Compression and pump gas
 

Hey guys,
Made a post in the Scarab section but thought this area would be good for a technical question.I'll be picking up my new scarab 22 in a couple days.My question is this 502Ci has 9:6.1 compression.The engine has a procharger running 6lbs of boost.My mathmatical computation put the compression at 13:5.1 at WOT.We only have 91 octane pump gas here in Colorado.The guy I'm buying the boat from is in Missouri which is about 1800 feet in elevation and Denver is 5280.The owner says he does add octane booster to the fuel.Do you feel I will have any problems running 91 octane?

Re: Compression and pump gas
 

Ill give you a bump to the top. That should be a no brainer question for some of the guys on here.

Re: Compression and pump gas
 

IMO, You will need higher octane than 91 for sure.

9.6 to 1 by it self with iron heads would need 91 octane. I'm guessing you would need more like 100 octane if you want it to live.

Re: Compression and pump gas
 

Thanks for the input....
I finally after many attempts got to talk with the procharger tech support.What a filppin' joke trying to get thru to them.Anyhow,I beleive I spoke with a fairly compentent person and he explained that at our elevation the compression will drop a solid point and a half.So if the theory holds correct,the static compression would be 12:1.1 which would be perfect for this aluminum headed motor.I have also confirmed this with AZspeed@marine.
I'm going to get the boat tommorow and cant wait to drive it.

Re: Compression and pump gas
 

I dont know much about superchargers. But, I think you should have one of these.

http://www.livorsi.com/catalog/water...NE_KNOCKMETER_