4-Rotor FC Build
06-26-14, 08:46 PM
#1651
Passion for Racing
Join Date: Aug 2010
Location: Crown Point, Indiana
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You started this post during my senior year of high school, and now after college and manufacturer training you FINALLY start it up. Why do you work so slow :P
Congrats man, now go have a beer for me!
Congrats man, now go have a beer for me!
06-30-14, 04:19 AM
#1652
Newbie
Join Date: Aug 2013
Location: nz
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hey john congrats on the start up its as awesome as we al knew it would be! have a question have you had some time to play with it yet tune etc how does it respond or like not having any intake runner with the slide hard up like that? also fuel delivery working a treat so close without a great chance to mix with air until in chamber..chears
07-07-14, 08:29 PM
#1655
Hi John,
a quick question about your seats, how much room do you have with a Helmet on when you're sitting in the car? I've been looking at the Sparco Sprint's for my FC. I'm about 6' and with a helmet on I want to get as low as I can in the car so my head doesn't touch the roof.
a quick question about your seats, how much room do you have with a Helmet on when you're sitting in the car? I've been looking at the Sparco Sprint's for my FC. I'm about 6' and with a helmet on I want to get as low as I can in the car so my head doesn't touch the roof.
07-08-14, 02:03 AM
#1656
Thanks for the beer though!
hey john congrats on the start up its as awesome as we al knew it would be! have a question have you had some time to play with it yet tune etc how does it respond or like not having any intake runner with the slide hard up like that? also fuel delivery working a treat so close without a great chance to mix with air until in chamber..chears
I don't expect any problems with the injectors so close to the rotor housing, the distance between the rotor housing and the injector isn't that much different than the oem primairy injectors. I wanted the injectors after the slide throttlebody, and that's fitted as close to the engine as possible for good engine response.
Hi John,
a quick question about your seats, how much room do you have with a Helmet on when you're sitting in the car? I've been looking at the Sparco Sprint's for my FC. I'm about 6' and with a helmet on I want to get as low as I can in the car so my head doesn't touch the roof.
a quick question about your seats, how much room do you have with a Helmet on when you're sitting in the car? I've been looking at the Sparco Sprint's for my FC. I'm about 6' and with a helmet on I want to get as low as I can in the car so my head doesn't touch the roof.
Depends on the rails and rollcage. I'm a little over 6' and with the sparco sprint fitted on top of the oem seat rails, and the rollcage fitted against the inner shell it was too close. I had to cut away the inner shell, and fit the rollcage further upwards, here is a picture of what I mean:
After this it was do-able. With the oem rails removed and the seats as close to the floor as possible it was perfectly fine.
I sold the sprint's and got some sparco corsa's though, had to make some mounts for them so I could bolt them to the floor, but now it's fine. They are a bit slim though, perfect for me, but not everyone fits well in them.
07-09-14, 02:18 AM
#1658
Yep, there isn't really a big difference in headroom between the corsa and the sprints. I think you can get away without cutting up the shell if you get some shallow mounts (Which you probably have to do anyway, since the FC's passenger's seat mount is wierd), but if your welding in a cage instead of bolting it in I would always do the extra effort of notching the shell and moving the tube outwards. I've also seen people cutting out the crossbeam underneath the seat so the seat can be lowered 1,5 - 2".
07-13-14, 02:46 PM
#1660
Update
Yep, you've read it right, finally a good old fashioned update!
I actually had no other cars to work on this weekend :-), so I went to tinker on the mazda!
The last time I worked on it I fired it up and made the youtube vid.
5 minutes after that I put it away and it hadn't been touched since, until yesterday that is.
The first thing I started with was the brakes, I hate working on brakes so I've been putting it off, but with the engine running I really needed to get working on them. The original stuff was all rusty, worn and bad. I didn't want to get a big brake kit or anything like that because #1, they don't fit under my 16" wheels anyway, and #2, in my opinion there is nothing wrong with the turbo brakes if they are in good condition. So I rebuild the calipers, rebuild the master cylinder, got new rotors and pads, some new braided brake lines, and got a roll of brakeline.
