Ok I know that alot of you people have seen my dyno sheet and have also noticed that my oil pressure is a "tick" on the high side....

So I know that this has been asked before but can you just inner change the spring and nut from a m54d to a m54f to lower the oil pressure? I am obviously running the m54f pump and have lots of oil pressure, and everybody keeps telling me I do not need that much pressure including the dyno operator. I have a m54d 60lb pump sitting on the shelf that I can take the spring and the spring nut out of and put into my m54f pump that is currently in the engine, the check balls are the same size in the pumps, actually everything seems to be the same with the exception of the bypass check ball being about .030 shallower in the m54f pump. This would mean that with the 60lb spring in the pump it would actually be preloading the spring about .030, so I would just end up with a slightly higher pressure than 60lbs but alot less than the current spring....correct? Now I suppose you are saying "why doesnt he just change the pump itself?" well the reason I do not just change the pump is because I have the canton road race pickup already pressed into the m54f housing and its is really tight and I do not know that I could get it out without recking it. Well any help would be great. Thanks

Chad Dammen

ND's fastest Pontiac (I think) and Minot's fastest street car (not like that means much)

Ok I know that alot of you people have seen my dyno sheet and have also noticed that my oil pressure is a "tick" on the high side....

So I know that this has been asked before but can you just inner change the spring and nut from a m54d to a m54f to lower the oil pressure? I am obviously running the m54f pump and have lots of oil pressure, and everybody keeps telling me I do not need that much pressure including the dyno operator. I have a m54d 60lb pump sitting on the shelf that I can take the spring and the spring nut out of and put into my m54f pump that is currently in the engine, the check balls are the same size in the pumps, actually everything seems to be the same with the exception of the bypass check ball being about .030 shallower in the m54f pump. This would mean that with the 60lb spring in the pump it would actually be preloading the spring about .030, so I would just end up with a slightly higher pressure than 60lbs but alot less than the current spring....correct? Now I suppose you are saying "why doesnt he just change the pump itself?" well the reason I do not just change the pump is because I have the canton road race pickup already pressed into the m54f housing and its is really tight and I do not know that I could get it out without recking it. Well any help would be great. Thanks

Chad Dammen

ND's fastest Pontiac (I think) and Minot's fastest street car (not like that means much)

chad...try this, It may help you from all the swapping of springs and stuff.
take your pump out, remove the cover and gears. find a 6 or 12 point socket that will fit loosely in the tube bore of the pump housing but will also seat over the tube of the pickup. Using a C-clamp with the stationary end over the socket, carefully press-out the pickup tube from the body.

1973 SD455 T/A
1979 S.E. T/A
http://community.webshots.com/album/16587603rOyvmFCiHs

You can interchange the spring and nut between the 54D and 54F pumps with out any problems. http://forums.performanceyears.com/g...on_biggrin.gif

with out questions there can be no answers

1969 Grand Prix
[email protected](1.358)
[email protected](1.342)
WARPed Tepee Forums
[email protected]

Ok that is what I figured... Now the next question is how much pressure do I need? Will the m54d have enough pressure for my application? Main clearance is .003 and the rods are .0025. I have the 4.25" stroke with 13.2:1 compression. I have done a search on oil pumps and it seems that everybody has their own idea on what pump to run. All I know is I would rather not contact a bearing. With the oil hot and my current pump I always had 100+psi at 6500rpm. Thanks again

Chad

ND's fastest Pontiac (I think) and Minot's fastest street car (not like that means much)

In my last 469 I would have 130# through the traps. That was with the 80# pump. I kept the same pump for my 482 but I put the green spring in from a 60#pump. I hope it works.......

ask these guys some questions..............

http://cgi.ebay.com/ebaymotors/ws/eB...&category=6770

1973 SD455 T/A
1979 S.E. T/A
http://community.webshots.com/album/16587603rOyvmFCiHs

I also used to run the M54F pump on my old motor and did not like how high the oil pressure was, now I am running a M54D pump shimmed with a washer (just a standard washer that will fit in cap that holds the spring in). With .0025-.003 rod and main clearance I have 20 psi hot at idle with 10W40 oil. Running 20W50 I had closer to 30 psi at idle. At high RPM it is putting out about 70 psi. Based on my experience I think the M54D pump will be fine.

My Sealed Power has about the some with those typ clearances.Son's 400 with tighter clearances and a Mellings 60 lb has 40 at idle and goes to 60 right off idle.