The Mid Night Club Wangan Run Touge Monster FD RX-7 RZ!
Discussion
Quick update:
Got my proper camera out, took a pic I'm really pleased with:
I need some kind of permanent mounting for the plate though.
I've been doing a bit of research and I now realise that my wheels, usually known as Mazdaspeed MS01s are actually much more rare than I realised previously, especially in the staggered setup that I have. I've never been completely content with the colour so at some point I'm interested in changing them to a dark bronze/gold - I might do a plasti-dip rather than paint first to see how it looks first.
I think the new fibreglass bumper is going to cause me more issues than I thought, I've noticed a few cracks here and there already and I've only used it for ~200 miles!
The slight increase in track with the new spacers has produced noticeable positive changes to handling. I took the car to one of my favourite local back roads and the thing feels so planted and the go-kart character has been enhanced to even more confidence inspiring levels.
I'm starting to get a bit annoyed by some of the more pronounced rattles and clunks inside the car so I might investigate the rear hatch as well as pillow ball bushes in the rear.
I still need to get around to fitting my new fuel rails, bigger injectors and mapping too.
I turned on my stereo the other day and now it has a very loud high pitched whine at all times. I traced this to the presence of the AFR gauge (the whine stops when I unplug it) so I will try adding a noise filter to the power wires and see if that fixes it.
That's all for now.
Got my proper camera out, took a pic I'm really pleased with:
I need some kind of permanent mounting for the plate though.I've been doing a bit of research and I now realise that my wheels, usually known as Mazdaspeed MS01s are actually much more rare than I realised previously, especially in the staggered setup that I have. I've never been completely content with the colour so at some point I'm interested in changing them to a dark bronze/gold - I might do a plasti-dip rather than paint first to see how it looks first.
I think the new fibreglass bumper is going to cause me more issues than I thought, I've noticed a few cracks here and there already and I've only used it for ~200 miles!
The slight increase in track with the new spacers has produced noticeable positive changes to handling. I took the car to one of my favourite local back roads and the thing feels so planted and the go-kart character has been enhanced to even more confidence inspiring levels.
I'm starting to get a bit annoyed by some of the more pronounced rattles and clunks inside the car so I might investigate the rear hatch as well as pillow ball bushes in the rear.
I still need to get around to fitting my new fuel rails, bigger injectors and mapping too.
I turned on my stereo the other day and now it has a very loud high pitched whine at all times. I traced this to the presence of the AFR gauge (the whine stops when I unplug it) so I will try adding a noise filter to the power wires and see if that fixes it.
That's all for now.
declasm said:
Quick update:
Got my proper camera out, took a pic I'm really pleased with:
I need some kind of permanent mounting for the plate though.
I've been doing a bit of research and I now realise that my wheels, usually known as Mazdaspeed MS01s are actually much more rare than I realised previously, especially in the staggered setup that I have. I've never been completely content with the colour so at some point I'm interested in changing them to a dark bronze/gold - I might do a plasti-dip rather than paint first to see how it looks first.
I think the new fibreglass bumper is going to cause me more issues than I thought, I've noticed a few cracks here and there already and I've only used it for ~200 miles!
The slight increase in track with the new spacers has produced noticeable positive changes to handling. I took the car to one of my favourite local back roads and the thing feels so planted and the go-kart character has been enhanced to even more confidence inspiring levels.
I'm starting to get a bit annoyed by some of the more pronounced rattles and clunks inside the car so I might investigate the rear hatch as well as pillow ball bushes in the rear.
I still need to get around to fitting my new fuel rails, bigger injectors and mapping too.
I turned on my stereo the other day and now it has a very loud high pitched whine at all times. I traced this to the presence of the AFR gauge (the whine stops when I unplug it) so I will try adding a noise filter to the power wires and see if that fixes it.
That's all for now.
Numberplate wise, I used to use a sticker on the front of my FD. There were at the time some companies on eBay that would print them. I don't believe they are strictly legal, but I never had an issue with the police or MOTs. Got my proper camera out, took a pic I'm really pleased with:
I need some kind of permanent mounting for the plate though.I've been doing a bit of research and I now realise that my wheels, usually known as Mazdaspeed MS01s are actually much more rare than I realised previously, especially in the staggered setup that I have. I've never been completely content with the colour so at some point I'm interested in changing them to a dark bronze/gold - I might do a plasti-dip rather than paint first to see how it looks first.