After a few hours it looked like this:
Almost done!
I got everything done at the front, and the calipers and discs are mounted in the rear, but I ran out of brakeline, so I still need to make the brakelines for the rear. Need to fix those, bleed everything, should be gold by then!
The next thing I started messing with was the pickup sensor for the ecu. I checked the timing with a strobe light the last time it was running, and the timing was way off (firing 20-30 deg after TDC), and I couldn't seem to get it right by modifying the base timing in the ecu. The strobe light would also jitter a bit when I touched the throttle and the ecu would show lossed sync errors. So, my first thought was there was something wrong with the triggerwheel, because I made than one myself, and it's a little bit different than normal wheels. I was ordering a triggerwheel for another project last week, so I went ahead and got one for the mazda aswell.
Here is a picture of the 2 wheels, you can see the one I had made before has been hollowed out, I think that might have been affecting the VR sensor's output
The new wheel needed some machining, I went ahead and made a hub that locks the triggerwheel in place when tightened, but allows me to manually modify the base timing. The ecu can do it aswell, but I think its easier to do it manually. I just set the trigger timing in the ecu to 90deg BTDC, which is ideal, and adjust the triggerwheel to suit.
Triggerwheel with the hub:
I mounted everything, had to modify the VR sensor position a little bit, but after that all was looking good! I also had to make a new TDC mark, because the old one was marked on the triggerwheel, which is now gone. See that clear line with red fluid inside? I removed the leading sparkplug of the #1 rotor housing, made an adapter and hooked up that clear line. Set the rotor near TDC, fill the line with premixing oil, loosened the trailing plug a little bit, and rotate the e-shaft back and forth to bleed the air out, tightened the trailing plug and then rotate the engine past TDC very slowly with something big (I use a 40" long ratchet). You should see the fluid rising in the tube untill TDC is reached, after TDC it starts dropping. I do this with almost every engine to check the TDC position because the stock mark can be off and getting the timing right is very very important!
After this I thought it was time to fire the engine up, and see if it works.
Here is a vid:
Random thought's and notes after running the engine for 30 minutes:
- Wooohoooo! This is frigging awesome!
- VR sensor seems to work OK now, after a few adjustments the timing is now spot on perfect and stable!
- Engine runs soo much better with the ignition set right, even when firing at TDC it's much better than last time. It's now at about 15 deg BTDC at idle, which seems ok, the throttle response is insane, even without proper mapping.
- There is a metallic ticking noise coming from the engine. At first I was worried it was something inside the engine, but I found the issue by pressing a screwdriver against my ear and listening to different parts of the engine. The ticking noise is coming from the slide throttle. I think the aluminium slide is rattling against the slide throttle housing, because the intake and exhaust pulses are acting upon it. The throttleplate has about 0.2mm's of play in the housing so it can move freely without binding, but this is causing it to rattle. You can actually hear it in the youtube vid. Need to fix this, maybe by placing o-rings between the slide and the housing or something like that
- The #1 and #4 rotors are producing much more vaccuum than the #2 and #3 rotors. I found this by removing the air filter and holding each runner closed with my hand. I think this is also a problem caused by the slide intake. There is a TPS sensor positioned between the #2 and #3 rotors, and I think it's causing air to be able to 'leak' between the 2 runners. When I'm holding runner #2 shut I can feel a little bit of vaccuum, but when I also hold #3 runner shut, the vaccuum in #2 also becomes stronger. I think this can cause different AFR ratio's between all the 4 different rotors which is bad mojo, so I need to solve this.
One solution I can think of is relocating the TPS sensor. Another more rigorous solution is to switch the slide throttle for butterfly valves. It will need some time to build, and butterfly valves aren't as cool as the slide valve, but it would solve both problems I'm having.
