Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Boating Discussion (https://www.offshoreonly.com/forums/general-boating-discussion-51/)
-   -   250 Supercharge on a 9.5 compression 454 (https://www.offshoreonly.com/forums/general-boating-discussion/123436-250-supercharge-9-5-compression-454-a.html)

alcor 02-26-2006 03:42 AM

250 Supercharge on a 9.5 compression 454
 
I bet this one will get a lot of varying opinions.

Just ordered a couple of 250 supercharges :D to install on my twin 454's that have about 50 hours on them. Here's the question. Can you get away with running about 4 pounds of boost with the 250 blowers with a 9.5 compression motor?

Not looking to run all out all the time, just want to be able to create a bit more power when I want it. Currently these 454's are at about 500 hp and hoping to get about 600 to 625 with the upgrade. With the 425 TRS outdrives, I simply don't want to run anymore than that for fear of hurting the drives.

So what are some of your thoughts? Can I get away with this without having to pull the engines and change pistons to lower the compression or is burning a piston inevitable?

f311fr1 02-26-2006 09:09 AM

Re: 250 Supercharge on a 9.5 compression 454
 
Talk to Dean Nickerson. I ran this combo for several years in a 311 Formula with Bravo,s. If your pistons are stock your CR is more like 9:1. You could always use thicker head gaskets to shave a 1/4 point or so off. Joe Murray

alcor 02-27-2006 05:54 AM

Re: 250 Supercharge on a 9.5 compression 454
 
Thanks Joe. You know I presumed it was 9:5. The fact is these engines have TRW piston and they are .30 over stock. I couldn't find a part number but they have a slight dome on them. 9:1 would make me feel a little better. How much boost were you running on your set-up?

How would I reach Dean Nickerson. Appreciate the response.


All times are GMT -5. The time now is 06:09 AM.


Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.