4-Rotor FC Build
07-17-14, 11:47 AM
#1676
Red Pill Dealer
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For some reason the forum double posted my post.
Last edited by TonyD89; 07-17-14 at 11:49 AM.
07-17-14, 05:02 PM
#1678
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!
However, I did some testing tonight, and got some results!
First I measured the intake vaccuum of every rotor independently.
Every rotor pulls about 0.45 bars of vacuum at idle. Not really sure if that's a good number or not?, never had a PP engine before so not sure. At least everything measured equal
, My FD pulled about 0.65-0.7 bars at idle, but that was stock port so apples and oranges.I also measured vaccuum at 2000 and 3000 rpm, all rotors again tested equal.
Then I measured the AFR ratio at each rotor, which also showed everything being equal, AFR ratio shows about 1:11 at idle.
So, that all looks pretty good! I think I'm just going to run with it, and do some more testing with measuring individual rotors when it's actually driving.
Currently fixing some small random leaks and doing small things. Hope to be able to drive it around next week or so!
I'm with topless. I don't like the idea of o-rings because they could, maybe, come out. I think Teflon rings with a square cross section would be better. Actually, you could tighten up the clearance on the slide throttle a bit. I think .008" is a lot of clearance (don't hate me for the conversion but I have to think in what I know). .004 should be plenty don't you think?
07-19-14, 12:35 PM
#1679
So, I've been busy today, list of things I've done:
- Removed all 4 hubs an pressed in some extended wheel studs, 2,5" in the front, 2" in the rear
- Machined some 10mm thick hubcentric wheel spacers from 7075 alloy, needed these in the front because the 16" wheels were hitting the brake caliper
- Filled and bled the clutch (3 plate clutch is awesome, pedal effort is reasonable, and it's not grabby at all)
- Filled and bled the brake system, so it brakes now.
- Mounted the handbrake
- Filled the transmission and differential
- Mounted the shift lever and such.
So with the car now having 4 wheels, a working clutch, transmission, diff and working brakes I figured the car should be able to move and drive. So full of hope I hopped in the car and fired it up (scaring the hell out of everyone else in the workshop, firing it up makes some noise!). With a little effort I got it to move outside, and I drove a little bit, but the fuel map is way off. I tried leaning it at idle earlier this week, but now it stalls very easily when you try to drive it. at part throttle it seems like it runs way way too rich, it almost dies.
Here is the fuelmap I've got in there right now, VE at idle is about 23, but I think that needs to be in the 35 region for the engine to be happy, and I think the part and full throttle regions are way too rich. I'll do some testing with it later.
So basically it just needs tuning now, and a few minor things here and there if I want to try and get it street legal (Don't have any windscreen wipers yet, and forgot to mount a horn).
- Removed all 4 hubs an pressed in some extended wheel studs, 2,5" in the front, 2" in the rear
- Machined some 10mm thick hubcentric wheel spacers from 7075 alloy, needed these in the front because the 16" wheels were hitting the brake caliper
- Filled and bled the clutch (3 plate clutch is awesome, pedal effort is reasonable, and it's not grabby at all)
- Filled and bled the brake system, so it brakes now.
- Mounted the handbrake
- Filled the transmission and differential
- Mounted the shift lever and such.
So with the car now having 4 wheels, a working clutch, transmission, diff and working brakes I figured the car should be able to move and drive. So full of hope I hopped in the car and fired it up (scaring the hell out of everyone else in the workshop, firing it up makes some noise!). With a little effort I got it to move outside, and I drove a little bit, but the fuel map is way off. I tried leaning it at idle earlier this week, but now it stalls very easily when you try to drive it. at part throttle it seems like it runs way way too rich, it almost dies.
Here is the fuelmap I've got in there right now, VE at idle is about 23, but I think that needs to be in the 35 region for the engine to be happy, and I think the part and full throttle regions are way too rich. I'll do some testing with it later.
So basically it just needs tuning now, and a few minor things here and there if I want to try and get it street legal (Don't have any windscreen wipers yet, and forgot to mount a horn).
07-19-14, 09:38 PM
#1680
Red Pill Dealer
iTrader: (10)
(Don't have any windscreen wipers yet, and forgot to mount a horn).
07-21-14, 04:09 PM
#1684
With a little effort I got it to move outside, and I drove a little bit, but the fuel map is way off. I tried leaning it at idle earlier this week, but now it stalls very easily when you try to drive it. at part throttle it seems like it runs way way too rich, it almost dies.
Here is the fuelmap I've got in there right now, VE at idle is about 23, but I think that needs to be in the 35 region for the engine to be happy, and I think the part and full throttle regions are way too rich. I'll do some testing with it later.
Here is the fuelmap I've got in there right now, VE at idle is about 23, but I think that needs to be in the 35 region for the engine to be happy, and I think the part and full throttle regions are way too rich. I'll do some testing with it later.
07-21-14, 08:16 PM
#1685
Senior Member
So John, has Mazda offered you a job to assist in future rotary engine development?
