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Distributor installation help

1K views 3 replies 2 participants last post by  1981zapper 
#1 ·
I have purchased a PerTronix Flame-Thrower Billet Distributors with Ignitor III Module # D7100711 and PerTronix Flame-Thrower III Ignition Coil 44001

My engine is;
Big block chevy 427 bored .060,
-9:1 compression, the pistons are .010 in the hole
-Lunati Hydraulic Roller Voodo (.575/.575 Lift Duration @.50 221 int./229 exh) Lobe Separation 112 RPM Range: 1,800- 6,500
-I got approximately 165 PSI of cylinder pressure


I currently have a Summit Racing Blueprinted HEI Distributors #SUM-850001R and the engine pings under hard acceleration, I tried lowering the timing but it gets worse

so I have a feeling it might be the distributor, my new PerTronix Flame-Thrower Billet Distributors # D7100711 came with a variety of springs and limiters, can someone please help me set up this distributor, according to PerTronix the vacuum advancd can starts working at 7 and is all in by 16 degrees. It has 14 degrees of timing.

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#2 ·
I think your answer is here "the engine pings under hard acceleration". This is a pretty good sign that it wants more gas.

What is the carb?

For a Holley look at the number stamped on the side of the power valve that should tell you when it turns on in manifold vacuum pounds per square inch. General rule for starting the cut in tune is half the idle vacuum as a starting place and working around that. The other thing is the power jet size, if the valve comes on at the optimium time but the detonation in lowered though not eliminated larger power jets are in order. This can also be covered a little with main metering but doing that will burn too much fuel all the time which isn't good for the pistons, rings, cylinder walls and your wallet. The problem could also be too lean on the secondary jets so you could try starting here first and richening these up as this is easy to do, this won't affect cruise. If you're accelerating hard jet tubes may be helpful as the fuel moves away from the jets to the back of the bowl which leans out the secondaries with out the tube to chase where the fuel went.

For a Edlebrock/Carter or a Q-Jet power enrichment is the smallest diameter on the metering rod and the spring tension under the metering pistons or piston in the case of the Q-Jet. The game here is a selection of springs having different tensions most likely softer than what's currently in it. Or metering rods with a smaller diameter on the last step. The Edlebrock/Carter uses a fixed jet on the secondary that may need to be richer jet. The Q-Jet uses a fixed jet here with metering rods that move with the secondary air valve, again as on the primary side changing to a smaller diameter rod richens the mixture. changes to the secondary metering as with the Holley should not affect the primary cruise side mixture so stating here isn't a bad idea.

What's going on at WOT is a lot of heat and pressure in the cylinders so preigniiton and or detonation can become a problem. Excess fuel a ratio or ratio and a half beyond rich max torque is used to cool the mixture. The extra fuel absorbs heat as it changes state from liquid to gasious. The carb does not creat a gas out of gas. It may look like it does but in reality it creates a finely divided liquid mist, no state change has happened only fine division so the rules of physics and chemistry still apply as a liquid. When the change in state from liquid to gas happens then the gas laws apply and heat from the envionment in the mixture fine droplets and air is absorbed. Same as making steam in a tea kettle it takes a lot of heat to go from water to steam. Trying to solve the problem of huge amount of fuel needed to make steam (well actually the evaporation of alcohol from the water it was mixed with) for the making whiskey is what gave us engines in the first place when some people realized that all that heat energy could be used to push a piston.

Bogie
 
#3 ·
You bring up a valid point, I have only brought the motor up to 4500 RPM because its fresh build with only 75 miles on it, I have a Edelbrock AVS 800CFM, my spark plugs are black but I'm having a fuel issue especially on hot days, I'm having a vapor lock issue when its really hot out and my engine temperature increases I hope installing an electric fuel pump will fix this issue, but when its cool out and my engine temperature stays under 165*F my fuel pressure stays at around 4-5 PSI and if I step on it and bring it up to 4500 RPM then shifting it will ping but as I retard the timing it will ping more often even light acceleration and I feel loss of power
 
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