Currently i'm in the process of putting in a new cam. I was wondering if anyone out there knows if my cam is "pre-advanced" . Its a summit cam (sum-1104). I want to advance it to 4º but i dont have a degree wheel and dont want to shift the curve too far. Id really appreciate a response soon cause i just got my old cam out and im about to go back into the garage. THANX

 

What are the LSA and LCA angles? Have the cam card information?

 

im not going to lie about it i dont know a whole lot about what all of it means so im just gunna type out the angles on the card:
cam timing @0.05 tappet lift , opens IN/EX 3ºbtdc/51ºbbdc, closes IN/EX 41ºabdc/-7ºbtdc, max lift IN/EX 109ºatdc/119ºbtdc. duration 224º

 

It appears by comparative analysis of similar factory cams, the cam you have is already advanced over what a factory SBC would have had after 1970.

Advancing it would probably be O.K., but it's already advanced by about 2° over what a factory cam would be.

This is all presuming that both the cam and timing sprockets are keyed and dowelled correctly. The only real way to check that is with a dial indicator, piston stop, and degree wheel. If the heads are off, you can forgo the piston stop and use the indicator and degree wheel to find true TDC of the crank.

 

If you install the timing gears properly the cam will already be 5deg advanced in the motor. Further advance is not nessessary. if its going in a 305 you'll want a high rear gear ratio like 3.73 or 4.10. 4.10 is not too much. Don;t be shy.
If using an automatic trans ( th-350) a 10" "3500stall" would be best.
A typical "3500stall" rated converter will give you about 3200 actual stall behind a 305. (just right for this cam) Most converters are rated for stall behind a 350. A 305 will give less actual stall.

You'll also want to rework the distributor mechanical advance curve to allow more initial timing at idle with this cam but limit mechanical travel to achieve 34-36deg at hgh rpm.
The more initial the better. the practical limit, is the starter motor's ability to crank the motor over when its hot.
16 to 24deg initial is good 34-36 total. 15 deg vacuum advance at high cruise.
From the summit catalog , Summit # BMM-20425 Torque converter is just right for a Th-350 trans.