I think the new fibreglass bumper is going to cause me more issues than I thought, I've noticed a few cracks here and there already and I've only used it for ~200 miles!
The slight increase in track with the new spacers has produced noticeable positive changes to handling. I took the car to one of my favourite local back roads and the thing feels so planted and the go-kart character has been enhanced to even more confidence inspiring levels.
I'm starting to get a bit annoyed by some of the more pronounced rattles and clunks inside the car so I might investigate the rear hatch as well as pillow ball bushes in the rear.
I still need to get around to fitting my new fuel rails, bigger injectors and mapping too.
I turned on my stereo the other day and now it has a very loud high pitched whine at all times. I traced this to the presence of the AFR gauge (the whine stops when I unplug it) so I will try adding a noise filter to the power wires and see if that fixes it.
That's all for now.
About time for an update then!
I'm on the lookout for another C-West (or good copy) bumper since I don't think the one I have is ever going to be a great fit along where the bumper meets the bonnet and it always catches my eye now and annoys me, also the fibreglass had a small crack where the bumper meets the wing so I had to patch that up and it doesn't look great
The pic above is the (small) convoy I was part of on the way to the JDM Combe show a couple of weeks ago. The car on the left belongs to a guy named Curt (https://www.instagram.com/rocketracer7/) - it's a custom blended Rocket Bunny kit with an insane JDM GT wing on the back. The car on the right belongs to Jay (https://www.instagram.com/jrmotorworx/) and is actually an FD RX-7 too but this one has a full Rocket Bunny Pandem Boss kit in the style of the RX-3. Both of these cars got A LOT of attention at their first showing.
I'm starting to get serious about overhauling my fuel system, I decided I didn't want to mess around with the secondhand Bosch 1650cc EV-14 CNG injectors that I bought a while ago (£100 anyone?) so instead went ahead and ordered some Injector Dynamics ID1700's and a DM Motorsport secondary fuel rail and ACV blanking plates. I still need a few hoses and connectors and I'm yet to decide whether I'm going to replace my primaries with the secondhand 850cc injectors that I bought or splash out on a new set of more modern top feed injectors for the primaries too - decisions!
Once I have the whole fuel system decided I will fit it but I also want the option to do some of the ECU setup at home (setting injector sizes and timings) so I'm now on the lookout for an interface box for my Apexi Power FC ECU - either a Datalogit, FC Hako or Sonicrats box but they're all pretty hard to come by...
In other news I finally did a job I'd been putting off for a while...
My track rod ends had been wearing these attractive wraps! This stopped me from seeing what kind of condition they were in underneath. Thankfully once the wrap was off I could see that the boot and grease was all present and correct but I swapped them out anyway, and didn't re-wrap them! They were in tight though, necessitating the purchase of a ball joint splitter - my new favourite tool!
I love checking out these brakes when the wheels are off!
While the wheels were off I gave them a clean and also cleaned up my coilovers and springs a bit too.
Hopefully won't be long before the fuel system is all done and I can get this thing mapped to its true potential to try to get somewhere near 450-500bhp
I'm on the lookout for another C-West (or good copy) bumper since I don't think the one I have is ever going to be a great fit along where the bumper meets the bonnet and it always catches my eye now and annoys me, also the fibreglass had a small crack where the bumper meets the wing so I had to patch that up and it doesn't look great
The pic above is the (small) convoy I was part of on the way to the JDM Combe show a couple of weeks ago. The car on the left belongs to a guy named Curt (https://www.instagram.com/rocketracer7/) - it's a custom blended Rocket Bunny kit with an insane JDM GT wing on the back. The car on the right belongs to Jay (https://www.instagram.com/jrmotorworx/) and is actually an FD RX-7 too but this one has a full Rocket Bunny Pandem Boss kit in the style of the RX-3. Both of these cars got A LOT of attention at their first showing.
