I've just finnished putting together my 1.6 TD bottom end and will be running the 1.9 AAZ cylinder head. The highest piston pertrusion that I measured is .60mm. Now in the Bently, the one notch I think starts with .63-.68mm? I don't have the book infront of me right now but, should I be using the one notch or maybe a two notch to help lower the CR. Or will it be lower than normal because of the 1.9 head anyway, and just use the one notch.
Just would like some insight because this is going to be a frank-n-motor, and don't know what will be the best set up?
Thanks, Josh
From past reading, if you go with the 2 or 3 hole you may run into cold weather starting problems. If it is going to be a warm weather ride you could go 2-3 hole. Really the only reason to run the thicker HG (and mess with the squish) is to allow you to run higher boost. I think the 1 hole will give you around 19-20:1 cr. You should be able to raise boost a good bit at that level. All depends on if have oversize pistons, coated pistons, etc etc. but around there. All depends on what you want to do. I went with a 1 hole on my franken.
The pistons are .50mm over and are aftermarket no namers. No coatings on them and using Maley rings. The main use will be 1/4 mile at a time. So cold weather starts will not be an issue as the late night drags will be ending here in Portland in Nov. but will be installed in my pickup to set the rings and just to dia it in. The max boost levels will be topped out at 30psi but will be set way lower for the break in period for the rings. I think I read some where in here that using a 1.9 head on a 1.6, the CR would be lower because of the pre cup size. If so sould I use the two notch to lower it more sence using 30psi or just use the one notch.
Josh
Yeah, if it's a drag car you can go all out. I have an extra 3-hole AAZ gasket I did not use if you are interested.