i have a 350 with a comp cams 274 extreme energy cam, the lift is .488/.490. im having trouble getting the power out of the engine, i know it has got it in it, but i just cant unleash it. does anybody have a setup close to this and can tell me what's the best place to set my timing and carb at. can u tell me whats the best advance curve spring and how far advance or retarded i should be and where the carb should be set at. thanx.

 

Ignition timing should be 12 to 16 initial at idle
advancing to 32 to 36 at high rpm 3000 to 3500 rpm
( full advance may not occur till 4500/5000rpm on a stock distributor) Get an advance timing light or a balancer timing tape.
disconect vac advance while setting mechanical advance.
Vacuum advance should add 10 to 15 deg at high vacuum cruise.
Plug into "ported vacuum" on the carb.

The stock "out of the box" carb jetting should be fine to get you started but because of the lower manifold vacuum of your
camshaft, you'll have to change the power valve/power step up spring in your carb to keep the metering rods down or power valve closed at idle. Other wise you may have a rich idle. Usually a lighter (lower vac rating) spring or powervalve is nessessary.
Check the vacuum at idle (auto in gear) (manual trans rolling at low speed with clutch out.) select a PV or step up spring witha vac rating just below what u see on the vac guage.
EG: 5" manifold vac @ idle use a 4.5" PV.

Tell what carb and manifold you have and I'll see if I can help you with jetting.

 

i have a holley 600 single pump with a weiand stealth intake

 

Sounds like the only difference is the heads and carb between our motors.I run AFR's and a Speed Demon 750 DP.I run my base timing at 22 advanced,the Summit HEI in my Z has a mechanical advance of 14 additional degrees..giving me 36 total.I run medium springs in my curve kit along with the Crane adjustable vacuum canister.This seems to be the best timing for my motor.As far as the carb,it would be a whole different tune being that we have totally different size carbs.

 

Your "out of the box" jetting calibration should be real close.
Stock jetting for that carb #1850 is #66 primary and a #9 sec metering plate. Optimum jetting will be 4/5 jet sizes +/- either way.
Try a #39 or a #21 sec metering plate. They are a little richer. You can try different secondary vacuum springs
to see what works the best. If you now have the black spring,
try the plain steel spring ,purple, or yellow spring.
These open a little faster.
How is your exhaust system. Making horsepower is all about airflow so a good free flowing exhaust system is important.
Pay close attention to an increase in MPH at the end of a quarter mile test as this is a better indication of a power improvement than ET.
What heads are on your motor and what other mods?
Pistons, gear ratio, etc.

 

i have stock 76cc, 350/400 heads with 1.94/1,50 valves with some porting and polishing, i know i need knew heads, just gotta save the money, i have 9.0 dished with 4 vale relief, with a 3.08 posi but soon to be 3.42 with MSD cap, rotor and HEI coil with Accel 8.8 race wires and AC Delco R45TS spark plugs. I plan on putting 1.6 rockers on too when i get my new heads. The trans is a turbo 350 with a pretty decent shift kit but still gotta play with shift points a little i think, it shifts into second to low, it like falls on its face a little.

 

The carb/ manifold combo is not your problem.
The problem areas are in order.
The heads
The pistons and compression ratio
The rear end gears
The torque converter

The heads: Trash 'em or sell em to some one who needs to slow down. Some good ones are Vortecs.( can't use that manifold) Corvette L-98 alumium(ported) Edelbrock Performer RPM's (even better when ported)
World Products Torquer S/R's (again better when ported.)
W""""""P"""""s Sportsmans ( A"""""""""""""""""""""""""d)

69/74 Hi erformance camel back heads 041,040,186 ,492,034
any of the old 64 cc hi perf heads with accessory bolt holes
All need porting and 2.02x1.60 valves.
If your budget is real tight see my posts about home ported 305 heads on a budget 350

The pistons: Should be flat top to get 10:1 compression with 64cc heads.
The factory cast non performace dished piston will crack anyways. Hypereutectic or forged are better.
Federal mogul H345 hp are good and cheap
Your compression ratio is about 8.5:1 or LESS,,,,now.

rear gears: go with 3.73 or 4.10

Torque converter: this cam needs a 2600 to 3000 converter

Do any and all of this before you waste your money on 1.6 rockers. You have enough valve lift to go 12's easy.
Did I mention the exhaust system?

 

When ya get all this sorted out you'll want to shift the car at about 5800/6000 rpm. If you want the trans to auto/shift
at WOT while in drive at this rpm, you can buy a governor calibration kit from B&M to raise the auto shift points.
Check your kickdown cable to see if it is pulling properly at WOT
(carb linkage and brackets.)

 

what do you think the best timing would be? what should i set it at on the balancer, what is that base timing or intial timing, i dont know the difference. well anyways what should it read on the balancer?

 

Forget the timing mark. On a non-stock motor, it's useless; and about 90% of all balancers more than 10 years old are inaccurate anyway. Set the timing to where the car runs the best. Tweak until it gets worse when you tweak it either way. Usually it's best when it's as far advanced as possible without pinging. So advance it until it pings under worst-case conditions (fully hot, 3rd gear, up a hill, crap gas) then back it off until it quits.

Same for the carb. Get a jet kit and a spring kit and a pump cam kit, and tune it to match your car and preferences. There's no magic "perfect" one-size-fits-all setting. You've got the cheapest POS carb Holley makes, so getting it really preemo will be near impossible, but there's a fair amount of room for experimentation.

Your combo is guaranteed to be a disappointment; you've got no compression (8½:1), grocery cart gears, huge cam, huge intake, exhaust?, stock converter, etc.... lots of mismatch problems guaranteed to make the car underperform. No amount of setting the timing to some number on a mark is going to make that combo run right. Like the other post said, attack the car's weak points (not just the engine's), you'll get better results than just unbolting and re-bolting stuff that's easy to get to and looks sexy while leaving the real issues untouched.

All you need to do to the trans to get it better is to first get a red stripe modulator. Not a pink stripe, not a green stripe, and above all not the big black can type. RED STRIPE only. Look up the one for something like a 70 Monte Carlo 454 and see if that's the red stripe kind. If not, look up every listing in ATP for every kind of car with a Powerglide, T350, or T400; you'll come up with 4 possible numbers, max; one will be the green stripe, one the pink stripe, one the red stripe, and one the big black can. Then after you install it, adjust it until it shifts like you want; there's a little screw inside the hose fitting, turning it in raises the shift points. A half turn is a typical increment of adjustment.

Don't waste your money on that MSD ignition stuff unless your stock parts are broken. It isn't your problem, and that $300 would be better spent elsewhere. If you're still running your original distributor, you do need to get rid of that however; that would be money well spent.