Its Only 1.3 Liters - Page 2

TKMR2 · 08-26-2006, 04:27 PM

5 of my friends currently own RX7's all but one of them has had 2 or more all of which had well over 100k on the original engine. I won't arguew that they don't last as long as piston engines but 50-60k? give me a ****ing break. The only way i see that happening would caused by some dumbass improprly modding their car.

TomsMR2 · 08-26-2006, 04:51 PM

you have 4 friends with 100K+ FD's on original engines?

killer2 · 08-26-2006, 08:27 PM

also one problem that the Wankle had that also is a concern in pistons but not as much is the fact that people dont wait till they warm up to normal operating to take them over 2500 rmp. I LOVE MY ROTARIES.

bryanf · 08-26-2006, 08:39 PM

Remember when talking about events per revolution that the rotor turns one time for every 3 turns of the crank.

imweip · 08-26-2006, 09:24 PM

I just read the howstuffworks.com explanation on rotary engines... and my head gonna splode. So complex, yet simple.

Raptor13x · 08-26-2006, 09:37 PM

Quote:

Originally Posted by payne171

As I understand it, the fd problems were as follows:
A. Rotaries can't take detonation. One good ping and the Apex Seal will blow(I once heard the apex seals described as the rotary version of a piston ring).
B. In an effort to save weight, mazda installed too small of a radiator, especially for a delicate engine.
C. Most importantly, the ECU does not adapt to intake/exhaust mods. Considering that these are often some of the first mods people make to a sports car...BOOOM!

Yes, apex seals are the piston rings of rotary engines. The radiator is one of the biggest problems, as you mentioned, and the ECU is absolute garbage.

TKMR2 · 08-27-2006, 07:28 PM

2 of them have FD's with over 100k on the engine of them is currently undergoing a rebuild the other is still running. all I'm saying is that rotaries are not as bad as people make them out to be.

payne171 · 08-27-2006, 10:01 PM

I wish I could remember which issue it was, but sport compact car had a pretty good explanation of why you should multiply a rotary's displacement by 2.5 for the piston engine equivalent. I believe it measured the amount of air that traveled through the engine per combustion and compared that to a 4 cylinder. If both engines were at the same volumetric efficiency, the rotary moved 2.5 times the air per crankshaft rotation that the piston engine did. The reason you often see the 2 times estimate is probably because the extra half is wasted by the fact that the wankel has seen millions of hours less of R&D. Still, 240hp from a 3.25l engine seems about right for a street car.

Raptor13x · 08-29-2006, 01:42 AM

2.5 is a little excessive. It doesn't have the torque that a 3.25L engine would produce. A 2.6L is more accurate in comparison to piston engines.

payne171 · 09-04-2006, 10:14 AM

No, it doesn't. But how about if you gave it the millions of extra r&d hours the otto cycle has had? The x2.5 is a scientific conversion rate. The real-world conversion rate is definitely more like x2. It still has potential to be a really good sports car engine if mazda worked on developing its high revving potential. With no reciprocating parts, a rotary has the potential to rev a lot higher than a conventional piston engine.

Enthalpy · 09-04-2006, 10:31 AM

Rotaries use the otto cycle as well as piston engines. The thermodynamic cycle is identical in both engines.

payne171 · 09-05-2006, 07:46 PM

Right, 4-stroke is 4-stroke whether with pistons or with three-sided wankelly thingies.

I knew that, but I guess I lost it in the transmission between brain and fingers. Just the same, thank you for the correction.

Enthalpy · 09-06-2006, 12:13 AM

I'm anal retentive. I let it show too much sometimes. Sorry about that.

payne171 · 09-06-2006, 07:49 PM

No apologies necessary.

Ncturnal · 09-06-2006, 09:48 PM

Quote:

Originally Posted by ZMR2

MY friend has an FD, and man, I love the sound of that car

They sound like a weed-eater.

HighSpeedScene · 12-16-2006, 01:53 AM

I want someone to explain to me the concept of a wankel motor having no reciprocating parts...

Jay-Spec1 · 12-16-2006, 06:48 AM

The wankel motor has no parts at all the move up stop and then go down, like our piston motors.

Gairloch · 12-18-2006, 10:43 PM

Quote:

Originally Posted by HighSpeedScene

I want someone to explain to me the concept of a wankel motor having no reciprocating parts...

http://auto.howstuffworks.com/rotary-engine.htm

That site is the shiznit.

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08-26-2006, 04:27 PM	#21 (permalink)
TKMR2 Biff Tannen Join Date: Oct 2005 Location: Las Vegas, NV Posts: 397 Thanks: 11 Thanked 3 Times in 3 Posts My Google Map iTrader Rating: (0/0% )	5 of my friends currently own RX7's all but one of them has had 2 or more all of which had well over 100k on the original engine. I won't arguew that they don't last as long as piston engines but 50-60k? give me a ****ing break. The only way i see that happening would caused by some dumbass improprly modding their car.

08-26-2006, 04:51 PM	#22 (permalink)
TomsMR2 Still not heraldo. Join Date: Feb 2005 Location: Pineapple under the sea Posts: 4,911 Thanks: 18 Thanked 406 Times in 303 Posts Blog Entries: 1 iTrader Rating: (4/100% )	you have 4 friends with 100K+ FD's on original engines?