- I need to set it rich at idle for it to run ok, AFR is at 10.5 - 11, when leaning it out the AFR keeps on reading lean right up to the point where it's so lean the engine dies. The brapping (misfiring) is probably messing with the AFR reading.
It does smoke quite a bit, but doesn't smell like engine oil, smells like premixing oil and fuel. Probably because i'm using a 1:100 premix ratio and it's running pretty rich. Need to do some more testing with this later.
- Need to setup megasquirt to turn on the fans, the output already works, I just need to set it in the software. I forgot to turn them on and after a while the engine got up to 92 deg celcius. Turning on the fans cooled it right back to 78 deg
- The alternator is acting up! When starting the car up the battery voltage is about 14 volts, which is ok, with the fans turned on it's about 12.5 or so. But after a while the alternator gets very hot and the voltage drops, After 20 minutes of running the voltage dropped to 11 volts, and the alternator was too hot to touch. It's a small 50 amps unit from a suzuki alto, I think I need to fit a bigger one.
- Oil pressure is about 8 bars at idle with a cold engine. With the oil temp warmed up to 90 deg C the pressure is about 3 bars at idle. Seems a little on the high side, but ok.
So not all is well, but ah well, it's a custom build 4-rotor so there are going to be some issues getting it running right. Luckily I can solve it all. The bigger problem for me at the moment is the slide throttle. Not sure If I'm going to try to fix it, or if I'm going with butterfly valves.
Also need to finish the brakes, fix the gearbox leak and replace the gearbox and diff fluids. The guy at the local tech inspection station is bugging me to take the car over there, because he reckons there's no good reason why it can't be street legal, so I'm kindoff itching to finish it and take it over there. Would be nice if it passes, then I might register it, and use it to go grocery shopping or whatever
Yep, you've read it right, finally a good old fashioned update!
I actually had no other cars to work on this weekend :-), so I went to tinker on the mazda!
The last time I worked on it I fired it up and made the youtube vid.
5 minutes after that I put it away and it hadn't been touched since, until yesterday that is.
The first thing I started with was the brakes, I hate working on brakes so I've been putting it off, but with the engine running I really needed to get working on them. The original stuff was all rusty, worn and bad. I didn't want to get a big brake kit or anything like that because #1, they don't fit under my 16" wheels anyway, and #2, in my opinion there is nothing wrong with the turbo brakes if they are in good condition. So I rebuild the calipers, rebuild the master cylinder, got new rotors and pads, some new braided brake lines, and got a roll of brakeline.
After a few hours it looked like this:
Almost done!
I got everything done at the front, and the calipers and discs are mounted in the rear, but I ran out of brakeline, so I still need to make the brakelines for the rear. Need to fix those, bleed everything, should be gold by then!The next thing I started messing with was the pickup sensor for the ecu. I checked the timing with a strobe light the last time it was running, and the timing was way off (firing 20-30 deg after TDC), and I couldn't seem to get it right by modifying the base timing in the ecu. The strobe light would also jitter a bit when I touched the throttle and the ecu would show lossed sync errors. So, my first thought was there was something wrong with the triggerwheel, because I made than one myself, and it's a little bit different than normal wheels. I was ordering a triggerwheel for another project last week, so I went ahead and got one for the mazda aswell.
Here is a picture of the 2 wheels, you can see the one I had made before has been hollowed out, I think that might have been affecting the VR sensor's output
The new wheel needed some machining, I went ahead and made a hub that locks the triggerwheel in place when tightened, but allows me to manually modify the base timing. The ecu can do it aswell, but I think its easier to do it manually. I just set the trigger timing in the ecu to 90deg BTDC, which is ideal, and adjust the triggerwheel to suit.
