How much HP reliably with Oval port Merlin Heads?
#1
Charter Member #232
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
Thread Starter
![Default](/forums/images/icons/icon1.gif)
I just got a pair of 454 motors. I dropped them off at the engine builders and he will have them apart this week I hope. What I am trying to figure out is what to do with them. They have Oval Port Merlin heads and I am wondering what is the best set up. Sould I keep them naturally aspirated, or go with blowers. I want to see mid to high 70's out of my boat (Formula 302 with a lot of lightening mods) so I will need btwn 500 and 575hp I figure so that is my goal hp wise. I know that the oval ports are better for low end grunt however can I get the HP that I am looking for with those heads?
Jon
Jon
__________________
Put your best foot forward!
Put your best foot forward!
#2
Registered
Join Date: Jan 2001
Location: Holland MI
Posts: 3,140
Likes: 0
Received 0 Likes
on
0 Posts
![Default](/forums/images/icons/icon1.gif)
The ones I have done in the past made 505 on the dyno, very mild 454 engines with Merlin oval-port heads. Call me if you'd like. home,616-738-0474 or cel,616-403-3962.
#3
Platinum Member
![](https://www.offshoreonly.com/forums/images/icons/platinum_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
Audiofn,
I built a set of 454's with the 269cc oval port merlin's for my 311 that made 530 HP and pushed the boat to 74 MPH in fresh water.
I built a set of 454's with the 269cc oval port merlin's for my 311 that made 530 HP and pushed the boat to 74 MPH in fresh water.
#5
Charter Member #655
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
The motors that Crazy is talking about are mine and SuperV's they even had flat tappet cams add a roller cam and some head work 550+......
__________________
If your boat has a sail do you ride a horse to the ramp?
If your boat has a sail do you ride a horse to the ramp?
#6
Charter Member #232
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
Thread Starter
![Default](/forums/images/icons/icon1.gif)
Do you guys think those motors are maxed out? What do you guys think about dropping compresion a little and puting a blower on there?
Jon
Jon
__________________
Put your best foot forward!
Put your best foot forward!
#7
Charter Member #655
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
![Default](/forums/images/icons/icon1.gif)
maxxed out?depends on what you mean????add a stroker crank and 40 ci you might get 30 more hp. add a blower lower the compression...600 on pump gas.
__________________
If your boat has a sail do you ride a horse to the ramp?
If your boat has a sail do you ride a horse to the ramp?
#8
Charter Member #232
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
Thread Starter
![Default](/forums/images/icons/icon1.gif)
I can get a pair of blowers from the guy building them for cheap. Will have to find oval port intakes but they are not so bad from what I understand. They are the same blowers that you have Sutphen. Yes yes your trannies I will certainly need. Now I just need to save up the money again ![Big Grin](/forums/images/smilies/biggrin.gif)
![Big Grin](/forums/images/smilies/biggrin.gif)
![Big Grin](/forums/images/smilies/biggrin.gif)
__________________
Put your best foot forward!
Put your best foot forward!
#9
Charter Member #232
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
Thread Starter
![Default](/forums/images/icons/icon1.gif)
Originally Posted by dyno
maxxed out?depends on what you mean????add a stroker crank and 40 ci you might get 30 more hp. add a blower lower the compression...600 on pump gas.
The exhaust that I plan to run is a Mercuiser/Gill set up.
Jon
__________________
Put your best foot forward!
Put your best foot forward!
#10
Charter Member #232
![](https://www.offshoreonly.com/forums/images/icons/charter_member_star.gif)
Thread Starter
![Default](/forums/images/icons/icon1.gif)
Has to be wet due to the noise issues that I am sure that you read about Biggus and the gang up on the lake. I actually prefer wet anyhow just due to the comfort level on the boat. I just want to have fun not piss people off ![Big Grin](/forums/images/smilies/biggrin.gif)
![Big Grin](/forums/images/smilies/biggrin.gif)
Jon
![Big Grin](/forums/images/smilies/biggrin.gif)
![Big Grin](/forums/images/smilies/biggrin.gif)
Jon
__________________
Put your best foot forward!
Put your best foot forward!