mittens

What do any of you think about a boat that at 50-60 hours the guy put a whipple charger on it, had it tuned,a nd has run it about 150 hours with it charged. How long will it last??

motor is a 454 MPI, NONE MAG
5lbs of boost.

my parents oly sea ray had a merc 454 with over 800 hours on it an it ran fine. what about with power adder?

wannabe

Do a compression check/leakdown. 5 lbs boost is not that much. Check plugs for detonation also. Depending on what year 454 sometimes the Magnum and non-Magnum had very little in components difference.

Wannabe

98itrwhite

someone please feel free to correct me if i am wrong, but i thought the non mag 454's were cast internals which=be carefull on what you do to them. i have heard mixed reviews on modding these engines but from my personal experince they dont like being pushed to the limit.

mittens

its a 99.

bcfountain

i think the weak link in the 454 is the cast crank,3/8 rods,small valved,small runner heads.i re-did a 454 with a 250 blower,6pounds of boost.i used the cast crank,put studs in the 2bolt main,and used eagle sir rods,3/8.the motor runs well for what it is ,and has about 160hrs on it.i have ran about 5-8 miles at wot under boost,with no problems.i think if you drive smart,use good fuel,and ckeck the other things mentioned,you will be good.

Griff

The 454mpi is WEAK and a poor candidate for an SC. I would steer clear of it.

mittens

I understand that its does not have the forged internals like a mag, but its only at 5lbs of boost. if tuned correctly do you think it will be a problem?

bobl

Being a '99, it is the Vortec engine. It has the fast burn heads. These are not good candidates for supercharging because they will detonate very easily. You don't hear of many success stories supercharging these engines.

mittens

Yes he said he changed the heads when he put the whipple on, becasue he knew they can cause early detination.