What timing curve on your Chevy sb?

[Ornberg]

I'm just curies about what timing you Chevy guy run your small block. Now when the gas price is going sky-high I must concern about to get as much mile per gallon as possible but without to sacrifice power. The gas price here in Sweden is 5 Dollar per gallon. :x  I run 16 initial and a total of 36 in my 327, all in by 3200 rpm. But I didn't take the time to really test other combinations. I know it's a trial and error to get it right. I have the original weights with medium spring in my Hei. I tried some Mr. Gasket weight but don't like them. Somebody might have some advice on this?
My 327 are a stock 300 hp with weiand Stealth and Holly 600 vacuum.

Per

[Dave]

I'm just curies about what timing you Chevy guy run your small block. Now when the gas price is going sky-high I must concern about to get as much mile per gallon as possible but without to sacrifice power. The gas price here in Sweden is 5 Dollar per gallon. :x  I run 16 initial and a total of 36 in my 327, all in by 3200 rpm. But I didn't take the time to really test other combinations. I know it's a trial and error to get it right. I have the original weights with medium spring in my Hei. I tried some Mr. Gasket weight but don't like them. Somebody might have some advice on this?
My 327 are a stock 300 hp with weiand Stealth and Holly 600 vacuum.

Per

36 total is good . I like total timing . The initial dont mean squat as far as im concerned.  I was always told to do the total and hell with the initial. If its right the gas milage should be as good as it gets with the total.
Dave

[EMSjunkie]

I agree with Dave, total timing of 36-40* should be
good for a SBC.

My coupe is set at 38*. it seems to like it there.

I agree with the fuel mileage, but fun per miles is important too.  


Vance

[HOTRODSRJ]

I'm just curies about what timing you Chevy guy run your small block. Now when the gas price is going sky-high I must concern about to get as much mile per gallon as possible but without to sacrifice power. The gas price here in Sweden is 5 Dollar per gallon. :x  I run 16 initial and a total of 36 in my 327, all in by 3200 rpm. But I didn't take the time to really test other combinations. I know it's a trial and error to get it right. I have the original weights with medium spring in my Hei. I tried some Mr. Gasket weight but don't like them. Somebody might have some advice on this?
My 327 are a stock 300 hp with weiand Stealth and Holly 600 vacuum.

Per

Well, I hate to disagree with the others.....but while total is important for power production ...so is initial and certainly vacuum advance for milage and drivability.

See my diatribe here.... http://www.chevytalk.org/threads/showflat.php?Cat=0&Board=UBB64&Number=1105501&Searchpage=1&Main=1105264&Words=%26quot%3Bcamaros.net%26quot%3B&topic=&Search=true

Good reading on other timing aspects

[Ornberg]

Steve
Thanks for that link, real interesting reading. I see that the guy from Norway have a pretty heavy car with not so much of gear ratio  (2.73) In my own Buick I got a poor 2.56 ratio in a fairly heavy car. Is this a factor to consider when I set my timing curve?

Per

[Bruce Dorsi]

In my own Buick I got a poor 2.56 ratio in a fairly heavy car. Is this a factor to consider when I set my timing curve?

Although I'm not Steve, I think that your gear ratio will influence your timing curve in two ways.

With that ratio, your cruising rpm will probably be well below the 3200 rpm recommended for full centrifugal advance.  ...So, if you are running centrifugal advance only, your timing is probably too retarded at cruising speeds.

You did not mention if you are running vacuum advance also, or just centrifugal advance.  .....Vacuum advance hooked up to manifold vacuum should help gas mileage.

The weight of your car and that gear ratio will induce more of a load on the engine, decreasing manifold vacuum, so a vacuum  advance may have to be adjusted accordingly.

[Ornberg]

The weight of your car and that gear ratio will induce more of a load on the engine, decreasing manifold vacuum, so a vacuum  advance may have to be adjusted accordingly

Yes I have Vacuum advance hooked up to manifold and restricted to about 10 degree. Maybe I want to have a "faster" mecanical advance curve as for example 36 degree by 2500 rpm or get moore vacuum advance?

Per