I'm starting to get serious about overhauling my fuel system, I decided I didn't want to mess around with the secondhand Bosch 1650cc EV-14 CNG injectors that I bought a while ago (£100 anyone?) so instead went ahead and ordered some Injector Dynamics ID1700's and a DM Motorsport secondary fuel rail and ACV blanking plates. I still need a few hoses and connectors and I'm yet to decide whether I'm going to replace my primaries with the secondhand 850cc injectors that I bought or splash out on a new set of more modern top feed injectors for the primaries too - decisions!
Once I have the whole fuel system decided I will fit it but I also want the option to do some of the ECU setup at home (setting injector sizes and timings) so I'm now on the lookout for an interface box for my Apexi Power FC ECU - either a Datalogit, FC Hako or Sonicrats box but they're all pretty hard to come by...
In other news I finally did a job I'd been putting off for a while...
My track rod ends had been wearing these attractive wraps! This stopped me from seeing what kind of condition they were in underneath. Thankfully once the wrap was off I could see that the boot and grease was all present and correct but I swapped them out anyway, and didn't re-wrap them! They were in tight though, necessitating the purchase of a ball joint splitter - my new favourite tool!
I love checking out these brakes when the wheels are off!
While the wheels were off I gave them a clean and also cleaned up my coilovers and springs a bit too.
Hopefully won't be long before the fuel system is all done and I can get this thing mapped to its true potential to try to get somewhere near 450-500bhp
Time for an update!
Went over to the August Haynes Breakfast Club in convoy with Jay's Pandem Boss Build _of course it broke down before we even left...) it was an awesome early morning run up on a clear morning. We met Simon with his super clean baby blue FD along the way too.
Jay decided to take pity on me and dump another old bumper on me to fix up as a swap for my poorly fitting one:
It had a few gnarly cracks in it but anything was going to fit better than the one I had
So same process as before - fibreglass repairs, filler, sanding, paintint, cutting and polishing....
..and eventually we get this:
Much better!
Did I ever demonstrate my LED headlight bulbs?
For a little while now I've had my APEXi Power FC Datalogit box / cable. This lets me plug a laptop into the ECU and monitor sensors and change settings and maps with much greater fidelity than you can from the hand commander. The idea is that I will eventually remap the fueling to accommodate my new Injector Dynamics ID1700 injectors. Now I will freely admit I'm not a great mechanic, not even a good one. I'm also terrible at body work, but before I get a backlash about how I'll blow myself and my car up if I try to map it myself let me present a counter argument: I have an A at A-Level Chemistry including extended modules on Stoichiometry and Gas Laws. I also have a degree in Theoretical Physics and 15 years as a computer programmer, I feel that adjusting a fuel map via a laptop is something that sits pretty squarely in the middle of my comfort zone.
First thing I did was rewire my fuel pump, adding in a relay to switch a brand new live using the old feed as a the switch voltage(I actually did it twice to be extra safe):
There's heaps of evidence around that old Mazda fuel pump wiring (and probably in other cars too) can cause significant voltage drops at the pump and hinder fuel pump and overall fuel system performance. My initial anecdotal experience after the wiring change is that boosting in 3rd and 4th is a whole AFR point richer than before (~10.5:1 at 9.5psi/0.68bar) and boosting in 2nd is overly rich now (<10:1). This is GREAT news it means that the rewire has done exactly what I'd hoped and is now supplying more voltage to the pump.
Before changing any injectors or changing anything else about the fuel system I want to get to know the current map a little better. Fortunately the FC-edit software built for the Power FC has some nifty logging features so I have therefore taken the car out and logged AFRs at different points in the map. This was averaged and normalised AFRs after about 30 mins of varied driving, boost on the Y axis (reversed) and RPM on the X.
This is the fuel map (previously tweaked by Ross at Dragon) the numbers are milliseconds of primary injector open time (although normalised from what actually happens which is primary injectors open then at a set % the secondaries open and pour in some more fuel at a different rate))
And here's that same map again but projected onto a line graph where lines are the fueling at different boost and the X is RPM (ignore the hole in bottom right - that area of the map isn't used for much - high RPM in vacuum
I'm going to spend more time logging AFRs and knock, then I'm going to swap my secondary injectors for the ID1700s, make sure they're setup and calibrated on the original map then incrementally adjust the wastegate duty to increase boost and adjusting fuel (while monitoring AFR and knock - retarding ignition anywhere in the map where knock seems more likely) up to about 16psi / 1.1bar (definitely not all at once!). I don't think I'd really like to map any higher than that without water/meth injection.
