i'm not talking about the size...we already knew that.
but what's the color difference? are they coated with something?

 

Both apex seals are made of acicular cast iron. Both of them use electron beam chill hardening. The difference is with the way this process is performed on the new seals as opposed to the old seals. The new process makes the hardened portion of the seal extend deeper than the older seals. In this process a high temperature electron beam melts the tip and then it is rapidly cooled which causes it to crystallize into carbide. With the new process extending farther into the seal, the seal heats up more over a larger area which discolors it compared to the older seals. Look closely at the color variation near the outsides vs the center. It's different just like heating on an exhaust pipe.

 

you can always count on fred
thanks.

 

The RX8 seal looks like its zinc plated, I do this at work.

 

i thought it looked like it too, but i wanted to ask... now we know

 

 

I'll tell you one thing, I definitely don't see the renesis getting any where near 200,000 miles like the older 13b could get with those shorter seals. Damn that Renesis seal looks as tall as the used seals I pulled out of my S5 block with 75k on them. I wonder at what mileage will these seals start flipping out the rotor grooves?

 

they're taller than the top section of the old 3-piece seals. why would they fall out, unless your rotors are out of spec?

they're smaller, lighter, and seal better at high rpm's. they were designed for the renesis motor, and work perfectly for the renesis motor. i don't think you'll need to worry about them wearing themselves down. the apex seal doesn't wear all that much.

 

Well bigger is always better.....right?

 

They still are going to wear, the thing I'm talking about is the clearance from the rotors edge to the housing. That small gap is what's going to cause them to flip out when the mileage goes up since the seal won't have as much support from the rotor grooves. It will be really interesting to see how long they will hold up.

 

i don't think we're gonna see any problems like that. it's the side seals that take the beating in the renesis engines. i've had to replace most of them on almost every rebuild (6) i've done so far.

 

I would emagine they would be stonger than the old seals. If you think about how easy it is to break a pencil that is full lenth and then try the same thing but with one that is half it's size it is much harder to break. Just my very uneducated guess

 

if you're using that train of thought, it would be a skinnier pencil, and easier to break.

BUT--the same amount of seal is exposed, so as far as detonation is concerned, it's the same thing. unless the renesis seals are actually stronger. i don't know if the hardening thing is more for wear with the rotors or what. fred would be able to answer that a lot better than i could.

 

Slightly off topic but what's been killing those Renesis engines you've been rebuilding? Were these turbo charged from the Greddy kit or is it the excessive carbon build-up on the Automatic models? Before that car ever came out I predicted that these engines could easily blow due to the extra stress added to the thinner side seals from that side exhaust.

 

a couple guys just wanted to dick around and try to get some more power.

one dood forgot to fill the oil after an oil change (that one was EXPENSIVE!!!)
and 2 guys detonated with the greedy turbo kit. one of those is going to end up in court because the car was sent to a shop to get the turbo, install it, and tune it, and it came back with 2 busted apex seals. i would have kicked someone's *** over that one!