Tuning question!

[mikep]

which pump did you end up going with? It sounds like you need to work on your advance curve though. If you had 12 degrees at idle and 55 at full advance then you have 43 degrees total. That doesnt sound like any mallory distributor I have ever seen. Usually they keep them in the mid 20's range. What model is it? For optimum performance you want more like 20 degrees at idle and 36-38 degrees full which is only an 18 degree or so spread although you may be able to get by with upwards of 42 degrees total timing if yours is the typical 8:1 compression late model 454 . A lot more advance at idle will take care of a lot of slugishness problems especially on lower compression motors . If I were you I'd disconnect the vacuum advance for now and shoot for around 38-40 degrees at full advance using the mechanical advance alone. Put the mallory springs back in it.

[HvyChevy454]

what i ment by stock springs i ment the springs that were originally in the mallory distrib when i bought it. i cant find any place on the box that says what type of mallory distrib it is. but it did come w/ xtra springs and a instruction sheet for advance curve settings.ther are 3 sets that are listed by curve engine RPM
1st one- start 400 total 1600
2nd - start 600 total 2800
3rd - start 600 total 4000

i ended up going w/ a holley blue pump 110gal/hr, guy cut me a deal at $100

[HvyChevy454]

to check the full total advance would i use 12degrees as my starting point or would i use top dead center, also to check total should i leave the vacuum advance off to check it? my dad abd i are at odds about this now

[mikep]

This is what I would do if I were you. Disconnect the vacuum advance unit. Plug the port. Using an advance timing light turn the dial to 38 degrees. Run the motor up to 3000 rpm and and turn the distributor until the timing mark on the balancer is at the TDC mark on the balancer tab. Lock down the distributor. Your'e done. The extra low rpm advance will really pick up throttle response. Also play around with the springs. The lighter springs will bring on the advance a lot sooner and pick up your throttle response as well . If you get into a bit of pinging then put in the middle grade springs. With your gears dont puut in the heavy springs though or you'll never get into full advance..

Have fun with that blue pump. Ive had cars that the blue pump was louder than the motor. You paid too much for it. Shop around next time. Summit Racing will get one into your hands in a few days for a lot less.

[HvyChevy454]

its just my luck w/ buying stuff... dang...!