Timing Engine - To What Degree - Lateral-g Forums

camaro1969 · #1 04-30-2010, 02:00 PM

I am timing my SBC, since it has a lot of aftermarket parts, i cant really go to a spec book and see what i should time it to. I was hoping to get you thoughts.

Engine specs below

SBC 350, Th350 Auto, 12 bolt rear 3.07 gears, 15 inch bfgoodrich t/a radials...

Cam:
Comp Cams #249-CL12-242-2
Xtreme Energy XE268H Hydraulic Flat Tappet Camshaft
Lift: .477''/.480''
Duration: 268°/280°
RPM Range: 1600-5800

Other:
1479H keith black pistons .30
139 piston rings
CLE-CB663P rod bearings
CLE-MS909P main bearings
CCA-817-16 compcam lifters
SLP-260-1000 gasket kit
CCA-981-16 compcam valve springs
CCA-1412-16 compcam roller rocker
ARP-134-6003 arp connecting rod bolt
Non electronic distributor or electronic ignition

ProdigyCustoms · #2 04-30-2010, 02:48 PM

We got everything but cylinder head info which is probably the most important info of all.

If it has factory heads, I would time it at 3000 RPM at 38 and then blip the throttle up from these and make sure it is all in at 3000RPM. And then I would see where it is at ldle (14-16 or so it should be)

If it has killer aftermarket heads it may like less timing, mabe in the low 30s.

ccracin · #3 04-30-2010, 08:18 PM

I think Franks got it for you. If it's not all in by 3500 for sure work on it. I like 3000 with good gas, but will take 3500 with crappy gas. My .02. Good Luck.

Vegas69 · #4 04-30-2010, 08:29 PM

My new engine made the best power at 34. I'd error on the side of caution until you chassis dyno. 34-36 total and you won't burn it up.

camaro1969 · #5 04-30-2010, 08:45 PM

factory steel heads..

since i have a rowdy cam, should i be idling aroud 18-19 btdc?

When i have it too far advanced, my flexplate kicks back, and has already ruined one starter!

My vacuum advance on my distri is plugged for now, until timed

so at 3000 RPM around 38, i should have an idel around 15?

Vegas69 · #6 04-30-2010, 08:49 PM

Total timing is your main concern. If it has a vaccum advance, you need to detach it from the distributor and plug in off. You need to rev it until it quits gaining advance. Changes can be made to initial timing if you can't achieve a clean idle or have a stumble. I'd go 34-36. More is not always better.