I never turn my engine off at petrol stations!

[matty6660]

TREMAiNE said:

I like the part where the OP says there is also a 2.6L version after someone corrected him saying it's a 1.3!

It's hilarious seeing someone know so little after thinking they know so much. We've all been there at one stage though.

why does it say 2616cc on the log book

[otolith]

Because the DVLA disagree with Mazda on how the displacement of a wankel engine is calculated. Simple as that.

[TheAllSeeingPie]

Because the rotors form 3 combustion chambers and in use one will be combusting and the other exhausting, whereas a conventional piston only has one chamber. So the 2600cc is the total volume of 2/3rds of the available chamber space. Mazda disagree and say that each rotor = 1 piston therefore they measure 1/3rd of the available chamber space.

[Daston]

However I do like when the DVLA get it wrong...or right, my RX7 is 1299cc on the log book cheap tax

[sparks_E39]

matty6660 said:

why does it say 2616cc on the log book

It's definitely a 1.3.

[matty6660]

sparks_E39 said:

It's definitely a 1.3.

"The actual "full" displacement of a 13B is 3.9L, but that is from 1 full rotation of the 2 rotors. **But** 1 full rotation of the rotors turns the crankshaft (or properly called an "eccentric" shaft on a rotary) *3* times.

Since a piston engine rates it's displacement based on 1 rotation of the crank, Mazda follows suit and rates the rotary by 1 crank revolution... so 1/3 of 3.9L is 1.3L.

From a power output perspective it's really a 2.6L as you get twice as many "power-strokes" from a rotary then from a piston engine. This is why rotary engines are so powerful compared to its size."

https://uk.answers.yahoo.com/question/index?qid=20...