4 rotor FC ?
#51
Uh, no. I am showing my total ignorance of the displacement of the Mercedes engine- as j9fd3s pointed out. It was 4.8l- wow!
I think 850hp is no problem w/ that and some advancements in design; but this was about a 4 rotor made of 13B parts.
If Mazda has done 700hp w/ 787B that reliably, then 850hp is most likely possible.
BSFC? How the heck do you get that w/out knowing the HP of the engine? That is Lbs/hr of fuel flow divided by HP, right? Ignorance?
Oh no, over 10,000 rpm on a P-port...Huh?
I think 850hp is no problem w/ that and some advancements in design; but this was about a 4 rotor made of 13B parts.
If Mazda has done 700hp w/ 787B that reliably, then 850hp is most likely possible.
BSFC? How the heck do you get that w/out knowing the HP of the engine? That is Lbs/hr of fuel flow divided by HP, right? Ignorance?
Oh no, over 10,000 rpm on a P-port...Huh?
#52
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we talked to koby at last years montery historics, and the 787 motor could have run another 24hrs before needing a rebuild, so if you were willing to live with less engine life there should be more power there. also they were shifting at 7000rpm.
mike
mike
#53
Also they were running a fairly lean fuel mixture (I'd guess 15-16:1) for fuel economy reasons. Fuel economy is a big factor at LeMans as they are only allowed a certain amount of fuel for the 24 hours.
#56
I think all of you guys looking for a 4-rotor should try realistically using the power you can get from a 3-rotor. With mine running in only a moderate state of tune I was breaking traction in 5th gear at 200km/h, so why bother going for more power.
Bitcn' , I saw the 4-rotor Jeff built the other day while I was in Auckland. I met up with Jeff that Saturday night after the dyno work and I went to his workshop to see all the goodies he is working on. All I could say is WOW!
Mine only had overheating problems when trying to drive the car in 40C+ temperature days. Until you live through a Sydney heatwave you have not lived ;-) I already have plans for it to get a custom alloy radiator so there is no chance period of overheating. Also the thermo is getting the **** and I will be putting the engine fan back on with a custom shroud. With the motor going back in the car over the next few weeks, and a million and one things fixed up since it was last running, who knows what it will go like this time. To keep the record straight, my motor failed due to hitting the sump bolt with something which tore it out and lost all the oil. My fault for not watching the oil pressure.
It is funny, after chasing horsepower...horsepower....horsepower for so long, once I got it I want to tame it down. I built my car for circuit work and now my ideas on power have changed. Now I want something more progressive in its delivery with no sudden hit in the powerband, and have it come in as early as possible. As I learned, be careful what you wish for...
And for those intersted. A 4-rotor will fit in a 1st Gen engine bay without too much drama. Have a look at my 3-rotor and how well it fits. (www.hitman.hm/rx7.htm) I will already be shifting the intercooler and radiator forward to give some more room, just incase I get tired of the 3-rotor and want to run a mild port 4-rotor aspirated. I am not dumb enough to believe the chassis will handle a turbo version.
Bitcn' , I saw the 4-rotor Jeff built the other day while I was in Auckland. I met up with Jeff that Saturday night after the dyno work and I went to his workshop to see all the goodies he is working on. All I could say is WOW!
Mine only had overheating problems when trying to drive the car in 40C+ temperature days. Until you live through a Sydney heatwave you have not lived ;-) I already have plans for it to get a custom alloy radiator so there is no chance period of overheating. Also the thermo is getting the **** and I will be putting the engine fan back on with a custom shroud. With the motor going back in the car over the next few weeks, and a million and one things fixed up since it was last running, who knows what it will go like this time. To keep the record straight, my motor failed due to hitting the sump bolt with something which tore it out and lost all the oil. My fault for not watching the oil pressure.
It is funny, after chasing horsepower...horsepower....horsepower for so long, once I got it I want to tame it down. I built my car for circuit work and now my ideas on power have changed. Now I want something more progressive in its delivery with no sudden hit in the powerband, and have it come in as early as possible. As I learned, be careful what you wish for...
And for those intersted. A 4-rotor will fit in a 1st Gen engine bay without too much drama. Have a look at my 3-rotor and how well it fits. (www.hitman.hm/rx7.htm) I will already be shifting the intercooler and radiator forward to give some more room, just incase I get tired of the 3-rotor and want to run a mild port 4-rotor aspirated. I am not dumb enough to believe the chassis will handle a turbo version.
#57
J9FD3S : Mazda quote that they were revving to 9500, with peak power at 9000rpm. If they were only going to rev to 7000 they would have been better to stick with a mild bridgeport or even an extend port which would have run more stable at leaner mixtures.
True though about the reliability.
Oh yeah, I forgot to mention that anyone looking at running a 3 or 4 rotor should bear in mind that the new Haltech coming in a short time has already had the coding done for both 3 and 4 rotors. Sequential and staged injection, full 3D Trail timing control, and even mappable control of the oil metering pump. No need for multiple ECU's to do the job. Food for thought....
True though about the reliability.
Oh yeah, I forgot to mention that anyone looking at running a 3 or 4 rotor should bear in mind that the new Haltech coming in a short time has already had the coding done for both 3 and 4 rotors. Sequential and staged injection, full 3D Trail timing control, and even mappable control of the oil metering pump. No need for multiple ECU's to do the job. Food for thought....
