Making The Case For The <Rotary> Powered FD: The Fix
01-20-09, 08:43 AM
#129
Racing Rotary Since 1983
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Brian Cain (BDC) has a very interesting thread going in the Auxiliary Injection section.
Brian is exploring whether the FD/FC can work well without an intercooler... relying on methanol AI to cool the motor.
it is really great to see board members doing R&D. especially for me since it is 9 degrees outside in wisconsin. (of course that just means i am doing it inside
)
anyway, a couple of very interesting items from Brian.
1. Brian did a comparative study on intake air temps (IAT) generated from taking air from within the engine compartment and from outside the engine compartment.
he found a 40 degree temp reduction from outside engine air!
this is the free-est of the free engine hp and longevity enhancement. we work so hard using every trick in the book to cool our engines and make more hp. cooler air means more oxygen molecules per volume, means we can add more fuel and make more hp. cooler air means less chance of knock.
a free lunch for your motor.
everyone who is currently drawing (160 degree) engine compartment air should go back to the drawing board and find a way to connect to the Great Outdoors. and i am not talking the Pettit deal which maybe draws a small amount of outside air. i am talking outside
anyone that feels they have a well engineered outside air setup is encouraged to share it within this thread.
2. Brian is examining switching methanol for the intercooler. he currently is running no intercooler. as his methanol switches on his intake air temps drop from triple digits to 75 degrees while his boost rises from 0 to one bar! thanks to the methanol.
my view is that for some running no IC could work fine. cruising and an occasional straight line blast and you are covered w methanol.
road racing develops too much heat and the IC is additive, o k subtractive, but in an additive way. Brian likes the improved spool/response without the IC. i like the always-taking-heat-out-of-the-engine of the IC.
in support of the IC...
air coming out of a turbo at 20 psi is often close to 300 degrees. i have relocated my IAT sensor to just after the IC. it is BEFORE my methanol. looking at my last dyno run my air temp sensor registered 33 C 91F! that means my IC took close to 200 degrees out of my intake air temps! that's before my meth cooling. no wonder my UIM is very very cold to the touch after a run. and this took place on a dyno where there was little airflow thru the IC.
perhaps the takeaway from Brian's research to date is that even without the aid of an IC, methanol is demonstrating an amazingly powerful ability to COOL. add an efficient intercooler and we are talking arctic.
which is just the opposite of what you are feeding your motor if you are not running AI.
hc
Brian is exploring whether the FD/FC can work well without an intercooler... relying on methanol AI to cool the motor.
it is really great to see board members doing R&D. especially for me since it is 9 degrees outside in wisconsin. (of course that just means i am doing it inside
)anyway, a couple of very interesting items from Brian.
1. Brian did a comparative study on intake air temps (IAT) generated from taking air from within the engine compartment and from outside the engine compartment.
he found a 40 degree temp reduction from outside engine air!
this is the free-est of the free engine hp and longevity enhancement. we work so hard using every trick in the book to cool our engines and make more hp. cooler air means more oxygen molecules per volume, means we can add more fuel and make more hp. cooler air means less chance of knock.
a free lunch for your motor.
everyone who is currently drawing (160 degree) engine compartment air should go back to the drawing board and find a way to connect to the Great Outdoors. and i am not talking the Pettit deal which maybe draws a small amount of outside air. i am talking outside
anyone that feels they have a well engineered outside air setup is encouraged to share it within this thread.
2. Brian is examining switching methanol for the intercooler. he currently is running no intercooler. as his methanol switches on his intake air temps drop from triple digits to 75 degrees while his boost rises from 0 to one bar! thanks to the methanol.
my view is that for some running no IC could work fine. cruising and an occasional straight line blast and you are covered w methanol.
road racing develops too much heat and the IC is additive, o k subtractive, but in an additive way. Brian likes the improved spool/response without the IC. i like the always-taking-heat-out-of-the-engine of the IC.
in support of the IC...
