No, I was explaining how to properly do this, giving away the secrets of how I could make a ($$) product, and offering to help out with the xfr function of the MAF (which I have and y'all don't have) because I like to use up oxygen Jim
Next step is to find the characteristic curve of the MAF. Because I will use two 5.2 MAF I need the curve which is embeded in the Motronic to perform the voltage/flow and flow/voltage conversions. I do not know how or where to read in the ECU flash memory so I will proceed a different way : disconnect the MAF, apply and measure a variable voltage at MAF connector and read the corresponding flow using my OBDII reader. A good DMM for the voltage and hex values (16 bits) for the flow should give an accurate enough calibration curve. What do you think Jim? I will try that ... except if you agree to PM me the curve you have ;-)
Yes ... but only in my brain and on my laptop. Electronic diagram is almost complete and the components are on the way. Today, I received the second MAF. Now, I have to dump the MAF calibration curve from the Motronic and see how to manage it in the software. Anyway I will not do anything on the car before I have built and validated the signal converter/combiner. Also, need to find hoses, connectors, ... etc! A few weeks of holidays , a lot of work right after, ... I don't see any real testing before september. I'll keep you informed!
I resurrect this thread because I am almost there now. It took me much much longer than expected to find, collect and modify the parts, and the time (!), but I was finally able to make the first installation of the set-up this WE. - Airbox covers are modified 5.2 ones, I have not been able to find 2.7 covers at a reasonnable price to try such a mod. It took me a lot of time to locate a set of cheap ones, but also to adapt the air output with the correct diameter and with the good geometry. I am not particularly skilled at aluminium welding ... I even tatooed my left hand in the process ... - MAFs are genuine Bosch parts, HFM2 type, and able to measure up to 640 kg/h (single 5.2 MAF is OK up to 1040 kg/h) - MAF combiner H/W and S/W are ready. Among other components (microcontroler, Digital/analog converter, Op amplifier, ...) it uses 2 EEPROMs which contain look-up tables (LUT). The first one (1) contains the LUT for the new MAFs "voltage-to-flow" characteristics, the second one (2) contains the LUT for the 5.2 big MAF "flow-to-voltage" characteristics. These LUT are still to be calibrated. So far I have tested the MAF combiner on the table with linear LUTs. - there is no modification of the car harness. With the combiner in the engine bay (with space qualified heat insulation ) the only interfaces are the 5.2 MAF connector and a short extension for the air temperature probe. Still to be done is : - to calibrate the LUTs. For that purpose I will use a different set-up (soon a picture) which will allow me to run the car with the 3 MAFs in the intake air path (the 5.2 MAF being still used by the Motronic). I will then record the output voltage of the 3 MAFs and air flow thanks to the live OBD data. Once the LUT calibrated, I will check with the same set-up that the output of the MAF combiner matches exactly the output of the 5.2 MAF. Last step will be to run the car on the MAF combiner output with this test set-up, before the final configuration. - to finalize the harness - to make an air pickup after the MAFs, in 1 (or the 2) bellows, in order to feed the idle regulator - to paint the covers The MAF combiner has also an input to acquire the throttle pot voltage. Later on, in a second step, I will use it to detect when the Motronic is working in open loop, and then try some tricking of the MAF voltage under the monitoring of a wide band O2 sensor. I don't know at all if there is any horsepower to gain there but I think to this set-up for so long now that I have to try it and go to the end of the story. May be I will be back to the original configuration soon but at least I will know why. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
I can't wait! I'm glad someone had the nuts to do it, even if there is no gains. You still are one up in my books.LOL
Mmm very interesting project I would suggest that you use or get to gether with Goth to use the "Goth" air flowed airbox lids to produce maximum yield. One can see how restrictive the standard covers are, the air flow on standard covers are terrible. The Goth covers have been proved to yield good results. So your set up with the Goth set up would be a great yield IMO (love that word "yield" today).....Yield!!