So that's the plan. Hopefully something I can get started on in the next couple of months.
Went over to the August Haynes Breakfast Club in convoy with Jay's Pandem Boss Build _of course it broke down before we even left...) it was an awesome early morning run up on a clear morning. We met Simon with his super clean baby blue FD along the way too.
Jay decided to take pity on me and dump another old bumper on me to fix up as a swap for my poorly fitting one:
It had a few gnarly cracks in it but anything was going to fit better than the one I had
So same process as before - fibreglass repairs, filler, sanding, paintint, cutting and polishing....
..and eventually we get this:
Much better!
Did I ever demonstrate my LED headlight bulbs?
For a little while now I've had my APEXi Power FC Datalogit box / cable. This lets me plug a laptop into the ECU and monitor sensors and change settings and maps with much greater fidelity than you can from the hand commander. The idea is that I will eventually remap the fueling to accommodate my new Injector Dynamics ID1700 injectors. Now I will freely admit I'm not a great mechanic, not even a good one. I'm also terrible at body work, but before I get a backlash about how I'll blow myself and my car up if I try to map it myself let me present a counter argument: I have an A at A-Level Chemistry including extended modules on Stoichiometry and Gas Laws. I also have a degree in Theoretical Physics and 15 years as a computer programmer, I feel that adjusting a fuel map via a laptop is something that sits pretty squarely in the middle of my comfort zone.
First thing I did was rewire my fuel pump, adding in a relay to switch a brand new live using the old feed as a the switch voltage(I actually did it twice to be extra safe):
There's heaps of evidence around that old Mazda fuel pump wiring (and probably in other cars too) can cause significant voltage drops at the pump and hinder fuel pump and overall fuel system performance. My initial anecdotal experience after the wiring change is that boosting in 3rd and 4th is a whole AFR point richer than before (~10.5:1 at 9.5psi/0.68bar) and boosting in 2nd is overly rich now (<10:1). This is GREAT news it means that the rewire has done exactly what I'd hoped and is now supplying more voltage to the pump.
Before changing any injectors or changing anything else about the fuel system I want to get to know the current map a little better. Fortunately the FC-edit software built for the Power FC has some nifty logging features so I have therefore taken the car out and logged AFRs at different points in the map. This was averaged and normalised AFRs after about 30 mins of varied driving, boost on the Y axis (reversed) and RPM on the X.
This is the fuel map (previously tweaked by Ross at Dragon) the numbers are milliseconds of primary injector open time (although normalised from what actually happens which is primary injectors open then at a set % the secondaries open and pour in some more fuel at a different rate))
And here's that same map again but projected onto a line graph where lines are the fueling at different boost and the X is RPM (ignore the hole in bottom right - that area of the map isn't used for much - high RPM in vacuum
I'm going to spend more time logging AFRs and knock, then I'm going to swap my secondary injectors for the ID1700s, make sure they're setup and calibrated on the original map then incrementally adjust the wastegate duty to increase boost and adjusting fuel (while monitoring AFR and knock - retarding ignition anywhere in the map where knock seems more likely) up to about 16psi / 1.1bar (definitely not all at once!). I don't think I'd really like to map any higher than that without water/meth injection.
So that's the plan. Hopefully something I can get started on in the next couple of months.
Time for a quick update. Unfortunately plans to install injectors and re-map have been delayed, car was basically blocked in the garage for 4 months while the kitchen was remodelled, once the weather sorts itself out (he says on a day where the sun is finally back out) I'll get on with it. I did get the car mot'd last week with zero surprises (only about 3500 miles since last year) so I'm good to drive for another year.
I bought the car a Christmas present - a new steering wheel! the old one was pretty tacky and cheap looking:
New wheel
Old wheel
New wheel fitted
Happy New Year all!
I bought the car a Christmas present - a new steering wheel! the old one was pretty tacky and cheap looking:
New wheel
Old wheel
New wheel fitted
Happy New Year all!
