Fire Mission:

Just respond with your current engine, spark plug gap, ignition type and timing setting.

Looking for a trend, if there is one.

6-cylinder folks need not respond to this one, thanks.

Mine: 428, .050 gap, HEI, 11 before TDC.

455
7M5 Heads (about 8:1 compression)
Cam specs unknown (seems pretty big though, or at least lots of overlap)
0.50"
HEI
20° BTDC initial (low comp, big cam)
36° BTDC total (w/o vacuum) by 2600rpm
Vacuum advance hooked to manifold (adds about 14° at idle)

406, HEI w/MSD 6AL, .045, 12* initial/24* mech/total 36*@2200(vac can limited to 10*)

468
MSD box
MSD ProBillet dist.(no vacuum advance)
16 degrees initial
34 total in by 2500
NGK plugs @.040

455 (462)
E-brock heads
Custom ground roller camshaft
Mallory Unilite with Vacuum advance and MSD HiPo round oil coil
91 octane pump gas
Autolite AR 3932 plugs @ .040
Total timing 36 degrees (set via dyno testing)
Inital timing 8 degrees (found via timing light)
488.9 HP @ 5100 RPM
574.2 ft/lbs at 3700 RPM (lowest point the dyno would measure)

400 (68)
16x Heads
Stock Cam
0.45"
Pertronix and Flame thrower
12° BTDC initial
30 something° BTDC total altho I think my vacuum valve may be hooked up screwy as it runs better cold...

I think I will do a cold and warm to compare on this thread!

68' 350 ci 4bbl

A/C Delco 1 heat range hotter than stock .045 gap

MSD 6A

HEI with MSD Blaster Coil

12 degrees initial, 36 total

400 engine
.045 gap
HEI ignition
14 degree initial, 12 mech, w/vac 46 at 2500 rpm.
I know.. the timing seems off, but all the mech I can get... and it runs good.

Hmmm, starting to see a few things here....

1 - There are no set numbers, rules or specifics that work for everyone.

2 - My timing is below norm, and my gap is above norm......

For optimun settings for your combo - I highly recommend having it dynoed. I'm a believer now.

There is a lot of experimention involved in getting one of our non-computer controlled motors to run at it's peak.

461(400 w 455 crk)
6.800 rods/SRP flat's/0 decked
87cc E-heads
RAIV cam/1.65 rkrs
RPM intake/850 carb
1.75 pri hddrs/3.00 exh
MSD 6al plus/blstr III/gutted HEI
38 total(have to check exact setting)(wants 42 total)
NGK #8 @ .035

Tha various combos are too different to have the same ignition requirements.

aluminum heads...Iron Heads...10.5CR...9.0 CR...Quadrajet...Holley...big cam...small cam... lots of variables.

Agreed BB (Greg), but I would have thought all our HEI spark gaps would have been within .010 of eachother. And I would have figured initial timing would be within 2-3 degrees for us all.

This is not the case for some reason. Not even close.

I was reading a tuning tech article last night that said that mucle car era high compression Pontiacs liked 30* total timing because of refomulated gases. Everybody I've ever heard from said 36 to 38 is what they run.

http://www.webrodder.com/article.php?AID=519&SID=60&CID

Maybe my large spark plug gap is what is causing my smelly exhaust problem.

Car runs great, no smoke or anything, but exhaust does stink until fully warmed up.

I use 045 gap on my HEI.

They all stink until they're warmed up...check to make sure your choke is adjusted properly.

my sh!t don't stink

If you're gap was too big for your ignition system, you'd be getting misfire, which you'd probably notice.

Originally Pontiac specified a 0.060" gap with HEI to maximize combustion efficiency. However, over time as the electrode wear increased the gap, the spark could no longer jump it. Since this was happening a little before normal tune-up intervals, they elected to dial it back to .045".

A good working HEI should easily handle the .050" you and I are running now.