4-Rotor FC Build
08-22-14, 11:52 AM
#1754
MegaSquirt Mod
That will also probably do just fine, but you can't really get oil in the engine's main and rotor bearings, and I have all the stuff I need to pressure fill it lying around the shop, so it doesn't really take a big effort.
The center of it is a microsquirt 2.2 module, but I designed and assembled the breakout board to which the module mounts myself, which adds a few ignition and injection channels (so it does sequential injection), it also adds a few general outputs and bluetooth connectivity. I fitted everything in a small waterproof industrial enclousure.
I tested it in the car tonight and everything works!
, all sensors are showing up nicely, outputs are working, all injectors are working, sparks are working so I'm happy 
I did hit one snag though, the #2 trailing plug isn't sparking as strong as all the other plugs. The problem seems to be the external bosch igniter box. One of the channels does seem to be switching, but it's not completely switching to ground, when it switches there's still a resistance, so the coil doesn't charge so well. Kind of bummed, because apart from that it's really almost ready for it's first start!
Yep, your right, these are hydraulic lines and fittings. The lines are -10an size, but they run in parallel. (the front iron is tapped, so there are 2 oil lines coming out of the engine) so combined the flow area is quite large. The fittings are indeed a lot thicker, I bored the fittings out on the lathe to make them thinner and flow more.
The center of it is a microsquirt 2.2 module, but I designed and assembled the breakout board to which the module mounts myself, which adds a few ignition and injection channels (so it does sequential injection), it also adds a few general outputs and bluetooth connectivity. I fitted everything in a small waterproof industrial enclousure.
I tested it in the car tonight and everything works!
, all sensors are showing up nicely, outputs are working, all injectors are working, sparks are working so I'm happy I did hit one snag though, the #2 trailing plug isn't sparking as strong as all the other plugs. The problem seems to be the external bosch igniter box. One of the channels does seem to be switching, but it's not completely switching to ground, when it switches there's still a resistance, so the coil doesn't charge so well. Kind of bummed, because apart from that it's really almost ready for it's first start!Yep, your right, these are hydraulic lines and fittings. The lines are -10an size, but they run in parallel. (the front iron is tapped, so there are 2 oil lines coming out of the engine) so combined the flow area is quite large. The fittings are indeed a lot thicker, I bored the fittings out on the lathe to make them thinner and flow more.
I know I'm resurrecting and old post, but....
Darn, I was hoping that you'd go with MS3. I wanted to see full sequential staged injection and leading and trailing split code on an engine. James and I worked hard to get that code solid.
Ken
08-23-14, 08:32 AM
#1755
Yeah, I can understand that. I would go MS3 if I had to chose an ecu again and I'm actually thinking about upgrading during the coming winter. Not sure If I'm going to use staged injection and split timing though, I don't really see the need for either because the engine isn't turbocharged, but I would like more IO and datalogging which is why I'm thinking of changing.
I disassembled a few engines and measured everything out. The locations of the tension bolts and that sort of stuff is measured on an X-Y table so it's accurate. The trochoid shape is calculated, and the overal shape of the rotor housing is done by placing it over a piece of paper, tracing the edges, scanning the result, and converting it to solidworks.
Last week very little has been done to the 4-rotor because I've been on vacation, but I have sourced a larger alternator since the small 50amp one I currently have is unable to keep a steady voltage and gets very hot. It's a 100amp bosch one, but it's a bit larger than the current one, so I'll probably need to mount it a bit more to the side. Will be continued
Last week very little has been done to the 4-rotor because I've been on vacation, but I have sourced a larger alternator since the small 50amp one I currently have is unable to keep a steady voltage and gets very hot. It's a 100amp bosch one, but it's a bit larger than the current one, so I'll probably need to mount it a bit more to the side. Will be continued
08-25-14, 12:02 AM
#1756
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Originally Posted by John Huijben;
I have sourced a larger alternator since the small 50amp one I currently have is unable to keep a steady voltage and gets very hot. It's a 100amp bosch one, but it's a bit larger than the current one, so I'll probably need to mount it a bit more to the side. Will be continued
08-25-14, 05:56 AM
#1757
Nah, that won't work, I can't mount the alternator in the stock position because it will interfere with my hood and the intake, the small alto alternator could be mounted about where the power steering usually is, but anything bigger needs to be side mounted. Also not using the oem pullys and belt, Im using lightweight aluminium pullys and a v-belt
08-26-14, 04:06 PM
#1758
MegaSquirt Mod
Yeah, I can understand that. I would go MS3 if I had to chose an ecu again and I'm actually thinking about upgrading during the coming winter. Not sure If I'm going to use staged injection and split timing though, I don't really see the need for either because the engine isn't turbocharged, but I would like more IO and datalogging which is why I'm thinking of changing.
MS3 doesn't necessarily just stage on RPM or even just 2 conditions, you can specify the staging strategy in a table, where 0% means don't stage, and 100% means split PW between primaries and secondaries. This gives you really fine control over the staging and allows you to run small primaries for good low-load tuning, and then once you start getting into the throttle a little, you can start partially staging to keep the duties down. But you can stage smoothly and progressively through the table as you see fit and it's basically seamless. You can't tell when it stages tuned this way without looking at the datalogs.
How are you running ignition on the leading and trailing? I saw that you were controlling both from the primary signal somehow, but are you trying to run a dual post coil for each rotor (bad) or running COP and somehow driving the 2 coils off of one signal?
Split timing on an NA engine can still have some benefits for responsiveness and fuel economy if you run negative split, though IIRC you are running peripheral ports (correct me if I am remembering wrong) and I don't know how it would interact with that setup.
