What I like about Honda k20's

[Dipper]

Other than their all round awesomeness they're pretty damn good on fuel as well! Did a run today with my honda'd s2, mates supercharged exige and my bro's supercharged Elise. Starting from full tanks, we stopped to fill up and the sc Elise took £50, sc exige took £42 and my Honda a mere £36!

Nae bad at all!

- which clearly demonstrates how inefficient these blown engines are, particularly the Eaton blowers -

Interestingly have done a lot of work fueling on my engines, and it is clear the K20's have sequential fueling only at low revs, on WOT throttle or above 2500rpm it looks like they go into old fashioned batch firing.

so clearly the thing is set up for emissions, and they are not using the potential of a modern fuelling scheme for better power and torque - now there's a hint!

Or possibly how efficient the Honda is?

I can't help wondering if your engineering nous would be better out to use developing a modern engine conversion for these things. K's are long dead and the k20 has also gone the way of the dodo. As k series cars get older and cheaper i guess there will be less and less owners willing to cough up the cash to have them overhauled to your standards. Conversions are more likely to be done DIY rather than turn key as well.

Surely there must be lightweight, reliable(without opening the engine), economical and reasonably powerful modern engines that could be used rather than the usual, Honda, ford, Audi conversions? Of course the fact that the k20 can be had cheap 2nd hand is a big driving factor I guess.

Having read the vast majority of your k series spiel(and very interesting it is too), I don't think I came across a cost. If joe blogs wanted a turnkey king k what would they be looking at? Would it be on an engine exchange basis?

[Scuffers]

Interestingly have done a lot of work fueling on my engines, and it is clear the K20's have sequential fueling only at low revs, on WOT throttle or above 2500rpm it looks like they go into old fashioned batch firing.

well, you have that 100% wrong too then.

they are sequential at all times (except when in fall-back fail mode and at initial start)

[KingK_series]

Interestingly have done a lot of work fueling on my engines, and it is clear the K20's have sequential fueling only at low revs, on WOT throttle or above 2500rpm it looks like they go into old fashioned batch firing.

well, you have that 100% wrong too then.

they are sequential at all times (except when in fall-back fail mode and at initial start)

Ok I'll rephrase that - yes if you take the narrow definition of sequential as firing 4 injectors in firing sequence, that IS true, however in the sense that I had meant, that the advantage sequential firing gives when properly prepped fuel is ENTIRELY fueled into each cylinder in less time than the inlet valve is open, and the injector is not firing into static air before the inlet opens which is the same result as semisequential fueling, the Honda IS NOT fueling in the inlet valve opening alone.

IE to keep the injector small to give reasonable fuel prep at 3.5bar the injector IS open into static air before the valve opens well before max torque which means the Honda does NOT have the benefit that sequential fueling was designed to give, and does give for best combustion.

[Scuffers]

Interestingly have done a lot of work fueling on my engines, and it is clear the K20's have sequential fueling only at low revs, on WOT throttle or above 2500rpm it looks like they go into old fashioned batch firing.

well, you have that 100% wrong too then.

they are sequential at all times (except when in fall-back fail mode and at initial start)

Ok I'll rephrase that - yes if you take the narrow definition of sequential as firing 4 injectors in firing sequence, that IS true, however in the sense that I had meant, that the advantage sequential firing gives when properly prepped fuel is ENTIRELY fueled into each cylinder in less time than the inlet valve is open, and the injector is not firing into static air before the inlet opens which is the same result as semisequential fueling, the Honda IS NOT fueling in the inlet valve opening alone.

IE to keep the injector small to give reasonable fuel prep at 3.5bar the injector IS open into static air before the valve opens well before max torque which means the Honda does NOT have the benefit that sequential fueling was designed to give, and does give for best combustion.

that's not the definition of sequential injection though...

that's quite simply saying that any engine that runs more than ~35% duty cycle (dependant on inlet cam duration) on the injectors is a bad idea.

Well, without going into the merits of if this is good or bad, you might just want to consider that no production engine out there (direct injection engines aside) do this, they all run well over that duty at high load/revs.

to spec injectors that are big enough to achieve max required flow without going over ~35% duration would be catastrophically stupid for several reasons, in no particular order:

1) emissions
2) fuel pulp/reg sizing (and increased cost)
3) idle/low load performance

[KingK_series]

that's quite simply saying that any engine that runs more than ~35% duty cycle (dependant on inlet cam duration) on the injectors is a bad idea.

Well, without going into the merits of if this is good or bad, you might just want to consider that no production engine out there (direct injection engines aside) do this, they all run well over that duty at high load/revs.

to spec injectors that are big enough to achieve max required flow without going over ~35% duration would be catastrophically stupid for several reasons, in no particular order:

1) emissions
2) fuel pulp/reg sizing (and increased cost)
3) idle/low load performance

Yes they run at 85% duty but not much above idle they are sized to fire before the inlet opens - which is bad for emissions and torque because the fuel falls out of suspension in static air, but doesn't matter in an OEM because they are not being tested for emissions much above idle.

on the other hand the intellectual reasoning for fueling with good fuel prep - ie best atomisation, at no more than 65% duty cycle entirely within inlet valve opening, and in fact starting as late as possible for best airspeed is for optimum compression, most complete HC burn and least possible ignition advance - IS what all best competition engines do, is what I am doing, and is what is achieved with direct injection.

