just as it says
when i set my timing on my carbed 305
what is the stock timing setting
how far can i go?
i would like to keep running on 87, but i dont mind 89 octane
so what should i set my timing too?

 

The factory setting is 6 degrees advance. If you're still running a computer controlled distributor, you will need to disconnect the est wire to check base timing.

Every engine responds a little differently to timing. If your combustion chambers are not too carboned up, you can run 8-10 degrees base.

www.geocities.com/dzperf

 

thanks, when i changed my head gaskets there was very little carbon build up on the pistons, plenty in the egr

what kinda horsepower gain would i see from that?

 

Not really a gain, just shifting the rpm where peaks are made, it may free up some power already there. Advancing improves low end, retarding top, but to find the peak, usually advance it until it begins to knock(ping) and back it off 2 degrees.

 

90rocz - I think you're confusing cam timing with ignition timing. Optimal ignition timing is critical to making horsepower. The theory of advance till it knocks does not work on computer controlled motors. The knock sensor will pick up a knock that you can't hear. Once it detects knock, it will retard timing. You will lose power.

 

Hitech5, thanks, I was thinking cam timing on the powerband, sorry.
But, If he has access to a scan tool he can monitor the Knock counts or Knock retard degrees, and take it to the edge. Ofcourse the ECM should hear knock before you do, but this is not always the case. If you see KR on the scan, back it off 2 degrees at a time, factory chip. With an aftermarket chip, stay with the factory 6*BTDC.
When I was stock, I added 2* at a time until I got KR at 10*BTDC, then backed off to 8*...later I added a Hypertech Therm-O-Master to get more timing.

 

cant i disconnect the knock sensor?

i may have that problem already, see, the wiring for the knock sensor and the wiring for whatever coolant sensor is on the passenger side head, use the same type of connection and the wiring can reach either sensor so i'm not sure which wire connects to which sensor but i'm sure i'll find out on the maiden voyage

if i use 89 or 93 octane can i further advance the timing? or does the knocking at 10 degrees btdc happen regardless of octane?

also since we're clear this is ignition timing, how much horsepower can i expect to gain?

(its ok 90rocz i made the same mistake with reverse flow and reverse rotation )

 

Ofcourse increasing octane will help some but advancing too much means you'll be igniting the mix way before the piston reaches top. If you advance it past the "lag time"(time it takes for the explosion to develop enough to exert force on the piston), you'll beat a hole in your pistons.
Especially if you disconnect the sensor, your computer won't pull out timing when detenating(or beating on your pistons).

 

i was just wondering if i disconnect the knock sensor i can advance the timing 2 degrees ata a time till i hear knocking and then go back

but i have a bigger problem
i feel like an idiot

i rotate the engine to get the timing mark on the balancer to match up with the little viewing hole that seems to represent tdc for cyl 1
then i put the distributor in and walk it till the rotor is where i plug my number 1 spark plug wire
then i plug the rest of the wires
18436572

i go to start the car and the motor spins pretty slow and doesnt fire at all
i switched the wires thinking i'm 180 degrees off still nothing
i know i'm getting spark because the inductive timing light turns on
i know its not a fuel problem because it wont even fire with starting fuel

so it must be me, i have to be doing something wrong

i cant rotate the motor by hand to get to tdc
so i use the starter to turn the engine till it gets to the unreadable notches
and no fire

 

Ok, you need to re-establish TDC.
You can't really rely on the balancer mark b/c sometimes the outer ring slips when the rubber elastometer gets old.
You can turn by hand with a breaker bar or large ratchet, just go slow and allow the cyl pressure to bleed off as you turn.

1)Pull the drivers' side valve cover.(No#1 is drivers' front cyl, ofcourse...)
2)Rotate the engine until the "Intake" valve closes on No#1 cyl., then the very next time the mark comes to ("0") it should be at TDC on the Compression stroke.
((Intake valve is even with the Intake Runner, Exhaust valve is even with the Exhaust manifold port.))
TDC comes up to the bottom of the largest "V" (= 0*)in the damper pointer.
3)Verify with a small screwdriver, that the piston is at "TOP", you won't hardly be able to get it in the spark plug hole if good.
4)Make sure that the rotor button is pointing to the #1 plug-wire terminal.
5)Make sure No#1 wire goes to No#1 cyl.(K.I.S. rule, Keep It Simple...verify everything...I know you probably did this a hundred times, but...)

 

i have no problem trying again and again

i tried rotating the crank with a breaker bar before it didnt work
the tranny was in neutral the spark plugs werent in and i pulled with all my might and the center bolt just stopped turning and i went nowhere

i'll try again and i'll try holding it there, but i dont see why i need to bleed pressure if the plugs arent in and the crank doesnt even begin to rotate

i just keep hoping its something really simple that i forgot or something

 

Hate to say it but sounds as if motor may be locked up. Did you recently rebuild it?

 

i blew a head gasket so i freshend it up
milled the heads changed the clutch while i was at it

i was able to turn the motor by hand when i tried to take off the flywheel with the heads off, i only turned it about a quarter turn by hand, then i turned back

while i was there i changed my oil pan gasket, exhaust and intake gaskets
the motor looked practically new,

and the motor does spin when i use the starter, just slow

then engine did run after i blew the head gasket, i just had alot of white smoke and milky oil, it spun very slow when starting at that time too, i believe because the crankcase became filled with about 2 gallons of water/oil engulfing the crankshaft

 

Oh, "T5"....you need to press the clutch to rotate the motor by hand...sorry, I missed that before..
Motor should be fine...

 

the tranny shouldnt be a problem if its in neutral should it?

i'll get a chance to try again tomorrow,