http://www.ecuconnections.com/forum/viewto...p?f=2&t=857, youll have to register but this link provides all of the info to recalibrate digi-1, alot of it is based on g60 maps but its easy to adjust to suit g40 digi 1, have a read anyway, you can also download the software 'tunerpro' for free and have a play

here a link to the moates emulator for realtime mapping for digi-1, youll also need a device (about £40) from a company called grautec in germany although this is mentioned in the thread

http://cgi.ebay.com/ebaymotors/Moates-Ostr...sQ5fAccessories

also a small device to alow for switchable maps

http://cgi.ebay.com/ebaymotors/Moates-2Tim...sQ5fAccessories

It's worth spending decent money on the emulator- the cheap ones crash and are crap (from experience).

You can map digifant yourself, you'll need to work out the locations of all the fuel, ignition, and various correction maps, rev limiter, etc etc.

Spend on a decent emulator, good quality wideband, and a knock detection kit- you'll have spent near £1k at this point

Will is right, Digifant is fully 'mappable'- but you've got to actually know what you're doing when re-calibrating a car, which I know is the part that takes the most time/effort.

Regarding Emerald, I've never been impressed with Dave Walker's articles in PPC, nor his ability to calibrate cars properly, Andy's came away with a crap map that pinked, and I know of other cars that have melted pistons due to incorrect fueling.

You cannot map round hardware problems- nor should you try to and charge for the privelage.

Oh, and the ignition drivers are crap on Emerald systems. Everything being equal between my car and Andy's, he's had numerous problems with ignition energy, which I don't have on digifant- I know of 2 other people running the K6 systems with the same problem, I can't comment on the new one.

If you're looking for a mappable ECU try 'Link'- they have excellent support and are starting to be used in high class racing applications, I have no personal experience of them however.

Be interesting to see how long the non-sodium filled exhaust valves last in the earlier Polo 8V heads, back then this was a really expensive process (Think Ferrari etc) so I'm sure VW wouldn't have done it unless necessary.

Interesting stuff.

As for knock detection kit, there are people on here who have witnessed me using mine. It involves a length of garden hose and an old pair of ear defenders. Extremely cheap and extremely effective, even on pretty noisy engines.

As for the sodium filled exhaust valves, I agree that they were obviously fitted for a reason. However my car never suffered with them, and my car had the 7mm stems too, rather than the 8mm.

However if you are able to give your car some serious stick (like an hour flat out on an autobahn) then you might be more likely to run into problems. A lot of turbo cars use normal valves though, infact series 1 RS turbo's had sodium filled valves but series 2's didn't. Either cost saving or there was no need for them.

The link management kit looks good, perhaps somewhat beyond what your average polo requires though. It looks expensive!

As for the sodium filled exhaust valves, I agree that they were obviously fitted for a reason. However my car never suffered with them, and my car had the 7mm stems too, rather than the 8mm.

and the head is still going strong on my N/A car

Be interesting to see how long the non-sodium filled exhaust valves last in the earlier Polo 8V heads, back then this was a really expensive process (Think Ferrari etc) so I'm sure VW wouldn't have done it unless necessary.

Have to agree.

You will have the valves out anyway.

Interesting stuff.

As for knock detection kit, there are people on here who have witnessed me using mine. It involves a length of garden hose and an old pair of ear defenders. Extremely cheap and extremely effective, even on pretty noisy engines.

As for the sodium filled exhaust valves, I agree that they were obviously fitted for a reason. However my car never suffered with them, and my car had the 7mm stems too, rather than the 8mm.

However if you are able to give your car some serious stick (like an hour flat out on an autobahn) then you might be more likely to run into problems. A lot of turbo cars use normal valves though, infact series 1 RS turbo's had sodium filled valves but series 2's didn't. Either cost saving or there was no need for them.

The link management kit looks good, perhaps somewhat beyond what your average polo requires though. It looks expensive!

One of the current VAG sign off tests for development engines is 100Hrs at peak power/speed- possibly required to pass this.

My BV Head doesn't have sodium filled valves and is fine.

Regarding DIY knock kits- they are good (I know engine test facilities that still prefer their copper tube set-up than sound equiptment!) But it wrecks your ears during a full mapping session, and you can't filter noise.

Mind you they cost £5, not £400 :-)

Perhaps sodium filled exhaust valves were just something manufacturers used in higher performance engines of the 80s and 90s because they could seeing as my E36 318is had them... Not a high performance car admittedly, but the engine was fairly high spec...

My Mk2 16v has them as well as far as I'm aware

Edited 29 December, 201015 yr by tobyk

140bhp from 1.8 litres isn't exactly a 'high spec'

Probably due to life rather than out and out performance.

Well I was speaking in terms of the variable length inlet manifold, semi-sequential injection, distributorless ignition, vernier pulleys, forged rods, forged crank, etc, so had a good few bits on it. It's a 22 year old engine design... But no that power output isn't anything spectacular.

The exhaust manifold is a work of art though...

Alrights guys,

Starting to hoard parts for a charged ABD (supercharged), i'm going to be running standard C/R , gradually increasing boost with different set-ups.

I'm wanting to use a downdraught carb, so unfortuently ruling out the A-series SU and HIF boost capeable carbs, looks like it will be a R5 carburettor or the sealed weber range. All the custom work will be done by myself so thats not a problem.

My question is, which supercharger would work best with a carburetor? which is cheaper?

Also, if i used a G40 charger, on a standard pulley, what boost would it be running?

id say if you really want to use a blower to go with a centrifugal one like a rotrex but they arent cheap, you other options are g lader as youve already said, which would be good for easy installation or a roots type blower like a eaton m45 off a mini, is there any reason why you wont go down the turbo route?

Mainly because i can still accomodate a standard exhaust system, ease of installation, preferance.

Yeah i've had a look at m45's

fair enough, i do like the idea of running a charger one day, ye m45's are ok but seem a pain to install well, i would probally go with a g lader if i was you, probally not the best one for all out power though, depends what you want out of it though i suppose, another thing to bare in mind is that you get about a 3 psi pressure drop across a solex dis

I ain't going for all out power, just a reliable boosted unit. Utilizing a carb and supercharger.

What boost does a G40 run standard then?

I ain't going for all out power, just a reliable boosted unit. Utilizing a carb and supercharger.

What boost does a G40 run standard then?

Standard according to haynes is around 0.5 bar

Are you going to run standard internals Max?

I'm running standard rotating internals yeah,

ABD uses pretty heft con-rods and pistons.

Think i've sourced a couple of solex carbs

I'm thinking of running draw through now....

Just weighing it up really, what would be best.

I've got a pretty much brand new double choke weber in the form of a 28/36 DCD (from my old engine), and I'll be using a supercharger, either a G40 or small eaton.

Has anyone ever had any experience of this sort of set-up? I'm worried about having such a large distance between the carburettor and the ports, will fuel atomization be a problem? Its a long way for the mixture to travel i thought, especially if its got to go through a charger.

Anyone got any thoughts?

i was trying to work out the whole suck through setups in my head earlier, something iv never researched or looked into, is it like,

Airfilter > Carb > Pipe > Turbo/Charger > Intercooler?! (surely the air fuel mix cant travel all this way?) > Pipe back to an inlet to ports

Or can you only run draw through with a charger? Seems mad for the air/fuel to go so far?!

If I was carbing I think id prefer blow through tbh?

Cant use an intercooler. Carb > Charger > Engine, by the shortest possible route.

The theory is that the fuel atomisation cools the air going into the charger. Also the charger is used to mix the air/fuel better.

Most carbs need to be sealed for blow-thru charging to work (there are fully working methods of turboing bike carbs via blow through) but pull through is far easier a setup with carbs.

http://www.youtube.com/watch?v=jQdS1shlzYw

I'm thinking of running draw through now....

Just weighing it up really, what would be best.

I've got a pretty much brand new double choke weber in the form of a 28/36 DCD (from my old engine), and I'll be using a supercharger, either a G40 or small eaton.

Has anyone ever had any experience of this sort of set-up? I'm worried about having such a large distance between the carburettor and the ports, will fuel atomization be a problem? Its a long way for the mixture to travel i thought, especially if its got to go through a charger.

Anyone got any thoughts?

i wouldnt go suck through tbh, the only way i can see it been done well if you really needed to would be to mount the charger on the inlet side of the engine on a custom inlet mani with a nice sidedraught carb on the inlet of the charger, think youd only be able to use a eaton due to g lader probally not liking the petrol passing through it

id stick with blowthrough, convert you dcd to a preassurised carb if youve got your heart set on using that carb

How about supercharging an AFH with the 1.6 upgrade?

Returning to this again, sold the solex DIS to get some funds together for a holiday, so now i've got the choice again to buy another one, or use the DCD weber i've got.

If i'm gonna use it, its obviously gonna have to be suck-through, which would be a very limiting factor as they're could be no charge cooling,

Which leads me to think maybe it would be a better idea to convert it to a sealed unit, which is something I'm gonna have to research, has anyone ever touched on this?

One idea was to use a set of CBR600's instead of the DCD,

Also, anyone know if the G40 charger would accept fuel passing through it?

Probably not a good idea with a G40 'charger - the Apex seals inside are lubed by either breather gases (if boost return connected) or by PTFE spray people add when removing the boost return. Can see the petrol doing a nice job of degreasing the internals.

That was my thought, will rule that out then!

Having looked at what exactly converting a weber DCD (or any simular carb for that matter) entails, seems a lot of bodging for not a lot of gain/control.

Will more than likely be using a turbo now, and going suckthrough.