Triggerwheel with the hub:
I mounted everything, had to modify the VR sensor position a little bit, but after that all was looking good! I also had to make a new TDC mark, because the old one was marked on the triggerwheel, which is now gone. See that clear line with red fluid inside? I removed the leading sparkplug of the #1 rotor housing, made an adapter and hooked up that clear line. Set the rotor near TDC, fill the line with premixing oil, loosened the trailing plug a little bit, and rotate the e-shaft back and forth to bleed the air out, tightened the trailing plug and then rotate the engine past TDC very slowly with something big (I use a 40" long ratchet). You should see the fluid rising in the tube untill TDC is reached, after TDC it starts dropping. I do this with almost every engine to check the TDC position because the stock mark can be off and getting the timing right is very very important!
After this I thought it was time to fire the engine up, and see if it works.
Here is a vid:
Random thought's and notes after running the engine for 30 minutes:
- Wooohoooo! This is frigging awesome!
- VR sensor seems to work OK now, after a few adjustments the timing is now spot on perfect and stable!
- Engine runs soo much better with the ignition set right, even when firing at TDC it's much better than last time. It's now at about 15 deg BTDC at idle, which seems ok, the throttle response is insane, even without proper mapping.
- There is a metallic ticking noise coming from the engine. At first I was worried it was something inside the engine, but I found the issue by pressing a screwdriver against my ear and listening to different parts of the engine. The ticking noise is coming from the slide throttle. I think the aluminium slide is rattling against the slide throttle housing, because the intake and exhaust pulses are acting upon it. The throttleplate has about 0.2mm's of play in the housing so it can move freely without binding, but this is causing it to rattle. You can actually hear it in the youtube vid. Need to fix this, maybe by placing o-rings between the slide and the housing or something like that
- The #1 and #4 rotors are producing much more vaccuum than the #2 and #3 rotors. I found this by removing the air filter and holding each runner closed with my hand. I think this is also a problem caused by the slide intake. There is a TPS sensor positioned between the #2 and #3 rotors, and I think it's causing air to be able to 'leak' between the 2 runners. When I'm holding runner #2 shut I can feel a little bit of vaccuum, but when I also hold #3 runner shut, the vaccuum in #2 also becomes stronger. I think this can cause different AFR ratio's between all the 4 different rotors which is bad mojo, so I need to solve this.
One solution I can think of is relocating the TPS sensor. Another more rigorous solution is to switch the slide throttle for butterfly valves. It will need some time to build, and butterfly valves aren't as cool as the slide valve, but it would solve both problems I'm having.
- I need to set it rich at idle for it to run ok, AFR is at 10.5 - 11, when leaning it out the AFR keeps on reading lean right up to the point where it's so lean the engine dies. The brapping (misfiring) is probably messing with the AFR reading.
It does smoke quite a bit, but doesn't smell like engine oil, smells like premixing oil and fuel. Probably because i'm using a 1:100 premix ratio and it's running pretty rich. Need to do some more testing with this later.
- Need to setup megasquirt to turn on the fans, the output already works, I just need to set it in the software. I forgot to turn them on and after a while the engine got up to 92 deg celcius. Turning on the fans cooled it right back to 78 deg
- The alternator is acting up! When starting the car up the battery voltage is about 14 volts, which is ok, with the fans turned on it's about 12.5 or so. But after a while the alternator gets very hot and the voltage drops, After 20 minutes of running the voltage dropped to 11 volts, and the alternator was too hot to touch. It's a small 50 amps unit from a suzuki alto, I think I need to fit a bigger one.
- Oil pressure is about 8 bars at idle with a cold engine. With the oil temp warmed up to 90 deg C the pressure is about 3 bars at idle. Seems a little on the high side, but ok.
So not all is well, but ah well, it's a custom build 4-rotor so there are going to be some issues getting it running right. Luckily I can solve it all. The bigger problem for me at the moment is the slide throttle. Not sure If I'm going to try to fix it, or if I'm going with butterfly valves.
