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[QUOTE=henk4]Like GTI?
No, they used that acronym, Mercedes uses CDI, PSA/Ford uses HDI or TDCI, and BMW simply "d". The only difference between the VW engines and the rest is that all use a common rail injection system, while VW is using a pump nozzle system for the time being. However they have annouced that they will also switch to Common Rail, as it is more easier to control in terms of noise and emissions.
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Ahhh, I see.
[quote]
If you (the USA) would be ready for it you could get the BMW, Mercedes and Audi V8s with mindboggling amounts of torque, which would be exactly what you describe as being your ideal engine. Prejudice about diesel engines in your country is still preventing that happening.[/quote]
Isnt our diesel gas not up to "par" with what Europe has though?
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[QUOTE=Slicks]Ahhh, I see.
Isnt our diesel gas not up to "par" with what Europe has though?[/QUOTE]
apparently from what I heard, desulpherized and cleaner diesel will be available soon over there. Again this is a matter of perception, or "chicken and egg". As long as Americans associate diesel engines with "dirty and loud" there will be no real demand for them and the oil companies will not make the investments necessary to produce the right stuff from their refineries (which are very much geared to producing gasoline in the first place)
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[QUOTE=Matra et Alpine]What ?
That has NOTHING to do with the valve drive technology :D
That's to do with CAPACITY and gearbox. NOTHING to do with vlave drivetrain per-se.
COMPRESSION ratio is the major variable that affects SFC.
Power delivery low down for trucks is spot on, needs LOTS of torque to move heavy weight easily.
But once it's into a car the advantage isnt' as clear.
OHCs in trucks will come into it's own now that better emissions are requred and more complex and variable timing is needed. Doing that in the head is "easier" -- because the in-block space for a cam is limited.
And if you want GOOD SFC as the prime choice, then go turbo-diesel :D[/QUOTE]
My point was not to disagree with you but rather, expand on the issue of push-rods.
Once again, diesel in daily cars over here makes little sense. Its far too sulphurous and dirty.
I think i started riots on UCP.
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[QUOTE=Matra et Alpine]I think you MEAN you don't liek revvy engines ?
Low revving engines can be peaky and high revving engines can be smooth.[/QUOTE]
Rather, its mostly the opposite. S2000s feel like lawn movers below 4000rpm and suddenly become a F1 car over that limit. Several other like Pontiac Lemans , which i had,(also a I4) have redline of 6500rpm and yet never feel as if they are struggling.
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[QUOTE=KnifeEdge_2K1]where's the logic in comparing a v8 that puts out 400 hp to an I4 that does 240 ?? they arnt made to be used in the same type of vehicle or the same class
with your logic it'd make sense to compare a 650cc dirt bike engine with the friggin 16 litre bugatti quad turbo, cuz you're "just comparing engines"
there's nothing about vtec that gives LOW torque at low rpms, it gives the same amount of torque at a given rpm as any other engine of the same size that;s naturally aspirated, and much higher power with more radical cam grinds at the top end, that's what vtec was made for, period.[/QUOTE]
We compared them because of push-rod vs DohC. No one's compared 'vette vs civic.
Some how, push-rods never feel 'weak' at low rpm, quite unlike some other Sohc, dohc.
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[QUOTE=sunk]
Once again, diesel in daily cars over here makes little sense. Its far too sulphurous and dirty.
I think i started riots on UCP.[/QUOTE]
you should start riots in the USA just to make cleaner diesel available.....
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[QUOTE=henk4]you should start riots in the USA just to make cleaner diesel available.....[/QUOTE]
Not expected from you, henk.:p
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[quote=sunk]We compared them because of push-rod vs DohC. No one's compared 'vette vs civic.
Some how, push-rods never feel 'weak' at low rpm, quite unlike some other Sohc, dohc.[/quote]
That's got NOTHING to do with SOHC/DOHC.
Try driving a large capaciy V8 with OHC and you'll see.
Long stroke engines provide strength at low revs.
That's it.
Logn stroke and small capaciy isn't ideal as the piston speed limits the top end revs and power.
SO long stroke engines are large bore engines are large capacity engines.
NOTHIGN to do with where the cam lives .... that's only a cost issue.
