MTREC Question?

[HBEAT]

Can anyone explain it in simple terms and what it does???

And also can u feel it when driving, like you can feel VTEC ???

cheers

[Wh1teLeopard]

You won't feel it in the same way you feel VTEC, because as far as I understand VTEC engines actually have two sets of camshafts.

When it kicks into VTEC it's actually changing to the other cams which is why the engine note changes. If they were permanently on those cams then the engine would stall at low revs.

I'm not entirely sure about MTREC, but I know it's different to VTEC.

[Mylee]

MTREC is nothing to do with VTEC.

VTEC works on oil pressure, engaging a different shape cam lobe ( but on the same shaft) at pre set engine revs.

MTREC relates to the Throttle Bodies on the Beats engine. Basically, there is a throttle body per cylinder, i.e 3. This is commonly found on motorbikes. Cars, in general, only used to have a single throttle body for the entire engine.

[old'uns]

think the principle is throttle bodies move, ie shorten, lengthen, to alter characteristics to enable 'hotter' cams to produce power at top end, but still be able to be driven around at slower speeds easily.
hazarding a guess at: long bodies for top end, short for bottom end?
engine note changes around 5 - 5.5k on ours

[Steve_M]

MTREC relates to the Throttle Bodies on the Beats engine. Basically, there is a throttle body per cylinder, i.e 3. This is commonly found on motorbikes. Cars, in general, only used to have a single throttle body for the entire engine.

Thats it, nothing changes or moves. its just the fact that it has one throttle butterfly per cylinder.

[old'uns]

ahhh..live & learn

[Bruce]

Many points:

1. VTEC removes the need for the engine designer to decide between optimising for either top-end power or low-end torque and (I think) efficiency and smoothness. VTEC optimises both the bottom and top ends of the rev range.

2. VTEC does not need two separate camshafts. My old '93 Civic ESi had a single camshaft with a VTEC system. The brochure reckoned this single cam layout was a more fuel-efficient system than that of the twin cams in the VTi. It was a hell of an engine, capable of pulling from 750rpm to 7500rpm, with 8.7sec 0-60, and 43mpg.

3. I heard a while back that Honda, since introducing the VTEC system to the world about 20 years ago, have never heard of such a system breaking, despite several million engines including it...

4. MTREC basically gives a quicker response to changes in throttle pedal changes, because the air/fuel mixture does not have to take all that time it takes to go through a 3-way pipe splitter before entering the cylinder.

5. I've only heard of an equivalent to MTREC being used in the 2003 BMW M5, and err.... the '94 McLaren F1 road car, at $1m. I wouldn't be surprised to hear if bikes use one throttle valve per cylinder, but what other cars have this?

Bruce