air coming out of a turbo at 20 psi is often close to 300 degrees. i have relocated my IAT sensor to just after the IC. it is BEFORE my methanol. looking at my last dyno run my air temp sensor registered 33 C 91F! that means my IC took close to 200 degrees out of my intake air temps! that's before my meth cooling. no wonder my UIM is very very cold to the touch after a run. and this took place on a dyno where there was little airflow thru the IC.
perhaps the takeaway from Brian's research to date is that even without the aid of an IC, methanol is demonstrating an amazingly powerful ability to COOL. add an efficient intercooler and we are talking arctic.
which is just the opposite of what you are feeding your motor if you are not running AI.
hc
01-20-09, 12:48 PM
#130
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About how long do you guys think a gallon of water/meth is going to last in one of these systems with aggressive street driving? I'm sort of curious about the long term care and feeding of the system. Wondering about the edge case of running out of meth while crossing the dessert 
But seriously, wondering how often a person would need to fill the tanks.
But seriously, wondering how often a person would need to fill the tanks.
01-20-09, 08:25 PM
#131
About how long do you guys think a gallon of water/meth is going to last in one of these systems with aggressive street driving? I'm sort of curious about the long term care and feeding of the system. Wondering about the edge case of running out of meth while crossing the dessert But seriously, wondering how often a person would need to fill the tanks.
But seriously, wondering how often a person would need to fill the tanks.If you run a 300cc/min injector at 100% duty cycle at full throttle, you would get 12 1/2 minutes of full throttle running. That is a long time at full throttle, but probably not as long as you want. If you are road coursing, I think you would want a considerably larger tank for your ai system.
01-20-09, 08:46 PM
#132
BDC Motorsports
In the past few days of screwing around w/ the car, I've plowed through a whole gallon of alcohol. Granted, on the previous day of beating the car up I was throwing alot more at the motor than I am right now. But nonetheless, it might be wise for those to look at a gallon-sized fuel cell as minimum and for those doing a road race setup may want to do something larger.
B
B
01-20-09, 11:07 PM
#133
Thanks to afgmoto1978 for building this.
(I helped, and learned a heck of a lot in the process)
Anyway, the K&N cone filter is inside a box formed by the radiator, and the walls on both sides of the filter.
Air comes to the filter directly from the inlet in the front of the car as the pics will show.
It's kind of hard to tell from just the pics, but the box formed by the rad, fiberglass walls, and 1/2" rigid fiberglass insulation on the driver side make a fairly good seal.
No engine compartment air here. True it is right next to the rad, but the incoming air seems to negate that for the most part.
Highest intake temps I have seen are about 120f, right after an autox run, on a 95f day.
I did 1 track day in October, it was about 70f that day. I didn't really pay attention to intake temps, but water and oil never got far past the tstats opening.
I just started racing the car again about August or so last year, an plan to get a little more time with it this year, and a better idea on intake temps.
01-21-09, 07:55 AM
#134
Racing Rotary Since 1983
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"About how long do you guys think a gallon of water/meth is going to last in one of these systems with aggressive street driving"
this is an excellent question... how much AI do i use... how big a tank...
of course we all understand that it depends on what you are doing w your car. there's driving around w occasional boosted romps, there are 30 minute road racing ontrack sessions and a day at the quarter mile.
it also depends greatly on your AI injectant choice:
there is a limit to how much water you can inject as it doesn't burn and too much will put out your combustion. so water... around 300 to 500 CC/Minute.
alcohol can be anything you want from zero to 100% of your fuel. generally most use alcohol to make more power and i find that from 900 to 1800 CC/Min works great. i run 1400.
so obviously alcohol injectant requires a larger tank. i currently run a 4 gallon fuel cell for my meth.
here's a back of the envelope estimate:
at 1400 CC/Min max deliverability.
if you run for 15 minutes at max you use 5.5 gallons. now notice my delivery chart... you will see that 100% is a modest section. in fact at 15 psi i am at 65% deliverability. 100% is at peak torque and notice it scales back towards top end just like your fuel map. (BTW, the ability to tailor delivery INDEPENDENT of boost is one of the (many) advantages of the HD AI system).. take a good look at this chart.
