2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

vtec 4 rotors

Thread Tools
 
Search this Thread
 
Old Jun 6, 2003 | 04:13 PM
  #1  
Kellen66's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Jun 2003
Posts: 15
Likes: 0
From: Jomama
vtec 4 rotors

I was thinking it would be nice to have streetports and peripheral ports on the same engine. There would be a seperate throttle body for each port (6) and there would be some type of oil pressure solenoid that would open or close the peripherals. The hardest part would be locating the "valve" that will open the ports because I would think that it would be best to make it as close to the inner part of the housing as possible. Do you think if you made it on the outside of the housing, and thus when it was closed had a "pocket" of air, that would mess up something. I think it might compress some air into that pocket as the volume decreases, however then it would just come out in the next chamber. Any and all insight appreciated.
Reply
Old Jun 6, 2003 | 04:48 PM
  #2  
poor college student's Avatar
Red Mist
Tenured Member 10 Years
 
Joined: Feb 2002
Posts: 1,420
Likes: 0
From: UCLA
how would you fit 6 throttle bodies???
Reply
Old Jun 6, 2003 | 04:56 PM
  #3  
Kellen66's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Jun 2003
Posts: 15
Likes: 0
From: Jomama
i dont know, they could be small, doesnt really matter about the 6 tho i was just rambling

focus!!!
Reply
Old Jun 6, 2003 | 05:39 PM
  #4  
BDoty311's Avatar
88 AE
Tenured Member 15 Years
 
Joined: Mar 2002
Posts: 2,865
Likes: 0
From: N/A
So only a few rotors would work at once? Sounds like a waste to me. Could you imagine all of the throttle cables?
Reply
Old Jun 6, 2003 | 07:17 PM
  #5  
Kellen66's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Jun 2003
Posts: 15
Likes: 0
From: Jomama
no theres still 2 rotors, its like vtec, at low rpm it uses the street port, at high it uses the street port and the peripheral port
Reply
Old Jun 6, 2003 | 07:39 PM
  #6  
Scott 89t2's Avatar
SOLD THE RX-7!
Tenured Member 10 Years
 
Joined: Mar 2001
Posts: 7,451
Likes: 0
From: Vancouver, BC, Canada
that's what 5/6 ports are for... mazda came up with the idea way before honda did.

it's the exact same thing. bigger cam at higher RPM.
Reply
Old Jun 6, 2003 | 07:40 PM
  #7  
Kellen66's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Jun 2003
Posts: 15
Likes: 0
From: Jomama
yea it is, but the peripheral would be way more effective.... I just want feedback on implementing this.
Reply
Old Jun 6, 2003 | 07:40 PM
  #8  
Scott 89t2's Avatar
SOLD THE RX-7!
Tenured Member 10 Years
 
Joined: Mar 2001
Posts: 7,451
Likes: 0
From: Vancouver, BC, Canada
it's been done before I think... no idea how.
Reply
Old Jun 6, 2003 | 07:43 PM
  #9  
dr0x's Avatar
pei > caek
Tenured Member 05 Years
 
Joined: May 2002
Posts: 4,643
Likes: 0
From: Mars
People have been doing this with bridgeports for a long time (not including the ITB idea, obviously).
Reply
Old Jun 6, 2003 | 07:47 PM
  #10  
BDoty311's Avatar
88 AE
Tenured Member 15 Years
 
Joined: Mar 2002
Posts: 2,865
Likes: 0
From: N/A
Oh i c, your thread is title "VTEC 4 Rotors" which made me think there would be 4 rotors, nevermind.
Reply
Old Jun 6, 2003 | 07:51 PM
  #11  
Kellen66's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Jun 2003
Posts: 15
Likes: 0
From: Jomama
what have they been doing with bridgeports? you mean the aux bridgeport thing?
just now thought about it, i guess that is kinda the same thing....I still think the full peripheral would give enough advantages over that to make it worth it tho.


srry bout that bdoty
Reply
Old Jun 6, 2003 | 10:45 PM
  #12  
Kellen66's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Jun 2003
Posts: 15
Likes: 0
From: Jomama
Little Kid: "OOOOooo please tell us your opinions and thoughts on making an "auxiliary" peripheral port."

:P
Reply
Old Jun 7, 2003 | 04:26 AM
  #13  
Blowtus's Avatar
Senior Member
Tenured Member 05 Years
 
Joined: Jun 2002
Posts: 374
Likes: 0
From: Brisbane, Australia
have a look at powervalve designs for 2 strokes... same concept.
Reply
Old Jun 7, 2003 | 08:47 AM
  #14  
Rotary Enthusiast
Tenured Member 10 Years
iTrader: (1)
 
Joined: Aug 2001
Posts: 1,271
Likes: 0
From: Atlanta.Georgia
what in the heck are you thinking?? and how long do you think this beast of a motor would last?
Reply
Old Jun 7, 2003 | 08:58 AM
  #15  
pillage6's Avatar
Rotary Enthusiast
Tenured Member 10 Years
 
Joined: Nov 2002
Posts: 1,060
Likes: 2
From: Jax, FL
Has anyone made a peripheral port motor that retained the side ports?

