Ducks964

Just an update - supercharger install was completed, but had serious oil leaks at start up. Looks like mostly coming from timing chain cases to engine. Started the process of pulling off both chain cases and replacing o-rings and seals. Will go ahead and replace several other possible oil leak areas while I am in there. Hopefully everything will be back together in the next few weeks and I can provide feedback on the supercharger.

Ducks964

Here is at least what the install looked like.

STUARTQ

Looks like you've done a very good job. Looking forward to hearing about the performance.

Ducks964

Thanks. Definitely the instructions left a lot to the imagination. However overall it was not too bad, just time consuming. After doing it once, it is not hard to pull off and reinstall when needing to get to the top of the engine.

What takes the extra time was to find out the bypass actuator was shot and needed to source a new one, and fitting the intercooler, pump, and lines without the hoses pinching and allowing enough room for the AFM. I must have removed and reinstalled the intercooler about 50 times to get it right. Also had a time with the bracket that holds up the front of the supercharger. It took me days to come up with a plan to stop it from backing off and rubbing the pulley.

Definitely it has been a large learning experience. Looking forward to getting it back together and on the road.

Bud Taylor

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Eric_Oz_S2

I see you used a unichip system - is that plugged into the dme rom slot? You also said that you had it reprogrammed. Are you going to get it programmed on a dyno post install? I hope so, as the chances of getting it 100% without doing this approach zero.

Another option is to use an ostrich ii emulator and tuner pro to dial in the fuel and ignition curves. I did this or my 944s2 supercharger install. The s2 uses the same motronic as the 964. Also, as you are running in closed loop using nbo2 emulation you will find that the pt maps run a little lean for a supercharger installation as they always aim for stoich. The problem is pt to wot transition where there is a fuel enrichment delay when the engine suddenly hits boost. I found there were quite a few knock counts running closed loop on the track, though ok for street. In the end I installed a switch to activate the non-cat variant maps and use this most of the time. At stoich afr I always found the car would be a little jerky at low throttle resulting in some shunting in the drivetrain.

You should also aim for low 11s afr at wot and boost over about 5psi. Even though you won't get max power here it will save the engine by keeping combustion temps down. You should also check for knock and have the ignition timing retarded to suit.

if you need any help with the motronic let me know. It's not hard to tune once you know how they work.

Oh, what you will also find is the afm will probably get to its limit before rev limit, which means the maps get a bit funky.

What size injectors are you running?

Cheers

MPB993

Hi Duck,

I think you will just love the torque. My 993 tip has now done 75k miles on one of the early TPC kits. Kit was installed by 9M along time ago. I have upgraded the injections, up'd the boost a little on a single 7th TPC injector. I have been running water/methanol injection (50:50 mix) throughout, a wideband meter and a knock watcher. There is a little afm mismatch between cylinder banks due to only a single 7th injector which I think has been ironed out by using the 2 injectors and unichip. I have been running 12:1 afr without problems but only on the w/m injection.

Biggest learning point over the years has been to add a cold air intake on my setup as the engine bay gets warm in traffic which was not good for ecu retard resulting in cylinder overheat and knocks once traffic cleared. You may not have this issue due to the chargecooler.

Mark.

Ducks964

Hi Eric_Oz_S2 - the Unichip is tied into the AFM and Crank Sensor. With a separate air pressure sensor, the Unichip controls the firing of 2 extra fuel injectors. I am not if anyone has had further tuning done than the maps that are part of the kit. I did get an extra Unichip and have downloaded the 964 maps to it (originally set up for a 993). A friend has the Tuner Pro that we may look at after the install, but the Unichip piggyback may not work well with tuning the Motronic.

I am running stock rated upgraded injectors (4 port). I may try running without O2 (I have the correct plugs) if the PLX shows that the afr's are too high.

Hi Mark - do you have any details on your cold air intake. I just have a cone filter which will just pull in air at the temp in the engine compartment. I do have the intercooler and may not have an issue, but still interested on how you have the cold air intake.

JasonAndreas

M2.1 has a few correction maps for fuel enrichment based on load/rpm and the change in load. The 964 ECU also has support for a pressure sensor that you could feed into a fuel enrichment map.

Ducks964

Thanks Jason. Do you know where I could find some info on this option? Would like to see what can be done with the motronic.

Eric_Oz_S2

Adjusting the accel enrichment maps didn't fix the issue on the s2 (same m2.1 motronic). That might be because i run the afm before the SC and when the throttle opens there is a delay between the bypass valve opening/pressure wave entering tb and the afm picking up the overswing. Feeding it with a map signal would be a good idea, but this would require a code rewrite.

Using 2 supplementary injectors and a piggy back is not the right way to tune an engine. You would be better off finding someone with motronic tuning experience and upgrading the main injectors. You could try the piggy back program as a start and see how it runs, but I would be very careful and monitor afr before running it too hard.

It's also worth installing a knock counter or knock light. Vitesse racing makes these (v-knock). Talk to John about this. I have found that being able to monitor knock on a supercharged engine is a valuable tool.

Cheers

JasonAndreas

Actually there are no code changes required, you can do it with just maps.

Eric_Oz_S2

Jason

That sounds interesting. Do you still keep the afm in this case, or do you rewrite the map headings to scale for a map input signal?

alexjc4

Jason, when you say "pressure input"; is that just an ambient pressure input to properly calculate the air mass from the air volume measured by the vane afm (in addition the the air temp)? I assume the m2.1 doesnt have the latent ability to run blended maf+map.

I have a rom emulator which i have used on othe cars and i found an address file to use in tunerpro for the 964 a few years back, but the completeness of the address file seemed dubious so i have never tried it. Jason/Eric what's the most authoritative source for a m2.1 address file for the 964 (i assume the addresses are not identitcal to the 944 m2.1)?

Eric_Oz_S2

I downloaded the .xdf Tunerpro definition for the '92 964c2 from Tunerpro. You are right, the adresses between the s2 and 964 are not the same, but they are surprisingly similar. It is obvious they were developed around the same time and seem to have the same functions. Just for interest sake I looked through the 964 code and almost all the maps are within a few bytes of where they are for the s2. The tunerpro xdf on the web is OK, but it is missing injector lag, dwell has the wrong conversion, it is missing the accel enrichment, all of the AIT and TMOT maps etc. Having said that it has most of what you need for basic tuning except the injector lag which is needed for changing injectors.
Unfortunately I don't have a 964 so can't confirm the maps are correct, only by comparision to the S2 maps.