Ken
08-26-14, 05:55 PM
#1759
Yes, I'm familiar with the table based staging, I've actually used it on my FD using an MS2, works very well indeed. I don't think my problems at lower loads are being caused by inaccurate fuel metering, I'm using 4 ID1000 injectors, pulsewidth at idle is about 3ms, seems ok to me.
I am using 8 independent coils, the coils look like dual tower ones, but they are 2 coils in one housing, here is the datasheet:
http://www.bosch-motorsport.de/media...8159755pdf.pdf
I am using 2 external 4-channel bosch igniter boxes, so I have 8 igniters. Each microsquirt ignition channel is wired to 2 igniters, I added 100ohm pullup resistors for channel 3 and 4.
Spark seems to be pretty good using 3ms of dwell.
I don't think I'll ever run negative split, I know the RX-8 does it, and that it helps with economy, but I don't have any experience with it myself, and I don't want to try it out on a 4-rotor, the slight (if any) gains possible are not worth it to me. I guess if I could do split timing I would run 10 degrees everywhere to gain some safety margin but on the other hand, I kindoff like having the leading and trailing coils tied together because it makes it impossible to screw the split timing up.
I am using 8 independent coils, the coils look like dual tower ones, but they are 2 coils in one housing, here is the datasheet:
http://www.bosch-motorsport.de/media...8159755pdf.pdf
I am using 2 external 4-channel bosch igniter boxes, so I have 8 igniters. Each microsquirt ignition channel is wired to 2 igniters, I added 100ohm pullup resistors for channel 3 and 4.
Spark seems to be pretty good using 3ms of dwell.
I don't think I'll ever run negative split, I know the RX-8 does it, and that it helps with economy, but I don't have any experience with it myself, and I don't want to try it out on a 4-rotor, the slight (if any) gains possible are not worth it to me. I guess if I could do split timing I would run 10 degrees everywhere to gain some safety margin but on the other hand, I kindoff like having the leading and trailing coils tied together because it makes it impossible to screw the split timing up.
08-27-14, 06:02 AM
#1765
Nah that's not it,
No worries, the engine is running fine. I have a leak coming from the oilpan, and a leak coming from the front cover. I also want to fit the new alternator.
All of this stuff can be done with the engine in the car, but its not that much work to pull the engine, took me about 2 hours.
With the engine out of the car I also want to pull the transmission, intake and exhaust, just making sure if all the parts are ok and if nothing is abnormally worn or anything.
On a side note, struggling with the crappy oil pan makes me want to go dry sump, anyone ever tried using the stock oilpump as a suction pump, and then adding an external one for pressure?
No worries, the engine is running fine. I have a leak coming from the oilpan, and a leak coming from the front cover. I also want to fit the new alternator.
All of this stuff can be done with the engine in the car, but its not that much work to pull the engine, took me about 2 hours.
With the engine out of the car I also want to pull the transmission, intake and exhaust, just making sure if all the parts are ok and if nothing is abnormally worn or anything.
On a side note, struggling with the crappy oil pan makes me want to go dry sump, anyone ever tried using the stock oilpump as a suction pump, and then adding an external one for pressure?
08-27-14, 08:07 AM
#1768
Exhaust Manifold Leak
I can recommand the auto verdi hardware, we're running this pump on our RX3 track car. I think a 3 stage pump with centrifugal air/oil separator is about 1600 euro new. the quality of the hardware is really nice and the customer service and communication is really good.
08-27-14, 12:10 PM
#1770
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Spark seems to be pretty good using 3ms of dwell.
I don't think I'll ever run negative split, I know the RX-8 does it, and that it helps with economy, but I don't have any experience with it myself, and I don't want to try it out on a 4-rotor, the slight (if any) gains possible are not worth it to me. I guess if I could do split timing I would run 10 degrees everywhere to gain some safety margin but on the other hand, I kindoff like having the leading and trailing coils tied together because it makes it impossible to screw the split timing up.
I don't think I'll ever run negative split, I know the RX-8 does it, and that it helps with economy, but I don't have any experience with it myself, and I don't want to try it out on a 4-rotor, the slight (if any) gains possible are not worth it to me. I guess if I could do split timing I would run 10 degrees everywhere to gain some safety margin but on the other hand, I kindoff like having the leading and trailing coils tied together because it makes it impossible to screw the split timing up.
that being said, my MSD blew up, so i switched back to stock ignition, and so now i have 10 degrees of split, and it got even tamer. small matter i suppose.
and you could run negative split at idle, but having the brap brap idle is the cool part!
08-30-14, 09:01 PM
#1773
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Question: How heavy is your flywheel? Do you think you would benefit from a heavier one for street driving? I know you built this mainly for the track, but for informational purposes.
Jose
Jose
08-30-14, 10:27 PM
#1774
Rotary Enthusiast
I think I've run 4 different weight flywheels and they really make F#ck all difference. The clutch type on the other hand it huge (on my 5th clutch type)
08-31-14, 03:35 PM
#1775
The flywheel is very lightweight, it's just a thin ring gear with a small diameter clutch, so very low intertia:
However, a heavier one is not needed for the street. Now that it's tuned a bit better there are no driveability issues whatsoever. It drives quite nicely and smooth. Driving away from a standstill is super easy, it's actually more difficult to stall than my stock RX-8. Fuel economy isn't even that bad either as long as your moving. The problem is that it keeps on using a lot of fuel at idle which kills mileage.
However, a heavier one is not needed for the street. Now that it's tuned a bit better there are no driveability issues whatsoever. It drives quite nicely and smooth. Driving away from a standstill is super easy, it's actually more difficult to stall than my stock RX-8. Fuel economy isn't even that bad either as long as your moving. The problem is that it keeps on using a lot of fuel at idle which kills mileage.