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[quote=Slicks]I dont like peaky engines. Got it?
You could call the LS7 "revvy" with its 7000RPM redline, but it certainly isnt peaky.[/quote]]SO why the "weed whaker" nonsense ?
THAT's revline ... I was just taking what you repeat continuously about revving hard.
Sounds like you dont' like peaky OR revvy :D
Dont' know ANYONE who likes peaky and having competed in a tuned Imp I can assure you you haven't even been NEAR peaky till you try a Coventry Climax tuned out to it's max on twin Webers :(
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[QUOTE=Matra et Alpine]That's got NOTHING to do with SOHC/DOHC.
Try driving a large capaciy V8 with OHC and you'll see.
Long stroke engines provide strength at low revs.
That's it.
Logn stroke and small capaciy isn't ideal as the piston speed limits the top end revs and power.
SO long stroke engines are large bore engines are large capacity engines.
NOTHIGN to do with where the cam lives .... that's only a cost issue.[/QUOTE]
may somebody should try the old in-line 6 DOHC Jaguar engine, with 106 mm stroke:)
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[QUOTE=sunk]We compared them because of push-rod vs DohC. No one's compared 'vette vs civic.
Some how, push-rods never feel 'weak' at low rpm, quite unlike some other Sohc, dohc.[/QUOTE] 1.3 litre auto escort( tappets and pushrods,) any small capacity engine wont have the torque of a 6 litre OHV V8. The LS1 here in australia with a 6 speed manual cant go up a slight rise in top because of the rediculous overdriven gears( for fuel economy) because at 110km/h its ticking over at 1500 revs, where its useable torque doesnt happen until 2500rpm. It requires 1 or 2 down changes when overtaking on the highway.Also speaking of diesel all the heavy haulage diesels cummins,detroit etc with 14 litre capacities all run ohc now, you certainly wouldnt call the weak with 1650ft/lb of torque at 1200 rpm
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[QUOTE=charged]1.3 litre auto escort( tappets and pushrods,) any small capacity engine wont have the torque of a 6 litre OHV V8. The LS1 here in australia with a 6 speed manual cant go up a slight rise in top because of the rediculous overdriven gears( for fuel economy) because at 110km/h its ticking over at 1500 revs, where its useable torque doesnt happen until 2500rpm. It requires 1 or 2 down changes when overtaking on the highway.Also speaking of diesel all the heavy haulage diesels cummins,detroit etc with 14 litre capacities all run ohc now, you certainly wouldnt call the weak with 1650ft/lb of torque at 1200 rpm[/QUOTE]
You got a point there, but we talking only about cars, pick-up trucks. Frankly, in heavy vehicles turbodiesels are the only option.
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I have one more question : Why does Honda continue with vtechs when other western manufacturers have shunned it because of limited valve architecture/upgrades ? And why doesn't Honda use it in their Indycars or F1 cars. So much for torquey v-techs.
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[QUOTE=sunk]I have one more question : Why does Honda continue with vtechs when other western manufacturers have shunned it because of limited valve architecture/upgrades ? And why doesn't Honda use it in their Indycars or F1 cars. So much for torquey v-techs.[/QUOTE]
does Toyota not use it in their VVTI engines? or BMW but calls it valvetronic? and the Porsche system? (Question marks are there because I really don't know)
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[quote=sunk]I have one more question : Why does Honda continue with vtechs when other western manufacturers have shunned it because of limited valve architecture/upgrades ? And why doesn't Honda use it in their Indycars or F1 cars. So much for torquey v-techs.[/quote]
Who has "shunned" it ?
everybody has variable valve timing adn SOME are going as far as now trygin variable compression.
What do you been by "limited" ?
It's not needed in any race series because race drivers use gears :D
Besides, not sure abotu Indy, but in F1 the FIA reg [B][FONT=ArialNarrow-Bold][COLOR=#ff00ff]
[LEFT]5.6.3 [/B][/COLOR][/FONT][FONT=ArialNarrow][COLOR=#ff00ff]Variable valve timing and variable valve lift systems are not permitted.[/LEFT]
[/COLOR][/FONT]kind of stops it :D