Engine & Gearbox 2.0 Petrol - Revs at 70mph

Discussion in '1st Generation (2004-2011)' started by qc2, Tuesday 27th Sep, 2016.

  1. qc2 Senior Member ★ ★ ☆ ☆ ☆

    United Kingdom quince Bromley
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    Taking the FR-V on a long run I always gasp at the economy and realising the revs are around 2,800 RPM in 6th gear cruising at 70mph. I even began to question whether I have the correct gearbox!

    Bearing in mind my 2.4 auto accord cruises around the 2,100-2,200 mark with 1 less gear, I feel I'm rightfully disappointed!

    What do others get in autos or the other petrol engines?
     
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  2. DrSam Valued Contributor ★ ★ ★ ☆ ☆

    United Kingdom Sam Birmingham
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    My Accord and FR-V is at around 2,100rpm at 70mph

    Both 2.2 Diesel
     
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  3. RobsyUK Valued Contributor ★ ★ ★ ☆ ☆

    United Kingdom Rob Milton Keynes
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    I'll check what revs my 1.8 auto is at tomorrow for you
     
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  4. SpeedyGee Administrator Staff Team

    England Speedy Birmingham
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    My Accord 2.4 6 speed sits at about 2700 or maybe 2800 at 70MPH.

    You can control economy by lighter acceleration and avoiding unnecessary braking by planning ahead.
     
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  5. BB Baboonface Valued Contributor ★ ★ ★ ☆ ☆

    United Kingdom James Chesterfield
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    Sorry, not quite on topic but is the Accord 6th gear ratio .659 like a TSX? Wonder if you could swap in such a gear in to the FR-V like folk do on the other K series boxes?

    Admittedly it would take some time of saving on fuel economy to recoup the cost of doing so, so i'll shut up and go to work...
     
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  6. qc2 Senior Member ★ ★ ☆ ☆ ☆

    United Kingdom quince Bromley
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    I'm quite surprised that the manual cruises 70 mph at 2,700 revs bearing in mind the auto does so at around 2,200-2,300. I would've expected the manual with an extra gear to cruise at the same revs at least. I thought my FR-V was revving higher due to having smaller displacement.

    I can't complain with economy in my auto accord, I'm getting 400+ miles per tank. What's puzzling me is that the manuals with their cruising 6th gear actually rev higher at 70mph. Doesn't seem logical to me.
     
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  7. SpeedyGee Administrator Staff Team

    England Speedy Birmingham
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    My CL9 still gets me 400 to a tank on petrol.
    There's more to economy than just being sat lower on the rev range.
    Also I'd rather be sat at the start of the torque band, than be cruising at lower revs where there's a flat spot.
     
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  8. Bones126 Top Contributor ★ ★ ★ ★ ☆

    England Dave Birmingham
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    Same here
     
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  9. qc2 Senior Member ★ ★ ☆ ☆ ☆

    United Kingdom quince Bromley
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    My 400 miles is pretty much all motorway. I'd expect to get more from a manual irrespective of how it revs when cruising. Just goes to show how differently the auto and manual transmissions are set up I guess. Performance and torque preferences aside I just expected that the same engine wouldn't be working harder to achieve the same cruising speed on a manual than it would the auto.
     
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  10. RobsyUK Valued Contributor ★ ★ ★ ☆ ☆

    United Kingdom Rob Milton Keynes
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    Ok at 70mph my revs are roughly 2.6k
     
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  11. SpeedyGee Administrator Staff Team

    England Speedy Birmingham
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    The gearing in an Auto has a different philosophy behind it. The final gear is like an Over Drive gear, it's not designed for quick acceleration it's designed only for cruising. Let's say you're doing bang on 70MPH and you want to pickup speed up quickly (of course you'll only be doing this on private land and not breaking the legal speed limit :Smile: ), so to give you this quick acceleration the auto will kick down into 4th and you'll get the quick pickup of speed that you want.

    In a manual the gear ratios are chosen so that you are not sat in a flat spot if you are in the correct gear for the speed you are going out. If you are in 6th gear doing 35MPH then obviously you are not in the right gear for the speed and you are labouring the engine, so you will be in a flat spot. At 70MPH in 6th you should have respectable amount of pull away should you need to.

    Do you see the difference now @qc2 ?
     
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