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

Here's an easy way to remove the diffuser part of an N/A sleeve

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Old Aug 27, 2002 | 12:38 AM
  #1  
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Here's an easy way to remove the diffuser part of an N/A sleeve

Sorry if someone already had this idea; I really don't have time to search through 100's of posts to see if it is.

From what I've read, there seems to be much confusion reguarding how to "grind" these out. Well, GRIND is too literal, and if followed to the point, it'll cost you a bunch of bits/stones/sandpaper dowels. I found a WAAAY simpler way to do this if you're cheap like me, and don't want to purchase T-II sleeves. I mean, why pay for what can be had with a little work?

1 - Remove the sleeve from the housing (2 pins, one on each side of the housing; use a screw extractor and slide-hammer)

2 - lay sleeve face-down on hard surface (the big hole goes down)

3 - take a SMALL (1/2") cold-chisel and place it where the diffuser comes from the sleeve (the "root")

4 - Angle the chisel ~30 degreese (towards the roots, of course), and pound away! (tap-WHAM-tap-WHAM)

5 - use a cut-off tool and chop the "lip" of the sleeve off. (the chunk of metal that's angled upwards)

6 - take a pair of vice-grips and straighten the end of the runner out (the angle portion of what was just cut off)

There'll be so little metal left, it's a chinch to grind out with even a dremel and carbide bits!

Okay, since the people who are reading this will porbably have ported/lots of porting experience, I also have a question:

On a 13b 6-port:

On the end housings, the port is divided in 2 by a "bridge" on the rotor side of the housing. What would be the gains (if any) to grinding this flush with the runner, and tapering the port-runner divider at a ~40 degree angle (perpendicular to the port)? Essestially, combine the 5th and 6th ports into one large one (still keeping the ports separated UP TO the port).

Anyways, hope this helps. Man, I could just see some people sitting there with a die-grinder, slowly eating away at the hardened stainless diffuser.

WHaCKo
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Old Aug 27, 2002 | 11:55 AM
  #2  
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Re: Here's an easy way to remove the diffuser part of an N/A sleeve

Ok, here's an easier way...

Originally posted by black_sunshine
Sorry if someone already had this idea; I really don't have time to search through 100's of posts to see if it is.

From what I've read, there seems to be much confusion reguarding how to "grind" these out. Well, GRIND is too literal, and if followed to the point, it'll cost you a bunch of bits/stones/sandpaper dowels. I found a WAAAY simpler way to do this if you're cheap like me, and don't want to purchase T-II sleeves. I mean, why pay for what can be had with a little work?

1 - Remove the sleeve from the housing (2 pins, one on each side of the housing; use a screw extractor and slide-hammer)
Step 1 is the same in my version...

2 - lay sleeve face-down on hard surface (the big hole goes down)
Find a pair of THRASHED TII housings- will cost you almost nothing since they are not useable!!!! Repeat step 1 on these...

3 - take a SMALL (1/2") cold-chisel and place it where the diffuser comes from the sleeve (the "root")
Insert TII sleeeves into NA housings and replace pins....

4 - Angle the chisel ~30 degreese (towards the roots, of course), and pound away! (tap-WHAM-tap-WHAM)
No step 4 needed... drink a beer or somthing while the person using the OTHER method is working up a good sweat.

5 - use a cut-off tool and chop the "lip" of the sleeve off. (the chunk of metal that's angled upwards)
Step 5... Drink another beer and laugh at the person still working on theirs...

6 - take a pair of vice-grips and straighten the end of the runner out (the angle portion of what was just cut off)
More beer and chuckles... watch some football or hockey... come back out to check progress on the "other" method...

There'll be so little metal left, it's a chinch to grind out with even a dremel and carbide bits!

Okay, since the people who are reading this will porbably have ported/lots of porting experience, I also have a question:

On a 13b 6-port:

On the end housings, the port is divided in 2 by a "bridge" on the rotor side of the housing. What would be the gains (if any) to grinding this flush with the runner, and tapering the port-runner divider at a ~40 degree angle (perpendicular to the port)? Essestially, combine the 5th and 6th ports into one large one (still keeping the ports separated UP TO the port).
If I understand correctly, this is a BAD idea. The combined port volume is just TOO large, so airflow slows down too much and becomes stagnant. It wouldn't idle, and have no power up to probably 5-6k RPM. Just about like driving a big bridge port or PP.

Anyways, hope this helps. Man, I could just see some people sitting there with a die-grinder, slowly eating away at the hardened stainless diffuser.

WHaCKo
Yeah... me too. Trust me... it's MUCH easier just to swap the TII sleeve in.

Brad
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Old Aug 27, 2002 | 11:56 AM
  #3  
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Or just use tii housings! easier yet
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Old Aug 27, 2002 | 11:58 AM
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Originally posted by banzaitoyota
Or just use tii housings! easier yet
True... but harder on your bank account if you have useable housings already...

Brad
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Old Aug 27, 2002 | 12:00 PM
  #5  
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What's the point of this? I heard the diffusers are there just to dampen the exhaust pressure waves and sound
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Old Aug 27, 2002 | 12:27 PM
  #6  
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From: Ohio
Ya they do quiet, but they are kinda restrictive and get in the way when porting.
RX7 RAGTOP: come on man, not every one has junk t2 housings laying around and this post was designed to help those people. Also with reguards to combining the ports thats not that big of a deal. My friend did it and his car still idles at the stock range and still makes ok pwr in the lower end.

CJG
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Old Aug 27, 2002 | 03:03 PM
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I have one and 2 set of TII sleeves, email me with offer 30 bucks would work
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