Making your distributor boost sensitive?
Turbo Mini Forums

It has just occured to me that a vacuum advance could be made to "Boost retard". I was looking at getting my dizzy curved and leaving the Vac Advance off. I'm sure I have heard something somewhere.

Am I talking bollocks? Or is this a do-able thing?

stu

Bugger off, I'm getting there.

When the dizzy senses boost it naturally retards as per no vacuum.

Early SAAB turbo's used a two-port vac advance unit... One for vac advance, t'other foir boost retard. Very clockwork, very antiquated, very 1970's, very crap.

With a supercharger, unless you have a throttle by-pass, you'll never see vacuum except maybe on the over-run, so you may aswell try and do something...
Personally, I'd rig up a by-pass first, and sort the advance after.

In fact, I'd build the bugger and then optimise it! Come on Stu, get it made, then worry about the fine tuning...

Edited by turbodave16v on 30th Oct, 2004.

I just use a boost retard unit as what daves mate graham is building. Sure he will have them up and running by the time yours is built up

I'm getting there, in the meantime, I enjoy talking about it.....All knowledge is good knowledge. I am just waiting on a few bits now.

Bugger off, I'm getting there.

well there should be two guys from this board running these ECU's at the mo...
And the 'live' one in my sierra has got 9,000 miles on it now, so it's looking good.

how`s this coming along ???

Everyone knows that instructions only have to be read if the thing doesn't work....

If you're talking to me, big piles of bits and I have just realised I'm going to be cutting wheelarches....shame. Should be ready to fire up in about a week, (a week in next month, probably). That's when I will have a very bodged up test engine. Have 3 to explode, so will be doing lots of testing. I have just realised how little I know and so the first one will probably last a very short time. First thing will be to find out what the limit of 8:1 is on that blower with a Vauxhall TD intercooler (looks crap) but that's what I have right now. Will have photos in due course.

Bugger off, I'm getting there.

Those vaux (car) intercoolers are a good efficient design... Nice and compact aswell!