Things have been a bit quiet on this thread, winter and RX-7s don't mix that well so I've not really done too many miles of late with the exception of early March when I had to be in Farnborough for the best part of the week and my wife needed the X5 so I daily'd the RX- 7! Surrey and Hampshire have truly terrible pot-holed roads!
There has been one highlight in the past few months and that was a track day up in Wales at Llandow in February. I went up with a mate who was driving his 350z and we had a few laughs chasing each other around the track. The track let me stretch the car in a way that otherwise is inaccessible on the road and while also highlighting any weaknesses. I was blown away by the on-limit adjustability of this car on this suspension setup, it truly is like a go kart! The front-mid engine layout meant that the car just goes where you point it, not a sniff of understeer and the 2-way rear diff means that the rear end just dances as if the attitude of the car is directly wired to your brain as you brake and accelerate. Unfortunately the brakes aren't tip-top so as the fronts warmed up there was a lot of vibration through the steering so they're gonna need an overhaul and my other observation was that my race spec Quantum coilver setup although still hugely competent needs the at least the driver's front damper reconditioning. My mate and I also went out as passenger in each other's cars and the comparison was chalk and cheese! The 350z on track felt like a car whereas my RX-7 is an overpowering, visceral experience! The 350z definitely suffered from understeer too but then again my mate didn't disengage the driver aids so it may well be partly due to that.
Here's a little video of my over exuberance:
I hit a cone!
I also got a ride along with a mad Welshman driving a Ford Ka. that thing was hilarious and he drove it brilliantly - he managed to overtake a Corvette and an E46 M3!
A few pics of the day:
In other news I finally got round to fitting my upgraded injectors and fuel rails. A bit of steep learning curve for me since my car still had a bunch of vacuum hoses and solenoids left of from the original twin turbo setup but finally I got that all out of the way and tidied and got to my injectors. I've installed 850cc injectors as primaries and then my new Injector Dynamics 1700cc as secondaries. I plumbed it all in and pressure tested the system yesterday and so far so good, hopefully get the upper inlet manifold back on and have the car running this weekend and then I can spend some time on the map so I can finally up the boost. I'll start conservatively moving up to around 12psi and eventually work my way up to 16psi.
Here are a couple of nice pics I found of my car up at the last Haynes meet:
There has been one highlight in the past few months and that was a track day up in Wales at Llandow in February. I went up with a mate who was driving his 350z and we had a few laughs chasing each other around the track. The track let me stretch the car in a way that otherwise is inaccessible on the road and while also highlighting any weaknesses. I was blown away by the on-limit adjustability of this car on this suspension setup, it truly is like a go kart! The front-mid engine layout meant that the car just goes where you point it, not a sniff of understeer and the 2-way rear diff means that the rear end just dances as if the attitude of the car is directly wired to your brain as you brake and accelerate. Unfortunately the brakes aren't tip-top so as the fronts warmed up there was a lot of vibration through the steering so they're gonna need an overhaul and my other observation was that my race spec Quantum coilver setup although still hugely competent needs the at least the driver's front damper reconditioning. My mate and I also went out as passenger in each other's cars and the comparison was chalk and cheese! The 350z on track felt like a car whereas my RX-7 is an overpowering, visceral experience! The 350z definitely suffered from understeer too but then again my mate didn't disengage the driver aids so it may well be partly due to that.
Here's a little video of my over exuberance:
I hit a cone!
I also got a ride along with a mad Welshman driving a Ford Ka. that thing was hilarious and he drove it brilliantly - he managed to overtake a Corvette and an E46 M3!
A few pics of the day:
In other news I finally got round to fitting my upgraded injectors and fuel rails. A bit of steep learning curve for me since my car still had a bunch of vacuum hoses and solenoids left of from the original twin turbo setup but finally I got that all out of the way and tidied and got to my injectors. I've installed 850cc injectors as primaries and then my new Injector Dynamics 1700cc as secondaries. I plumbed it all in and pressure tested the system yesterday and so far so good, hopefully get the upper inlet manifold back on and have the car running this weekend and then I can spend some time on the map so I can finally up the boost. I'll start conservatively moving up to around 12psi and eventually work my way up to 16psi.