Great job Eric!! I like how you used the original cover outlets and tied them together so that each cylinder bank has access to both air cleaners at all times! It will be cool to see what voltage curves signal differences the data logger records between the two MAF configurations . You should see some 'top end' gains at minimum ! lol .............. true that zero! The factory covers on the 5.2 version are indeed restrictive ............ when I did my intake cover mods with stock exhaust, I saw a 5-6 RWHP gain at 'top end' RPMs ! Though for some reason on my Dyno test ......... which may or may not come into play on Eric's dual set up ....... was a slight drop in 'mid range' power . The main reason for that was the size/shape of the stacks I used initially, which were too large for the 355 application. They had huge flow up top but they lost a bit of 'velocity' at lower air demands (ie mid-range ). So because of that I am currently redesigning the shape of the stacks inside 'new covers' to find a good medium of 'top end flow' while maintaining 'mid range' power .
Great work! It's rare to see someone in the Ferrari world do what those in the Porsche and other tuner worlds do! Improve their cars! Can't wait to see dyno numbers. If they're up respectably I hope you'll have people knocking at your door with $$$ asking for your system. I've gotta get back to finishing my project to get more air into that engine! Image Unavailable, Please Login
Thanks! I appreciate the comment from another mod experimenter Connecting the 2 airboxes is the easiest solution to use the original outlets. I don't know yet if it can have any effect but one can also consider pluging them or, why not, putting a valve in between the boxes and commanding it according to the running conditions ... I will start the calibration job soon ... but I have first to enjoy a bit my car after a so poor weather period in France.
WOW ... obviously we don't play in the same category Great modification. Have you made any internal modification of the engine? What level of boost do you plan? The turbos look big for a low boost/ high compression engine. What engine management system will you use? The MAF will be overloaded very quickly, which one will you use (993 turbo?)?
So slow ... but still on the track! First picture shows the calibration set-up. I know, I know, it is not a good set-up at all for intake air temperature (and I can confirm that!!), but it is only a temporary set-up which allows easily to run the car with 3 MAFs and do their calibration. Second picture shows the laptop and my acquisition system recording the MAFs voltage and the output of the MAF combiner once I have updated the look-up tables. The PDA, connected to the motronic via a bluetooth interface, allows to record the mass air flow as interpreted by the motronic. Third picture is a comparison of the MAF voltage and the MAF combiner voltage while driving the car. I am quite pleased with the result. The car was running the same whatever it was connected to the MAF or to the output of the MAF combiner. BTW, during this calibration process I had some surprises : - our MAF is able to go well above 5V, so I had to modify the gain of the MAF combiner output stage in order to duplicate that - the 3 MAFs have exactly the same calibration curve which can be approximated quite accurately by a simple math law. That made the calibration much more easy and accurate. Next steps, will be to re-install the modified covers, to complete the harness (95% done and used during calibration) and to make an air pickup in one bellows to feed the idle regulator. Almost done ... and i will know finally if it improves her breathing ... Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Throttle body injection (looks semi-custom to me) plus nitrous. Even without nitrous, his car is probably breathing a whole lot better than stock. Now if it could just pass our smog checks... RIGHT!
Individual throttle bodies. Pap posted some of Andy's kissass engine here -> http://ferrarichat.com/forum/showpost.php?p=138620023&postcount=43
It's pretty hard to get a nice swig of milkshake when you're trying to suck it through a coffee straw.[/QUOTE] Yeah....That's what she said...
The Motronic has a bluetooth interface??!! What s/w was used on the PDA to interpret the signals/data? Sorry if I missed something in the thread about it. Thx! - Tim
No, obviously, the motronic itself doesn't have a bluetooth interface. But, you can buy cheap OBD bluetooth interfaces on ebay (search for : ELM327 + bluetooth) which can be connected to the OBD connector, and allows to communicate with a laptop or a PDA without any wire. For the software, I started with "microOBD" which is a freeware for PDA (http://www.geocities.com/a_ser_files/). Then, I tailored it for a correct operation with a bluetooth communication port, and to adapt it according to the data available on the F355. OBDgauge (http://www.qcontinuum.org/obdgauge/) is another practical freeware for PDA.
