Vacuum advance with IDF or DLRA's DONE!!

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Wally
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Joined: Mon Oct 28, 2002 12:01 am

Vacuum advance with IDF or DLRA's DONE!!

Post by Wally »

Today I have finally proof from my strobe that my modification on my daily driver 1,8 ltr AN engine with my IDF/DLRA (I tried both sets I have) set-up gives a full 10-12 degrees vacuum advance with a light throttle opening!! :D :D

What I did was using a set of Alfa 33 carbs which have one vacuum port on ONE port on ONE carb. That didn't give my T3 vanagon electronic dizzy with the stock vacuum can enough vacuum signal.
However, the other carb has the casting for the vacuum port, but its just not drilled and doesn't have a small hollow pipe stuck in it.
The original pipe has the same diameter as a brake line, some just drill the othe carb for the extra vacuum port, glue a piece of brake line in it (about an inch length) and connect a vacuum line with a 'T' to the other carb. Done!
The strobe showed a perfect stabile extra 10-12 degrees advance with the vacuum line connected :D

I now have a 40kV electronic dizzy with an excellent advance curve and vacuum advance at cruise :D :D
Bye, bye, all 009's and this is even cheaper :twisted:

It took me a while to get this going, but the result is well worth it :twisted:

Greets,
Walter
T4T: 2,4ltr Type 4 Turbo engine, 10.58 1/4 mi in a streetlegal 1303

"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks
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Piledriver
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Post by Piledriver »

Those are easy to recurve as well, all thru the side access plug.

That's the setup I run. (With CIS)
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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Steve Arndt
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Joined: Sat Mar 10, 2001 12:01 am

Post by Steve Arndt »

I added ported vacuum to my CB 48mm ITBs by copying the dimmensions for the port from a late model Weber IDF.
See the circle in the pic..


Image
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bj
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Post by bj »

steve,

just wondering...what are you using these additional ports for? i'm rather new to FI, but i thought CB units already had those ports?

thanks

bj
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Tony Z
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Post by Tony Z »

I've been running it for ages on my T1. 36IDFs. Both the IDFs are tapped for the vaccuum on both throats.

I join the throats of one carb with a T and link that to my dizzy. 1.9 waterboxer dizzy. 31BTDC mech, 44DBTDC with vac
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RG64
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Joined: Thu Mar 03, 2005 7:46 am

Post by RG64 »

So Wally, how much of a difference is it making and where do you notice the most change???


Rick
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Wally
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Post by Wally »

Excellent to hear that Tony!
I am glad somebody else is confirming my experience 8)

Personally its to early to tell a mpg improvement (haven't done a fill-up yet) and my temp measuring gauges are on another car at the moment.
It does seem to accelerate a bit more eagerly just off idle and at cruising speeds it just runs more smoothly and has a bit more throttle respons imo.
T4T: 2,4ltr Type 4 Turbo engine, 10.58 1/4 mi in a streetlegal 1303

"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks
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knalpot
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Joined: Tue Mar 08, 2005 4:18 pm

Post by knalpot »

Hallo Wally,
I have 36 and 40 DRLA with only 1 vacum ports/bronze pipe, so do you think I need to drill other port ?? I want to make sure my unilite get enough vacum signal.
GR
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Wally
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Post by Wally »

knalpot wrote: , so do you think I need to drill other port ?? I want to make sure my unilite get enough vacum signal.
GR
I dunno about the Mallory. I can only tell you what my exact combination did for me.
Nothing wrong with trying the single port first? :wink:
T4T: 2,4ltr Type 4 Turbo engine, 10.58 1/4 mi in a streetlegal 1303

"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks
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FidoDido
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Re: Vacuum advance with IDF or DLRA's DONE!!

Post by FidoDido »

Wally wrote: I now have a 40kV electronic dizzy with an excellent advance curve and vacuum advance at cruise :D :D
Bye, bye, all 009's and this is even cheaper :twisted:

It took me a while to get this going, but the result is well worth it :twisted:

Greets,
Walter

I've tried quite a few dissys now, and I do like the T3 set-up. The UK ones used a 071905205 distributor. However, I find that this distributor does not give enough advance between 2000 and 2800rpm. I use my engine in a bus, so this shows up with heads running hotter than they should and some loss of torque at these rpm ranges.

I wonder if it would be possible to swap the springs in the stock 022905205 distributors to give the T3 set up a better advance curve?

THe above effect is slight - but my heads with this ignition ran hotter at 45mph (around 2500 rpm) than 65 mph (3800 rpm) - probably due to the weight of the bus combined with slightly retarded advance compared with where the engine wanted it...

Good work on the ports :)
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