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Turbo and Vac Advance query!
Simon - 6/10/06 at 08:47 PM

Peeps,

As you may know, I'm planning on turbo'ing Deimos. Now, given the engine is fairly old and has a distributor with vac advance, could someone tell me how the vac side is supposed to work under boost

Thanks

Simon


mark chandler - 6/10/06 at 08:58 PM

On the turbo techniques range rover I had the vacumn was blanked off.

The EFI was standard hotwire with a piggy back ecu and a little pot to trim the engine so pretty basic.

I believe all they did was port the heads and stick in a spacer to lower he comp ratio. This was rated @ 250 bhp, just over 100k miles when I got it and going strong.

Hows the diff conversion coming on ? are you doing this prior to whooshing the engine or all bits at once ?

Cheers Mark


Simon - 6/10/06 at 09:05 PM

Hi Mark

Finished yet?

Was planning on going to a rolling road before any work starts, but as I've been planning on starting after Kit Car Live (week Sat), that won't happen.

Now thinking about doing whole job in one go, and be off the road for a couple of months (hopefully less).

Started making exhaust manifolds (well one anyway) today, hopefully finish it Sunday (1st opportunity). I'll put up pics as I go (starting Sunday!!!)

Are you going to Brands on 14/10?

ATB

Simon


mark chandler - 6/10/06 at 09:10 PM

Just about, Brakes sorted engine runs, just air filter paint and a bit of love for a track day car.

Just seen this on Fleabay

I gnition retard

May be of some use, I thought you were goinng down the megasquirt and spark route.

I doubt if I will be going to Brands for a show, think I have all I need now and cannot aford to think about any extras.... My next project will be v8 rear engined if I can find a suitable gearbox.

Regards Mark

[Edited on 6/10/06 by mark chandler]


Simon - 6/10/06 at 09:21 PM

Yeah either MS or Emerald, but only for fuel. Trying to do it on a (small) budget but think it's gonna come close to £800

May think about spark at a later date.

ATB

Simon


mark chandler - 6/10/06 at 09:37 PM

Your welcome to try my old megasquirt to see if that will suit your needs, its all loomed up etc for a rv8, only problem was holding injectors on full time which is probally due to flux between some pins.

Let me know.


Regards Mark


Simon - 6/10/06 at 11:34 PM

Mark,

That sounds grand

I've got a set of injectors here, so between us, we may have a good set. I suspect they may not be up to fuelling requirements and I may have to invest in a higher flow set.

Do you want to sell the MS or loan? Either is good for me.

ATB

Simon


mark chandler - 7/10/06 at 08:44 AM

I,ve also got a set of 4.2 jag injectors that go with it that I will need to dig out so fueling should be fine.

Loan I,m afraid as it goes with my 4.6 engine, but if you can sort the mapping out then you can clone easily enough, failing that go chase an emerald.


Regards Mark


Volvorsport - 7/10/06 at 09:54 AM

when you get into boost , it will retard , which is what you want .

you may have to fix the amount of retard/ advance , it can physically get tho .

Most turbo dizzys have the ability to retard under boost .


Simon - 7/10/06 at 06:56 PM

Mark,

Perfect - was gonna say, will just need to copy map - if I can get it right. I'll give you a call nearer the time (got your number on computer somewhere).

Volvosport

I'm not doubting you, but don't understand. I always believed that the ignition was advanced during higher revs to get the spark to the pot earlier, so things went bang more on time. Trouble explaining myself here

ATB

Simon


MikeRJ - 7/10/06 at 09:34 PM

quote:
Originally posted by Volvorsport
when you get into boost , it will retard , which is what you want .

you may have to fix the amount of retard/ advance , it can physically get tho .

Most turbo dizzys have the ability to retard under boost .


I think the point is that the distributor currently has a standard vacuum advance for it's original naturaly aspirated application, which I suspect wont be able to retard on boost.