given that there are times when you are on the brakes or slowing as the corvette in front of you that you are lapping is blocking you or that you are in and out of the pits for tire temps etc a 4 gallon capacity will work for a 30 minute session.
last sep i did 23 4th gear 2000-8200 dyno pulls w my FJO system and at the end of the session my level had hardly been scratched. so you should be able to do alot of drag racing w 4 gallons. (it would be easy to do the math on drag racing... say 12 seconds on the throttle at 1400 CC/Min. you would be replacing your drag rubber before refilling the tank.)
w water, say at 500 CC/Min, you extend these numbers by about a factor of 3. stated differently, my 4 gallon cell would need to be about 1.5 gallons to offer similar service.
here are a couple of pics of my present 4 gallon setup
most AI systems offer a (GM derived) low level LED that works well and is simple to install in your tank.
PDViper77 posted an eye-opening picture in his GT42 build thread (3rd Gen section)
i really like how the FD opens up so easily in the rear hatch area. i have been thinking about ditching the stock gas tank and running two fuel cells... one for pump and one for meth. PD is in process of doing the exact same thing. i wonder if he has been tapping in to my brain... i like the area is a non structual from rigidity aspect, i like it is boxed. i like it offers tons of room. i like that i can end up w a lower center of mass and finally, it will clean up so i can reinstall my carpet and have additional storage. i have contacts w a major fuel cell co from my racing days and would like to get a custom fit twin setup made. maybe other FD owners would be interested. i will update the thread re this...
howard
this is an excellent question... how much AI do i use... how big a tank...
of course we all understand that it depends on what you are doing w your car. there's driving around w occasional boosted romps, there are 30 minute road racing ontrack sessions and a day at the quarter mile.
it also depends greatly on your AI injectant choice:
there is a limit to how much water you can inject as it doesn't burn and too much will put out your combustion. so water... around 300 to 500 CC/Minute.
alcohol can be anything you want from zero to 100% of your fuel. generally most use alcohol to make more power and i find that from 900 to 1800 CC/Min works great. i run 1400.
so obviously alcohol injectant requires a larger tank. i currently run a 4 gallon fuel cell for my meth.
here's a back of the envelope estimate:
at 1400 CC/Min max deliverability.
if you run for 15 minutes at max you use 5.5 gallons. now notice my delivery chart... you will see that 100% is a modest section. in fact at 15 psi i am at 65% deliverability. 100% is at peak torque and notice it scales back towards top end just like your fuel map. (BTW, the ability to tailor delivery INDEPENDENT of boost is one of the (many) advantages of the HD AI system).. take a good look at this chart.
given that there are times when you are on the brakes or slowing as the corvette in front of you that you are lapping is blocking you or that you are in and out of the pits for tire temps etc a 4 gallon capacity will work for a 30 minute session.
last sep i did 23 4th gear 2000-8200 dyno pulls w my FJO system and at the end of the session my level had hardly been scratched. so you should be able to do alot of drag racing w 4 gallons. (it would be easy to do the math on drag racing... say 12 seconds on the throttle at 1400 CC/Min. you would be replacing your drag rubber before refilling the tank.)
w water, say at 500 CC/Min, you extend these numbers by about a factor of 3. stated differently, my 4 gallon cell would need to be about 1.5 gallons to offer similar service.
here are a couple of pics of my present 4 gallon setup
most AI systems offer a (GM derived) low level LED that works well and is simple to install in your tank.
PDViper77 posted an eye-opening picture in his GT42 build thread (3rd Gen section)
i really like how the FD opens up so easily in the rear hatch area. i have been thinking about ditching the stock gas tank and running two fuel cells... one for pump and one for meth. PD is in process of doing the exact same thing. i wonder if he has been tapping in to my brain... i like the area is a non structual from rigidity aspect, i like it is boxed. i like it offers tons of room. i like that i can end up w a lower center of mass and finally, it will clean up so i can reinstall my carpet and have additional storage. i have contacts w a major fuel cell co from my racing days and would like to get a custom fit twin setup made. maybe other FD owners would be interested. i will update the thread re this...
howard
Last edited by Howard Coleman; 01-21-09 at 08:18 AM.
