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Peak power isn't everything. DOHC can be useful, but it's not the be-all and end-all of performance, and there are certainly reasons why an engine manufacturer would stick with SOHC (reduced costs, reduced complexity, etc) over DOHC when DOHC may not give significant advantages for the expected usage.
when SOHC is already restricted in flow by definition compared to DOHC, and then tac onto that a restrictive head for the 2L motor... is pretty ****ty
Is pretty crap torque/power under 3k rpm, as far as performance goes.
when SOHC is already restricted in flow by definition compared to DOHC, and then tac onto that a restrictive head for the 2L motor... is pretty ****ty
Is pretty crap torque/power under 3k rpm, as far as performance goes.
Since when does where the cams sit (or how many there are) have anything to do with flow?
You are aware that it is technically feasible to have 16 valves with a single camshaft? And that a well designed 8-valve head could conceivably flow better than a poorly designed 16-valve one?
Amusingly enough, Hondas (which have been DOHC 16valve for ages) are renowned for having ****ty torque...
Since when does where the cams sit (or how many there are) have anything to do with flow?
OHC will have less valve train movement than pushrods so since there are less moving parts , less friction loss due to heat = more power ! Also pushrods suffer from heat expansion more so than ohc engines
Bug_racer supports the rebellion of the euro revolution
Since when does where the cams sit (or how many there are) have anything to do with flow?
You are aware that it is technically feasible to have 16 valves with a single camshaft? And that a well designed 8-valve head could conceivably flow better than a poorly designed 16-valve one?
Amusingly enough, Hondas (which have been DOHC 16valve for ages) are renowned for having ****ty torque...
hahahahaha. You haven't seen what they rev to have you?
No offence... but have you ridden a street bike? they have bugger all torque too, but they rev to 16k. That's how they make power. Problem with an engine that doesn't flow is that it doesn't make power low, nor at high rpm either. Pretty sure the 2L trails off after about 5k rpm. As far as honda engines go (based on info i got a few years ago, and from top of my head), they run backwards, and they use different ratios of stroke and bore to all other manufacturers, and they manage to pull it off. I think there was an article about how, for their stroke length, the motors shouldn't need to/be revving that high.
A well designed engine with more cams has more control, as individual valve movements can be determined. But that'd start the topic of valve timing, and different timing at different engine loads, hence the need for mivec, vtec, vvti, etc.
hahahahaha. You haven't seen what they rev to have you?
IIRC, the S2000 revs somewhere close to 10,000rpm. Yes, I know what they rev to - and I know that revs equals power. And engines that you have to wring the neck out of all the time to get decent performance aren't everyone's cup of tea.
No offence... but have you ridden a street bike? they have bugger all torque too, but they rev to 16k. That's how they make power. Problem with an engine that doesn't flow is that it doesn't make power low, nor at high rpm either. Pretty sure the 2L trails off after about 5k rpm. As far as honda engines go (based on info i got a few years ago, and from top of my head), they run backwards, and they use different ratios of stroke and bore to all other manufacturers, and they manage to pull it off. I think there was an article about how, for their stroke length, the motors shouldn't need to/be revving that high.
Yep, I've ridden street bikes (albeit as a passenger, I don't have a bike license), and I'm well aware of the fact that they rev to around 16k. The problem with them though is that they suffer from lack of power and torque down low (but get away with it due to their light weight - 300kgs or so with a rider and a tank of fuel for a Hayabusa for instance, but they produce somewhere around 120kW at the rear wheel, meaning you end up with something like 350kW/tonne.
A well designed engine with more cams has more control, as individual valve movements can be determined. But that'd start the topic of valve timing, and different timing at different engine loads, hence the need for mivec, vtec, vvti, etc.
OHC will have less valve train movement than pushrods so since there are less moving parts , less friction loss due to heat = more power ! Also pushrods suffer from heat expansion more so than ohc engines
True, though pushrod engines tend to be smaller (in terms of height and width for V engines), easier in some ways to work with (can remove heads without having to remove cam drive chains/belts etc), have lower friction inherent in the design (though I've heard both OHC and pushrods given this benefit), and tend to weigh less than OHC engines as well. GM and Chrysler (I have to admit, they're hardly overall success stories) persist with pushrods for their V8s for packaging and simplicity reasons. Of course, they have issues with expansion of the pushrods that needs to be countered, don't rev as high, and tend not to be as finitely controllable in terms of valve timing as OHC engines
Chris (that's his username as well) on here also used to have a 2L with some headwork and all that kind of crazy stuff. Not sure of the numbers he put down but worth having a chat with him for what he did and the kind of money he spent.
Cheers,
Trent
cheers man
yer i had a full port polished head, slightly raise comp, race cam, port matched tuned length extractors in to a full system, bmc cda & a ecu chip in mine
and as much as people rag on the 2.0l i think they are great fun, mine would sit side by side with a stock xr6 turbo from 40 to 170
but on topic i would only go for a well known and provin brand BUT with out doing any other work in a N/A car i figure it to be pointless to do a chip/flash espeacally due to the cost of it
if i was you i would put that money into a set of hottuning coilovers and you will get a much better kick out of them than just a chip in a 2.0L for the money
anyways GL with your choice"s
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cheers man
yer i had a full port polished head, slightly raise comp, race cam, port matched tuned length extractors in to a full system, bmc cda & a ecu chip in mine
and as much as people rag on the 2.0l i think they are great fun, mine would sit side by side with a stock xr6 turbo from 40 to 170
but on topic i would only go for a well known and provin brand BUT with out doing any other work in a N/A car i figure it to be pointless to do a chip/flash espeacally due to the cost of it
if i was you i would put that money into a set of hottuning coilovers and you will get a much better kick out of them than just a chip in a 2.0L for the money
anyways GL with your choice"s
thanks chris im thinking about new camshaft? your thoughts on that?
then maybe bring the ecu in and then def look at handling (which i think it does great already)
2000 Golf GLE Auto - stock
Perth's slowest golf because im broke
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