i installed a howards 488 lift cam, 224 duration. i did the valves adjusting my self putting a half turn of preload on them using the ec/io or is it eo/ic. cant rember the order

 

Are you using the stock timing marks, or have you put a degree wheel on the crank to determine true TDC in relationship to the new cam? You can't use existing timing marks to time a cam that doesn't line up with those marks.
Also you might try pulling the valve covers after warming the engine up and recheck the valve lash. Sometimes the lifters pump up and you end up tighter than what you had at cold lash. I like to break a cam in at zero lash without the preload and then readjust after breakin. I actually like less than 1/2 turn preload, and prefer to be closer to zero lash to avoid valve issues.

 

yes iam using timing mark on balancer and the timing pointer that was on the car. so if the headers are getting hot then i should advance some or retard some?

 

how is your Carb mix? Too lean can also cause headers to turn red. Your cam is not a big and bumpy one so you should be OK with somewhere around 5-7° inital timing at idle with the vacuum advance unplugged. That should be good for idle and starting the engine. After that in the higher RPM ranges you adjust the timing with different wieghts, springs and Vacuum advance modules or an adjustable VAM. Adjusting the static timing while the engine is running at higher RPMs can throw off the idle advance making the car hard to start.

Valve adjustment is also key here, as others have said. I like to preload chevy valves with 3/4 turn after 0 lash. Dont try to find 0 lash by twisting the pushrod, friction is not the determining factor. If you can move the pushrod up and down then there is lash once you tighten the nut enough to remove all up and down movement then 0 lash has been achieved, any more is preload. Since you have the intake on I would advise adjusting the valves per cylinder at TDC, and not use the old 1/2 now 1/2 later method.

once you know your valves are in order and you get a good static timing set then you should be able to play with the advance mech and get the right settings for your engine. Make sure you have good carb settings first or you will once again be chasing your tail.

Massey

 

i think the valves are adjusted okay. the carb was set pretty good before i redid the top end. so i think i just have to get the timing a little better.

 

Is this the same cam as before with the carb? If not then you wil have to adjust the carb to the new cam. It is kinda like tuning a new computer controlled engine, any time you change the internals of the engine you need to change the fuel and timing needs of the engine to match. If you put a larger cam in the engine than before then you will need to give a richer mixture on the carb to compensate for the added air that you are feeding the engine. Depending on the type of carb you have you may also need to change the metering characteristics of the carb for off idle and WOT performance. This all goes hand in hand with the valve adjustments and timing as well.

Massey

 

Your headers were getting red from too much advance. A small block Chevy wants 34-36 degrees total timing, no more. 45 was killing it. Set your initial timing and leave it alone. You don't really need to disconnect the vac advance to set initial timing btw, as there isn't any ported vacuum at idle, but do it if it makes you happy. Those instructions are a carry-over from back in the pre-smogged engine days when the distributors were connected to full manifold vacuum. Your overall total timing is adjusted mechanically by the distributor. To change that, you need to fiddle with the weights and springs that are beneath the rotor. You don't mess with your initial timing to try and adjust the overall timing.

 

this motor doesn't have any smog stuff on it! does that mater at all? so intial timing around 10-12?

 

No that doesn't matter. The pre-smog part I was referring to is how today's distributors (aftermarket as well) are set up to run on smogged engines. The original specs for your engine was 0 degrees initial. Try starting with 6 and see how it performs. Listen for any pre-detonation ping while the engine is under a load, and back off the timing off a couple of degrees if it does. If all was quiet, give it another 2 degrees advance instead and see/listen from there.

 

In all the engines I have worked on and built I have found that a SBC is happy with a static timing of 5-7° maybe up to 10° for a bumpy cam.

Why do you want to run so much advance? It is not going to make the engine perform better, it may seem to but like the article said you cant get an engine tuned right with poor settings. Everything must work together from the carb to the timing.

Massey