Lazy or Revvy engines?

Lazy or Revvy engines?

Author
Discussion

J400GED

Original Poster:

1,202 posts

236 months

Thursday 23rd October 2014
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Today at work I had a light hearted discussion regarding whether an engine is Lazy or Revvy, i.e. how some cars sit at higher revs than others at a given speed in a given gear, e.g. my Esprit turbo in 5th gear at 70mph would sit at 3,000 rpm give or take. So I was wondering what revs would one expect to see in 3rd 4th and 5th gears at 10mph increments from 30 to 80 (obviously where it is legal to do such a speed)
The reason for this is my argument earlier today was that a Chimaera has a "lazy" engine, but I would like to back up my side of the argument with real data rather than just winging it.
Does that make sense?

Any info would be much appreciated.

Cheers,

Ged

Sardonicus

18,928 posts

220 months

Thursday 23rd October 2014
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Lazy unless ..........

J400GED

Original Poster:

1,202 posts

236 months

Thursday 23rd October 2014
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??? confused

Bluebottle

3,498 posts

239 months

Thursday 23rd October 2014
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Having a lazy engine or not, has eff all to do with what speed you doing at what rpm!
its a term used to define how responsive the engine is to the loud pedal...a lot of v8 engines are slow to pick up rpms from tick over, and the RV8 is now exception. However, it can be made to be extremely responsive with the right mods, i.e. lightened and dynamically balanced internal component parts (incl. clutch and flywheel) mostly, and also fuel/ignition tuning.

SILICONEKID345HP

14,997 posts

230 months

Thursday 23rd October 2014
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I think the v8 seems to run out of steam after 100mph ,the fun seems to be running up the gears to around that speed .

Is it a v8 characteristic ? The higher revving engines seem to be better at higher speeds .

The speed six will loose until it picks up the revs then should easily catch up and then move away from the old v8 .

J400GED

Original Poster:

1,202 posts

236 months

Friday 24th October 2014
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Bluebottle said:
Having a lazy engine or not, has eff all to do with what speed you doing at what rpm!
its a term used to define how responsive the engine is to the loud pedal...a lot of v8 engines are slow to pick up rpms from tick over, and the RV8 is now exception. However, it can be made to be extremely responsive with the right mods, i.e. lightened and dynamically balanced internal component parts (incl. clutch and flywheel) mostly, and also fuel/ignition tuning.
All right Bluebottle calm down, I only asked if people had an idea what sort of speed a Chimaera would likely to be doing with what revs in a certain gear! I didn't come on here for you to be swearing at me and then patronising me all in one post!!


J400GED

Original Poster:

1,202 posts

236 months

Friday 24th October 2014
quotequote all
SILICONEKID345HP said:
I think the v8 seems to run out of steam after 100mph ,the fun seems to be running up the gears to around that speed .

Is it a v8 characteristic ? The higher revving engines seem to be better at higher speeds .

The speed six will loose until it picks up the revs then should easily catch up and then move away from the old v8 .
Thanks SILICONEKID345HP, but would you have any revs/speed/gear info that could pass on?

ChilliWhizz

11,990 posts

160 months

Friday 24th October 2014
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SILICONEKID345HP said:
I think the v8 seems to run out of steam after 100mph
Still only got the single throttle body then Daz whistle



Goaty Bill 2

3,393 posts

118 months

Friday 24th October 2014
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SILICONEKID345HP said:
I think the v8 seems to run out of steam after 100mph ,the fun seems to be running up the gears to around that speed .

Is it a v8 characteristic ? The higher revving engines seem to be better at higher speeds .

The speed six will loose until it picks up the revs then should easily catch up and then move away from the old v8 .
It's a characteristic of relatively standard RV8s in my experience and opinion.
My old 454 ci BBC (in no way 'standard') revved like a 2 stroke motorcycle, and some of the heavily modified small block powered cars I knew were even quicker up the revs.

It's also a fact, as I have always understood it, that torque is great but once you are talking about speed (as compared to initial acceleration), you need horses as well.
Naturally aspirated RV8s are always a relatively low on horse power for their size when compared to a lot of other more modern V8s.
Bloody awful cylinder head / port design probably being the biggest culprit there.

ChilliWhizz

11,990 posts

160 months

Friday 24th October 2014
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Ged, I'll keep an eye on it, should be out in beastie over the weekend....

J400GED

Original Poster:

1,202 posts

236 months

Friday 24th October 2014
quotequote all
ChilliWhizz said:
Ged, I'll keep an eye on it, should be out in beastie over the weekend....
Cheers Chilli, I only asked a simple question for some simple data and all I get is everyone's opinions. Even Lord Blackadder didn't have this much trouble teaching Baldrick how to count. hehe

RichardD

3,560 posts

244 months

Friday 24th October 2014
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I have a graph of speed vs revs in gears, so if you send me a PM I'll email you it smile.

(As pointed out I think this issue is more involved, such as what would a TVR be like with a BBC engine that had a lightened flywheel but was running a six speed gearbox with a top gear that meant very low rpm at motorway cruising speed. Wouldn't it be revvy and lazy?)

sgrimshaw

7,311 posts

249 months

Friday 24th October 2014
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SILICONEKID345HP said:
I think the v8 seems to run out of steam after 100mph ,the fun seems to be running up the gears to around that speed .

Is it a v8 characteristic ? The higher revving engines seem to be better at higher speeds .

The speed six will loose until it picks up the revs then should easily catch up and then move away from the old v8 .
Mine screams through 100 in third and keeps going like hell until I lift off.

It only runs out of steam (in any gear) when it hits the rev limiter biggrin

....... but it ain't standard wink


J400GED

Original Poster:

1,202 posts

236 months

Friday 24th October 2014
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Thanks all for your inputs, I now have the information I was after. smile

FlipFlopGriff

7,144 posts

246 months

Friday 24th October 2014
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My Griff sits at 3,000 revs at 70mph but this is due to the 3.73 diff. If I changed it for a standard diff it should be 80+ at 3,000 but I'd lose the acceleration and gain some top end speed.
FFG