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-   -   writeup: turboing your n/a port sleeves (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/writeup-turboing-your-n-port-sleeves-986906/)

RotaryEvolution 02-08-12 05:07 PM

writeup: turboing your n/a port sleeves
 
since everyone wants turbo or free flowing n/a's and port sleeves don't grow on trees i decided to document one of the modifications to the sleeves as i was doing it. this process takes me about an hour with a good air die grinder, with a dremel figure about twice that time.

you will need at least a dremel with a cutoff wheel and carbide or porting bits
a flat tip screwdriver
long needlenose pliers
metal punch
and a vice would be helpful but not necessary


1: cut along the outside edge of the sleeve a little off the nose to remove the flat snout of the port wing.
https://desmond.imageshack.us/Himg85...jpg&res=medium

2: use pliers or screwdriver to remove the cut piece or just continuing to cut all the way through and remove it showing just the wings now in the port.
https://desmond.imageshack.us/Himg84...jpg&res=medium

3: cut a notch from the center of the port sleeve inward to use a baseline for the break to occur in the next step.
https://desmond.imageshack.us/Himg68...jpg&res=medium

4: put the sleeve into a vice and insert a flat screwdriver under the wings and pry them toward the center.
https://desmond.imageshack.us/Himg83...jpg&res=medium

5: bend the sleeves back and forth with the screwdriver and pliers until they eventually get soft and break off.
https://desmond.imageshack.us/Himg84...jpg&res=medium
https://desmond.imageshack.us/Himg64...jpg&res=medium

6: take the sleeves and cut along the bottom of the port opening where the wings used to be and the material above that cut.
https://desmond.imageshack.us/Himg63...jpg&res=medium

7: put the sleeve on a flat work place and use a hammer with punch to reform the bottom to a contour that matches the opening of the housing at the exhaust.
https://desmond.imageshack.us/Himg46...jpg&res=medium
https://desmond.imageshack.us/Himg57...jpg&res=medium

8: using your porting tools cut the existing portions out of the sleeve to smooth it out the inside.
https://desmond.imageshack.us/Himg84...jpg&res=medium
https://desmond.imageshack.us/Himg62...jpg&res=medium
https://desmond.imageshack.us/Himg56...jpg&res=medium

i've seen plenty of people do hack jobs on these and it is completely unecessary.

no_luck 02-08-12 05:08 PM

karack you always amaze me with your ingenuity and intelligence thanks for all the contributions youve made

ArmAnirx7 02-08-12 05:17 PM

How much hp would this add?

RotaryEvolution 02-08-12 05:22 PM

on an n/a from what i have seen/heard dyno result wise about 15% more over stock porting, but you may need a tunable ECU intake and exhaust mods to get that much. porting n/a intake has minimal gains over removing the diffusers but there is an increase in sharpness of exhaust note when removed.

if you can live with the noise and have supporting mods, 20 horsepower is decent compared to the minimal amount of effort doing this. leaving these in when turboing a motor is robbing yourself of potential power also.

ArmAnirx7 02-08-12 05:53 PM

Thanks! Great write up


Originally Posted by Karack (Post 10971493)
on an n/a from what i have seen/heard dyno result wise about 15% more over stock porting, but you may need a tunable ECU intake and exhaust mods to get that much. porting n/a intake has minimal gains over removing the diffusers but there is an increase in sharpness of exhaust note when removed.

if you can live with the noise and have supporting mods, 20 horsepower is decent compared to the minimal amount of effort doing this. leaving these in when turboing a motor is robbing yourself of potential power also.


fc323 02-09-12 02:05 PM

quick q.....how did u remove the port sleeves from the housing?

RotaryEvolution 02-09-12 03:04 PM

spot welded the pins and used vice grips, this is the easiest way if you have a welder. if not then a decent tapered screw and some leverage also works.

onefastrx712a 02-09-12 03:48 PM

2 Attachment(s)
looks good. I did mine when I rebuilt my motor. I didn't take mine down quite as far as yours.... I probably should have?..


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