Timing question.

With aluminum heads you can get away with a good deal more base timing than stock - 14-18+ isn't uncommon for aluminum heads. For iron heads 12-14 is usually the limit.

Running premium fuel will let you go higher than on regular fuel.

HOWEVER... you're running nitrous and a supercharger - just the slightest ping is going to wreak havoc on your setup - your best bet is to take it to a dyno and get it professionally tuned... it's a small price to pay considering the amount of $ you have already spent!

Pull the vacuum off the distributor to keep it from advancing over the base timing and set it with a timing light at the balancer.

I've read a few things here and there saying that as you get above mid 30s total spark advance you won't really gain any power - I've never tried it myself but I have seen it several places. A dyno tune will tell you for sure and you definately want to tune your combo on a dyno.

Get a dyno tune then flog on that beast without fear!

Wes

Edit - just to make it clear again - since you have a supercharger, advancing the timing too much is going to be your enemy.

My Vortech S-trim tune for my '95 locks total advance out at 21* during WOT which is the norm comparing to other people's tunes.

The fact that it's a stroker engine doesn't make alot of difference.

Fuel grade, overall compression ratio (taking boost into account), cam design, and head/block design all play a larger roll in timing.

If the engine is cranking over slowly: If the problem is indeed the timing, then it means the timing is too far advanced during crank/idle. Generally you'll want to shoot for around 14-15* base timing. Slow engine cranking can also be a result of a high static compression ratio, poor battery or starter, as well as poor electrical connections or cables.

What are you using to control timing? MSD BTM? I'd shoot for 36* total timing at 0" of manifold vacum (atmosphere pressure). Then pull timing out based on amount of boost. That should get you close. The fine adjustments will have to be done on a dyno or at the track as no 2 engines are exactly alike.

Does it become harm to crank sometimes, after you run it ? Or on first crank when cold. Headers can sometimes heat a starter pretty good, and make it hard to start. Do you have a vacuum advance ? You want about 32-38 depending on what the motor likes. The track can tell you that one. The vacuum you can run more with. And it will take a little timing out when your WOT.

Keep it simple. Every motor and every re-build is different.

Remember, Fords like a lot of carburetor and a lot of timing.

Get under the hood and rev the motor to 4 grand. Rotate the distributor until the motor begins to "cut out" and then back off the distributor a bit. This will be the sweet point for YOUR particular engine.

HistoricMustang
www.historicmustang.com

HistoricMustang said:

Keep it simple. Every motor and every re-build is different.

Remember, Fords like a lot of carburetor and a lot of timing.

Get under the hood and rev the motor to 4 grand. Rotate the distributor until the motor begins to "cut out" and then back off the distributor a bit. This will be the sweet point for YOUR particular engine.

HistoricMustang
www.historicmustang.com

Click to expand...

I'll have to give this a try, but intuitively this sounds way wrong to me. I would think that you would end up with way too much timing if using this method. With little load on the engine, you'll have alot of manifold vacum and this would result in significantly less cylinder/gas pressure than if you had the car at WOT and no manifold vacum. I was always told that as cylinder pressures go up, timing has to go down.