Tore down engine. Heres whats wrong!!
#51
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Originally posted by von
Morons.
Morons.
When you drag 1/4 and do experimental stuff you really dont need all the clearancing and balancing ****.
NZ Conv whats up ??? How many engines have you rebuilt ?
You guys sound like a lefties ( political ) unwiling to listen to reason.
No one here really cares what you do with your engine (like you said, it's your engine), we're just trying to share some knowledge with you. Do with it what you will, but don't get all upset about it and resort to name-calling.
#53
Rotary Freak
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Chill out about the name calling baby.
Expierienced advice huh NZ ?
Gluing my side apex is good advice ?
Whatever I dont care im not trying to convince anyone I really dont care.
Does anyone know the answer to my ? or do I have to use new side plates and report ???
Expierienced advice huh NZ ?
Gluing my side apex is good advice ?
Whatever I dont care im not trying to convince anyone I really dont care.
Does anyone know the answer to my ? or do I have to use new side plates and report ???
#54
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Well, just think about it. You put 400 miles on that engine without the seal falling through, it seems a little odd that it'd just fall through all of a sudden after 400 miles instead of 1 or 2, I'm guessing you detonated and cracked it. Solid would help keep them in one peice better, but I don't think 'falling in' was your problem to start.
#55
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Good logical thinking. well that brings up other issues then. Thnx I didnt think of that but the best guess now would be heat from the timing cracked it. Mabey detonation but I was only cruizing during break in. So I guess I will use the old housings and start over. Although My car is parted out already Im going to need a doner car or someone to just buy it.
#57
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Alright Von my N/A buddy, ya need to clam down a wee. But personally I would get new irons and report. I have been spending a bit of time at pine appleracing, and I have never seen rob make a port anywhere near that shitty. I would suggest taking it to a different place to have them ported, cuz that dude didn't do a very good job.
Hell that port looks as crappy as me trying to blend my AFM adapter, and my hands shake like a sun ofa bitch.
Hell that port looks as crappy as me trying to blend my AFM adapter, and my hands shake like a sun ofa bitch.
#59
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The exaust ports are fine. Its not that huge. Its just matched to the Sleeve. If you feel with your hand thiers a lip between the sleeve and the housing. That lip was grinded away much less than the mazdatrix websites exaust porting. Also the port does not have to be pretty in order to amke power. I dont know where you came up with that idea. It obviously flows way more than stock. These guys port for basically free anyways. I wouldnt pay 700$ for a bridge or whatever mazdatrix charges.
#60
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Originally posted by von
. It obviously flows way more than stock.
. It obviously flows way more than stock.
I'd bet my car that a stock N/A primary port flows more than that port below 6K. You even said it wouldn't idle below what was it... 3K? I can take my car down to 399rpm (which is where the computer thinks the car is no longer running) and it will hold an idle on that line. (lopes like mad, but stays running) And I have more port timing than you do! I also have close to 7K on my engine without any issues.
You've killed the intake charge velocity, which has far more to do with flow characteristics than the throat of the port. If you don't believe me, think of which will flow more, a garden hose at 1psi or a soda straw at 100?
#61
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soda straw! soda straw!
i'm glad he's still arguing or else this thread would die and that would be bad. My official Idea is to weld the housings to each other, then you can spin to 12K just like you want to, since you don't need and hardened gears. oh, and next time, port into the water jackets, i heard that increases flow too.
i'm glad he's still arguing or else this thread would die and that would be bad. My official Idea is to weld the housings to each other, then you can spin to 12K just like you want to, since you don't need and hardened gears. oh, and next time, port into the water jackets, i heard that increases flow too.
#62
Rotary Freak
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I have no engine building expirience but maybe I can offer you some advise.
If you think the corner seal actually tweaked itself into getting caught slightly in the port then maybe you can try a different design corner seal spring?
Maybe if you get the type which has the 2 tiny springs it wont tend to tweak the seal like the stock 1st, 2nd, and 3rd gen springs. I dont remember who makes them but you can find them easily Im sure.
Again I have no real clue.
If you think the corner seal actually tweaked itself into getting caught slightly in the port then maybe you can try a different design corner seal spring?
Maybe if you get the type which has the 2 tiny springs it wont tend to tweak the seal like the stock 1st, 2nd, and 3rd gen springs. I dont remember who makes them but you can find them easily Im sure.
Again I have no real clue.
#63
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First off I can’t believe that you did not break into the water jacket port. 2nd Was that port design carefully designed/engineered, or was it done on the fly? It does not look like any time or engineering was taken into account when it was made. IE port timing, volumetric efficacy, usable RPM range, taken into account the primary use of the vehicle. In just my opinion your engine builder went mad and just started grinding away with out taking into account the ton of things that need to be addressed before something like this is done.