Here are a couple of nice pics I found of my car up at the last Haynes meet:
Quick update:
Injectors in, everything buttoned up. I cranked the car on the 850cc primary injector settings most people on rx7club.com seem to be using but it didn't want to catch. I went back to the original settings (set for 660cc on my car) and the car actually sprang to life and idled better than ever!? I've done a few tweaks and seem to have a solid idle but my AFRs are very rich at idle (11.5ish) so looking for other options. I can't wait to start doing some boosted pulls!
Injectors in, everything buttoned up. I cranked the car on the 850cc primary injector settings most people on rx7club.com seem to be using but it didn't want to catch. I went back to the original settings (set for 660cc on my car) and the car actually sprang to life and idled better than ever!? I've done a few tweaks and seem to have a solid idle but my AFRs are very rich at idle (11.5ish) so looking for other options. I can't wait to start doing some boosted pulls!
Nervousness, anxiety and jittery adrenaline feelings were my reward following the completion of the fuel system overhaul. I would have preferred some kind of relaxed satisfaction but to be honest relaxation is not a feeling readily associated with this car.
I realised that I had a work trip coming up which meant a long run from Exeter to Heathrow and with my wife needing the X5 for the next 3 days it had to be in the RX-7. So with a couple of days to go I needed to tie-up a few last jobs and do a shakedown and getting the mapping right.
After a bunch of back and forth (spending a lot of time on the rx7club forum reading old posts) I pretty much had the new injectors all configured in terms of size, lag, and their proportional flow compared to what my fuel map was expecting from the old injectors. I also had spent a long time in Excel smoothing out some kinks and inconsistencies in the map. Strangely though the car was harder to start than it used to be, cranking for 10-15 seconds (more on that later). I'd pressure tested the new fuel system up to 60psi (that's what it would see if I was running 20psi boost on top of base fuel pressure of 40psi) and had no leaks - in fact I had far less of a petrol smell now than i used to from under the bonnet!
So I went out very tentatively for a test drive/shakedown. I kept my laptop plugged in while I drove some local roads so that I could log all the things (manifold pressure, RPM, knock, injector duty, coolant temp, AFR etc.) My numbers looked good - well, all except water temp which the ecu was seeing as maxed out (an open circuit on the sensor). I even pushed into boost a couple of times and not only did my injectors not fly out of the rail but my new manifold blanking plates stayed firm too, did I mention I had to remove a bunch of redundant emissions crap to fit the secondary fuel rail?. After 40 mins of driving around and a few tweaks to the map here and there to fill in a bit of fuel, I was feeling a lot more confident. After a quick google I worked out where the wire for the coolant sensor was and it took about 10 seconds for me to spot the problem - somehow I had cleanly cut through the wires! Most likely while I was cutting some of the old vacuum hoses to access the injectors. Annoyingly the wire was in a very awkward place next to the inlet manifold so it was a fiddly 30 mins to get the cut wires stripped and joined back together. Now the car jumped into life after a short crank so obviously the sensor was the starting issue. The next day was the big one. I packed a huge bag of tools including the necessary zip ties and duck tape for my drive up to Heathrow. My flight was at 830 on Wednesday so my plan was to drive up to Woking on Tuesday night and do the last 20mins the next morning - at least then if the car did break on Tuesday I'd have a fighting chance of still making my flight! Thankfully nothing broke! Despite driving the length of the A303 and covering about 150 miles, the new fuel system and my own mapping got us through. I hit boost several times and adjusted the boost controller duty up slightly allowing me to see 0.89kg/cm2 which is 12.4psi.
Safely tucked away in Woking where I left it the night before!
Some max numbers on the ECU monitor
To be honest this new level of boost felt pretty scary! I'm going to have to get used to this car all over again! At this boost I was still seeing AFRs in the mid 10s and fuel duty only hitting low 60s so it would seem plenty of headroom for more as long as the fuel pump can keep up.
Arrived at Heathrow! Don't look too close it's covered in dirt and bugs!
So what next? I'm going to continue logging my ecu readings and afrs while driving around and keep tweaking the map until I'm happy and gradually up the boost to around the 16psi goal.
A prettier map
A sensor log
I'm also starting to get a bit sick and tired of the crashy race suspension and want something more streetable so looking at BC racing coilovers with 6/8kg springs.
