veilside_mazda

Im in the uk and on another forum i started a post about an rx7 gen3 and alot of people are saying that the car is a 2.6 and im sure that its a 1.3 could anyone shed some light on this and could you point me to a mazda site that states that because i know they wont believe me when i show them just the post

Thanks

Ps i sort of envy gen3 owners cause im 18 and i cant get insured on one yet

rynberg

1. Use the search function, this has been debated to death.

2. This topic does not belong in the Advanced Tech 3rd Gen section.

Mahjik

iTrader: (1)

https://www.rx7club.com/showthread.p...hreadid=269803

Evil Aviator

Many countries consider it a 2.6L engine for taxation purposes because it breathes like a 2.6L 4-stroke piston enigne. However, the displacement of the two rotor housings is 1.3L.

Snrub

iTrader: (1)

You're right it's 1.3L, but it breaths like a 2.6L.
Discussion ending proof:
http://www.geocities.com/jeffguilfoi...lacement1.html

TurboSmoke

lets not start this subject again, please.

Evil Aviator

Just as a clarification, it breathes like a 2.6L 4-stroke piston engine. It is very important to make that distinction, because it also breathes like a 1.3L 2-stroke piston engine. This is all assuming the same volumetric efficiency, of course.

LOL, this thread is an explanation and clarification, not a debate, since there really is no point in debating a tax code.

KevinK2

The simple answer is:

4-stroke piston engines dominate the auto world. Their rated displacement reflects the total air pumped in, over a complete engine cycle (2 crank revs). In this case, complete engine cycle is when all cylinders have been fired once.

Mazda wankels are also 4 stroke engines. But their rated displacement reflects the total air pumped in during just ONE crank rev.

----------

The 'one rev' mazda rating considers each housing as a cylinder, and suggests a complete engine cycle is when both housings have fired once (one rev). It ignores the fact that at any instant, 6 independent chambers (2 rotors x 3 faces) are each at varied stages of the otto cycle, just like a snapshot of a 6 cylinder piston engine.

Regarding displacement of air into the engine, automotive engineers (and a few others) understand that all 6 of these chambers will go through complete otto cycles in 3 e-shaft revs (one true engine cycle), displacing 3.9L in 3 revs. You can still just look at 2 revs (2.6L) to compare with piston engines, or one rev (1.3L) for the NSU/mazda rating.

--------

Problem is there is no proper universal method/standard for claimed engine displacement ratings, so ratings for 2-stroke scooters, v8 bentleys, and wankel rx7's are not technically consistent for direct comparison of injested air.

Jeff20B

iTrader: (13)

That's a good explanation, Kevin. I like 1.3L or 1308CC the best. Always have.

vspecpgt

i think its easiest to just count the total volume of the combustion chambers..... we've got two "cylinders" and so add the two combustion chambers for the 2 cylinders and you get 1.3 liters.... same thing if you counted 4 civic combustion chambers (4 cylinder) you'd get 1.6....

bottom line, is that they are just mad cause we have cooler motors! whoo hoo!

paximus

iTrader: (1)

rotary piston

rotary piston
rotary piston
but in the end...