01-21-09, 09:24 AM
#135
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With the additional electrical draw from ignition components, pump(s) and injector control units (etc, etc), is there a point beyond which the stock alternator can't keep up?
///yes, but i haven't found it yet, and i have alot of stuff on board. hc///
///yes, but i haven't found it yet, and i have alot of stuff on board. hc///
Last edited by Howard Coleman; 01-21-09 at 10:20 AM.
01-21-09, 10:12 AM
#136
Sounds like you'll run out of Alcohol / Meth during a track weekend unless you bring your own refills. If I go this route, I think I'll stick to water. The car is full of stuff as it is whenever I go to the track.
///you'll want to run distilled water... so you probably will be bring it along, though only 35% of the equivalent meth. plus things get hot at the track and you can just drink any excess. not advised w meth... i am VERY interested in what we will be able to do w an FJO HD AI system and water. hc///
///you'll want to run distilled water... so you probably will be bring it along, though only 35% of the equivalent meth. plus things get hot at the track and you can just drink any excess. not advised w meth... i am VERY interested in what we will be able to do w an FJO HD AI system and water. hc///
Last edited by Howard Coleman; 01-21-09 at 10:23 AM.
01-21-09, 10:45 AM
#137
Racing Rotary Since 1983
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i disassembled a JDM motor for a client sunday and thought you all would like to see a pic of one of the rotors... the motor is in class A condition overall and will make a super 500 rwhp AI machine but just look carefully at all the carbon!
this rotor came out of a low mileage excellent condition (dimensionally) motor! the problem is all the additional fuel mazda used to cool the motor along with non 2 cycle oil from the crankcase being pumped into the combustion chamber by the external oil pump.
the fix is lose the external oil pump or convert it to inject 2 cycle oil using the Rotary Aviation kit, or just use premix as i did.... and use AI to clean your internals.
the irregular carbon deposits on the rotor face create a 'glow plug' effect ala diesel and all of a sudden we have preignition.
of course carbon glunks up the apex seal grooves and side seal grooves. half the motors i take apart have sticking seals... all due to a combo of carbon and too much crankcase oil and fuel. sort of superglue in your motor
AI engines have very little carbon deposits.
hc
this rotor came out of a low mileage excellent condition (dimensionally) motor! the problem is all the additional fuel mazda used to cool the motor along with non 2 cycle oil from the crankcase being pumped into the combustion chamber by the external oil pump.
the fix is lose the external oil pump or convert it to inject 2 cycle oil using the Rotary Aviation kit, or just use premix as i did.... and use AI to clean your internals.
the irregular carbon deposits on the rotor face create a 'glow plug' effect ala diesel and all of a sudden we have preignition.
of course carbon glunks up the apex seal grooves and side seal grooves. half the motors i take apart have sticking seals... all due to a combo of carbon and too much crankcase oil and fuel. sort of superglue in your motor
AI engines have very little carbon deposits.
hc
01-21-09, 11:55 AM
#138
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What do you think would happen if you added AI to a motor that has this level of carbon on the internals? Do you think there is risk that the effect of AI might be dislodging some of the gunk causing issues?
01-21-09, 12:14 PM
#139
Great info once again, I'm interested in the dual fuel cell as well. I went the same route as the pic above as far as removing the stock tank and deck. I'll be needing a setup with enough capacity for driving moderate distances without having to refuel. What size dual fuel cell would fit with it mounted under the carpeted area?