Also need to finish the brakes, fix the gearbox leak and replace the gearbox and diff fluids. The guy at the local tech inspection station is bugging me to take the car over there, because he reckons there's no good reason why it can't be street legal, so I'm kindoff itching to finish it and take it over there. Would be nice if it passes, then I might register it, and use it to go grocery shopping or whatever
07-13-14, 03:57 PM
#1663
Red Pill Dealer
iTrader: (10)
Haha! As always, it's in the details. Awesome work man!
07-13-14, 06:19 PM
#1664
Moderator
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Update
- I need to set it rich at idle for it to run ok, AFR is at 10.5 - 11, when leaning it out the AFR keeps on reading lean right up to the point where it's so lean the engine dies. The brapping (misfiring) is probably messing with the AFR reading.
It does smoke quite a bit, but doesn't smell like engine oil, smells like premixing oil and fuel. Probably because i'm using a 1:100 premix ratio and it's running pretty rich. Need to do some more testing with this later.
- I need to set it rich at idle for it to run ok, AFR is at 10.5 - 11, when leaning it out the AFR keeps on reading lean right up to the point where it's so lean the engine dies. The brapping (misfiring) is probably messing with the AFR reading.
It does smoke quite a bit, but doesn't smell like engine oil, smells like premixing oil and fuel. Probably because i'm using a 1:100 premix ratio and it's running pretty rich. Need to do some more testing with this later.
extra oil can't be bad during the break in
07-14-14, 08:00 PM
#1665
Senior Member
I can't get enough of this build!! EPIC. Have you ever thought about roller barrel throttles? Not as slim & sexy as your slide throttle, but could possibly get better sealing between ports w/just simple o-rings....
07-15-14, 01:24 AM
#1667
Exhaust Manifold Leak
seems to idle really well even with the #2 and 3 running leaner because of the air leak. I think for a streetcar it could be an issue but for a track only car it should not make such much a difference. you could also introduce an airleak in #1 and 4 to balance them out during idle.
just a quick tought I had about the drive ratio of ther water pump. I have been told these pump start to cavitate around 5600 pump rpm. this is probabely a bit a on the low side but I would maybe have a 2nd look of this especially on a 4 rotor.
on our 2 rotor 13B PP we are running the pump now at 56% of the crank speed.
just a quick tought I had about the drive ratio of ther water pump. I have been told these pump start to cavitate around 5600 pump rpm. this is probabely a bit a on the low side but I would maybe have a 2nd look of this especially on a 4 rotor.
on our 2 rotor 13B PP we are running the pump now at 56% of the crank speed.
07-15-14, 10:50 AM
#1669
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seems to idle really well even with the #2 and 3 running leaner because of the air leak. I think for a streetcar it could be an issue but for a track only car it should not make such much a difference. you could also introduce an airleak in #1 and 4 to balance them out during idle..
also you should keep the noise the throttle makes, normal throttle are quiet and boring....
07-15-14, 04:33 PM
#1670
seems to idle really well even with the #2 and 3 running leaner because of the air leak. I think for a streetcar it could be an issue but for a track only car it should not make such much a difference. you could also introduce an airleak in #1 and 4 to balance them out during idle.
just a quick tought I had about the drive ratio of ther water pump. I have been told these pump start to cavitate around 5600 pump rpm. this is probabely a bit a on the low side but I would maybe have a 2nd look of this especially on a 4 rotor.
on our 2 rotor 13B PP we are running the pump now at 56% of the crank speed.
just a quick tought I had about the drive ratio of ther water pump. I have been told these pump start to cavitate around 5600 pump rpm. this is probabely a bit a on the low side but I would maybe have a 2nd look of this especially on a 4 rotor.
on our 2 rotor 13B PP we are running the pump now at 56% of the crank speed.
Mmm yeah well it's not really leaking to the outside world, the problem is that the #2 and #3 runners are somewhat connected, like there is a small tube between the 2. I'll hook up vaccuum gauges to each individual rotor housing so I can see what's what.
