Go Back  Offshoreonly.com > Technical > General Q & A
Engine Gurus? >

Engine Gurus?

Notices

Engine Gurus?

Old 02-04-2009, 08:13 PM
  #1  
Registered
Thread Starter
 
Join Date: Jan 2007
Location: Charlton, MA
Posts: 7
Likes: 0
Received 0 Likes on 0 Posts
Default Engine Gurus?

Are there any good marine mechanics near Worcester, MA area? Converted my 320efi(350 chevy marine motor) to carb and can't get more than 3500rpm out of it at wot. Rebuilt the motor completely and went 30 over. Full MSD ignition with edelbrock intake and carb. Tuned the motor all last summer and only got about 200rpm best. Tried about 10 different props. Drive is still good. The only part of the motor I didn't change is the cam. Would the stock cam that was for the fuel injection cause that much of a lack in the torque? Boat used to go 60 now only does about 40 tops. The thing is driving me nuts. HELP!!!! PLEASE!!!!
BajaJim737 is offline  
Old 02-06-2009, 08:35 PM
  #2  
Platinum Member
Platinum Member
iTrader: (5)
 
johnnyboatman's Avatar
 
Join Date: May 2001
Location: NO WHERE
Posts: 3,358
Likes: 0
Received 0 Likes on 0 Posts
Default

r u sure u got the timing right, sounds like thats where you need to chk first, is the carb opening all the way?
johnnyboatman is offline  
Old 02-06-2009, 08:36 PM
  #3  
Platinum Member
Platinum Member
iTrader: (5)
 
johnnyboatman's Avatar
 
Join Date: May 2001
Location: NO WHERE
Posts: 3,358
Likes: 0
Received 0 Likes on 0 Posts
Default

what is the rev limiter set at, could be that.
johnnyboatman is offline  
Old 02-07-2009, 01:32 AM
  #4  
Charter Member # 55
Charter Member
 
Griff's Avatar
 
Join Date: Oct 2000
Location: Omaha/LOTO
Posts: 19,545
Received 1,811 Likes on 901 Posts
Default

The stock cam is not causing a problem unless it wiped some lobes or is not installed correctly.

So, EXACTLY what was done to the engine in the rebuild?????? besides going .030 over.

In other words, post all the specs and all the parts used.
Griff is offline  
Old 02-07-2009, 06:08 AM
  #5  
Registered
 
Join Date: Jan 2009
Location: Gladstone Queensland
Posts: 13
Likes: 0
Received 0 Likes on 0 Posts
Default

Just athought.
If MSD is a new upgrade , Check supply voltage wire guage.
Usually needs to be Inreased.
The result is a very lazy spark that will find it hard to produce a good fire at wot.
You never know!
Cheers
bustedarse is offline  
Old 02-07-2009, 08:39 AM
  #6  
Registered
 
Join Date: Apr 2005
Location: Washington, MO
Posts: 1,442
Received 19 Likes on 7 Posts
Default

Originally Posted by BajaJim737
Are there any good marine mechanics near Worcester, MA area? Converted my 320efi(350 chevy marine motor) to carb and can't get more than 3500rpm out of it at wot. Rebuilt the motor completely and went 30 over. Full MSD ignition with edelbrock intake and carb. Tuned the motor all last summer and only got about 200rpm best. Tried about 10 different props. Drive is still good. The only part of the motor I didn't change is the cam. Would the stock cam that was for the fuel injection cause that much of a lack in the torque? Boat used to go 60 now only does about 40 tops. The thing is driving me nuts. HELP!!!! PLEASE!!!!
You obviously had to remove the cam to bore the block. Did you assemble the engine or someone else? With new pistons, what was the change (if any) in compression?

The cam does not care if an engine is efi or carbed.

Like Griff says, we need more info! Help us help you...

Last edited by 4mulafastech; 02-07-2009 at 08:42 AM.
4mulafastech is offline  
Old 02-07-2009, 12:26 PM
  #7  
Platinum Member
Platinum Member
 
fourplaydave69's Avatar
 
Join Date: May 2003
Location: Andover, Ohio
Posts: 134
Likes: 0
Received 0 Likes on 0 Posts
Default

Had a problem like yours many years ago. Found out the two wires from dis. to box were crossed. Worth a try.
fourplaydave69 is offline  
Old 02-10-2009, 06:45 PM
  #8  
Registered
 
Join Date: Nov 2004
Location: wolfeboro nh
Posts: 58
Likes: 0
Received 0 Likes on 0 Posts
Default local shop

robinson marine in boxboro ma. 19782631100. jp, helped me work the bugs out of my 700's . worth calling.. pretty fair on rates.
38tg is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
cloudmaster_321
General Q & A
11
08-03-2008 04:31 PM
jryan26
General Q & A
52
09-20-2004 08:10 PM
Shah Mat
General Q & A
15
06-26-2004 12:22 AM
formula31
General Q & A
5
06-16-2002 04:02 PM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Quick Reply: Engine Gurus?


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

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