#58
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i agree with you on the hp thing, it is possible to get "too much" .
the 7500rpm thing was straight from koby's mouth, they flew him and the car out the the us last summer and we got to talk to him, he's a very enthusiastic guy, and he happend to mention that in passing
mike
the 7500rpm thing was straight from koby's mouth, they flew him and the car out the the us last summer and we got to talk to him, he's a very enthusiastic guy, and he happend to mention that in passing
mike
#60
Yeap, stock clutch fan. Nothing pumps air like those things. Forget a thermofan, it might do in cold climates but try driving in 44C (111F) conditions and they dont come close. A shroud and stock fan draw air through the enitre radiator, whereas a thermo alone only draws air through the circle it covers.
And besides, who cares about loosing 5hp when you have hundreds to spare.
And besides, who cares about loosing 5hp when you have hundreds to spare.
#62
Originally posted by codeseven21
That reminds me, the hitman (www.hitman.au) has been working on a 4-rotor 1st gen. If he can do that, then for sure a 2nd gen is possible.
That reminds me, the hitman (www.hitman.au) has been working on a 4-rotor 1st gen. If he can do that, then for sure a 2nd gen is possible.
#64
Does anyone have any idea how the rear counterweight from the front engine and the front counterweight from the rear engine are fit on the shaft in either the Jeff Bruce or Yashiro designs? Just curious. Also, what is used for a center housing (between the two engines)?
And what about ignition? Do they use two distributors, or modify one? Are both plugs per rotor used?
I'd be interested in seeing one of these...
Ren
And what about ignition? Do they use two distributors, or modify one? Are both plugs per rotor used?
I'd be interested in seeing one of these...
Ren
#65
P.S.
Peejay,
I know you probably get asked this a lot, but what the hell is that under your name, above your avatar? I managed to figure out elite rotary, but what is H4XOR?
And what is in the picture you have as your avatar?
Ren
Peejay,
I know you probably get asked this a lot, but what the hell is that under your name, above your avatar? I managed to figure out elite rotary, but what is H4XOR?
And what is in the picture you have as your avatar?
Ren
#66
90º apart. That allows the engine to produce power pulses every 90º instead of every 180º like it would if they were allowed to fire at the same time, or a regualr two rotor (if that makes any sence). The distributor could be done any number of ways.
peejay is an elite rotary hacker. That's what he did to the thing(s) in the avatar pic. The rotor housing has had its apex seal haxored in a very leet way (uhg, I hate leet speak).
peejay is an elite rotary hacker. That's what he did to the thing(s) in the avatar pic. The rotor housing has had its apex seal haxored in a very leet way (uhg, I hate leet speak).
#67
Originally posted by Jeff20B
90º apart. That allows the engine to produce power pulses every 90º instead of every 180º like it would if they were allowed to fire at the same time, or a regualr two rotor (if that makes any sence). The distributor could be done any number of ways.
90º apart. That allows the engine to produce power pulses every 90º instead of every 180º like it would if they were allowed to fire at the same time, or a regualr two rotor (if that makes any sence). The distributor could be done any number of ways.
As for the timing, what i was trying to understand is how those that have done it, did it. It seems you would be able to use two CAS's, or maybe just add 2 more teeth to the top reluctor. The latter sounds like a more feasible option, since it would be rather difficult to accomodate a second CAS sticking out of the center housing...
peejay is an elite rotary hacker. That's what he did to the thing(s) in the avatar pic. The rotor housing has had its apex seal haxored in a very leet way (uhg, I hate leet speak).
Ren
#70
Originally posted by autocrash
You guys are putting evil EVIL ideas in my head... stop it!!! I'm already broke enough dammit!! I want more money... so I can start a 6 rotor!!! (j/k)
You guys are putting evil EVIL ideas in my head... stop it!!! I'm already broke enough dammit!! I want more money... so I can start a 6 rotor!!! (j/k)
#71
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From: https://www2.mazda.com/en/100th/
Originally posted by Attila the Fun
See http://www.hurley-engineering.ltd.uk/ and click on the "Dreams" link.
See http://www.hurley-engineering.ltd.uk/ and click on the "Dreams" link.
mike
#72
Originally posted by j9fd3s
if i do another big project, i'm thinking about a 20b (r26b would be even better) in something like a 27 track roadster, or maybe a copy of a late 50's gp car, or a tube frame rotary tr3 would be cool too
mike
if i do another big project, i'm thinking about a 20b (r26b would be even better) in something like a 27 track roadster, or maybe a copy of a late 50's gp car, or a tube frame rotary tr3 would be cool too
mike
Another prospect: http://www.kitcar.com/beck/home.html
The Lister replica which ran in the 2000 One Lap of America weighed in at 1800 lb. >with< a small-block Chevy V-8 producing 550 hp. With a 20B, you'd probably need a license from the FAA to run it.
#74
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actually the tr3 idea keeps coming back, maybe it is the way to go. i dont know anyone who makes a kit, nice drivers like mine are still under 10k. probably something like this one http://cgi.ebay.com/ebaymotors/ws/eB...tem=1854839138
or worse cause you wouldn't end up with much stock triumph , i was also thinking 13bt, its a small car
mike
or worse cause you wouldn't end up with much stock triumph , i was also thinking 13bt, its a small car
mike