Distributor Vacuum Retard Delay Valve

Loves302Chevy

Loves302Chevy

"One test is worth a thousand expert opinions."
1982 CLF 305 MT Emissions Decal 2.jpg

from 1982 305.
Look at the DISTR VAC RETARD DELAY VLV (purple arrow at center).
When I convert my 84 TransAm from E4Me Q-Jet to M4Me Q-JET (removal
of CCC computer control), I need to connect the vacuum advance canister on
the distributor to a vacuum source at the carb. I know that this DELAY VALVE
in conjunction with the DISTR TVS (distributor throttle valve switch) is supposed
to not allow vacuum advance from happening until the engine warms up.
My question is, do I really need this, or was this just done to get the car to pass
emissions at the time. I believe that it will not hurt anything if it is connected to
a "ported" (above the throttle plates) connection, just like it was done in the past.

Here is my STOCK decal:
1984 XJW 305 H AT Emissions Decal.jpg

This one is clearer to read. The only difference is the dual-snorkel air cleaner.
1985 UNC 305 G Emissions Decal.jpg

I will also be removing the air pump, air injection to headers, EFE, EGR, and VAC sensor.
I will be keeping the Charcoal Canister & Control Valve, Purge TVS, Tank Pressure Control
Valve, PCV, and Thermostatic Air Cleaner. I have already figured out how to connect those
to the manual carb.
 
Connect to Ported Vacuum on the Q-Jet Carb Mike.
Throw that Delay Valve away.
 
VenturiVacuum01.jpg
 
You have to be carefull and not give the 334 ci SBC Too much vacuum advance.
Lead to High Speed Detonation you can't always hear.
Like Cruising down the Highway 75-80-85-90-100 mph steady state.
Typically 8-10 degrees additional advance is Ok.
Some engines tolerate 20-24 degrees Vacuum advance.
Namely Olds V8.

SBC Likes Vacuum adance on.the street.
Part throttle is Snappy.
Fuel economy improves.

A real effective efficient ignition system does away the need for Vacuum advance in many cases.
 
100% Correct. My rod bearings and the big ends of the rods showed signs of detonation -
even though I never heard a thing, and I was listening for it. My car did not come with a
knock sensor. Previously I had an aftermarket computer in the car that was adding an
assload of advance - maybe 60 degrees total. The engine seemed to like it, or so I thought
at the time.
This time around I want to add a knock sensor just to flash an LED to alert me to knock,
and I can back off on the timing manually. But I can't find any of that from a used 84-86 F-Body.
I need the knock sensor, ESC module, and associated wiring and connectors for that circuit.

I have MSD 6AL ignition in the car already.
 
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A Long Time ago now, MSD Ignition products made a Small Stand Alone knock sensor kit.
They supplied a knock sensor and wiring. The Control head readout was a simple bar graph with an audible beeper alert.
Not many ever bought them. It was around till 2005.

I looked last year for something similar .
Just a Knock Sensor alert system is made my CASPER ELECTRONICS IN MUNDELIEN ILLINOIS .
THEY CATER TO THE BUICK GRAND NATIONAL & GNX GUYS.
ITS VERY OLD SCHOOL NOW.
 
My 1987 Corvette Tuned port engine has The seperate ESC System.
I have tried using other knock sensors from different year Corvettes. And different year ESC Modules.
Just led to poor performance and terrible audible knock.

Went back to stock 1987 Corvette Hardware.
My conclusion was Ethanol gasoline is bad for max WOT Performance .
I had to wait several years but a Phillips gas station near my house sells True untainted 100 % 91 R/M 2 Gasoline.
My Corvette & 1963 GP With Olds 425 10.25 :1 static compression Loves the Good Pump Gas.
 
Checking it out now. I was aware of the MSD one - couldn't find that one when I looked a few months ago.
 
The Best way is the Old School Way Mike.
Read the Spark plugs under a magnifying glass Eye Loop.
Read the plugs under all driving conditions .
Tune away for best results.
 
I was on Corvette Forum and hung out with one of the Very Best EFI Tuners ever.
Dave Dahlgren.
Eccentric like us.

E10 Gas has a different Stochiometric ratio than most think....Its not 14.7:1.
14.7:1 Is for 100% pure untainted Pump gas.
E10 ETHANOL IS 14.3 :1 STOTIOMETRIC CORRECT .
 
I remember now. The sensor must be matched to the bore size of the engine.
That is why I want to modify the GM setup. The aftermarket gauges don't ask
anything about the bore size you are using.
The GM ESC module also filters out the unwanted frequencies so that it can look
at only the frequency of the knock.
 
The old Grumpy's forum had a way to send you a private message.
Is there a way to still do that?
 
Ethanol plants here near me & in Iowa.
We grow Corn to make Chicago gasoline .
KRAZY SHIT.
 
Yes. PM Still works here on Grumpys.
The usual group daily, seldom use it.
 
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