no time to take the car out. Here is the outcome, I will be posting the exact parts I used although machine work was required as I stated on the above post, so not exactly all off the shelf parts. This setup will only work on cars with the aluminum Fuel Head.

I found this from my turbo supplier, it is $60 each.

[race911turbo]

When I got my 930 turbo and 965 turbo motor I went straight to EFI, When does factory FV turns on?

[Thierry25]

Originally Posted by race911turbo

When I got my 930 turbo and 965 turbo motor I went straight to EFI............

Unless you want to get more than 600 fwHP , I don't see any interest to swap for EFI ....

[Thierry25]

Originally Posted by race911turbo

When I got my 930 turbo and 965 turbo motor I went straight to EFI...

Unless you want to get more than 600 fwHP , I don't see any interest to swap for EFI ....

[race911turbo]

When and how does factory FV turns on?

[Thierry25]

Sorry, but I do not understand exactly your question ...

In my case, the stock FV is still used in it original function (lambda regulation) together with the kjetronic module.

The additionnal FV is wired to an AIC . It allow to adjust the CIS control pressure according the RPM and MAP

[Thierry25]

And here are the results with RPM boost management




The boost level is adjusted to nearly 1.3b until 5000 RPM. Beyound this, it is tappered step by step to reach arround 1.1 @ 6000 RPM

Any additionnal boost increase ( I mean from this MAP curve) in the range 5500 to 6500 doesnt provide any additionnal power. ( 1.2 bar @ 6000 even start to hurt the power curve and convert it into heating loss .... it can be seen on the dyno curve below )

No doubt, I reach here the limit of this turbo : especially the limit of the hot side ... not so bad anyway

The AFR is adjusted to a flat 12.5 curve. I still have some margin under 5500 RPM. But past 5500, the system is set at it maximum. Some additionnal fuel could be found by using C2T 3.6 injectors and by installing a bigger rear fuel pump.... but in my case, as I reach the limit of the turbo, it is useless.

There is absolutely no sign of knock ( even during some 35°C testing session ). I even do not need to use the RPM switch to reduce the additionnal timing (6°) which is provided by the FVD sensor plate.


Here is the dyno curve




496 FWHP @ 5400 RPM
669 Nm @ 4900 RPM

[911nut]

Originally Posted by Thierry25

The AFR is adjusted to a flat 12.5 curve.

Bravo, Thierry.
I've long maintained that our boosted, air cooled engines can run at 12.5/1 without detonation. As long as the output of the compressor doesn't move over the choke line of the map, maximum safe torque will be achieved at this mixture. It's also good to see that the 6 degree advance has no detrimental effect either.
Looks like the future direction of mods to my car has been established

[Thierry25]

Originally Posted by 911nut

Bravo, Thierry.

Merci Paul !

[DA VINCI]

Thierry, How is this new setup going?.

I am very interested in this evolution, because I am planning to optimize my K-jetted 965 as well. I have some questions about this engine and your experiences:

Have you maintaned the dilivar head studs or you went to uprated ones?. Could you tell us a bit more about the minor leaks you had on the cylinder to head union before the 2011 set up?. From what power/torque/boost do you recommend the flame ring on a standard 3.3 engine to be fitted?


Congratulations for your methodical work, it's really inspiring for a lot of us.

[911nut]

Originally Posted by DA VINCI

Have you maintaned the dilivar head studs or you went to uprated ones?. Could you tell us a bit more about the minor leaks you had on the cylinder to head union before the 2011 set up?. From what power/torque/boost do you recommend the flame ring on a standard 3.3 engine to be fitted?

Thierry, yes, I'm curious to hear the story on this as well.
Also, do you have any intake temperature vs. boost level data available?

[Thierry25]

Originally Posted by DA VINCI

Thierry, How is this new setup going?.

I am very interested in this evolution, because I am planning to optimize my K-jetted 965 as well. I have some questions about this engine and your experiences:

Have you maintaned the dilivar head studs or you went to uprated ones?. Could you tell us a bit more about the minor leaks you had on the cylinder to head union before the 2011 set up?. From what power/torque/boost do you recommend the flame ring on a standard 3.3 engine to be fitted?


Congratulations for your methodical work, it's really inspiring for a lot of us.

Hello

Thank you very much for your kind words. It is my pleasure to share and to learn on this board.

I use the dilavar head studs on my engine. But these studs have been installed 3 year ago and from what I understood, this was a new generation of dilavar. ( With very old stuff, I think it is risky to increase boost & max TQ point since these parts can fail quickly and without any prior notice )

So 3 years ago, we did the complete rebuild but my mechanic thought it was not necessary to resurface the head & top of cylinder. ( We just put the new stock head gaskets ) This was a mistake ! At that time I also didn't make the flame ringing. As soon as the engine was re-assembly it made some minor leaks (even at regular 0.8b of boost & quiet driving during the break-in period ).... whatever the boost pressure , the leaks were the same. I mean I didn't get more leak with higher boost pressure (even with 1.5 !) It was never a problem to increase torque & power....just a little upset to see some minor oil leaks on a new engine but not a huge issue.

This year, while we did the new setup, we did a nice head re-surfacing + machining for flame ringing. Until now ( about 5000 km since ) it seems there is no more oil leak !

Just my 2 cents:

If you are about to rebuild your engine and add some torque& power (even low medium setup) , I recommend you to re surface your head & cylinder top and to go with flame rings. Somewhere, the flame rings itself won't prevent the oil leak. But the way to do it will ! The idea is to have a total groove height which is very lightly inferior to the ring height. Thus the contact between the ring and head is lightly compressed after torquing ( while the regular head /cylinder surfaces are perfectly in contact each other too) As you can understand, the success of this assembly rely on high accuracy re-surfacing job with a perfect ring matching & machining accuracy and a perfect torquing. Of course, new dilavar head studs is a must do.

[Tomy]

Thierry,

I agree with you fully. I had have no leaking engine ( with 150T km on it) with original set up. I only put new k7200 Turbo instead original and Brian raryl8 muffler and problems start after 50 km on it!
Oil start leaks between head and cylinders so it finally finished with engine rebuilds with re surface heads & cylinders top. I didn't add flame rings as I don't like increase power and torque more. New dilavar head studs is on place too. My opinion is that every increasing of P&T should be make with respect as above.
My personal experience and my money...

[Thierry25]

Originally Posted by 911nut

Thierry, yes, I'm curious to hear the story on this as well.
Also, do you have any intake temperature vs. boost level data available?

Hello Paul

No sorry, but I still plan to do it ( It is even pre wired but a big lake of time until now )

In my case, I don't think the IAT affects too much the performance. But I am sure the hot side of the turbo is too much restrictive for the upper RPM range. Thus I must deal with it and above 5000 RPM I must reduce the boost level quickly. Not because the IAT itself but just because higher boost pressure leads to lower HP ! ( too much back pressure)