MATTTTNUT

What are the best apex seals for single turbos running 20+ boost? Also give me some price ranges, I know some of the carbon one's can cost up to 300 bucks a seal, how good are the hurleys? how much?

94touring

If you can stomach paying $1800, go with the cermanics. To me the best buy would be the hurley racing seals with the double springs. I just put in the 3mm hurley race seals, and man what a difference between stock. These things are so much better, and the springs won't collapse, or allow the seals to flutter at high rpms. You can buy them directly from hurley in the UK for fairly cheap, I paid about $600 from a dealer in the States. Oh can these seals will hold more boost than you will ever run.

Greg

Exactly, I got the 2mm 2 piece race seal. The ceramics are great but when you blow the seal its goodbye engine TOTALY. The ceramic seals have a way of destroying everything in their path when they break. My mechanic pulled apart a motor with ceramic seals and they destroyed everything in and around the rotor housing. Even the stock 3mm seals are great seals. But I would say if you dont need to mill your rotors out to 3 mm get the hurley 2mm seals cause if you ever blow them you wont have to scrap the rotor. You can simply send them out to get milled and install 3mm seals rather than getting the 3mm seals when you dont need them and then you have to buy a bran new rotor.

RX794

I would go with the Hurley seals, they're cheap and if your motor blows for what ever reason, they won't damage the rotor housings.

Mach2

I agree with everyone regarding the Hurley seals. They're probably the best out there that aren't too expensive(like ceramic). I don't know about them not damaging the housings though. I think if they break they'll be just as bad as any other seal. Go for the racing tip with the double springs and you'll have a very good seal.

Greg

I am not saying that they wont damage the housing but you have NOOOOO idea how bad the ceramic seals will **** your motor.

risc

Hurley's are going to chew up your housing,rotor and your turbo when they break. Flatening a spring is not the same as braking a seal, there is really no chance of other damage ocuring. If you break a ceramic seal your rotor and housing are toast but there is a chance it will be dust before it leaves the motor thus not killing the turbo.

I'm trying to decide between the Hurley long life and the double spring for the motor in my supercharged REPU. I chiped an apex seal on a MANA GSL-SE motor. I like the double spring seals, but I plan to build a motor with 3rd gen housings and internals for it so it might just be a waste. I'll problably go with the double spring ones though.

Do you order direct? Or are there any US dealers? KD?

-Dom

Greg

You can order from them direct. I got my 2mm 2 piece racing seals with springs for $300

Greg

Who said hurley is ceramic??? Ianetti is the only people I know of who makes the ceramic seal.

RX794

Anybody ever heard of the titanium made apex seals with lube coating (so that it doesn't damage the housings due to titanium's friction properties)? They're pretty cool but strictly made for a race car only! These seals could never be used on a street car because of cost and also because the coating on the apex seal doesn't last long. All I can say is that there's a certain 3 rotor "racecar" supposedly using them right now from what I heard.

XSPOWER

I'm out here in Osaka, Japan at the moment doing some research for our Subaru WRX project and meeting with friends in the Japanese tuning industry so I haven't visited the forum in awhile. Anyhow, in talking to alot of Rotary tuners, everybody is saying that the NB Apex Seals are the seals to use. The NB seals are the same seals used in the Scoot RX-7 (the periphial T51 Kai SPL red car) and many rotary tuners out here are buying them all up. In fact, theres over a 3 month back order right now. I`ve had 5 sets on order for 2 months now. The seals are about $1500 a set and they are made of some kind of steel alloy composite and they come only in a 2 piece, 2mm configuration. I believe they are double spring too. I'll you guys know about them when I recieve them.

Oh yeah, by the way the Scoot RX-7 just changed from a Hks F-Con v Pro to a Power FC.

RICE RACING

I have talked about this at length before so I will not go on too much....

I use the factory 3 piece 2mm seal because it seals the best, is lighter than 3mm 2 piece (ferrous seals). Plus it does not cause fatigue cracks in the corner seals or snap the ends of the seals cause the 3 piece design allows relative movement of the seal with far less loading as it rocks in it's slot (backwards and forwards) due to fluctuating loads caused by frictiong,gas pressure and change of swing angle's.

This is some of the reasons Mazda use 3 piece design seals in their cars, in particular the 787B 4 rotor engine (in ceramic form).

So long as the seal (metal "ferrous" based) are not subjected to thermal overloading causeing chamfering they last very very well and infact will out live the side seals by a factor of 2 to 3, by which time the engine will need to be rebuilt...for these reasons I do not waste my money on buying "expensive" seals when there is no need for them assuming the engine is set up right.

And yes I have used most types including the Iannetti seals (regarded as the best in the world) they do last well but as I said the engine needs to come apart for other wear and tear so I could not justify the expense of their seal when I do not have a problem with the factory 2mm version.

