Need help setting the timing of a 305
 

Hi, guys! I just broke in a mildly built 305. Seeking some advice from the 305 experts, please... and please don't criticize my engine choice lol. I had a reason for going that route - the safety of a teen-ager.. ugh!

9.7:1 compression
Rebuilt 305 HO heads
Comp Cams XE256 full cam kit
Edelbrock Performer RPM intake
Edelbrock 1403 carb (500 cfm)
Stock HEI distributor
Stainless shorty headers

I used a stock harmonic balancer with the zero mark painted white but it has no numbers on it. Broke in the cam today - that went fine..

Straight headers right now and it's too loud to get a good feel for the timing.

I presume I need some timing tape... What initial timing should I start with and how much total timing should this engine need?

Thanks for any input!
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Re: Need help setting the timing of a 305
 

You'll need to experiment but here's some good info on figuring it out.
http://www.badasscars.com/index.cfm/...d=76/prd76.htm

Re: Need help setting the timing of a 305
 

There's no timing tab on the timing chain cover? And btw that 305 seems like it'll be pretty sweet... still be plenty o' motor for a teenager.

Re: Need help setting the timing of a 305
 

Is that a 350 cam spec or a 305 cam spec. May be kinda small for the compression

Re: Need help setting the timing of a 305
 

2x Is it possible that the timing tab on the cover got hit with a thick coat of paint hiding the numbers and lines? If you can't see any markings, there should be v-shaped notches of varying sizes to guide you. Leme see if I can dig up a picture.

Unfortunately you have open headers, so the ear method won't work so well. ;)

EDIT: There is a nice discussion and picture here of what you should be seeing:
http://67-72chevytrucks.com/vboard/s...d.php?t=151464
or maybe this one, depending on the style used in your engine:
https://www.thirdgen.org/forums/tech...et-timing.html
(see post #6)

Re: Need help setting the timing of a 305
 

My 305 had the timing mark at the 12 o'clock on the stock H/Bal Don't know if all were this way.

Re: Need help setting the timing of a 305
 

Thanks for the link..

The engine runs better the more throttle, but it is rough and wants to die pulling out of the hole. It is a stock/rebuilt TH350 with 1,750 stock stall converter.

I haven't adjusted on the carb yet. I need to get the exhaust on it and then I can tell more about it. It rattles my teeth at this stage.

Re: Need help setting the timing of a 305
 

Yeah, it has a timing tab. I think more than anything I am using an old-school race engine builder that is near retirement and isn't equipped to dial this timing in with a quality gun and is cranky about trying to getting the advance curved properly.

Re: Need help setting the timing of a 305
 

This one was 12 o'clock also.

Re: Need help setting the timing of a 305
 

I appreciate that!

And yes, you're right! These shorty headers open are deafening.. lol

Re: Need help setting the timing of a 305