I realised that I had a work trip coming up which meant a long run from Exeter to Heathrow and with my wife needing the X5 for the next 3 days it had to be in the RX-7. So with a couple of days to go I needed to tie-up a few last jobs and do a shakedown and getting the mapping right.
After a bunch of back and forth (spending a lot of time on the rx7club forum reading old posts) I pretty much had the new injectors all configured in terms of size, lag, and their proportional flow compared to what my fuel map was expecting from the old injectors. I also had spent a long time in Excel smoothing out some kinks and inconsistencies in the map. Strangely though the car was harder to start than it used to be, cranking for 10-15 seconds (more on that later). I'd pressure tested the new fuel system up to 60psi (that's what it would see if I was running 20psi boost on top of base fuel pressure of 40psi) and had no leaks - in fact I had far less of a petrol smell now than i used to from under the bonnet!
So I went out very tentatively for a test drive/shakedown. I kept my laptop plugged in while I drove some local roads so that I could log all the things (manifold pressure, RPM, knock, injector duty, coolant temp, AFR etc.) My numbers looked good - well, all except water temp which the ecu was seeing as maxed out (an open circuit on the sensor). I even pushed into boost a couple of times and not only did my injectors not fly out of the rail but my new manifold blanking plates stayed firm too, did I mention I had to remove a bunch of redundant emissions crap to fit the secondary fuel rail?. After 40 mins of driving around and a few tweaks to the map here and there to fill in a bit of fuel, I was feeling a lot more confident. After a quick google I worked out where the wire for the coolant sensor was and it took about 10 seconds for me to spot the problem - somehow I had cleanly cut through the wires! Most likely while I was cutting some of the old vacuum hoses to access the injectors. Annoyingly the wire was in a very awkward place next to the inlet manifold so it was a fiddly 30 mins to get the cut wires stripped and joined back together. Now the car jumped into life after a short crank so obviously the sensor was the starting issue. The next day was the big one. I packed a huge bag of tools including the necessary zip ties and duck tape for my drive up to Heathrow. My flight was at 830 on Wednesday so my plan was to drive up to Woking on Tuesday night and do the last 20mins the next morning - at least then if the car did break on Tuesday I'd have a fighting chance of still making my flight! Thankfully nothing broke! Despite driving the length of the A303 and covering about 150 miles, the new fuel system and my own mapping got us through. I hit boost several times and adjusted the boost controller duty up slightly allowing me to see 0.89kg/cm2 which is 12.4psi.
Safely tucked away in Woking where I left it the night before!
Some max numbers on the ECU monitor
To be honest this new level of boost felt pretty scary! I'm going to have to get used to this car all over again! At this boost I was still seeing AFRs in the mid 10s and fuel duty only hitting low 60s so it would seem plenty of headroom for more as long as the fuel pump can keep up.
Arrived at Heathrow! Don't look too close it's covered in dirt and bugs!
So what next? I'm going to continue logging my ecu readings and afrs while driving around and keep tweaking the map until I'm happy and gradually up the boost to around the 16psi goal.
A prettier map
A sensor log
I'm also starting to get a bit sick and tired of the crashy race suspension and want something more streetable so looking at BC racing coilovers with 6/8kg springs.
Update for anyone following, got back from Heathrow to Exeter in one shot, felt a lot more confident in the car so lots of boosting and exploring different revs and engine loads on the map and everything is always safely rich for a rotary so overall a successful 340 miles on my map following my own work on the fuel system. As a bonus the smell of fuel I used to get on boost is no longer there - I think my old o-rings must have been past it. One thing that needs a bit of tweaking is my boost controller settings, I need to find a better balance between target boost and controller solenoid duty since I was getting some boost fluctuations around max - nice problem to have now that I actually can up the boost! I really want to drive it more now - feels like a new car again!
H20DJY said:
Love this! I always wanted a RX-7, wish I had gone for it back in the day! Deffo still on the up value wise and a car thats aged beautifully.
Thanks! Get one while you still can! I've been contemplating buying a tuned/mapped 135i or 235i to replace it but on my drive the other day I saw so many newish quick BMWs to the point where they just seemed so disappointingly common and boring. I can't remember the last time I found another RX-7 in the wild while driving mine.
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