It cost me at least £300 in the end to bike carb mine, and it was worth every penny. The noise, throttle response, perfect. I'm not even interested in comparing it ton anything else, it just makes me happy blatting it on a country road. I just wish I had more GRIP!

You shouldnt be having grip issues with an afh

A properly setup ignition is severly underated...

he doesent have an afh. and why wouldnt you have issues? putting the power down with a car that weighs as much as a shoe isnt always easy!

Edited 22 February, 201214 yr by erixtar1992

It cost me at least £300 in the end to bike carb mine, and it was worth every penny. The noise, throttle response, perfect. I'm not even interested in comparing it ton anything else, it just makes me happy blatting it on a country road. I just wish I had more GRIP!

You shouldnt be having grip issues with an afh

A properly setup ignition is severly underated...

he doesent have grip issues. and why wouldnt you have issues? putting the power down with a car that weighs as much as a shoe isnt always easy!

I know that i had a 1341 g40, i was ok for grip in the dry with alot more power and torque you can get out of a basic afh setup. Dont want to go off topic though.

I would say it's totally down to the jimmy fitting/tuning the engine, most don't really have proper experience of what they're doing.

In theory, they should work, and work well. But only if they have been properly set up against the components the engine is utilizing, and the fitter actually knows what's going on.

Yes, a well sized matched set of bike carburetors is going to be able to supply higher peak CFM into the chambers of an engine, than the typical standard EFI set-up, but that fuel/air mix has to be totally homogenous, as close to the correct ratio, and ignited at the correct time (all depending on load and engine speed) for it to be burnt efficiently and effectively to prove an increase in power, which is where people fail in my opinion.

The most frequent set-up we see is totally strangled by a very conservative, ancient distributor system. Which still has the timing advance curve that controlled a 35-41KW 1.3 8 valve engine, and people scratch they're heads and post on numerous threads wondering what's wrong? You'd see huge improvement by getting it weighted differently to give the required curve for the desired set-up, or better still adding an MSD set up, using multiple ignition sparks.

It also relies on who's done the manifold work, its size of bore & runner length, and its transition quality from carb to manifold, then manifold to cylinder head. Tiny intrusions can have great effect on the homogeneousness of the mixture, making one cylinder produce less power than its neighbors, also effecting "swirl" and "squish" effects in the chambers. Choice of other modifications also has a big say, cam and cam-timing choice etc.

It would be really interesting for people to temporarily run standard EFI and ignition instead of Bike carburetors. Peak flow may be reduced, but the engine would receive a much better matched ignition curve, and suitable AFR in all conditions.

Agree with things max has said, but also theory doesn't always reflect in reality, different engines behave different ways in different applications and such, at the end of the day, I own a polo, it's just a bit of fun

Is there anything to stop you throwing your old ECU, harness and dizzy back on just to run the ignition timing to see what happens?

Is there anything to stop you throwing your old ECU, harness and dizzy back on just to run the ignition timing to see what happens?

Exactly what I questioned but got shot down..

What about using the KR ECU because it only needs a temp sensor, vacuum line and (air mass?); probably mappable too?..

There isn't andy no, although it's for a 1.4 as I never got the AEE ecu.

On my mates fiesta we have lost the maf and lambda, but retained everything else.

TPS is the key one, open up the throttle and it advances the timing, but as it has knock sensor it keeps itself safe.

Trouble is I'd lose map, inlet temp, tps, lambda.

I'd only have coolant temp and knock lol

The CBR's have a TPS though?

Yeah I know that man, I might look at doing it.

I'd have to splice my rev feed ECU side of loom also instead of to clocks haha.

I want one of them boxes off Aldon tbh!

Guy you're welcome to come in my car and hear the noise, even though I have an airbox which quietens it tbh

I might have to take you up on that arris, closest I've been in to a bike carbed car was Danny lee's mk2 on twin 40's and that sounded the tits being ragged through a multistory car park

Are you still thinking about boosting it too?

Yeah that was jokes Ben, thing is through twisted logic I can kinda see where he was coming from, but just NO

If I was going for big power that would be the route I'd take, but I would need forged pistons for that and its not a route I wanna take at this stage. I'd rather do it on a budget and if I can get a good 180bhp reliable with an eaton I'd be well happy. If I can do that then the next stage probably would involve turbo's and itb's and probably revert back to 1.4

I might have to take you up on that arris, closest I've been in to a bike carbed car was Danny lee's mk2 on twin 40's and that sounded the tits being ragged through a multistory car park

Are you still thinking about boosting it too?

Yeah man, obviously it will feel dog slow compared your mk2 but yeah we'll go down the A444 or something.

And yeah. Ko3 on bike carbs haha

Is there anything to stop you throwing your old ECU, harness and dizzy back on just to run the ignition timing to see what happens?

Thats what i mentioned earlier in the thread, I'm sure its been down before.

Is it an early (mech head) or late (hyd head) mk2 dizzy that fits onto the afh?

I'd assume that it was the late one, since the early one had points? Atleast, I think it did..

I'd assume that it was the late one, since the early one had points? Atleast, I think it did..

Yee late one

Guy didnt you ever hear my blue GT on carbs?

Not sure If i was in that or the green bready GT :S

I'd assume that it was the late one, since the early one had points? Atleast, I think it did..

Yee late one

Shame,could have run a kr setup then as that dizzy matches up to the early polo engines.

^^ couldn't you just swap the drive pins over?

^^ couldn't you just swap the drive pins over?

I dont remeber them being that similar, its the reason when converting a mech head engine to electronic people search for saab dizzy's and kr ones istead of using a late spec polo one

I'm gonna contact aldon about their little box of tricks, then it will be mapped properly not a compromise of random other engines

And could be remapped when you add boost

Matt I don't think I saw your car on carbs, wasn't your green GT bready the oak green one? I've seen plenty on them tho and even had a set of 45's on a 16v scirocco (although never got to drive it ) so I know they sound fucking cool but only ever actually been in one car with them and that was just a quick blast through a car park. I was just thinking of the performance side of things, I have not and never will try and claim multiple carbs don't sound cool :-D

Lol I remember your GT at spring fest matt

Call Aldon automotive.

They are bringing out a box which is mappable ignition using the hall sender in a dizzy, including a rev limiter, immobiliser and 3d mappable ignition.

Interesting..

I had thought about MegaSquirt'n'Spark.

That can run off a Hall Sender, rather than a 36:1 trigger wheel and EDIS of £300 MegaJolt, could be used for carbs to begin with, then switch to Fuel Injection later, but it's more like £400 new and Omex or Haltech or Emerald aren't much more.

Aldon's price sounds nice.

So what are the 3d for mapping for ignition?

revs

manifold pressure or mass airflow or throttle position sensor

oil/coolant temperature

exhaust temperature

air-fuel ratio

boost pressure

?

Not sure, I thought 3d was just another dimension of adaptation factors

The three dimensions will be load, rpm and ignition advance. Centrifugal advance only gives you rpm and ignition advance (with vacuum advance for fuel economy as a token effort towards varying timing with load).

How load will be determined I'm not sure, if they're intelligent they'll make it flexible so you can use TPS or MAP at the very least.