01-21-09, 02:46 PM
#140
Racing Rotary Since 1983
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"What do you think would happen if you added AI to a motor that has this level of carbon on the internals? Do you think there is risk that the effect of AI might be dislodging some of the gunk causing issues?"
a fair question... and i don't have an answer other than to observe that eventually the seals in the rotor above will cease working. most motors that have run AI and have been later torn down look clean and no doubt they started out w a bit of carbon.
hc
a fair question... and i don't have an answer other than to observe that eventually the seals in the rotor above will cease working. most motors that have run AI and have been later torn down look clean and no doubt they started out w a bit of carbon.
hc
01-21-09, 04:40 PM
#142
Racing Rotary Since 1983
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methanol washes away everything, including carbon. since you don't run around in boost all the time it is a non issue. after 14,000 miles w meth AI all my bearings look new and my side seal wear was .001. no external oil pump, just 1/2 ounce of any 2cycle oil per gallon and 1 oz when dynoing or racing.
case closed.
hc
case closed.
hc
01-21-09, 07:59 PM
#144
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the apex seals (3 mm) looked exactly as they did when i built the motor 4 years ago.
while a water/meth mix delivers benefits it is important to run the same ratio water to alcohol consistantly. (this assumes you "tuned up" a bit to take advantage of the alcohol.) if you choose not to tune up, it is probably less bother to just run water.
just a guess to help you out... probably no more than 500 CC/Min at 400 rwhp for either water or water/meth.
i have no direct experience w running water or a mix. there are many on this forum (more than you'd think) that have experience and they are invited to contribute.
hc
while a water/meth mix delivers benefits it is important to run the same ratio water to alcohol consistantly. (this assumes you "tuned up" a bit to take advantage of the alcohol.) if you choose not to tune up, it is probably less bother to just run water.
just a guess to help you out... probably no more than 500 CC/Min at 400 rwhp for either water or water/meth.
i have no direct experience w running water or a mix. there are many on this forum (more than you'd think) that have experience and they are invited to contribute.
hc
01-21-09, 08:23 PM
#145
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IS there possibly a good way to "Steam Clean" the engine just to keep the carbon build up lower, if you dont need the use of AI? I would imagine a bit of water down one of the vacuum nipples in the end of the UIM would work?
01-21-09, 08:37 PM
#146
There is actually a process to doing just that with distilled water. I can say that once you get too much build up, I doubt idling and ingesting water will really help. I think the high rpm and high load combined with water is really what helps keep these things clean.
01-21-09, 09:16 PM
#147
Here are a couple:
https://www.rx7club.com/showthread.p...m+clean+engine
https://www.rx7club.com/showthread.p...m+clean+engine
01-22-09, 09:05 AM
#148
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I've ordered a new motor and turbo kit. I plan for 18-19psi on a gt35r with AI. I hope this reaches somewhere around 425rwhp.
I was talking to a local shop who is going to help me with the work, and I asked them which AI system they use. The tuner told me they use aquamist and I asked how it is tuned and he said you can tune the amount of injectant based on injector duty cycle. He also said the kit was $350.
Howard, would you consider a setup tuned on injector duty cycle as HD?
I was talking to a local shop who is going to help me with the work, and I asked them which AI system they use. The tuner told me they use aquamist and I asked how it is tuned and he said you can tune the amount of injectant based on injector duty cycle. He also said the kit was $350.
Howard, would you consider a setup tuned on injector duty cycle as HD?
01-22-09, 11:07 AM
#149
Racing Rotary Since 1983
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Gordon,
not to exclude the meth/hp camp, but i completely agree w your post and look forward to lots more participation from FD owners running simple inexpensive water systems that solve the turbo'd rotary's heat problems.
let's hear from you as i know you are out there.
hc
not to exclude the meth/hp camp, but i completely agree w your post and look forward to lots more participation from FD owners running simple inexpensive water systems that solve the turbo'd rotary's heat problems.
let's hear from you as i know you are out there.
hc
01-22-09, 12:31 PM
#150
Forgive me for asking a really really stupid question but at the risk of being flamed for not searching or reading enough Im going to do it anyway.
What happens if you tune your car and get WI installed later?
What happens if you tune your car with WI installed and run out of water under WOT (during regular spirited driving specifically)?
What happens if you tune your car and get WI installed later?
What happens if you tune your car with WI installed and run out of water under WOT (during regular spirited driving specifically)?