Good call. I concur

 

Okay guys I have some updates for you. It snowed here pretty bad the past 2 days and its like 3 degrees out and my driveway is iced so I wasn't able to get the truck outside and started today, but I took some photos in my garage.

1. First of all I have a C4 Transmission not a C6. Some guy was helping me with my truck a while back swore it was a C6 so sure why not, but I looked at the pan today and it was 100% a C4 transmission pan. So I don't think that changes much, but I just wanted to let you know.

2. My oil is getting kind close to black after just 60 miles. I changed it about 2 months ago drove 60 miles and changed the spark plugs then too.

3. I am using Autolite 25 Copper spark plugs (I bought the same ones that the vehicle originally had in them). I can't find my gapper tool, but once I do I'll post what they are gapped at.

4. My Valve modulator is a push green stripe and it was bone dry inside the tube coming out of it so I am going to assume its not siphoning any transmission oil.

5. All the photos of my rockers, carb, trans, oil, etc. Last two pics are of the gauges I just finished putting in and my first time using vinyl, I think it came out alright.

 

That tranny output shaft looks awful rough (rusted/pitted), and the tranny seal looks dried and cracked. But on the good side the dash looks great! And the inside of the door is very nice. Is that the temp sensor on the manifold (below the dist.) the wire is missing whatever it goes to.

 

Just a question that might eliminate the carb. If you run your idle mixture screws all the way in does the engine still run? The reason I ask is that the power valve in an over the counter Holley is a 6.5. When you run a modified cam you have lower vacuum and it could require a lower value power valve like a 5.5 or even 4.5 to keep it from opening at idle causing a very rich idle mixture.

 

 

If it raises the idle with the screws all the way in you definitely need a lower value power valve. Try a 5.5 first and I would also get a #31 squirt nozzle for the accelerator pump so you don't get a flat spot coming off idle with the lower power valve.

 

 

Most all Holley carbs I have ever wrenched on, has always had POWER Valve issues, a backfire can rupture the diaphram & then over fueling is sucked into manifold. Unburned fuel turns oil dark.

www . Holley . com has a good website to visit, technical & service info is good, some videos too.

Old holleys use to have a CORK jet plate to Body Gasket that deteriorated in no time, causing engine run issues, Hopefully your carb has the new style blue material gasket.

Sometimes Youtube have video that help showing how to get it fixed.
Internal carb circuits may be gummed up .
Good luck

 

Damn, I wish I had your guys mechanic knowledge. Reading these is almost like a college education...Love it.

 

Do you have a vacuum gauge? It is very useful in situations like this.

If you don't have one, get one. They don't cost much and are very useful for tuning.

 

Yeah I've been looking at their website they have some good resources there.

Right? my life would be so much easier haha.

Yessir the vacuum gauge results are shown in the 2 videos in the original post those results started this thread

 

Whoops haha. I totally forgot about that.

So what does the gauge do when you screw the screws in?

 

Honestly not much, it still bounces about +/- 5 in either direction. When I adjust the screws about 2 full turns or so it moves about 5 (still bouncing). I got my timing light yesterday, everything is just frozen here so I'm waiting for the temperature to come up a bit. Probably show you guys the timing results tomorrow and take off the carb and put the new 5.5 power valve in and the 121-31 squirters in as well.

 

The gauge should not be bouncing. And the only thing that causes a bounce is a disruption of standard air flow.

Carb adjustments and ignition timing don't cause irregular air flow. (Adjustments May very well be needed, but they aren't going to fix your problem)

 

I see, I did do a compression test and my results were between 109-119. A few people said my timing sounds retarded and 13mm said this:

Do you recommend doing anything else to get the needle to stop bouncing?