Discussion in 'That'll Buff Right Out' started by levit, Nov 29, 2007.
And mods here
w00t fellow rx8 owner! love the ms kit
are you on rx8club?
Of course, and I'm a super moderator on rx7club.
please educate the ignorant. Is that a cai and was it worth the trouble of throwing it on if so?
Yes it's a CAI.
Most the intakes for the RX8 do not do much. The AEM/Mazdaspeed CAI's are some of the better ones and do show improvements. Not too hard to put on either, bumper is easy to take off.
I was going to buy one of those after I graduated. Then life happened.
Man, it's crazy seeing how small that engine is. Even though I knew it was tiny, it just looks too small to be real.
EDIT: Be honest with me; how much does it really matter that the engine has 160ft*lb of torque? I can't help but think the ride quality and the handling would totally make up for that, unless you live at the dragstrip.
Rotaries are not torquey, and never will, it's the nature of the engine. Only way to get torque is turbo or a 3-rotor, but it's still nothing compared to pistons.
They make up for it, however. Good power for such a small engine, high/quick revving, etc. And because the engine is so small it's nice and light. I don't mind the lack of torque, it's still quick and a blast to drive, handles amazing.
That's what I needed to know, thanks. I'm thinking about getting one myself, but I had nightmares of being unable to pass people on the highway and crap like that.
Know anyone who wants to buy a lightly-modded '99 Passat? It makes about as much power as your car at this point, and probably more torque to boot. It does weigh a lot more, though.
Hydro lock? No bypass valve?
^Yeah that. The filter looks exposed in the first picture!
unless he goes into 2-3ft of water he wont get hydrolock...
Not necessary... The only way water travels up is if the filter is fully submerged under water. To fully submerge the filter under water I'd have to be driving in ~3 feet of standing water, and if you're doing that in an RX8 you deserve what you get.
Not only that but this is a rotary engine, not a piston. When water fills a piston engine it hydrolocks and can mess up a lot of stuff. Rotaries do not work the same way, and water would just get pushed out of the exhaust ports as the engine rotates. It might die or run really shitty, but it'll eventually just be pushed out or turned to steam and shoot the steam out of the exhaust.
It's been a long tradition in the rotary community when an engine is old and likely caked in carbon (kills rotaries unfortunately) people hook up a large vacuum line and forcefully have the engine suck in over a gallon of water. This makes the car run like utter shit until it's all out, but it essentially steam cleans the engine and breaks apart all the carbon inside.
So I'm not worried.
I should hook my friend's FC with our office cooler.
You should, it's pretty funny. The car will run like shit for a while until you can get all of the water out of the intake system, into the engine, and steamed off and out. During that time it sounds pretty gnarly and makes you think something is really wrong. Then it's perfect again.
What kind of FC does your friend have? My first rotary was an FC, 1988 GXL. I used to build motors for it every so often when I'd get bored and want to try something new. Also built motors and did repair work out of my garage for some locals.
No no no, levit, hydrolock will destroy your little rotors just as fast as a piston engine. You forget that, for the water to make it over to the exhaust side of the engine, it has to pass through the compression phase, at which point it will refuse to compress and it will push the rotor face away from the side of the housing -- and more importantly, it will push the apex on the other side of the rotor into the side of the housing, gouging it and ruining it for life.
Your only hope (and the only reason why the steam-cleaning trick works) is that the amount of water sucked in is less likely to be catastrophic, because rotaries have low compression compared to most piston engines. (which is why they can run on 87 octane, btw.)
That said, yes, you would have to drive through 3ft of standing water (or perhaps a hurricane) to get enough water in the intake to cause any kind of problems.
I've personally never heard of a rotary hydrolocking. I am sure it's possible, just not as likely.
And what do you mean by "which is why they can run on 87 octane?" The only ones that run on 87 are the 1st gen and NA 2nd gens, the 87-88 TII's (Turbo 2nd gens) say in their manual that they can run on 87 but higher is better, and any mods past stock you should be using premium, then the 89-91 TII's and all FD's (3rd gens) have 91 as a requirement. Plus the RX8's are recommended to run 91+ since they're 10:1 compression.
I've seen and done the water trick (sucking in large amounts of water to clean tired/old rotary engines) on a few occasions, and nothing bad has ever happened. I am sure hydrolocking is possible if enough is sucked in, but it is less likely than a piston engine, period.
Then we agree.
nice, I miss mine. It was the same color. Now i have a Mazdaspeed 6. Ever think of turbocharging it?
Not entirely. You made it sound like it's not that hard to hydrolock a rotary, when in fact it is. Like I said, I've never seen a rotary hydrolock even with large amounts of water sucked in.
You also said rotaries can run on 87, as if you were indicating all rotaries do, which they definitely do not. Plus there are piston engines that run on 87 too, so there was no point in that statement.
No, I have no desire to. I just want a quick, nice handling NA. I don't want to have to worry about tuning after adding a turbo, and the Greddy kit is technically supposed to be plug-n-play out of the box ready to go, but it's a huge piece of shit. All other "kits" out there would require standalone and a good tuner that knows rotaries, so I'd rather not deal with that.
It IS easy to hydrolock a rotary. Stick a garden hose in the intake and turn the spigot on. It will work just as well as on a piston engine.
I understand where you're coming from. Whereas water can accumulate inside a piston engine because the valves are at the top of the cylinder, on a rotary the water will be swept out of the cylinder by the apex seals. What I was talking about is what would happen if the engine swallowed a big gulp of water all in one shot -- if the water can't fit through the compression stage, the engine will lock, no matter what the design.
Okay, so only the earlier rotaries can run on 87, my bad. I didn't realize the geometry was flexible enough to increase the compression to the point that it needs premium to run right. However, if it does need premium to run right, then that means the compression is high enough that the risk of hydrolock is roughly on par with a piston engine.
There is no cylinder in a rotary engine.
The fact is that it would be incredibly difficult to get enough water in/through the intake for what you're describing to happen. The rotary has 3 chambers and water gets pushed through pretty quickly.
Well the TII's were Turbo, main reason they needed premium. All FD's were Twin Turbo, that's why they needed it. The RX8 is 10:1 compression, highest compression ratio rotary to date, and has aggressive ignition maps and a 9k redline, that's why it needs premium.
That doesn't change that it'd be very difficult to get enough water into a single chamber of the compression cycle to hydrolock it.