Engine is a 383, 10.71 to 1, running on 93. Carb is a 750 dp mech secondarys, 4779-7. 6.5 psi on mech fuel pump.
converter is 2600 stall from ptc. Ignition is msd6al2 programmable, tried 12* to 22* at idle, all in by 2300, locked dizzy at 42* but program to stop advancing at 38 for now. Engine was dyno made peek at 42*, 470hp, 480 tq.
I cant get the idle circuit to lean out. Can get afr to 14 or so by turning mix screws but am 3/4 turn out. Put car in gear and it wants to die leans out. Idle around 800rpm. Back screws out 12.5 afr and I can get it in gear wo stalling, rpm drop of maybe 50 to 100 rpm. Makes about 10 to 12" of vacuum. Runs good, great transfer, slight bog but I know what that is.
i want more adjustment from screws. Transfer slot is a square on both prim and sec.
Have quick fuel metering blocks 34-105qtf.
Jets are 71 and 83.
What I've done,
IAB- prim- .075 stock to .079 to .082
IAB-sec- .066 stock to .070 to .072
Haven't touched HSIAB as dont care yet, need to get idle circuit first. they are .031 on all 4.
metering blocks
IFR- .031 to .033 to .030 to .027
PVCR- .062
Emulsion bleeds- .026
PV 4.5
PRIM and SEC nozzle .031
I cant believe it hasnt leaned out! I've studied and researched this and am pretty darn knowledgeable about this. I modified my body to accept screw in air bleeds also.
if anyone has any ideas let me know please! I was going to try and go even bigger on IAB and .003 smaller on restrictors.
I am almost wondering if my afr is bad but when I look at plugs they are rich.

Thanks!
Dan

 

Those plugs are 98% idle time fyi

 

Do you have any vacuum advance built into the curve? I have a similar setup, and mine died when going into gear unless it was crazy rich as well until I fixed an issue with that. Mine likes about 32* at idle with the vacuum advance.

This should allow you to close your throttle blades a good bit which should add more sensitivity. The secondary showing a square of the transfer slot seems way too open compared to what I usually see.

Good to see Powell Machine getting some more business too. He’s a good dude, and I ordered several parts through him as well as having him milk down my heads.

 

So with this 6al2 programmable box I can run a 1 bar map sensor and have it add timing in relation to vacuum. As of now until I work out these other bugs I just have a flat curve in that graph.
I can program in a base of 32 deg tho, box has a retard feature built in.
I'll reset transfer slots in both prim and sec and add more initial timing. Figured 22* would do it but I am fairly green to tuning. Ya know this all started from that damn tv cable on this 700. Has to be adjusted correctly AND engine must be tuned correctly. Got the cable dialed in thanks to bowtie overdrives, highly recommend the kit they have, and am now tuning.

Yes!! Daniel at Powell is great! Very very knowledgeable guy. I met him on a fb page.

I'll try more advance and see how it goes. Going to step down another. 003 on idle restrictions too and see how it goes.

Thanks.

 

Heres an example of the software for my box. It only pulls timing so gotta think backwards when programming.

 

Ah ok. Hopefully that works out for you. I was able to set mine by using a small vacuum pump on the advance can based on the manifold vacuum, and I would imagine you could rig up something similar to test it on your sensor by pulling it out and plugging the hole.