Ignition timing
 

I replaced the stock 330 over the winter here are my specs.
468ci
9:1
merlin oval heads
Hyd Roller cam .600 lift 114 [email protected]
performer rpm
C&S arosal carb 850 cfm
gill ex
stock 330 ignition
It is in a formula 223 with a 21 4 blade prop I am getting 72 on gps and the tach says 5300 it sounds like alot more so I am replacing it.The boat seams a touch doggy getting up on plane when the air is bad and its loaded heavy I set my timing at 33 degrees@ 3000 it seams like the power comes on big time right around 3500 I am wondering if my timing is to low I run 93 at all times any suggestions?

If you have a TB IV with a stock v8-24 module, full timing advance does not come in until around 3700rpms. If you are 33* at 3000rpm, you could easily be at 37-38* at 3700rpms---which is too much.

I ran my 468 with similiar set up to yours but I had MSD ignition at 35 total. We dyno'd the motor and there were no issues with spark knock at 35 degrees using 89 octane.

34-36 timing all in. Check it at 4000 rpm so there is no guessing if your full advanced or not. Don't worry where base timing ends up but it should be 14-16 if your using a v8-hp module . If still sluggish or stumbles around 1700-2200 rpm then use a v6-14 box still set at 34-36 all in. Base timing will then be 22-24

I'm sorry I just read and your using a v8-24 module? Not too good for what you built . At 34 all in timing you only have 10 base. The advance curve of that module is very long and slow so your bottom end performance will suffer a lot. Poor idle, poor response until 2600 -3000 rpm

i am using the v8 module and it does stumble if i dont get on it easy some times

There are about 8 different V8 modules. The timing curves are different on all of them. Max timing advance comes in at different rpms depending on which module you have. They all have between 20 and 24* of total advance, but the curves are different. If you want to set the timing at max advance, you need to know which module you have.

Setting it at 33* at 3000rpms does no good if it does not fully advance until 4500rpms. You could be risking some serious issues caused by detonation if do it wrong.

How do I know what one I have and what one would work the best for my application?

It should say on the module.

Module will be stamped V8-24, V8-22, V8-20, V8 HP,.......
The number represents total advance . The V8-hp is 20 degrees of advance but has a sharper curve and is all in at a lower rpm than the V8-20.
It's an old trick to use the V6-14 module on a Big Block . On an 8 cyl engine the v6-14 module gives 10 advance. If you set full advance timing at 34 then your base timing will be 24. That gives the engine much better idle quality and also more responsive in the idle to 2500rpm range. Engines with larger cams are much better with more initial timing. I can tell you why but too long to type.
So I short the best module for you is V6. Then V8HP, third V8-20 , V8-22, V8-24.