www.RX7fb.com

Hello guys,
I really really wanted an opinion from you guys here about the apex... Whats the best type of apex an engine can use can they be handmade? We have heard theories about steel apex titanioum apex and ceramics apex to increase their resistance,well beeing, long life and of course the engine safity... This question came from a RX7 fd 830hp with a GT47 which works daily 2,0bar and go 4+bar for race drug etc. Its the strongest rotary in my country and among the best rotary in the word... The guy talks about everything he had done except what kind of apex he has on... So any ideas

There are several brands of "unbreakable" apex seals available, though stock Mazda ones are hard to beat for durability combined with how gentle they are on the housings. It's all very well putting kryptonite seals in but if they chew through the housings like a line bore then it's a false economy. An example was an engine I had which was built with what I believe were Hurleys seals... they withstood some hellish abuse but basically reamed out the housing, wore it right out. Some may work brilliantly in an application such as drag racing where the engine is under considerable stress but for only very short periods so longevity isn't necessarily an issue. Withn that said, many people use SCS, Atkins or whatever on their street cars without any obvious problems. Though nowhere near your acquaintances' 800bhp, my own 430bhp FD has run Rotary Aviation seals for the last four years because I got fed up with breaking engines, and (touch wood) it's been fine ever since

Quite a few owners in the US for street use, use Atkins seals to rebuild a 12a's because they are slightly softer and bed in better to 12a housings which have some wear.... which most do these days...... long term durability I suppose is compromised but given the mileages fb's cover these days, it isn't much of an issue.
There's no definitive answer to seals..... everyone will have had good and bad experiences with the same seals...... nature of the rotary beast.

it's interesting reading your comments about apex seals, especially sticking with the mazda stock seals.
i have been told to stick to mazda genuine parts most of the time as, well they are going to fit and are designed for the car.
aftermarket can end up letting you down, so it is understandable.

but it depends on what you want to do with the engine i suppose, ie racing or normal driving, bit of both.
i would agree that you need a seal that wouldn't chew up the rotor housing as what's the point of getting stronger seals that destroy the housing?

i know a guy i work with who replaced the apex seals in his rx8 with the ceramic apex seals, be interesting to see what the housings would be
like after a tear down.

We have an RX8 but we have trouble on its air intake....we need a big/huge air intake and we dont know what to do with it... So we havent investigate its apex thing yet... Some time if things work out well for us well put turbo on it and then well have to deal with its apex for sure...
Now for the fb we found another one which is as good as new but it has low compression so it definatly need apex as well... Its 13b (factory) the other is 12a obiouly their apex are different but which are cheeper and easiest to find and what material...and we still dont know which to chose and what to do, keep it as it is, rebuild it?
Generaly apex and air are the main trouble of our cars at the moment.

ian65 wrote:Quite a few owners in the US for street use, use Atkins seals to rebuild a 12a's because they are slightly softer and bed in better to 12a housings which have some wear.... which most do these days...... long term durability I suppose is compromised but given the mileages fb's cover these days, it isn't much of an issue.
There's no definitive answer to seals..... everyone will have had good and bad experiences with the same seals...... nature of the rotary beast.

We havent heard them...What are they made of? When we get the rb it will be among the few and the only one in our island to rebuild so we are not familiar with 12a... If they brake they just replace the engine back then...

Kitiarra wrote:

ian65 wrote:Quite a few owners in the US for street use, use Atkins seals to rebuild a 12a's because they are slightly softer and bed in better to 12a housings which have some wear.... which most do these days...... long term durability I suppose is compromised but given the mileages fb's cover these days, it isn't much of an issue.
There's no definitive answer to seals..... everyone will have had good and bad experiences with the same seals...... nature of the rotary beast.

We havent heard them...What are they made of? When we get the rb it will be among the few and the only one in our island to rebuild so we are not familiar with 12a... If they brake they just replace the engine back then...

http://www.atkinsrotary.com/

Oh my gooooood!
I love this site and it even has parts for rx8! Much cheeper than we find them here! Thank you sooooo very much!!!!!

well regarding the rx8, i had at one point thought of buying a typhoon K&n induction intake to replace the standard air box in mine.
however due to its positioning in the rx8, warm air would be sucked in rather than cold air as the cold air travelled down the pipe
situated in the front bumper area into the air box and stays cold.

the typhoon intake was sucking in warmed engine bay air. the result of this is actually less power than say a standard air filter/air box.
ok the typhoon sounded better but actually reduced power.
the guy i bought my rx8 off wanted to sell me the intake separately but after actually reading up on it i declined and used a k&n
replacement air filter in the air box. i noticed a bit more power when i changed, it just needs cleaned and re-oiled every x miles, but worked out better.

so just read up about intakes to see what others have done and what their experiences are. not sure about turbos in a rx8, it isn't quick compared
to an fd, maybe as quick as a fc turbo II, i don't mind n/a at all as i am not into speed, plus n/a engines last longer. though turbos would be fun i guess

ask ian he installed an elford turbo into one of his fb's and would be able to advise.

We have a hole on the front bumper and is right infront the air intake at the moment. We are working on several ideas for its position...