Highest torque in a 1.8L engine?
 

Like the title says; silly question: where in the 1.8L engine's RPM band does one see the highest torque?

Thanks

I don't know off hand. IIRC it's 4500 rpm, might be 4800 though. It also has to do with your spark tuning Rafa. If your spark map is garbage your torque might peak earlier then that and then drop drastically to redline.

Stock 2001 on a dynojet. 4400-4800 is the max but it's pretty flat. and you know you love the 100 ft lbs from 2200 rpm.

http://www.y8spec.com/dyno/miatadyno20040709.gif

I'm trying to retard a little timing in the peak torque band to avoid issues.

BTW, thanks for the info guys!

Another dumb question....

This is a quote from the AEM EFI Basics manual:

" Spark plug selection affects engine performance. On forced induction engines, it is critical that the proper heat range and gap is used. Heat range refers to the ability of the spark plug to conduct heat away from the electrode to the engine. A plug that has high thermal conductivity has a short insulator that comes in contact with a large portion of the metallic plug shell. This large area allows the combustion heat to be carried through the plug shell to the cooling jacket of the cylinder head. In the case of a hot plug, the insulator is recessed deeply into the plug shell with minimal contact to the shell. The plug has low thermal conductivity due to the lack of contact with the shell. The nose of the insulator should operate at between 400 – 850 degrees C. Temperatures above 400 degrees C are desirable because at higher temperatures deposits from carbon, lead or soot are burnt off. Temperatures of 850 degrees C and over should not be exceeded because this is typically the point where detonation or auto ignition can occur. Lower heat range plugs have a higher resistance to auto ignition while higher heat range plugs have less tendency to foul."

So, my question is: everyone talks about EGTs; is there any simple way to know what are the temps at the spark plugs?

Thanks

not exactly but yes...

you can take them out and read them. generally though, you want to run the coldest plugs you can without them fouling. or the hottest plugs without risking detonation. or half way between?

http://www.atlanticjetsports.com/Tec...olorchart1.jpg

I run the stock spec plugs at a big ass gap, and they look just like the top left picture in Y@'s chart.

I believe that you should run the hottest plug that doesn't detonate. However, if you're a crappy tuner, paranoid, or if you're on track for long periods, you should go a little colder to err on the side of caution.

An overly cold plug will only foul up, give less than possible economy and power. An overly hot plug could cause you to loose your motor.

So there's no sensor available that will allow anyone to get feedback on the plugs' temp? I'm thinking that if I could keep an eye on my plugs' temp at all times I could prevent knock much easier than by reading EGT; I'm I wrong?

And about the gap; I'm a little confused Ben because the AEM manual states that in modern fuel injected, turbo engines one should keep the gap around 22 and you guys all run a much wider gap. :vash:

the guys who run COPS can run a bunch of plug gap because they are men, and we are their bitches.

Do you mean you're my bitch now? :giggle: