Turbo ignition timing-carb'd engine

[goldenwonder]

I've got a long term plan to do a turbo conversion on a car.
Pretty straight forward stuff-carb I've already got sorted, manifold isn't much of an issue, neither is the oil supply for the turbo.
What I'm struggling to get my head around is to sort out the ignition timing for when it's on boost & where I'm hoping someone might be able to help?

As I understand it needs to be adjusted to retard the ignition timing as the boost increases, but how can this be done with a car that doesn't have an ECU of any sort?
It's very basic engine design running a very basic distributor with vacuum advance.

Any advise very gratefully received!

[sparkyt]

It's easy bud just go find a dizzy from a Saab 900 trbo .. dizzy in block type ..

Then take the vac unit off and fit it to your dizzy ..

Simple ..


Your dizzy will advance untill it starts to see boost then it will retard ..

[sparkyt]

This is beetle dizzy with Saab vac unit fitted

[goldenwonder]

Now that sounds very interesting, thank you for that.
I'll try & source one & give it a go.
Is it really as straight forward as that?

[Adey]

There are also other cheap mappable ignition only systems out there, you could also try wiring in an aei off a renault 5 gtt same thing but the advance and retard is built into the coil rather than the dizzy but it would then need a specific trigger pick up.

[pepe]

I'm going to use the twin port vacuum canister on my supercharged carb build, been used a few times by all accounts, what carb are you using just out of interest? I'm looking for a r5 gtt carb and fpr at the moment!

[goldenwonder]

I've got a very early diahatsu turbo carb, so it bolts straight to the original toyota inlet manifold-just needs re jetting to suit, but even they swap out from the toyota 5k carb (or so I've been told)
It's a very long term project & a little knowledge can be a dangerous thing, so want to get all the info I can before I get stuck into it properly.

[pepe]

ok cool well if needs be you can always drill the old jets out to desired size! sounds intersting! got a build thread? what car/engine is it?

[goldenwonder]

NO build thread yet-I'll wait until I know I'm going to get stuck in to it.
It's one of my Starlets, did an engine swap, so it's now a 1500 instead of the original 1.0 with a custom Kent cam, bit of head work, but nothing huge.
Turbo conversion just seems like something fun to try as I've got a screamer in my other car.

[pepe]

Exactly why I'm doing it! For the fun of it and basically the vw scene is Abit samey, so I thought I'd switch it up abit, I've been told numerous times not to bother put an Abf/KR gti lumps in blah blah but I'm not too fussed what power it makes aslong as it works looks as OE as poss and its reliable that's the main thing for me, been pretty cheap so far aswell! Not even £300 in and all I need is carb, fpr and sort out piping! And £240 of that went on a fresh 0 mile g-lader charger

[pepe]

Also if you have a solex/pierburg carb and need some info let me know what model and I'll see id I can help you as I have the pier burg/solex Haynes book!

[goldenwonder]

Thanks for the offer, but it's an Aisin carb, so not very well known & to be honest not the greatest-but it's what I've got & I'm going to work with it!
Knowing me it'll be years rather than months before it's sorted, but I'll get there.

[pork]

I welded my dizzy, the piece that the weights spin out into, I just reduced the space they have to move out into, left the vac advance on too

Aldon amethyst do somthing that can be adapted to fit a standard dizzy, and can be programmed by laptop (I think)

[pepe]

what do you mean welded the dizzy how?

sorry i cant help you with the aisin carbs dude!

[pork]

Was like this



Then after welding

[pepe]

does the timing just stay retarded then after locking the dizzy? how do you set idle timing by turning dizzy body?

[pepe]

also would it be a good idea to remove the springs and weld it in the fully advanced position so that if the weld break it doesnt fly into fully advanced position and potentially damage the engine?

[pork]

Sept 26, 2014 7:57:03 GMT pepe said:

does the timing just stay retarded then after locking the dizzy? how do you set idle timing by turning dizzy body?

Yeah.

Worked fine for ages, but gone with ecu and injection now

[doobie]

If the system is the same as the turbo mini blow through you will also need a fuel pressure regulator that increases with boost....

[pork]

Yup, used that with my turbo bike carb build.

Boost referenced fuel reg,
1 bar fuel pump,
Welded up dizzy,