[stinky jinx]

What is your best guess at a base timing for a 350 chevy with a mild cam. air gap manifold. holley 670 street avenger. dougs shorty headers, electronic ignition and breaker less distributor. I am still having an off idle hesitation so I am just trying to dial this thing in.........jerry

[poncho62]

Try 10 degrees and if it pings on acceleration, back it off a couple.

[Frisco]

Doesn't anyone read the previous posts or go to the Knowledge Base. This question has been asked and answered forever.

By the way and off idle hesitation is more than likely carb related. Increase the squirters two sizes.

[stinky jinx]

Frisco
I knew this post would bring a reply about how many times timing had been talked about,and actually I did looked first, but as I am fairly new to this board I am somewhat unclear on how to look up a specific question. So if you or anyone doesn't mind, tell me how I would look that question up.

[Frisco]

Originally posted by stinky jinx
Frisco
I knew this post would bring a reply about how many times timing had been talked about,and actually I did looked first, but as I am fairly new to this board I am somewhat unclear on how to look up a specific question. So if you or anyone doesn't mind, tell me how I would look that question up.

OK. I type with two fingers so am a little slow.

Set your initial timing to 10 degrees with the vacuum hose dis-connected and plugged.

Now check your Total Mechanical timing. You are looking for around 34-36 degrees all in between 2500-3000 RPM.

Re-connect the vacuum hose. I prefer to hook it to the Full vacuum port.

You will probably have to lower your curb idle speed at this point.

Test drive the car. If when cruising in high gear up a slight incline you hear any pinging, drop the timing down 2 degrees and test drive again. If you do not hear any pinging you can probably increase the timing some.

I have a similar combo to yours.

350 Small Block, HEI ignition, Blockhugger headers, AFR 190cc 68cc chambers, aluminum heads, Comp Cam 280H (12-212-2), Edelbrock RPM Air Gap intake with a Holley 670 cfm Street Avenger, th350 trans with a B&M TransPak (street version), 8" Ford rear with 3.80-1 gears, P275/60-15 rear tires.
I run 18 degrees initial and 38 degrees Total mechanical all in at 2600 RPM and have the vacuum advance hose connected to the Full vacuum port. Starts excellent, absolutely screams when required, cruises at around 3250 RPM at 65 MPH. Runs on regular gas due to the lower than optimal compression ( about 9.1-1).

You can probably do a search by typing in "Chevy timing"

[Frisco]

Originally posted by Frisco
Doesn't anyone read the previous posts or go to the Knowledge Base.

Wow!!!

I apologize for this posting!

Out of curiosity I typed in "Chevy Timing" in the Knowledge Base. Lot of stuff came up. Many links no longer work. Nothing of much value to be found (at least on the first two pages of links.)

Same thing when just going to the Engine Section in the Knowledge Base.

Someone needs to clean up the links.

In the meantime, keep asking the questions and we will try to answer the best we can.

[Jmark]

Originally posted by Frisco
I run 18 degrees initial and 38 degrees Total mechanical all in at 2600 RPM and have the vacuum advance hose connected to the Full vacuum port. Starts excellent, absolutely screams when required, cruises at around 3250 RPM at 65 MPH. Runs on regular gas due to the lower than optimal compression ( about 9.1-1).

I have 34 degrees on mine, base+mechanical and NO vacuum advance. Yesterday I had my son with me delivering an entertainment center and got into it pretty good on the freeway and he said it was pinging like crazy after it hit third under load. I'm on regular too and am concerned as to why its pinging! I"m supposed to have 9.1 or very close. The engine was getting a tad on the warm side, so I guess that may have contributed to it, but it still bugs me.

[Frisco]

Originally posted by Jmark
I have 34 degrees on mine, base+mechanical and NO vacuum advance. Yesterday I had my son with me delivering an entertainment center and got into it pretty good on the freeway and he said it was pinging like crazy after it hit third under load. I'm on regular too and am concerned as to why its pinging! I"m supposed to have 9.1 or very close. The engine was getting a tad on the warm side, so I guess that may have contributed to it, but it still bugs me.

I'm not sure what to say. Vehicle weight (load on engine) may be a factor. My little truck weighs 2660 pounds. I also have aluminum heads that may be a factor. You mentioned that the temp was a tad on the warm side. How warm? That could be the major factor if you have steel heads. My temps stay between 180-190 under almost any driving conditions. I did get up to 200 degrees once when pulling a very long uphill grade from South Carolina to North Carolina doing 70 MPH. People in this area know the grade as Saluda Mountain. Ignition could also be a factor as can the plugs you are running. Are you running lean at upper RPM's? You can check this by running hard into the upper RPM range, immediately shut off the ignition and shift into neutral. Come to a full stop. Now check your plugs. If they are white or light grey you are lean. Checking your plugs at idle is only showing how the idle circuit is running.