The manifold would be hard to make, but why isn't it feasible?
Reply
Old Jun 7, 2003 | 11:13 AM
  #16  
Kellen66's Avatar
Thread Starter
Junior Member
Tenured Member 05 Years
 
Joined: Jun 2003
Posts: 15
Likes: 0
From: Jomama
it is scoot makes them. and theres no reason it wouldnt last....
Reply
Old Jun 7, 2003 | 01:48 PM
  #17  
1987RX7guy's Avatar
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
Peripheral port motors don't make it very far into life before they pop. Probably 40k if you are lucky IF

If peri ports were good for the engine life mazda would have kept the design but they did not and instead went to side ports and now with the new renesis all ports are on the side and not on the periphery.

Peri ports are good for power yes this is true but you need to build a very strong motors to be able to go up to the RPMs where it makes power and I hear this is about 10k RPMs.


This kind of engine would not last at all maybe a couple of years at most. It would wast so much gas you would not beleive it. It would be so loud your ears would bleed if you drove agressively a lot. you will in no way be able to run cats because it will be pointless I am not sure but I think they would clog after the first couple of times you used the peri port. Not to mention your exhaust would be designed for only one of the port styles so you would lose power down low or up high any way you look at it.

Basically just leave this idea with the 8 rotor school bus and let it die out man.

Santiago

PS and also you would be spending a ton of money probably like 6-10k dollars.
Reply
Old Jun 7, 2003 | 09:19 PM
  #18  
Kai's Avatar
Kai
Rotorphile.
Tenured Member 05 Years
 
Joined: Mar 2002
Posts: 1,296
Likes: 0
From: Richmond/NoVA
Originally posted by 1987RX7guy
If peri ports were good for the engine life mazda would have kept the design but they did not and instead went to side ports and now with the new renesis all ports are on the side and not on the periphery.
I was under the impression that they did that for emissions and efficiency reasons.
Reply
Old Jun 7, 2003 | 09:24 PM
  #19  
1987RX7guy's Avatar
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
Well yes that is also a factor. But it has always been my understanding that peri ports will not last long. I am no authority though. Please ask someone with the proper experience for a good oppinion on this. I am just repeating what I have read on some websites and what most people agree on this forum. If you read up on the early rotary engines in the cosmo(I think) they were peri port designed and would fail withing 50k miles or so. I read this in one of the books Wankel7 lent me.

Santiago
Reply
Old Jun 7, 2003 | 09:53 PM
  #20  
darkwaveboi's Avatar
Need donor car in Fairfax
Tenured Member 05 Years
 
Joined: Nov 2001
Posts: 1,759
Likes: 0
From: Northern Virginia
the 787b was a 4 rotor peripheral port engine. and from my understanding it was one of the most reliable cars in the race. Who knows if he's talking about for street use or the track??
Reply
Old Jun 7, 2003 | 10:04 PM
  #21  
1987RX7guy's Avatar
Eat Rice Don't Drive it.
Tenured Member: 20 Years
iTrader: (3)
 
Joined: Nov 2002
Posts: 12,752
Likes: 1
From: Laredo, Tx
Yes but compared to our cars it probably would not last half as long as most of our 13B's
Reply
Old Jun 7, 2003 | 10:11 PM
  #22  
darkwaveboi's Avatar
Need donor car in Fairfax
Tenured Member 05 Years
 
Joined: Nov 2001
Posts: 1,759
Likes: 0
From: Northern Virginia
Originally posted by Kai
I was under the impression that they did that for emissions and efficiency reasons.
I believe it was the most 'cost effective' way of reducing emissions...One of the key reasons the FD was discontinued was because the emissions standards were getting tighter, especially in california.

as for efficiency, i remember reading somewhere that it reduces the amount of blowby gases that find their way back into the intake in the housing.
Reply
Old Jun 7, 2003 | 10:27 PM
  #23  
bingoboy's Avatar
Lava Surfer
Tenured Member: 20 Years
 
Joined: Mar 2002
Posts: 2,354
Likes: 0
From: Kailua, HI
Originally posted by darkwaveboi
I believe it was the most 'cost effective' way of reducing emissions...One of the key reasons the FD was discontinued was because the emissions standards were getting tighter, especially in california.
umm...FD sales went straight down the toilet...i am sure if it was like a super hot selling car they would have fixed the emissions problems with it and kept it alive.
Reply
Old Jun 7, 2003 | 11:18 PM
  #24  
j9fd3s's Avatar
Moderator
Community Builder
Liked
Loved
Community Favorite
iTrader: (3)
 
Joined: Mar 2001
Posts: 31,833
Likes: 3,232
From: https://www2.mazda.com/en/100th/
we talked to koby and he says the 787b motor could have gone another 24hours, keep in mind after 24 hours everything was still in spec. the peri ports basically have little effect on reliability by themselves, the reason they live short lives is because the available housings have port timing for max power at super high revs, its totally possible to build a pp motor with lower rpm timing, nsu did it. and also until recently you HAD to use the carbon apex seals which dont last as long as the iron ones do

mike
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
jase03
3rd Generation Specific (1993-2002)
26
Sep 29, 2015 10:36 AM
stickmantijuana
20B Forum
9
Sep 22, 2015 07:39 PM
ZacMan
Build Threads
4
Sep 19, 2015 09:20 PM
Ian_D
New Member RX-7 Technical
6
Sep 6, 2015 10:38 PM




All times are GMT -5. The time now is 07:23 PM.