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View Full Version : 22RE timing at altitude?


bskey
02-10-2008, 10:45 AM
I'm finally getting around to setting the timing on my 22RE. Factory recommends 5 degrees, but I have heard that I should advance it due to altitude. Also, at some point I should use higher octane. Any advice on this would be appreciated!

Thanks~

Brett

DaveInDenver
02-10-2008, 02:19 PM
If you run 91 octane, then you will be forced to advance the timing beyond 5 degrees. At 5 degrees, I have noticeably less power without pushing the advance to 8 degrees and then it's only about the same power as 87 at 5 degrees. The 22R-E doesn't need 91 and can't really take advantage of it. Stock and free of carbon build up, they are 9.2:1 compression. I would stick to 85 and 87 (I run 87) and 5 degrees.

Red_Chili
02-10-2008, 05:04 PM
Agreed. The motor does not benefit much from advance. However, if you want to try, just make sure you don't ping. My last motor needed 87 to not rattle, and would accept no advance. I suspect the Jasper motor had a bit of a milled head from stock.

bskey
02-10-2008, 07:24 PM
Would you define "pinging" for me? I am not sure what to look for there. I just got a timing light, and the engine was set at about 7-8, and I moved it to 5, and I am noticing a bit less power. Also, at 7-8 it was running rich. I prefer safer/less power to damaging/more power. But I'd love to find a happy medium.

Thanks again for your help!

subzali
02-10-2008, 08:04 PM
You'll notice pinging big-time if you are in 2nd and slow down realy slow, like going through a dip, and then hit the gas on the other side without shifting into 1st. If you don't hear a REAL bad noise, slow down more next time and try again :hill: Of course it's harder to pick up at highway speeds, but some vehicles will do it at highway speeds. I run 87 in mine and I think I found its happy place to be around 6 degrees, just barely above 5 really.

DaveInDenver
02-10-2008, 10:20 PM
On mine it sounds like the little gerbils in the engine are throwing marbles against the header primary pipes. I know you have a header, which really helps you hear everything inside the engine. Seriously, imagine dropping #000 buckshot or maybe a handful of pennies on your header and that's the closest sound I can think of.

bskey
02-11-2008, 08:16 AM
Wow.. that'll be obvious then. I guess I'm happy I haven't heard that sound yet. So advance it until I hear that, then back off a bit and give her a try? I guess this will just be trial and error. Can I do this on a cold engine, or should I wait until it warms up, or is that not a factor?

Red_Chili
02-11-2008, 08:22 AM
It is very much a factor. Wait till it is thoroughly warm. Oh, and winter fuel WILL make a difference, so plan on changing it come spring.

DaveInDenver
02-11-2008, 08:35 AM
Can I do this on a cold engine, or should I wait until it warms up, or is that not a factor?
Totally a factor. Pinging is the fuel igniting early or burning too fast. It can be because the ignition is timed to fire the spark plug early, too low of octane, a hot spot in the combustion chamber. It happens for various reasons. But a stone cold engine won't really ping (in fact you get bad fuel vaporization cold and so a cold start is done en mass by dumping tons of fuel into the engine and hoping at least a little burns), it's normal operating conditions that you're after. If you're trying to do it by ear, then you'd have to get out and drive on the highway for a while to get the engine good and uniformly warmed up. Then I suppose you could mess with it. I used to do a tune-up in November and another in April back when they'd start and stop adding oxygenates (the ethanol in our gas). Now it seems most stations just have 10% ethanol all year, which sucks, oh well. Air temperature has an affect on the pinging in my engine, so in the winter I can usually run a little more advance than summer. Not a whole lot, like a degree. But the ECU takes care of this for you, presumably. According to the book the ECU will advance until it detects knock (the 22R-E has a knock sensor, just above the oil filter on the side of the block). How good that system is, well hard to say. Valve tick, header noise, etc confuses a pretty dumb system and so it's probably not nearly as effective as more modern anti-knock controls. But it tries anyway.

Red_Chili
02-11-2008, 09:00 AM
... But the ECU takes care of this for you, presumably. ...How good that system is, well hard to say.
Not good at all.

DaveInDenver
02-11-2008, 09:28 AM
Not good at all.
That's my assessment, I'll be darned if it does much. But it's there none-the-less.

Red_Chili
02-11-2008, 09:59 AM
It's there to throw a code if it dies. :hill:

bskey
02-11-2008, 12:11 PM
Wow... great responces. Thanks guys! Do I need to take her on the hwy to get the engine warmed up? My drive home is 15 min of stop & go; could I just do it after that. The engine temp is up by then.

...Im not sure I would trust the knock sensor too much. My fuel injection is really loud too, and it always reads "normal" codes.

Red_Chili
02-11-2008, 12:14 PM
Sure, that should be enough. You can always adjust it later if it proves to be a bit much.