spark table advance with c16 fuel

[ponix88]

can someone tell how much can advance the timing of spark table with c16 fuel race

[edcmat-l1]

can someone tell how much can advance the timing of spark table with c16 fuel race

No. Not without a lot more info on the setup. The fuel alone does not dictate how much spark advance you can run. I've tuned high compression LS motors running C16 that could only take 25 or 26 degrees of timing. No more than a 11:1 street motor running 93 octane. Actually less than a lot of street motors.

[decipha]

x2 your best bet is to yank the plugs and see what the engine likes

[ponix88]

ok the motor is camaro 99 ls1 A4 with some Bolt-Ons not big deal
i have another question about the spark plugs in tuning i use ngk sparks plugs so what is the best in tuning iridium or platinum

[gn2beatu]

You cant go by plugs or octain when tuning timing. Every car is differant. Advance it no more than 28-29 degrees in the upper RPM, OR UNTIL you start getting retard. Whichever comes first. Most LS engines like at least 25 degrees on 93, Im personaly at 28 with 93 octain. There is very little to no gain after 29 degrees timing.

In the midrange (peak torque) most will run 19-20 degrees on 93 octain in the mid range 3500-4800 ish. Then taper to the 28 (or whatever you can run) to the upper RPM. VERY IMPORTANT, google MET. It is the mean effective timing (might have the first word off LOL, waiting on the word police) What it means is if you go even one degree over your best timing, its worse than running 10 degrees too little timing. You will see what your motor likes also by comparing accelearation by frame count. You will see your time vs acceleration slow down as you get to your best timing.

Hope that helps some.

[ponix88]

gn2beatu
thank so much for your advice

[edcmat-l1]

Running C16 in a lower comression engine won't do anything. It won't make any more power than running 03 octane. The octane rating of a fuel is it's ability to keep from detonating, or pre-igniting, nothing else. It's not a rating of it's ability to make power, or HOW MUCH power it can make.

C16 is for very high compression engines, or engines with very high cylinder pressures.

Timing is a totally different subject, and it in itself does not make power either. The amount of timing an engine wants depends on many factors, octane being only a small part. The basic idea is, you want peak cylinder pressure at 15 deg ATDC. The amount of "lead" this requires depends primarily on the efficiency of the combustion chamber. The efficiency of the chamber is based on shape of the chamber, shape and design of the piston crown, quench. etc. LS motors have very efficient chambers, hence the reason they don't need much timing. Or want much for that matter.

Bottom line, running C16 in a lower compression engine is a huge waste of money.

[Chris@HPTuners]

agree 100%. most non-oxygenated higher octane fuels (like c16) actually burn slower because they are less volatile than pump gas (thats why they need a little more timing). They make more power because they let you run higher compression (or more boost) without detonation. Higher compression or boost means more cylinder pressure and more torque.

like ed says on a stock motor it's a waste, you'll probably make less power.

[Chris@HPTuners]

the other thing you will want to know is that C16 fuel contains lead, ie. it will destroy your cats, O2 sensors etc.

[edcmat-l1]

the other thing you will want to know is that C16 fuel contains lead, ie. it will destroy your cats, O2 sensors etc.

Good point. Yeah, they will destroy the O2s in no time.

[ponix88]

thank so much i don't know about the o2 so thanks about the info

[gn2beatu]

If you need a little more than 93 has to offer, but dont want the lead. You can make homebrew high octain. You can mix up to a 20% mix of tollulene, xylene or xylol with 80% gas. xyelene has one more point of octain than tollulene. Some run up to 30%, but it is a very dry product. It dries out seals, etc. So its good to put 1/4 cup of marvel mystery oil or WD40 in a 10 gallon mixture. I wouldnt run it all the time, maybe just at track days. I was able to run 8 degrees more timing on a turbo motor, and 6lbs more lbs of boost. Gained around a 1/2 second in the Grand National with that mixture.

x2 to what the others said about it not being needed on a stock NA motor. And it will only take 1 tank to destroy your O2 sensors. Not sure about the cats how long it takes, but it wont take long as the lead coats the platinum.

Hope that helps some.