X flow head?

However its skinned it takes time to do it...

Watch the fuel pressure with a guage, it varies by about 5 ercent since the fuel pressure (3 bar?) + the manifold pressure change still only gives the CORRECT 3 bar over manifold.

The carb does not have to moving your foot directly pushes fuel in via the accelerator pump to compensate for the fuels greater inertia until carbs normal fuel flow catches up.

And a computer is always slower.

Reply to
Burgermans other computer
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You dont need aceleration enrichment. The cars acelerator pump simply makes up for the fact that on opening the throttle the correct ratio goes lean because fuel has greater inertial value than the air. It corrects it.

On the cars map, since the fuel is pumped at 3bar or so this isnt an issue. What is is that the computer first has to see an increase in airflow before it can "fix" it! It takes time.

Or maybe your system does but you

It cant. Because it does not yet know how much to increase it until it sees the pressure change (which may be ongoing) in the intake, and how fast the revs are rising. And even if it could, they dont! Throttle position sensors typically have 3 positions. Idle, so the screw on the bulkhead can control idle co. 2 for everything else (mapped) apart from full bore. And full throttle which is a fixed safe over rich full power with only knock sensor to retard timing if it is sensed. (no closed loop)

It does not WANT to be richer! Only correct, which a computer cant do because its always a step behind in dynamic condsitions.

You may be able to correct it a bit (but not initial throttle plate movement) by richening it up under acceleration so it covers the computers delay. But that cant work when you suddenly touch the throttle at idle.

You wouldnt need a delay if the computer kept up!

Reply to
Burgermans other computer

Name a single fast drag car that uses it!

Reply to
Burgermans other computer

Can't name a car. But Chris Hall's "Wot No Turbo" Comp Bike when it was a 1400cc (1460?) Kawasaki ran the original DFi with some home brew tweaks. Mind you most of the fuel went in with the three stage nitrous oxide (1=80, 2=120, 3=1+2=200, total with fuel and air 280bhp, made about 140bhp without the no2) The DFi got it off the line and up to the point it could take 1st stage no2 without lighting up the tyre. Strewth it has to be over 15 years ago, at least 5 years before you had my mates GSX-R on your dyno at Darley Moor.

The fact that Chris was the only person ever to get 100% on the IBM grad aptitude tests may have helped.

Reply to
Peter Hill

Every time you mention your 75 track car I have visions of a rover 1.6. It's quite amusing.

Reply to
Depresion

Dont remember darley moor? But I dont remember much from 10 years ago!

I remember that name... Most people scrapped the fuel injection on those because a)unreliable as hell - and even slower than modern stuff! But on bikes and on the strip the idle can be set rich enough to cover the initial flat spot. In fact on those fi kawasakis it had to be! b)throttle bodies tiny! Which doesent matter on nitrous of course...

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Reply to
Burgermans other computer

No the stock VW 256's need 14", Willwood do low profile 4 pot callipers to fit

256mm disks that clear most 13" rims as used by a few G40 owners.Try speaking to Eric at AAT,
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they can advise you on bits and possibly get you a decent price on them.
Reply to
Depresion

You could always use the old Audi inboard disc setup. The disk is bolted in at the inner CV joint and the caliper mounts on the diff housing.

Reply to
Peter Hill

Catchup with what exactly? do you have any idea how fast a modern efi ecu is?

Reply to
ThePunisher

Yes.

First the airflow increases. Now its weak. Then the sensors and computer see it and try to fix it, it slower than the initial airflow increase. And no matter how fast they get in the future they will always be behind the airflow, sensors, and the resulting extra fuel.

Reply to
Burgermans other computer

Oil accumulator, second hand. Keeps the oil pumping through teh engine when cornering and sucking dry on the sump. Call that about 50 to 150 notes.

Hard springs and shocks. Harder the better, frankly, you trade comfort for rigidity, but there is a break even point among the "seriously hard" end for track which you'll have to spend much more to approach so just use what you can afford. Call that about 200 notes second hand, dunno new. Don't make an effort to have the car sit a lot lower, this is unlikely to improve things much. Higher budget you can adjust the angle of the various suspension control arms to lower the car.

Engine, well, the cam is crucial at this price level. I don't know the engine so I don't know what the options are, but broadly speaking you can raise peak power at the expense of torque, or both at the expense of economy in conjunction with a carb / EMS tweaking, but you can usually improve the power into a high power output over a limited, high revving band where if you thrash the engine right you can go faster. I say about 200-300 for a cam, followers and adjustable cogs / chain.

Changing a cam is relatively cheap - raising the red line is a challenge. slapping in a turbo or supercharger is another thing to consider, ebay may have such things. If you're not planning to do formulas then burgerman can advise on nitrous, which is cheap and sickening bolt on power that gives the best of all worlds. Dunno but I guess 300 squid?

Reply to
Questions

Can you reccomend some brands for the accumulator? And do you think my Koni adjustables will be ok, I can crank them up onto the hardest setting?

I have Kent cams atm (I will measure the angle tomorrow), and I know someone with a matching vernier pully for sale.

I think I will go the nitrous route, since turbo power seems as though you need allot more cash to get it done correctly than I currently have at my disposal. But refills might be a pain in the bum :( but it will be the last thing I do and probably late next year once I have enough for a decent install, unless I can convince burgerman to help me with a DIY kit :)

Reply to
REMUS

woah

this is getting tense, I dont have the knowledge/experience to jump in here, but im with the burger man, as Im absolutely starving...

Reply to
Theo

Except when they are drive by wire and can predict the fuel demand from the change in pedal position and the current demand?

Reply to
Tim S Kemp

You never know!

Reply to
Burgerman

Probably but now not only is the fuel "late" but so is the throttle plate movement! It cant ever get it totally right even doing this though because it does not yet know how far or how fast the throttle plate will move (unless it takes control away from you and decides for itself?) And it cant yet know the rate of rpm rise. (load)

Reply to
Burgerman

hehe! Well don't be suprised if you get an email sooner or later ;)

Reply to
REMUS

You might see it that way, but to most of your combatants... I think they probably see any correction to their views as a threat tbh. No one seems to be providing proper information... someone mentioned a WRC car... well which bloody one! And what is the sub system you are referring to, where is the tech article proving the details provided!?

There is little proof, just idle hearsay, opinions and jaded personal experience imo.

I understand most of what is being said... and allot of it is being repeated tbh. These sprawling threads don't really make for coherent arguments, and I think that sometimes people come away from these 'conversations' with less accurate information than to begin with.

Reply to
REMUS

Not from me.

Reply to
Burgerman

Yeah, sounds like somthing a Jedi would say!

Reply to
REMUS

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