so the engine is in the car and 90% together, other than some issues i am taking care of today me and my buddy discussed since the engine is low Compression around 7.5-1 that we could advance the timing for more power while i come up with the money to turbo the car. What is a safe amount of timing to put into such a low compression engine?

Hook up a vacuum gauge to a vacuum port on the intake. Start it up and move your advance forward until you get pinging and then back it out until it doesn't.

In short, the optimum is usually around maximum vacuum at idle.

Arn

By the way, at 7.5 to 1 it is likely to be pretty lazy.

[This message has been edited by Arns85GT (edited 03-28-2013).]

With such low compression, I don't think knock / ping should be an issue. However, you will reach a point where more spark advance won't yield any more power. Either that, or driveability will start to suffer. Or maybe a little of both. You'll just have to experiment with it.

I would suggest starting at the stock spark advance (10° BTDC), and advance it 2 degrees at a time. After each bump, take the car for a spin to see how it behaves. When you reach the point of diminished returns, back the timing off a degree or two. And you should be good.

Edit to add: the method Arn outlined above should be good for setting a baseline. I'd still want to do some testing and tweaking, though.

[This message has been edited by Blacktree (edited 03-28-2013).]

Don't get carried away with it, maybe two or three degrees advance above stock and leave it, as there is still an optimum range for the ignition and combustion process to occur regardless of the compression ratio. To drive the point home further, you can apply the same theory to the stock compression ratio of the 2.8 which is tuned for 87 octane, fill it with premium fuel and bump the advance up and expect to get a good bit more performance out of it, however it doesn't work out that way. You may speed the process along to worn out rod bearings as a consequence if you're not careful.