07-23-14, 05:47 PM
#1686
Those actually work , I kept most of the stock stuff working, like the logicon/heater unit, the electric mirrors and windows, rear windscreen heater, ect. Just finished the windscreen wipers, almost done with the horn.
Nah that's not it. A car will usually drive when the accel enrichments are off, it will just stumble a bit when you get on the gas. I found the issue by the way, I messed up the scaling in the VE table, the first row was still at 30
(which is fine when using speed density, but I'm using alpha n, so the table should start at 0). It's running pretty well at the moment! , which is awesome because now I won't have to push the car in and out of the workshop anymore whenever I want to work on it . Idles a bit nicer and starts better aswell, maybe the engine has build some compression or something 
, still braps a bit at idle, and I don't think I'll ever be able to make it idle like stock, but it's not that bad, and once I start driving and loading the engine a bit the brapping goes away instantly.
, I kept most of the stock stuff working, like the logicon/heater unit, the electric mirrors and windows, rear windscreen heater, ect. Just finished the windscreen wipers, almost done with the horn. Nah that's not it. A car will usually drive when the accel enrichments are off, it will just stumble a bit when you get on the gas. I found the issue by the way, I messed up the scaling in the VE table, the first row was still at 30
(which is fine when using speed density, but I'm using alpha n, so the table should start at 0). It's running pretty well at the moment! , which is awesome because now I won't have to push the car in and out of the workshop anymore whenever I want to work on it . Idles a bit nicer and starts better aswell, maybe the engine has build some compression or something , still braps a bit at idle, and I don't think I'll ever be able to make it idle like stock, but it's not that bad, and once I start driving and loading the engine a bit the brapping goes away instantly.
07-23-14, 06:00 PM
#1687
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07-29-14, 01:36 AM
#1691
Well yeah it is pretty awesome, even at idle :-)
Spend some more time doing stuff like the windscreen jets, speedometer, mounting a horn, get the backup lights working (which was not fun at all), and I also made some screw in db-killers for the mufflers.
Yesterday I went to tech inspection with the car. It failed, in a nutshell because of this:
- It failed emissions, CO was 6.5%, when 4.5% is allowed. It's still running pretty rich though, I can probably lean it out a bit which should solve it.
- I'm running an catch can which is vented to the atmosphere, which is a no-no. Needs to be routed to the intake with a PCV valve
- The light-switch crapped out, the high-beam works when I pull the lever, but it won't stay on, as soon as I release the lever it goes out again
And a few minor things. The major issue though is noise and just the way it idles and runs. Not so much for the tech inspection because they don't have to check for db-level, but when I'm going to run it around like this I'm going to get pulled over a LOT. So need to figure out how to reduce the sound level a bit. If it was just loud at high rpms and higher loads then it wouldn't be such a huge issue, but it's loud at idle and low loads aswell. I started it up without mufflers for giggles and oh my god!! I didn't know an engine could be so loud!!
Spend some more time doing stuff like the windscreen jets, speedometer, mounting a horn, get the backup lights working (which was not fun at all), and I also made some screw in db-killers for the mufflers.
Yesterday I went to tech inspection with the car. It failed, in a nutshell because of this:
- It failed emissions, CO was 6.5%, when 4.5% is allowed. It's still running pretty rich though, I can probably lean it out a bit which should solve it.
- I'm running an catch can which is vented to the atmosphere, which is a no-no. Needs to be routed to the intake with a PCV valve
- The light-switch crapped out, the high-beam works when I pull the lever, but it won't stay on, as soon as I release the lever it goes out again
And a few minor things. The major issue though is noise and just the way it idles and runs. Not so much for the tech inspection because they don't have to check for db-level, but when I'm going to run it around like this I'm going to get pulled over a LOT. So need to figure out how to reduce the sound level a bit. If it was just loud at high rpms and higher loads then it wouldn't be such a huge issue, but it's loud at idle and low loads aswell. I started it up without mufflers for giggles and oh my god!! I didn't know an engine could be so loud!!
07-29-14, 01:12 PM
#1692
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i have smogged every rotary i've ever owned, although i've never failed CO, so no help there. the rotary will respond like a piston engine, generally though, so co should go down as you lean it out, and then go up when it starts lean misfiring.
i have also noticed that the scoot 4 rotor car did pass smog in Japan, and it runs an Rx8 airpump, so perhaps that would work. i do have some pr0n pics of the exhaust setup, they appear to have a cat they can put in, but it looks like it usually isn't.
as far as noise goes, i found with mine that tailpipe size is very important. with the 1x3" tailpipe its loud no matter how many mufflers i have inline. with the 2x2?" tip, its quieter than my FC. power isn't noticeably different, although on the street i'm not able to use it all anyways
i have also noticed that the scoot 4 rotor car did pass smog in Japan, and it runs an Rx8 airpump, so perhaps that would work. i do have some pr0n pics of the exhaust setup, they appear to have a cat they can put in, but it looks like it usually isn't.
