User Tag List
Thanks: 0
Likes: 0
Results 1 to 3 of 3
Thread: Heads Johnson 115.
-
06-18-2019, 11:55 AM #1New Member
- Join Date
- Jun 2019
- Location
- Norway
- Posts
- 3
- Thanks (Given)
- 0
- Thanks (Received)
- 0
- Likes (Given)
- 0
- Likes (Received)
- 0
- Mentioned
- 0 Post(s)
- Tagged
- 0 Thread(s)
Heads Johnson 115.
Hello, i am new here and hope someone can answer my question...i have a 1998 115 Johnson Oceanrunner, this engine is fully rebuild.
We have 95octan pumpgas here and my question is how mutch i can cut the heads, i want a bit more compression/torque.
I have build my own raceengines for 20years but never did porting or other tunup on outboard engines so if someone can answer i hope i not need to calculate the chamber volum/compression ratio.
Sorry about my poor english
-
06-18-2019, 12:49 PM #2Banned
- Join Date
- Jan 2015
- Location
- Wisconsin
- Posts
- 2,331
- Thanks (Given)
- 458
- Thanks (Received)
- 343
- Likes (Given)
- 6429
- Likes (Received)
- 5147
- Mentioned
- 4 Post(s)
- Tagged
- 0 Thread(s)
If you do not know your current compression psi, you are just guessing.
If you do not get a response from anyone here, what I would do is test for compression, then remove heads and bring them to machinist to cc them. Just my .02
-
06-21-2019, 07:41 AM #3Scream And Fly VIP
- Join Date
- May 2001
- Location
- Hickory NC
- Posts
- 5,583
- Thanks (Given)
- 18
- Thanks (Received)
- 250
- Likes (Given)
- 204
- Likes (Received)
- 464
- Mentioned
- 4 Post(s)
- Tagged
- 1 Thread(s)
Due to the dome in the piston you cant just cut them you need to recut the squish as well. Also depends on what it is pushing.
Similar Threads
-
2.7 heads, Stock Johnson V6
By Tightrig 12 in forum Technical DiscussionReplies: 17Last Post: 12-02-2017, 03:57 PM -
Wtb johnson v4 140 heads NY
By 95glas in forum Outboard EnginesReplies: 1Last Post: 03-20-2016, 08:46 AM -
johnson 150 and 175 heads
By bassone75 in forum Technical DiscussionReplies: 1Last Post: 10-13-2014, 04:26 AM -
1991 Johnson 120 Heads
By 59Ford in forum Technical DiscussionReplies: 10Last Post: 04-01-2014, 08:50 AM