Taking the 4 degrees of retard out of the distributor?

[hinkv10]

My truck attracts a fair amount of attention and I got to talking to a local guy who is a sqarebody nut. One thing he mentioned was taking the 4 degrees of retard out of the distributor. Told me we could do it right in the truck and should take an hour or so. Take the distributor cap off and cut a slot in something and it would free up 10 horsepower. Anyone heard of this?

 

[Boone83K10]

no...

 

[350runner]

BS, just get the center plate and weights from a 80s suburban. They are stamped 375/ 41
Google then and you will see what i'm talking about

 

[Jims86]

Nope...dont do it. especially if you have tbi
if you have an old school distributor, and change the weights, or get an adjustable vac advance.
If TBI, re program the chip.
Dunno why you would want to do it at all, but if you do, do it right.

 

[foamypirate]

Sounds like that guy had 4 degrees of retard added to his brain...

 

[Driver4r]

LOL, just advance the cam 4 degrees and youll see improvement.

 

[hinkv10]

Yea, it seemed kind of strange to me too. I mentioned the fact that I could just adjust the timing and advance it 4 degrees and "it would do the same thing". He tried to explain it as it wouldn't help at low rpms before the vacuum advance kicked it.

The guy is an old racer so I don't totally dismiss everything that he said. I just had never heard of anyone modifying a sbc distributor to get the "retard" out.

and I have an 87 but its been switched to carb.

 

[Driver4r]

Get another dist(junkyard special) and let him do it. See how it is, then post pics lol.

 

[350runner]

Letting someone mess with your engine timing is like rolling dice.... Hope he don't got bad luck.

Center plate/ weights
375/41

 

[chengny]

I am not into performance so this subject is not all that familiar to me but I think this is the basic concept:

Installing a center plate with the 375 cam contours, a set of 41 fly-weights (and often a set of lighter fly-weight return springs) is actually what is commonly referred to as "re-curving" a distributor. A recurved distributor is intended to more quickly advance the timing using the centrifugal advance mechanism. This allows for somewhat quicker acceleration during periods of heavy load change. It will not increase low end torque.

A 375 center plate has the cams cut in such a way that it cranks the timing up (advances it) faster during an initial heavy load application - i.e. - WOT.

When you first start to accelerate, for the first few seconds, the timing is controlled only by the mechanical advance part of the distributor. That includes the center plate, fly weights and springs.

The vacuum advance acuating diaphram is attached by linkage to the center plate, but it is out of the loop during conditions of WOT. It does not come into the picture until the throttle is no longer wide open. At some point sufficient vacuum is developed in the intake system to stroke the diaphram and linkage of the vacuum advance system.

Then, until the throttle opens wide again and vacuum drops, the actuating linkage of the vacuum advance overrides the mechanical advance and continues to regulate degree of spark advance.

As long as intake manifold vacuum remains high enough, the vac advance stays in control. The function of vacuum advance is primarily one of fuel economy.

 

[350runner]

Long post not to b into performance??? yes it will help from bottom to the top... Then you add that vac advance.(I have the Accel vac can) simply put b4 I added these 3 items + a qjet to my list I couldn't burn rubber even power braking.after.... Well

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Not power braking.

 

[Jims86]

LOl...He may not be "into it", but he knows his ****!