FC3Sdrift

iTrader: (5)

Im jut asking cuz, i have this amazing built up j spec S5 TII engine has ran awesome since i got it, dynoed 361whp 309ft-lbs, came wih tons of top quality parts on it

anyways i tore it apart to freshen it up since i'd put almost 14k miles on it,
it had 3mm seals!!!! small port job, 7or 8 window rear main bearing, and the rotor tips have been clearanced

Im just wondering how high can this thing rev safely???

im planning on using RA 3mm super seals if it makes any differance

apexhittinbull

iTrader: (21)

hm.. I meant to go to 2nd Gen parts for sale but your thread caught my eye.
Apex seal thickness isn't the greatest variable in revvable engine, least from what I know.

What matters the most is the perfect weight symmetery between two rotors (rotating mass).

Hope this helps.

BTW, I think 8k is high enough for Turbo rotary with good map.
If you're into extreme porting, then yes super balance them out for 10K heaven.

FC3Sdrift

iTrader: (5)

id be happy knowing i can rev to 8-8500rpm safely on a daily basis

just to make sure we'e on the same page im talkin about clearancing the tips of the rotors by the corner seals

farberio

iTrader: (7)

Your fine for 8 to 8500 on stock rotors as long as its not there far a long time. You will be fine.

Post up a pic of the rotors if you have them.

FC3Sdrift

iTrader: (5)

i can't get a good picture of the machining with my camera you can sort of make it out in this picture.still in the process of cleaning the rotors



apex seal groove

Turbo II Rotor

iTrader: (2)

RPM's mean nothing if you don't know where your engine makes power. Sure you could build an engine to rev to 14k but when you are making less power at that RPM than you would after an up shift you are making less average HP and therefore not operating at peak efficiency.

FC3Sdrift

iTrader: (5)

hahaha ^^ i know , im not a newb wanting to be able to say he can rev to 10k, I just noticed on my rotors they had the tips clearanced. Im pretty much just trying to learn what the purpose of clearancing them is and what gains i will have by having that done, I can say that my irons look brand new, like a sheet of glass.

i would never rev past 7000 in 2nd-4th gear, incase it did any damage to the motor lol

even on the dyno it was still makin power but i let off at 7k hahaha



im getting the pineapple racing medium streetport template, so i would think i would have no problems making power to 8k, compared to the basically cleaned up stock port job thats in there, its like a hair bigger than stock

scathcart

I think you're a little confused. High-rpm rotor clearancing, aside from the bearing clearances, is a machining process that occurs in two places:

- The sides of the rotor. After the rotor housing width is determined, and width of the gear protusion to rotor housing land is measured, and machined to 0.010" less than the smallest measured rotor housing width. The sides of the rotor are then machined so that they are 0.055" less than the rotor/land protusion. Many rotors have this clearance from the factory, others do not.

- The faces of the rotor, roughly halfway between the combustion chamber pocket and the rotor tip. This clearance should be roughly 0.010" on a stock motor, 0.015" on a high revving motor, measured with a feeler gauge with a side plate and rotor housing mocked up. The rotor face must be machined completely parallel to the face.

Your rotors do not seem to show any machining marks to indicate either have been performed. It would appear that your rotors have merely been machined for 3mm seals, and then had the seal slots chamfered to reduce stress risers, likely with a piece of sandpaper.

3mm seals produce a signifcant amount more housing chatter at a lower rpm than 2mm seals, so this "mod" would have decreased the mechanical redline. I would not rev the engine higher than 8000 with stock seal clearances or rotor housing chatter will have a significant impact on your rotor housings.

If you increase the apex seal slot clearance, you will get better sealing at higher rpm with less chatter, since the the combustion chamber gases will provide a higher sealing pressure on the underside of the seal, however apex seal and rotor housing wear will be significantly increased.

FC3Sdrift

iTrader: (5)

that wasnt the gear side of the rotor , would that be why there is machining lines to the whole side with the gear on both rotors?,i wasnt sure if they are normally like that or what, there's only a hair taken off the tips there

from all the stuff i've read on here while researching, i read the japanese have a different way of doin it, where they machine just by the corner seals,
this is a turbo motor, machining from the combustion face seems alittle extreme

j9fd3s

iTrader: (3)

if you look at rx8 rotors, or newer FD rotors they have the cut in them. its very hard to see in pics

you rotors are normal, in fact if anything the tip is hitting the side housing where its shiny

FC3Sdrift

iTrader: (5)

how would it leave identical marks on the tips with the machining facing the same way even though the rotors face opposite direction in the engine , and yet not leave a single scratch or groove on my irons, they look like they were just lapped.

the gear side where it looks machined only has a bit near the tip taken off

i can see them in person and its quite obvious they arent just normal rotors, i have set of plain s5 TII rotors i can take some side by side pictures

FC3Sdrift

iTrader: (5)

if you're talking about the machined spot on the gear , the other rotor has more off it, looks more even

j9fd3s

iTrader: (3)

see how its shiny right at the tip? shiny = contact with side housing

http://www.mazdatrix.com/8pics/8engine/rotor2.jpg

http://www.mazdatrix.com/8pics/8engine/rotor1.jpg

its very hard to see in the pic, but that's an rx8 rotor. there is a circular cut outside of the rotor oil seals, so the rotor is narrower on its outer periphery. this is needed on a high rpm engine, like the rx8, because the E shaft flexes.

the thickness @ the rotor gear and land is a different measurement, and in general would be the same on a high rpm engine, as its near the center, and isn't as effected by stuff moving around.

FC3Sdrift

iTrader: (5)

i just checked all the tips, what are the chances all six tips wore to an even 3.1315" im gonna go get one of the stock rotors from my dads tomorrow and i can compare measurements

scathcart

Stock, the rotor housings are machined to be 80 mm wide, or 3.1496 inches.

The rotors, from the factory, at the land, should be 0.010 less, so 3.1396 inches.

The land protrusion should be 0.0055" per side, so a stock rotor should measure 3.1396-(2 x 0.0055") = 3.1286" at the tips, where you have taken your measurement.

Yours are wider than this, wider than should be considered stock.

A side clearanced rotor would be cut to provide an additional 0.005" of side clearance, so 3.1236" wide. Yours are 0.008" too wide too be considered properly clearanced. They are technically 0.003" too wide for a stock build, which would explain the shiny corner seal areas.

You have factory rotors, with factory machine lines, with a 3mm seal cut into them.

FC3Sdrift

iTrader: (5)

either way i have a spark retard rev limiter is at 7500, but it has went up to 8000 before in first and i was all worried i might have over revved it ,
i just like to know the limitations of my engine once i get it rebuild and with the streetport and then megasquirt i wouldnt mind being able to rev to 8000 on a regular basis, i building the motor with to do alot of time attack and autox






i read in a few threads where people are saying the japanese do it the gay way and do it by the corner seals

my motor was built by one of the Tom's racing performance shops in japan back in the day,

FC3Sdrift

iTrader: (5)

hahaha wow ..sorry that is horrible grammer lol, i just finished my 5:30 am - 1:45pm shift

Nick_d_TII

iTrader: (6)

I don't know about the clearancing or anything, but Here is a cut and paste from the fsm that is for a 1987 rx7.

Notice it says width(apex) is 3.142-3.144