08-26-2006, 08:27 PM	#23 (permalink)
killer2 TSCNM Join Date: Apr 2006 Location: Albuquerque, NM Posts: 140 Thanks: 0 Thanked 1 Time in 1 Post iTrader Rating: (2/100% )	also one problem that the Wankle had that also is a concern in pistons but not as much is the fact that people dont wait till they warm up to normal operating to take them over 2500 rmp. I LOVE MY ROTARIES.

08-26-2006, 08:39 PM	#24 (permalink)
bryanf Some Skills Join Date: Mar 2005 Location: Atlanta Posts: 66 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	Remember when talking about events per revolution that the rotor turns one time for every 3 turns of the crank.

08-26-2006, 09:24 PM	#25 (permalink)
imweip Devil's Advocate for Hire Join Date: May 2006 Location: Orlando, FL Posts: 795 Thanks: 5 Thanked 8 Times in 8 Posts My Google Map iTrader Rating: (1/100% )	I just read the howstuffworks.com explanation on rotary engines... and my head gonna splode. So complex, yet simple.

08-27-2006, 07:28 PM	#27 (permalink)
TKMR2 Biff Tannen Join Date: Oct 2005 Location: Las Vegas, NV Posts: 397 Thanks: 11 Thanked 3 Times in 3 Posts My Google Map iTrader Rating: (0/0% )	2 of them have FD's with over 100k on the engine of them is currently undergoing a rebuild the other is still running. all I'm saying is that rotaries are not as bad as people make them out to be.

08-27-2006, 10:01 PM	#28 (permalink)
payne171 No Skills Join Date: Jul 2006 Posts: 16 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	I wish I could remember which issue it was, but sport compact car had a pretty good explanation of why you should multiply a rotary's displacement by 2.5 for the piston engine equivalent. I believe it measured the amount of air that traveled through the engine per combustion and compared that to a 4 cylinder. If both engines were at the same volumetric efficiency, the rotary moved 2.5 times the air per crankshaft rotation that the piston engine did. The reason you often see the 2 times estimate is probably because the extra half is wasted by the fact that the wankel has seen millions of hours less of R&D. Still, 240hp from a 3.25l engine seems about right for a street car.

08-29-2006, 01:42 AM	#29 (permalink)
Raptor13x Legendary Join Date: Apr 2006 Location: Farmington Hills, MI Posts: 3,997 Thanks: 7 Thanked 44 Times in 37 Posts My Google Map iTrader Rating: (5/100% )	2.5 is a little excessive. It doesn't have the torque that a 3.25L engine would produce. A 2.6L is more accurate in comparison to piston engines.

09-04-2006, 10:14 AM	#30 (permalink)
payne171 No Skills Join Date: Jul 2006 Posts: 16 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	No, it doesn't. But how about if you gave it the millions of extra r&d hours the otto cycle has had? The x2.5 is a scientific conversion rate. The real-world conversion rate is definitely more like x2. It still has potential to be a really good sports car engine if mazda worked on developing its high revving potential. With no reciprocating parts, a rotary has the potential to rev a lot higher than a conventional piston engine.

09-04-2006, 10:31 AM	#31 (permalink)
Enthalpy EMS Harmonizer Join Date: Feb 2006 Location: Denver, CO Posts: 1,226 Thanks: 8 Thanked 55 Times in 43 Posts My Google Map iTrader Rating: (2/100% )	Rotaries use the otto cycle as well as piston engines. The thermodynamic cycle is identical in both engines.

09-05-2006, 07:46 PM	#32 (permalink)
payne171 No Skills Join Date: Jul 2006 Posts: 16 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	Right, 4-stroke is 4-stroke whether with pistons or with three-sided wankelly thingies. I knew that, but I guess I lost it in the transmission between brain and fingers. Just the same, thank you for the correction.

09-06-2006, 12:13 AM	#33 (permalink)
Enthalpy EMS Harmonizer Join Date: Feb 2006 Location: Denver, CO Posts: 1,226 Thanks: 8 Thanked 55 Times in 43 Posts My Google Map iTrader Rating: (2/100% )	I'm anal retentive. I let it show too much sometimes. Sorry about that.

09-06-2006, 07:49 PM	#34 (permalink)
payne171 No Skills Join Date: Jul 2006 Posts: 16 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	No apologies necessary.

12-16-2006, 01:53 AM	#36 (permalink)
HighSpeedScene Mad engine blowing skillz Join Date: Nov 2006 Location: Dallas, Texas Posts: 4 Thanks: 0 Thanked 0 Times in 0 Posts iTrader Rating: (0/0% )	I want someone to explain to me the concept of a wankel motor having no reciprocating parts...

12-16-2006, 06:48 AM	#37 (permalink)
Jay-Spec1 No Skills Join Date: Sep 2006 Posts: 149 Thanks: 6 Thanked 1 Time in 1 Post iTrader Rating: (0/0% )	The wankel motor has no parts at all the move up stop and then go down, like our piston motors.