LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

HV oil pump spring in a M155 oil pump

Thread Tools
 
Search this Thread
 
Old Jun 19, 2007 | 11:38 AM
  #1  
BgGy_Z28's Avatar
Thread Starter
Registered User
 
Joined: May 2006
Posts: 8
HV oil pump spring in a M155 oil pump

I'm sure this has been beaten to death, but.

I now have 50 mi on a fresh 383 stroker. I had the builder put a HV oil pump on, only to search here and find out I should leave the stock size pump on with a stock pan. I removed the HV pump but seeing as the builder welded the pickup tube on, I just switched the casing. So I now have an M155 pump with the HV spring inside.

What info I'm looking for is: Should I remove the spring and put in the white spring from GM or is the HV spring just as strong. I have no problem with pulling pan again, just like to know.

I'm not really happy with the pressure as is, but builder and other unbaised builders are telling me it's normal. ( It's at the rule of thumb average- 10psi-1000rpms ). Just don't like it near the red while at a stop light.

Thanks in advance, Allen
Old Jun 19, 2007 | 11:48 AM
  #2  
seawolf06's Avatar
Registered User
 
Joined: Jul 2004
Posts: 3,034
From: Raleigh, NC
Difference in volume is achieved through different internals of the pump, gears I believe. Difference in pressure is achieved through the spring. It allows a higher pressure to build before bypassing it.

Standard spring in the HV pump is same as stock spring. The white spring will increase the pressure. They both probably have the same strength.
Old Jun 19, 2007 | 12:14 PM
  #3  
wrd1972's Avatar
Registered User
 
Joined: Aug 2005
Posts: 4,405
From: Kantuckee Yo'
If your pressure is near the red at the stoplight on a new engine you have bigger problems to deal with. Sounds like bearing clearances are a tad big. The spring does nothing when the engine is at idle. At higher RPM's the spring will open to bleed off excess pressure.
Old Jun 19, 2007 | 12:19 PM
  #4  
Z28SORR's Avatar
Registered User
 
Joined: Jul 2002
Posts: 3,768
From: Friendswood, TX, USA
What weight oil are you using? If the engine was built to the "Old" race specs., you may have to run a 20W50 weight oil.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
HectorM52
Parts For Sale
26
Jul 30, 2017 11:46 AM
89 iroc zl1
3rd Gen / L98 Engine Tech
0
Jan 14, 2015 02:18 AM
BIGCOWL-IMP
Parts For Sale
0
Dec 19, 2014 06:59 AM
Zone
Midwest
6
Jul 29, 2002 07:43 PM
dmaastr
Automotive News / Industry / Future Vehicle Discussion
9
Jul 1, 2002 02:22 PM




All times are GMT -5. The time now is 10:43 PM.