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Hi all,
Thought I would share with you all my project to supercharge my 1991 MX-5 as it is now finished
Basically, the project was to build my own Megasquirt replacement/standalone ECU then build a kit based around the BMW mini cooper S M45 supercharger.
This has been pioneered by someone on one of the MX5 forums I visit, here is his build log:
http://www.mx5nutz.com/forum/index.php?showtopic=42329
Setup as it stands:
DIY Megasquirt 1 V3.0 standalone ECU (built this and had it running for 6 months NA - the only way to go IMO)
RX-8 425cc injectors (these are plug and play)
Eaton M45 supercharger with standard pulley
1.8 clutch and flywheel fitted
LC-1 WB O2 sensor with gauge in eyeball air vent
Front mounted intercooler
I'll just let the pictures do the talking........
This is the Megasquirt (MS1 V3.0) which took me many many hours to turn from a bare board into this. You build the basic kit with customisations to match specific engine configurations (to read sensors, control idle valve etc etc), luckily the B6 engine is a pretty simple engine.
This is the wiring loom connecting the MS to the stock wiring harness. The only modification to the stock harness was to disconnect the NB O2 sensor (I installed an LC-1 wideband with gauge) and to remove the AFM and connect up a GM IAT sensor in its place. The purple wire was disconnected as this was for the LC-1.
As this is such a big step (removing stock ECU and replacing with this) I decided to do this with the car still naturally aspirated and to run with it in this state for quite a while to iron out any problems and get my head around tuning it. I actually did a couple of track days like this, here is a video from one: http://www.youtube.com/watch?v=Cgxc_UIzEvk
and this is what the engine bay looked like at the time, the LC-1 wideband O2 sensor and gauge was fitted at this point too to help me tune the fuelling, for the spark map I defaulted to a basemap for this particular car and built some det cans to make sure the engine wasnt pinking. The exhaust manifold also had to be heat wrapped to create clearance for the supercharger.
I ran it like that for about 6 months whilst building the supercharger kit, the Eaton supercharger required a few modifications to be able to use it - the inlet had to be sawn off as did a bit near the pulley and tapped holes had to be made in the inlet for me to mount my inlet track (plus second throttle body) on.
These are some of the basic components, I managed to get someone at my previous place of work to do the welding for me for some beers which was handy
Yellow injectors are the RX-8 ones.
This is what it looked like when it all came together - note this was before I fitted the intercooler and havnt got any pictures of after it is fitted
http://img3.imageshack.us/img3/1187/dscf1348i.jpg
A little video of it idling:
http://www.youtube.com/watch?v=Jcks7vUuod4
I expect the engine is now producing somewhere in the region of 170-190BHP, others have had similar setups tuned on a rolling road with smaller supercharger pulley get 220BHP.
Looking forward to getting this on track
Thought I would share with you all my project to supercharge my 1991 MX-5 as it is now finished
Basically, the project was to build my own Megasquirt replacement/standalone ECU then build a kit based around the BMW mini cooper S M45 supercharger.
This has been pioneered by someone on one of the MX5 forums I visit, here is his build log:
http://www.mx5nutz.com/forum/index.php?showtopic=42329
Setup as it stands:
DIY Megasquirt 1 V3.0 standalone ECU (built this and had it running for 6 months NA - the only way to go IMO)
RX-8 425cc injectors (these are plug and play)
Eaton M45 supercharger with standard pulley
1.8 clutch and flywheel fitted
LC-1 WB O2 sensor with gauge in eyeball air vent
Front mounted intercooler
I'll just let the pictures do the talking........
This is the Megasquirt (MS1 V3.0) which took me many many hours to turn from a bare board into this. You build the basic kit with customisations to match specific engine configurations (to read sensors, control idle valve etc etc), luckily the B6 engine is a pretty simple engine.
This is the wiring loom connecting the MS to the stock wiring harness. The only modification to the stock harness was to disconnect the NB O2 sensor (I installed an LC-1 wideband with gauge) and to remove the AFM and connect up a GM IAT sensor in its place. The purple wire was disconnected as this was for the LC-1.
As this is such a big step (removing stock ECU and replacing with this) I decided to do this with the car still naturally aspirated and to run with it in this state for quite a while to iron out any problems and get my head around tuning it. I actually did a couple of track days like this, here is a video from one: http://www.youtube.com/watch?v=Cgxc_UIzEvk
and this is what the engine bay looked like at the time, the LC-1 wideband O2 sensor and gauge was fitted at this point too to help me tune the fuelling, for the spark map I defaulted to a basemap for this particular car and built some det cans to make sure the engine wasnt pinking. The exhaust manifold also had to be heat wrapped to create clearance for the supercharger.
I ran it like that for about 6 months whilst building the supercharger kit, the Eaton supercharger required a few modifications to be able to use it - the inlet had to be sawn off as did a bit near the pulley and tapped holes had to be made in the inlet for me to mount my inlet track (plus second throttle body) on.
These are some of the basic components, I managed to get someone at my previous place of work to do the welding for me for some beers which was handy
Yellow injectors are the RX-8 ones.
This is what it looked like when it all came together - note this was before I fitted the intercooler and havnt got any pictures of after it is fitted
http://img3.imageshack.us/img3/1187/dscf1348i.jpg
A little video of it idling:
http://www.youtube.com/watch?v=Jcks7vUuod4
I expect the engine is now producing somewhere in the region of 170-190BHP, others have had similar setups tuned on a rolling road with smaller supercharger pulley get 220BHP.
Looking forward to getting this on track
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