I would start with new housings do a good street port and if you “really” need more power then do a small bridge port. This is a proven, engineered, and carefully thought out way to port a motor. But do remember this proven idea of port design will change the dynamics of the motor making it less efficient down low and thus not a good drag car.
I would start with new housings do a good street port and if you “really” need more power then do a small bridge port. This is a proven, engineered, and carefully thought out way to port a motor. But do remember this proven idea of port design will change the dynamics of the motor making it less efficient down low and thus not a good drag car.
#65
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No offense man but you dont sound to knowlegable about what your doing. Looks like you just had them go at it without even really planning anything. The corners on the ports are all pointy and jagged which doesnt help flow characteristics, I mean, werent you the guy asking if you could "cheat" and just let the car idle for a long period of time to break it in?
#67
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Why dont you use a bridgeport, or peripheral port? Im sure they will work alot better than the godzilla port, or whatever port your using thats been proven by thousands of racers over years.
#68
Rotary Freak
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Jimmy ? what are you talking about...I never said I want usable power. I dont drive it on the street at all. Its just my project car to **** with so if you can idle at 400rpms woopy what the hell are you trying to say ? I was just going for as a narrow powerband as possible.
By the way on my stock port I was hitting 100 rpms
Hybrid racer ? Thiers a reputable shop that says you can let it idle to break it in...Especialy if its just for short period drag racing so this doesent really help you belittle me.
By the way on my stock port I was hitting 100 rpms
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Hybrid racer ? Thiers a reputable shop that says you can let it idle to break it in...Especialy if its just for short period drag racing so this doesent really help you belittle me.
#69
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Tony turbo11 ! yeah thats what Ill do... A bridge is coming next but its not going to be a full bridge. the dising of it should make it last as long as a streetport. Hopefully if it works I will post them up if the meckanics cool with it.
#70
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Originally posted by von
Jimmy ? what are you talking about...I never said I want usable power. I dont drive it on the street at all.
Jimmy ? what are you talking about...I never said I want usable power. I dont drive it on the street at all.
#71
mad scientist
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Von, youre arguments are the stupidest things Ive ever hears. Wanna know what seperates your port from people like Ito and Rob's? QUALITY. Ask anyone who really knows rotaries, and has experience with ports, and they will tell you smoothness is where power and reliability is. Your seals broke because they couldnt take the abuse from those sharp corners.
Back to your port design. It is simply the wrong shape for a n/a. The port is too long and narrow. It has more timing than a PP, but wastes a whole lot of that timing because it opens so late. So you would have a shitty low end, and the top end would not make up for it.
That flywheel *might* be able to take 13K, but everythin else that spins will have grenaded by 11k. at 10.5K, the shaft flex is enough to cause the rotors to start hitting the side housings, which breaks things very quickly. And thats with S5 rotors. S4 would happen a little sooner. Then your clutch or PP would explode, because stock type clutches are NOT made to go past 11K, and even thats pushing it.
I hope you werent planning on using stock bearings. You would spin a bearing the first time you hit 10K.
Do yourself a favor and have someone who actually knows what theyre doing build your engine, without you ever getting close to it until its together.
Back to your port design. It is simply the wrong shape for a n/a. The port is too long and narrow. It has more timing than a PP, but wastes a whole lot of that timing because it opens so late. So you would have a shitty low end, and the top end would not make up for it.
That flywheel *might* be able to take 13K, but everythin else that spins will have grenaded by 11k. at 10.5K, the shaft flex is enough to cause the rotors to start hitting the side housings, which breaks things very quickly. And thats with S5 rotors. S4 would happen a little sooner. Then your clutch or PP would explode, because stock type clutches are NOT made to go past 11K, and even thats pushing it.
I hope you werent planning on using stock bearings. You would spin a bearing the first time you hit 10K.
Do yourself a favor and have someone who actually knows what theyre doing build your engine, without you ever getting close to it until its together.
#72
Big big big port. There is a guy in Houston that has an engine with a port about that size but with a bridge also. The intermediate housing is also as large as he can get it. He is using a Holley carb and manifold in a tube frame VW dragster that weighs less than some of my turds. He has run in the high tens. Impressive yes but then you look at the reliability and powerband. He rebuilds his engines after about every 20-25 passes down the track in other words every 5 or 6 miles of use. He has tons of parts, lots of time, and too much money so he doesn't care. His power band STARTS to kick in at 8000 rpm and he shifts at 13000! Let me reiterate the lifespan of his engines. There are some times when he doesn't even get that many uses. If you want to make more power and be usable, take a different approach to it. Bigger is not always better, especially when it comes to port design. Velocity over volume (to a point). Clearancing is an issue on any engine that you intend to actually start and run at all. The reason you can't rev sky high (regardless of if its a rotary) is because of flex. The lack of a center bearing and therefore center support on the e-shaft causes it to flex at high rpm's. The more flex, the more clearancing you need right up to the point that the shaft stays bent or your rotors hit the side housings. Get a guru racing center bearing and rev up to about 9500 or so max.
