Does the 1ZZ need the EGR?

[AndrewMason]

Not sure if this is the right place but this forum is possibly where the knowledge is.

Hopefully this is not too stupid a question but...

Lots of talk on the PFL cat going west and killing the engine via the exhaust gas recirc valve. If this is the route then wouldn't it be a quick fix to fix the EGR shut? What is the downside - I believe it is designed to allow re-burn of exhaust during constant rpm so for most driving/performance no difference. Guess will be some reduction in mpg, can this be quantified?

Thanks.

[loadswine]

There is no EGR valve on the Roadster engine. Valve overlap is used for exhaust scavenging, so no chance of an EGR delete I'm afraid.

[dcod]

EGR appears to be done via the timing.

At medium load, the timing is in such a specific state that increased overlap increases internal EGR for pumping loss elimination. The effect being better fuel economy and improved emmision control.

 m http://www.mr2.com/files/mr2/techinfo/R ... S2zz-6.pdf m

[loadswine]

Yep, that's pretty much what I said, valve timing.

[dcod]

Yep, that's pretty much what I said, valve timing.

Indeed, sorry.