How Much Boost????
02-21-2022, 10:34 AM
#51
Registered
Great thread
02-21-2022, 01:37 PM
#52
Geronimo36
Gold Member
Damn, this is an old thread!!!
In 2015 I built a completely new set of engines for the boat. They have over 275hr on them and I freshened the top ends last year.
8.3:1 compression
AFR 357CNC
Custom Hyd. Roller Cam w/ Johnson Racing lifters
8:71, 3% overdriven
6psi boost.
964HP and 924t lbs.
In 2015 I built a completely new set of engines for the boat. They have over 275hr on them and I freshened the top ends last year.
8.3:1 compression
AFR 357CNC
Custom Hyd. Roller Cam w/ Johnson Racing lifters
8:71, 3% overdriven
6psi boost.
964HP and 924t lbs.
Static compression 8.1:1
Boost pressure 5 psi
Displacement 580"
Heads Merlin 345 w/ 126 CC chambers.
Cam: Lunati Hyd. Blower Cam (.571 - .580) the rest I'm not sure
8-71 Hampton Blower underdriven 5%
766 hp and 753 lbs. torque at 4500.
I went with a conservative setup for longevity but I could always pump up the boost if I want more juice.
Boost pressure 5 psi
Displacement 580"
Heads Merlin 345 w/ 126 CC chambers.
Cam: Lunati Hyd. Blower Cam (.571 - .580) the rest I'm not sure
8-71 Hampton Blower underdriven 5%
766 hp and 753 lbs. torque at 4500.
I went with a conservative setup for longevity but I could always pump up the boost if I want more juice.
The following users liked this post:
I'CE (03-12-2022)
02-21-2022, 02:06 PM
#53
Registered
Damn, this is an old thread!!!
In 2015 I built a completely new set of engines for the boat. They have over 275hr on them and I freshened the top ends last year.
8.3:1 compression
AFR 357CNC
Custom Hyd. Roller Cam w/ Johnson Racing lifters
8:71, 3% overdriven
6psi boost.
964HP and 924t lbs.
In 2015 I built a completely new set of engines for the boat. They have over 275hr on them and I freshened the top ends last year.
8.3:1 compression
AFR 357CNC
Custom Hyd. Roller Cam w/ Johnson Racing lifters
8:71, 3% overdriven
6psi boost.
964HP and 924t lbs.
The following 2 users liked this post by Panther:
PROP STAR (03-01-2022), Unlimited jd (02-28-2022)
03-10-2022, 07:57 AM
#55
Registered
Thread Starter
I dont remember half the stuff in this thread 
Ironically i just stumbled across this video last week Crazy
I had hair and no brains back then!
sry i used my phone on the plasma on vhs c
i think its the combo above that was in my hustler with arnesons.
Ironically i just stumbled across this video last week Crazy
I had hair and no brains back then!
sry i used my phone on the plasma on vhs c
i think its the combo above that was in my hustler with arnesons.
03-10-2022, 07:59 AM
#56
Registered
Thread Starter
i think the rod flew out the side... thats why it ended so quick
03-10-2022, 01:14 PM
#57
Registered
Bassett Headers? Sweet!
How much boost?
How much boost?
03-10-2022, 01:18 PM
#58
Registered
Anybody know the story. It did end rather abruptly.
Went back and listened again. Even with my deaf azz ears it sure sounds like something let lose. Sounded like top end though.
Last edited by getrdunn; 03-10-2022 at 01:21 PM.
03-10-2022, 02:12 PM
#59
Registered
525SC was a 7.5 compression 5.5psi engine running very rich I thought ??
My 600SC ran like a champ for 300hrs, I never saw over 5psi so maybe Mercury knows something .
My 600SC ran like a champ for 300hrs, I never saw over 5psi so maybe Mercury knows something .
03-10-2022, 02:48 PM
#60
Registered
We had the early on 1992 525 sc’s. Just a little over 5 pds boost with no innercoolers. They were pig rich but ran the dog chit out of them without any failures. I should’ve spent some time getting jetting right but didn’t then.