Have you optimized your transmission and rear end ratios to match your new power band? If not you will never make impressive times on the street or track. Design around what you have. We all have neat ideas that we'd like to test. I at least applaud your willingness to try regardless of how it turned out or what it looks like. Do some more research, be a little more patient, and re-evalutate you goals and abilities at this stage. You'll get there one day.
Have you optimized your transmission and rear end ratios to match your new power band? If not you will never make impressive times on the street or track. Design around what you have. We all have neat ideas that we'd like to test. I at least applaud your willingness to try regardless of how it turned out or what it looks like. Do some more research, be a little more patient, and re-evalutate you goals and abilities at this stage. You'll get there one day.
#73
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Re: d
Originally posted by von
Morons. This is my engine. When you drag 1/4 and do experimental stuff you really dont need all the clearancing and balancing ****. How many times will I have to say this...My friends motor with just about the same port is still going strong after 1 year. He constintly hits 12k
NZ Conv whats up ??? How many engines have you rebuilt ? I reved my engine to the limiter for 5 seconds ask nitronick!!! Right after that I took apart the engine and guess what ? clean as a wistle. No chatter , no nothing even with heavy shity S4 rotors and unbalanced S5 flywheel ( OHH NOOOO ) Except for that one corner seal because the port was to big.
So yes rotories will hold up to reving as long as you dont detonate or over heat... Your trying to tell me I cant but I can prove you wrong...You guys sound like a lefties ( political ) unwiling to listen to reason. I already said you dont need that stuff for drag racing. And if the port was smaller up top to not break the corner seal then it would last as long as a stock port engine as long as not raced.
Nobody has an argument here. I know this particular port was to big. I didnt port it. And realize that I dont give a **** if it lasted me less than 10k miles comprende?
And nobody is even knowledgable enoughf to tell me if solid corner seals will work but you can tell me that I cannot rev a rotory and that im stupid for trying to race it or some ****.
Some of you guys are worse than the miata forum members
Morons. This is my engine. When you drag 1/4 and do experimental stuff you really dont need all the clearancing and balancing ****. How many times will I have to say this...My friends motor with just about the same port is still going strong after 1 year. He constintly hits 12k
NZ Conv whats up ??? How many engines have you rebuilt ? I reved my engine to the limiter for 5 seconds ask nitronick!!! Right after that I took apart the engine and guess what ? clean as a wistle. No chatter , no nothing even with heavy shity S4 rotors and unbalanced S5 flywheel ( OHH NOOOO ) Except for that one corner seal because the port was to big.
So yes rotories will hold up to reving as long as you dont detonate or over heat... Your trying to tell me I cant but I can prove you wrong...You guys sound like a lefties ( political ) unwiling to listen to reason. I already said you dont need that stuff for drag racing. And if the port was smaller up top to not break the corner seal then it would last as long as a stock port engine as long as not raced.
Nobody has an argument here. I know this particular port was to big. I didnt port it. And realize that I dont give a **** if it lasted me less than 10k miles comprende?
And nobody is even knowledgable enoughf to tell me if solid corner seals will work but you can tell me that I cannot rev a rotory and that im stupid for trying to race it or some ****.
Some of you guys are worse than the miata forum members
#75
Rotary Freak
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Ok mazdaspeed7 I guess you would know from expierience and the edges did not break my corner seal. We already established that. And whats all this reving beyond 10K rpms ? You talk about flex at 10.5 and grenading at 11k but I never said I was going to spin that high did I ??? Please stop making up fabrications
Rotorygod. Thnx ,,, I try
I knew about that VW with the same port. In fact I was also going to bridge it but I figured I would really need some of those previous mods mentioned for sure. Im possitive im in the safe zone with my current setup regardless of what people say...
I have another port desin. Instead of bridging im going to drill holes for the bridge that way the bridge will not crack...The combined volume will be bigger than a streetport but slightly smaller than a bridge...I will do it with new housings but the enginen will have to go in someone elses car because I striped mine already.
Any doners ? I will install myself !!!
Rotorygod. Thnx ,,, I try
I knew about that VW with the same port. In fact I was also going to bridge it but I figured I would really need some of those previous mods mentioned for sure. Im possitive im in the safe zone with my current setup regardless of what people say...
I have another port desin. Instead of bridging im going to drill holes for the bridge that way the bridge will not crack...The combined volume will be bigger than a streetport but slightly smaller than a bridge...I will do it with new housings but the enginen will have to go in someone elses car because I striped mine already.
Any doners ? I will install myself !!!