Timing a non-stock 350
When timing a chevy 350 that is not stock (aftermarket cam, carb...), what is the best way to determine what your timing should be at? Is it best to set the timing, and then tune the carb, or vice versa? Is there just a set timing, or standard that all small block chevy's work on?
I ask because the engine is running rich, the carb loads up when sitting at the light, and sputters on takeoff (unless I baby it). It also smokes a little when idling. I assume my timing is off, and while the holley 750 is new, it may need to be tuned. Any info is appreciated
post all the specs of your motor that you know of.
Cam, carb model list # manifold etc etc.. I can recomend a good set up to start with
and you can fine tune that to get it just right.
A racey cam needs specific non stock setup for the carb and distributor.
It will not "load up" once dialed in.
The more specific info you give the better I can Zero in on the tune for you.
be prepared to modify the distributor curve and change a few things in the carb
( power valve etc)
Its not that hard
a Stock low stall converter will not work with a racey rough idle cam.
Here ya go:
sbc 350, .060 over
speed pro cast flat top pistons
63cc double hump heads (not the 2.02)
edelbrock dual plane intake
Holley 750 vac sec
lunati barebones cam #10001lk
Intake Duration at 050 inch Lift 214
Exhaust Duration at 050 inch Lift 224
Duration at 050 inch Lift 214 int./224 exh.
Advertised Intake Duration 280
Advertised Exhaust Duration 290
Advertised Duration 280 int./290 exh.
Intake Valve Lift with Factory Rocker Arm Ratio 0.443 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.465 in.
Valve Lift with Factory Rocker Arm Ratio 0.443 int./0.465 exh.
Headers, 2.5" exhaust pipes with flowmaster 40's
Stock gears in the back
TCI streetfighter turbo 350, Jegs 2300-2700 stall conv
I'm also using a hei distributor with an accell super coil, 8.5mm wires and ac delco plugs. I'm not scared to change things, I just really want my engine to be dialed in. I appreciate the help
That is not a radical cam at all and will not need any special mods to get it to run nice.
Timing 14 to 16 at idle 34-36 @ max advance. 12deg max vac advance at high vacuum cruise (hiway)
Carb 70-72 pri jet #21 metering plate or #80 sec jets.
6.5" pri power valve.
Good vacuum and near stock idle.
Make sure the HEI is getting a full 12v+ and the engine is grounded to the firewall.
Check the adjustment of the accelerator pump linkage.
.025 to .031" shooter.
You may have a vacuum leak.
Smoke: intake is sucking oil vacuum leak
Oil migrating up the PCV . valve cove baffling under the PCV.
common issue with aftermarket pretty valve covers- no baffling.
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