Supercharger for my Apache

[diceman50]

Thanks Dan,

I don't know what the compression ratio is going to be. I have read online that putting the 235 "848" head on a 261 will raise the ratio approx. 1/2 point. If so that will put it about 8.5 to 1. Whatever it is it should be well within the acceptable range for forced induction.

The McCullough supercharger has its own oil reservoir and is air cooled. Sometimes an oil cooler is added for max horsepower or racing applications. Shouldn't be an issue for me.

As for an intercooler I will not be using one. There are several things involved in deciding whether one is needed or not including C/R, engine size and type, cylinder head design, etc., but generally speaking an intercooler is not considered necessary if boost is limited to 9 or 10 psi. Well below the capabilities of a McCullough. There might be a slight performance advantage by using one, but that is not what this project is about. I want this to be something that you might have seen in the 50's or 60's. Notwithstanding the EFI.

In anticipation of adding the supercharger, Greg installed a new operating system on the current engine a while back. The new system will support a 2 bar MAP sensor which we installed at the same time. This allowed us to make sure it is going to work in non boost situations as well as the previous system did. So far so good. When the new 261 is installed we will run it without the supercharger until we get the fuel injection dialed in for the bigger displacement and more aggressive cam. Then we will add the blower and start over again. The object is to not add too many variables at once.

I hope I answered all your questions. If not don't hesitate to ask again.