Wow, your waterpump is running really slow! Mine is a little less underdriven, I believe it turns 15% slower than stock like the racingbeat pully set does.
I didn't want the waterpump to turn too slow because that makes the water flow very slow when the engine idles, normally not a huge issue, but since my engine is so long I was afraid that the rear part of the engine would get very very hot.
Also my engine doesn't make the same rpm as your engine does, 8500 rpm max, which isn't that much higher than stock.
hmm good point. my dads friend owns this Porsche 911 race car, and they were warming it up so he could go ****** around, and the mechanic had me put my hand behind each exhaust pipe, there is 1 per bank, and at idle one bank was idling perfect, and the other was basically not running at all, i guess with slide throttle you pick where it is running best, and since its a track car, they picked WOT.
also you should keep the noise the throttle makes, normal throttle are quiet and boring....
also you should keep the noise the throttle makes, normal throttle are quiet and boring....
Wow, that porsche is cool!
I'm not that worried about the idle, but I wonder if it has an effect at lower loads. I'm sure it's fine at full throttle. Not that thrilled about the noise though, It's not an awesome mechanical noise like the whining of straight gears or the spooling of a turbo, it just a rattling noise, like a diesel that hasn't warmed up yet.
07-15-14, 06:14 PM
#1671
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it is, its got a factory cage, the MFI setup, all the engine tin is fiberglass, turbo flares, all factory.
cool cars usually make weird noises... the thing Ferrari does so well is to get all the noises to come together at WOT and sound good
I'm not that worried about the idle, but I wonder if it has an effect at lower loads. I'm sure it's fine at full throttle. Not that thrilled about the noise though, It's not an awesome mechanical noise like the whining of straight gears or the spooling of a turbo, it just a rattling noise, like a diesel that hasn't warmed up yet.
07-17-14, 10:23 AM
#1674
With a slide throttle like that, I'm not surprised that the inner two rotors aren't pulling as much vacuum - regardless of the TPS sensor, there are leakage paths alongside the slide plate from other rotors on both sides of rotors 2 & 3, whereas rotors 1 & 4 only have one of those leakage paths. Maybe o-rings around the runners on the engine-side of the slide plate, or at least teflon bars between runners on the engine-side to help support the slide & seal off the gap? I'd be worried about the slide possibly grabbing the o-ring when closing & moving it out of position or damaging it.
At idle, especially if the inner two rotors are running significantly leaner, the AFR overall will read rich since you will need to add enough fuel to those middle rotors to get them slightly rich (say 12.5 or 13:1), and then the outer rotors will be down at 10:1 or so since they're pulling more vacuum. Fix the vacuum distribution problem, and I'm sure you'll be able to lean out the idle AFRs a bit.
It's sounding great when idling & revving though, I bet it feels even better to have gotten to this point!
At idle, especially if the inner two rotors are running significantly leaner, the AFR overall will read rich since you will need to add enough fuel to those middle rotors to get them slightly rich (say 12.5 or 13:1), and then the outer rotors will be down at 10:1 or so since they're pulling more vacuum. Fix the vacuum distribution problem, and I'm sure you'll be able to lean out the idle AFRs a bit.
It's sounding great when idling & revving though, I bet it feels even better to have gotten to this point!
07-17-14, 11:45 AM
#1675
Red Pill Dealer
iTrader: (10)
Originally Posted by John Huijben
- There is a metallic ticking noise coming from the engine. At first I was worried it was something inside the engine, but I found the issue by pressing a screwdriver against my ear and listening to different parts of the engine. The ticking noise is coming from the slide throttle. I think the aluminium slide is rattling against the slide throttle housing, because the intake and exhaust pulses are acting upon it. The throttleplate has about 0.2mm's of play in the housing so it can move freely without binding, but this is causing it to rattle. You can actually hear it in the youtube vid. Need to fix this, maybe by placing o-rings between the slide and the housing or something like that