Just my experiences....

crispeed

Yours,mines and just about all the real rotary tuners out there have said that many times before. If you do your home work properly you don't need any of the fancy stuff! All you're doing is putting a bigger size fuse instead of finding the source of the problem! They all break if it's not right. I know of many people that are running 35 to 40 plus psi of boost with stock factory type apex seals and are not having any problems.
It's funny how so many of these Rotary experts only came along after the 3rd gen FD rx-7 came about!

just my opinion!!!

crispeed
87TII
9.67@141mph

soul assassin

i understand what you guys are saying about the "tuning crutch" by using bigger seals i.e. 3mm. but what about the actual sealing of the seals at low and high rpms? the hurleys advertise better sealing more vacuum and idle and better sealing high rpm. to me the sealing has nothing to do with the tuning aspect of it. someone can come over here and slap me if that made no sense.

Greg

ill be right there! just kidding. The only reason I went with the hurleys is because I know about 7 people that use them in the engines from 12a to 20b twin turbos. They have all had all good things to say about them. I also heard from alot of people that the stock 3mm seals are good also.

RICE RACING

Soul assasin, that is my point...sealing

the 3 piece 2mm seal has EXCELLENT SEALING, LOWEST FRICTION & LIGHTEST WEIGHTof the ferrous seals.

The only seal that has a lower coefficient of friction is the 2mm Iannetti seal, but it does not seal as good cause it is a two piece design.

Now none of the ferrous seals seal well when they are bowed in the middle due to excessive heat loadings causing the seal to preferentialy wear in the middle and on the leading edge, Iannetti's do not suffer nowhere near as bad from this (I tell you from personal experience)

I repeat when the (2mm 3piece factory seals are new) nothing seals better than they do on a good rotor housing. Hurleys are softer and bed in better on worn housings, Iannetti's work best on new housings.

Now again if the seals are not abused by thermal overload the stock seal will out live the other engine components quite easily.

soul assassin

so your saying i can run 1.5 bar boost with stock 3 pc 2mm seals as long as it is tuned right? the only reason i thought about going with 2 peice was because of the high boost, not for lack of tuning. so what does anyone recommend for that kind of boost level i don't know what it is in psi. the 3pc seals have to have a limit somewhere as far as boost levels go -so the 2 peice should be able to handle more boost coorect? correct me if i am wrong please. i am in the process of buying new parts for my new engine and this is going to be a major factor in my descion for apex seals. i know this might be a tad off topic but what about corner seals. i was told the best are solid ones without the rubber gasket thingie.

RICE RACING

I can only speak for my self here, I have no problem with 3 piece 2mm seal and have found them to produce the most power (due to excellent sealing) and take the greatest amount of revs (due to less friction and light weight) and be the most durable in regards to corner seal breakage because of their design.

I can send you heaps of broken solid corner seals that have fatigued with extreme use (not due to detonation) just lots of hours at thigh combustion pressures, the rubber plug expansion seal is the most durable and best sealing with lowest friction.

The only real reason for the "other" alternatives is if you need to run at the thermal limits of your engine (Iannetti for example) when you do this the rotor housings distort (I can show you this) and the side seals wear very very quickly.

If money was no issue for me I would continue to buy the Iannetti seal as it does last very long but as I said it is not the best (3 piece) design and there are other parts that wear out anyway so this is why I do not bother with them any more.

In regards to the Hurley seals, again they are softer than the Mazda which is good if you have marginal housings. As far as the higher spring rate you can do a search for this topic as I explained it before...if you run the right clearances (apex slot to seal) gas pressure does all the seal as it is meant too.

In summary if you have lots of money buy the best seal you can in terms of power out put on a healthy fresh seal I doubt that any seal will out perform the mazda 3 peice 2mm desing due to reduced friction and excellent gas seal, and in answer to your HP or boost limit well from my calculations 1000bhp on a 13B is about the strength (read pressure limit BMEP) of this seal.

I have been running them at near 600bhp for many thousands of racing kilometers and never had any problem "touch wood"

Just my thoughts.

XSPOWER

If you drag race, like most of America, the stock seals will hold up fine for most folks. The exhaust gas temperatures are high for only 9 or 10 seconds at a time, but in endurance racing like N1 or Group N racing where a race lasts for 3 hours or top speed runs like boneville where the engines are at thier thermal limits, alot of the Japanese engine builders swear by the NB seals. I'm going to meet with the engine builder for the C-west N1 car today so I'm gonna ask him some more questions about the NB Seals.

Just my .02

MATTTTNUT

NB seals?????

MikeYOX

Soul Assassin:

I noticed that on the page with your car, it mentions that you apex seals have been shot peened. Does this really help the apex seals' durability? Does anybody know if cryo treatment could help the apex seals too?

soul assassin

it makes it alot stonger i have ran 1.8 bar numerous times on accident of course with no problems.

MikeYOX

Thanks