I'll leave it to you to work out how without direct injection, -

[Scuffers]

Yes they run at 85% duty but not much above idle they are sized to fire before the inlet opens - which is bad for emissions and torque because the fuel falls out of suspension in static air, but doesn't matter in an OEM because they are not being tested for emissions much above idle.

since when?

may I suggest you look up the test methodology for EU2/3/4/5/6?

Have you ever submitted a car for FULL emissions test? - I guess not, having done so myself, I can tell you it's no simple idle test!

[KingK_series]

Yes they run at 85% duty but not much above idle they are sized to fire before the inlet opens - which is bad for emissions and torque because the fuel falls out of suspension in static air, but doesn't matter in an OEM because they are not being tested for emissions much above idle.

since when?

may I suggest you look up the test methodology for EU2/3/4/5/6?

Have you ever submitted a car for FULL emissions test? - I guess not, having done so myself, I can tell you it's no simple idle test!

nope I havn't, happy just to get the cars passed

but since I went to full sequential ignition, it has been very easy getting cars through

- the amazing thing was even Marl Bowles's EU3 s2 engine, badly mapped got through with it's original Emerald semisequential fuelling


- however better emissions are fine as far as I'm concerned, but it's not why I do it. -

[Scuffers]

Yes they run at 85% duty but not much above idle they are sized to fire before the inlet opens - which is bad for emissions and torque because the fuel falls out of suspension in static air, but doesn't matter in an OEM because they are not being tested for emissions much above idle.

since when?

may I suggest you look up the test methodology for EU2/3/4/5/6?

Have you ever submitted a car for FULL emissions test? - I guess not, having done so myself, I can tell you it's no simple idle test!

nope I havn't, happy just to get the cars passed

but since I went to full sequential ignition, it has been very easy getting cars through

- the amazing thing was even Marl Bowles's EU3 s2 engine, badly mapped got through with it's original Emerald semisequential fuelling


- however better emissions are fine as far as I'm concerned, but it's not why I do it. -

sorry, but you clearly have no idea what a full emissions test is, and no it's not an MOT test!

you can pass an MOT with just about anything, including carburettors, somewhat less sophisticated than sequential injection!

[tut]

You can also pass it with no CAT, no speedo, smashed headlight, and the odd sundry if you take it to the right place.



tut

ps:- just a reminder of my previous post, N3 on Craig Wallace's corner weighting scales was 765 kgs with a full tank of fuel.

[robin]

I agree that the Toyota fuel efficiency is not stellar. We had a S2 135R, 240PP exige and 135 VVTi S2 elise ("Elise S") running together for the same journey. The 135R always best, the Elise S in the middle and the 240PP always worst by about 10L on a full tank, whether caning it up and down hills or just cruising on the motorway.

In the past I've done similar trips with a n/a honda elise with the lower geared top gear, a more-or-less standard K in an S1 and a PTP165 kit on an S2. The Honda was always best the standard K in the middle and the PTP165 the worst by 5-10L.

Cheers,
Robin

[KingK_series]

sorry, but you clearly have no idea what a full emissions test is, and no it's not an MOT test!

you can pass an MOT with just about anything, including carburettors, somewhat less sophisticated than sequential injection!

- and apart from not being able to make sense of your english -

the point of running sequential ignition is to get best fuel prep - which will achieve better emissions as a by product of better torque


which you will not get with fuel being fired into static air where it will fall out of suspension - if you don't get that or the whole issue of best fuel prep, you are never going to map an engine to get the best out of it -

All modern competition engines time the injector opening off the valve closing timing and aim to get all fuel in in as fine a mist as possible after the valve opens and the later the better to use air moving at as high a speed as possible -

[KingK_series]

You can also pass it with no CAT, no speedo, smashed headlight, and the odd sundry if you take it to the right place.



tut

ps:- just a reminder of my previous post, N3 on Craig Wallace's corner weighting scales was 765 kgs with a full tank of fuel.

yea

not weighed my S1 recently, but with a bit of effort and a near std engine, std clams wheels, seats, I recon it should be about 660kg.

it'll be less with a KingK engine later this year.

[tut]

Really chuffed with the fuel consumption with N3 on road runs.

As you know, running with the likes of Scotty and Craig you are not actually hanging around, but the average is around 30mpg as the S/C allows you to be in 6th most of the time.

tut

[KingK_series]

Really chuffed with the fuel consumption with N3 on road runs.

As you know, running with the likes of Scotty and Craig you are not actually hanging around, but the average is around 30mpg as the S/C allows you to be in 6th most of the time.

tut

do you still have a na car?

looking forward to you seeing Stu's engine this year - hopefully he''l let you drive it, however will be good to put what is basically a sport 160 engine against a na honda car -

[tut]

No, N3 is S/C, N1 was N/A but was written off last year.

Must have missed something along the way as regards Stu's car. is this Stu Pollack that is fitting one of your engines?

tut