as far as noise goes, i found with mine that tailpipe size is very important. with the 1x3" tailpipe its loud no matter how many mufflers i have inline. with the 2x2?" tip, its quieter than my FC. power isn't noticeably different, although on the street i'm not able to use it all anyways
07-29-14, 02:54 PM
#1694
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07-30-14, 09:18 AM
#1696
Fixed everything up yesterday. I ended up making a more restrictive removable DB-killer that worked pretty well, which took care of the DB level, Then I set the idle to 1000rpm, and leaned it out, I managed to get it to a lambda of 0.9 (1:13.2 AFR), any leaner and the engine would stall. CO was about 4,3% at that point, which was below the 4,5% required to pass 
Also fixed all the other stuff so the car passed! It's now road legal
I think I'm going to try to get the cruising part dialed in on the road (The paid version of tunerstudio is so awesome for this), also need to work out some minor stuff, the oil pan started sweating a bit, and the alignment is off, and my oil pressure gauge is starting to crap out, and I'm thinking about mounting 4 EGT bungs in the exhaust, I have some room left on my switch panel that could hold a LCD screen nicely!
Also fixed all the other stuff so the car passed! It's now road legal
I think I'm going to try to get the cruising part dialed in on the road (The paid version of tunerstudio is so awesome for this), also need to work out some minor stuff, the oil pan started sweating a bit, and the alignment is off, and my oil pressure gauge is starting to crap out, and I'm thinking about mounting 4 EGT bungs in the exhaust, I have some room left on my switch panel that could hold a LCD screen nicely!
07-30-14, 10:28 AM
#1697
Fixed everything up yesterday. I ended up making a more restrictive removable DB-killer that worked pretty well, which took care of the DB level, Then I set the idle to 1000rpm, and leaned it out, I managed to get it to a lambda of 0.9 (1:13.2 AFR), any leaner and the engine would stall. CO was about 4,3% at that point, which was below the 4,5% required to pass
Also fixed all the other stuff so the car passed! It's now road legal
I think I'm going to try to get the cruising part dialed in on the road (The paid version of tunerstudio is so awesome for this), also need to work out some minor stuff, the oil pan started sweating a bit, and the alignment is off, and my oil pressure gauge is starting to crap out, and I'm thinking about mounting 4 EGT bungs in the exhaust, I have some room left on my switch panel that could hold a LCD screen nicely!
Also fixed all the other stuff so the car passed! It's now road legal
I think I'm going to try to get the cruising part dialed in on the road (The paid version of tunerstudio is so awesome for this), also need to work out some minor stuff, the oil pan started sweating a bit, and the alignment is off, and my oil pressure gauge is starting to crap out, and I'm thinking about mounting 4 EGT bungs in the exhaust, I have some room left on my switch panel that could hold a LCD screen nicely!
Have you looked at thicker walls on your exhaust as a way to decrease noise?
07-31-14, 04:15 PM
#1698
Mmmm not really, I don't think it makes a huge difference. I drove the car for about 40 miles or so, and the noise isn't that bad the way it is right now, but when you get on the gas it get's insanely loud. Louder than exhaust noise!
It's nice to finally be able to do some driving! I did some messing with the mapping, and I got it to a point where I can drive it around ok, no full throttle or high rpm's or anything like that yet though, I need a dyno for that. Need to investigate my lambda meter first because it's showing wierd numbers, I'm wondering if the raw fuel and oil didn't mess the sensor up. It just reads extremely rich all the time. I tried tuning it so it reads normal AFR's but it's just not possible, the car just does not run with AFR's leaner than 1:12. I tried turning the autotune on, and it just messed up my fuel map so bad that the car wouldn't run in 5 minutes or so. After that I manually edited the VE map untill it drove around ok, but now it shows between 1:10 and 1:11 all the time. It's just a bosch lsu 4.9 with a bosch c125 based controller, never had any problems with it but there's a first for everything I guess. I think I have an innovate mtx lambda around somewhere.
Apart from that it is pretty awesome to drive! The sound at 4000 rpm is already awesome, can't wait to find out what 8000 sounds like!
It's nice to finally be able to do some driving! I did some messing with the mapping, and I got it to a point where I can drive it around ok, no full throttle or high rpm's or anything like that yet though, I need a dyno for that. Need to investigate my lambda meter first because it's showing wierd numbers, I'm wondering if the raw fuel and oil didn't mess the sensor up. It just reads extremely rich all the time. I tried tuning it so it reads normal AFR's but it's just not possible, the car just does not run with AFR's leaner than 1:12. I tried turning the autotune on, and it just messed up my fuel map so bad that the car wouldn't run in 5 minutes or so. After that I manually edited the VE map untill it drove around ok, but now it shows between 1:10 and 1:11 all the time.
It's just a bosch lsu 4.9 with a bosch c125 based controller, never had any problems with it but there's a first for everything I guess. I think I have an innovate mtx lambda around somewhere.Apart from that it is pretty awesome to drive! The sound at 4000 rpm is already awesome, can't wait to find out what 8000 sounds like!
08-01-14, 11:50 AM
#1700
Senior Member
On the stuck reading for afr, Id say the fuel killed it, make sure you have a decent distance on the sensor from the exhaust port so that the heat itself wont kill it either. I too want to see a 4k rpm video