Tim Benton

iTrader: (1)

If Rick only wants to use 3 mm in used housing, but your getting new housings, is it his opinion that 3 mm are better even in new housings as well?

Tim

rynberg

Tim, Rick will not build a motor with used housings period (other than with very special circumstances). He does recommend 3mm seals, especially with used rotors.

As I described in post #68 above, I saw a torn-down Rick motor with 50k on it with 3mm seals. Other than the very impressive dent in one rotor from massive detonation, there was very little wear to any of the housings and none of the apex seals were broken or even very worn. And that motor was driven HARD.

3mm seals may chatter or cause housing wear at extremely high rpm (above 8k rpm), but in a more typical situation, they don't seem to cause significantly more wear and they can obviously take detonation much better than 2mm seals.

I used to think 2mm seals were better but I'm definitely being convinced otherwise...

Tim Benton

iTrader: (1)

that's some good info. Who does his machining on the rotors? That's another important job when using the 3mm seals. Does he do it all in house?

Tim

rynberg

I don't know who he uses but he does outsource the rotors for machining. I could ask if you're interested, it might be a local place or it might be Rotary Performance.

FDNewbie

iTrader: (10)

That's a good idea. But it only means someone's gonna be takin extended lunch breaks or duckin out of work early to pass by the shop lol

Wow...I learn something new every day. So are 3mm seals a bad idea if you're trying to built a high revving motor? (And yes I know that means you gotta have adequate fuel, prob a 2 peice e-shaft, and a shatter shield)

Compilez

iTrader: (3)

Same here. The guy building my motor STRONGLY recomends 3mm seals.

From what I've been told by the guy building my engine, he says that the 2mm seals can't take high hp as well as the 3mm seals can. He uses Hurley Seals. He showed me an example using the corner seals for each 2 and 3mm seals.

FDNewbie

iTrader: (10)

I'm w/ you, and I've heard the same. But I wasn't referring to a high hp motor...I was referring to a high revving motor (yea I know usually the two go hand in hand), but the point is, Rynberg was saying how the 3mm chatter at higher rpms. I was curious if that meant if you're building a high revving application (say up to 10K rpm), would you actually want 2mm seals instead? Obviously there's a trade-off here...high hp resistance vs. high rpm resistance.

rebuild FD

what is the approximate cost diff between 2 and 3 mm?

rynberg

The seals aren't that much difference in price but the machining out of the rotors to run 3mm seals is about $350+.

Compilez

iTrader: (3)

Ah yes... I read that wrong.. My bad. That would be nice to know though.

rynberg

Guess what finally arrived today.....

ROTORhead93

Good luck with the whole rebuild. I'm anxious to see what numbers your car puts out when its all said and done. I might just even drop by ricks to see whats up if ya dont mind. Good luck man.

darkphantom

iTrader: (2)

just did mine on 74K with a mild port. Welcome to the club & keep us updated. IMO id go with the BNR stage 3's you still staying sequential or going non seq?

rynberg

Them's are the BNR Stage 3s....sequential.

HDP

iTrader: (2)

Simplified sequential... all new solenoids?

RX 4 Speed

hey Rynberg, and all you other gurus. Besides poor mileage, rough idle, and hot starts (please explain this to me too), what are the other symptoms that an engine is blown or has a blown seal? I just want to be aware of it, so I know when it's time for me to join the club.

Also, since my car is mostly stock (see sig for mods), would it still be adviseable to go with 3mm seals?

Mahjik

iTrader: (1)

Wow, for some reason I thought you were going non-sequential. I have no idea why I thought that though..

FDNewbie

iTrader: (10)

?? Mahjik, whatcha smokin? Tyler (like myself) is a hardcore sequential freak

rynberg

Not simplified, the car must pass both visual and sniffer emissions testing. Otherwise, I very likely would have gone with a small single turbo.



Not as hardcore as I used to be, but something like that....

rynberg

Well, I'd like to keep this thread clean of other issues....if the engine's bad, you'll know! Regarding the 3mm seals, find yourself a knowledgable and honest engine builder, tell him what you want from the motor, and listen to his advice.

jsplit

I could pass you along some videos of how my engine acted when it was blown ( seal ). It's not just hot starts, even an unexperienced ear when familliar with what a blown engine sounds like can tell the difference on startup. Another thing which one of my videos will show is poor vacuum, you can watch the vacuum on the boost gauge just bounce and shift around about 4hg's. Also the idle, if it idle's like a cam'd v8, most likely you have problems...

The first one shows the exhaust tone / note.
The second shows the cool vacuum fluctuation on the lower gauge.
The third is a startup, note how the engine sounds like its choking before it actually starts, ignore my loud *** radar detector ;p


http://www.fd3s.cc/blown/

Mahjik

iTrader: (1)

because:

I know he's been softening up.

FDNewbie

iTrader: (10)

Ahhh. Tyler = wuss. LOL

RX 4 Speed

thanks... i got a friend who's engine sounds like this already. I may have to tell him the bad news.

rynberg

I will always support and recommend running seq twins for a car that is primarily street driven. However, as my car becomes more and more setup for the track, a small single turbo setup for quick response and not ultimate top-end power, becomes more desirable...

I do not and will not recommend running non-seq twins on a primarily street-driven car. I'm not softening much on that issue at all.