408w timing

[brainsboy]

Where do you guys set the timing on your 408w's? Mine seems to like around 10-12, just wondering if this was normal

[Tommy]

brainsboy -
Your question leaves a lot of room for an answer. I assume you are speaking of initial timing at idle. The answer depends on the total mechanical advance programmed into your distributor and whether or not you have vacuum advance. It also depends on your compression ratio, fuel octane, the prevailing air temperature and some other things. ... Many folks without a vacuum advance set the intial timing such that it plus the mechanical advance equals the total they seek. On my 410 Windsor with 9.8 C.R., I set the total advance when using 93 octane gas at about 32 degrees.

[Mr.Fixit]

I used to set that at 10 initial, plus another 20-22 mechanical, all in by 2500 rpm, no vacuum advance.

but there are too many variables to give a correct for your motor answer

[brainsboy]

Well I just got this motor running and havent checked total advance yet. Here is my setup though.

408ci
Aluminum heads 2.08/1.60
10.68:1 compression
HydRoller - 224/238 .545/.568 3400-6800
Victor Jr w/ 750cfm carb
exhaust 1-3/4 shortys to 3"pipe
3800stall
3.89gears 28"tires

[Keithc8]

With the Victor Jr heads you will find that the engine will run best at about 32 to 34 degrees total timing. This may fall back to 6 to 12 degrees initial. This will depend on how your mechanical advance is set up inside the distributor as the other guys said. You can also change the springs so that your timing comes in at 2500 to 3500rpms, the stock setting on the distributor from MSD will not total out till about 5000rpms. Good luck Keith

[MidOHasp]

Whose carb?

Demon carbs like a lot of initial timing (14 deg) which means recurving the distributor could help. Or if you have your A/F mixtures set right, you can just run a wee-bit more total timing and make it happy.

I run about 14 degrees initial timing, 33-34 total. Switching from CAM-2 to 92 octane made all the difference and eliminated a stumble I had.

Considering retarding the timing back to 30 total, 10 initial, and seeing how it runs.

[392cobra]

http://www.cobralads.com/gear/msd2.gif

You didn't say if you have a MSD dist. or not but if you do the link above will help in recurving it.

The MSD comes from the factory with the blue bushing and the heavy springs.

My 418W is set up with the blue bushing and 2 blue springs for a total of 36 degrees for street driving. 15 degrees initial advance,calculated. I set it for total and not worry about what it might be at idle.

[brainsboy]

OK guys here is what I have now. I set the timing at an idle and put it at 10. I reved up the motor and the total timing went to 42-43 hard to say as my balancer only reads to 40. In order to get to 34 I would have to set the timing at less then 0, so I know I need to change the springs. My question is if i dont change the springs and run the motor at 42-43 will this cause any problems?

[trularin]

I do not use the initial as a setting, but the final. With my CAM I must be between 32 and 38 degrees at 3000 RPM.

I have a IR mechanical distributor with NO vac advance. So, that works out to be 18 degrees BTDC warm.

[trularin]

J.P., tried that 10 and 30 and got intermittent backfires. 32 is as low as I can go, or change the gas.

[Tommy]

brainsboy -
I'm no expert, but I have had some experience that you may find illuminating. I damaged two pistons on an earlier 351W engine due to detonation. Detonation can be caused by premature firing of the spark plug (i.e., the timing was too far advanced for the combination of compression, fuel octane, air temperature, etc.). Keithc8 (an engine expert) suggested a total advance of 32-34 degrees. In my non-expert opinion, you certainly can do greivous damage to your engine running 42-43 degrees of advance. I'd change the springs right away to bring the total advance down some.

[392cobra]

What brand of dist. do you have ???

Springs control to rate of advance.
Cent. advance bushing controls the amount of advance.

Kind of sounds like your cent. advance bushing is missing.

[brainsboy]

I have a regular Mallory distributor. Are these distributors supposed to have that wide of an advance from the factory? 10 to 43 seems like alot.

[392cobra]

It looks like it is set to the max the advance system allows,32*.

http://www.centuryperformance.com/ma..._AdvCrvKit.pdf

This link from Mallory should allow you to get your Cent. advance sorted out.

[392cobra]

Some more info for you.

--------------------------------------------------------------------------------

The Distributor Series Designation:

Your distributor SERIES number is the first two digits of the numeric part number (automotive applications). On Marine applications this can be a bit tricky. On marine applications you will need to know what style distributor you have (breaker points, M.B.I., or Unilite®). With that information you must look at the drawing and decide what advance style you have, and what type of cap you have (CAUTION: You cannot swap a flat cap for a stack cap or vice-verse, the distributors are inherently different). Mallory has changed advance styles over the years and the current style is a "YH" advance for both automotive and marine applications which will be stamped on a tag on your distributor. Even though your Marine distributor says "YL*****" as the part number, it may or not be a "YL" style advance system. It is your responsibility to look at the assembly drawing and verify the advance style.

Mallory's Distributor Advance Upgrade Service:

Mallory offers a unique service that "for a fee" and if you have a distributor that meets the requirements (meaning it is not a prehistoric version), that you can upgrade your YL, YT, or YS series advance style to the newer YH style advance. This can be done to automotive and marine distributors. You must send your distributor to Century Performance Center for this upgrade. We hand deliver these items to Mallory usually the same day we receive it. Typical turnaround time is 3-5 days. For more information please contact us at: csm@centuryperformance.com

Mallory Repair Service:

On certain products (besides warranted items), Mallory offers a repair service of these items. Whether it is a distributor you want to have upgraded to electronic trigger, or a fuel pump that needs to be rebuilt, we at Century Performance Center can take care of this service for you. You must send your items to Century Performance Center and depending on the item, the turnaround time is *typically* 5 business days or less. All work is performed by Mallory techs. We hand deliver these items to Mallory on your behalf usually the day we receive it. For more information please contact us at: csm@centuryperformance.com

http://www.centuryperformance.com/mallory/assm.asp

[brainsboy]

Thanks for all the info

[MidOHasp]

Let us know how it all works out, OK? That is the price you pay for info.

We gotsta know if it works!