Let’s talk oil pumps

[DBcooper]

I am building a new longblock for my 05 GT. I’m going to go with comp 127600 cams and a centri blower. I plan on spending lots of time up in the high rpm range. I don’t want to put the wrong oil pump in. I have purchased a set of boundary billet gears. I’m having trouble determining the differences between the Melling 10340, m340, and the m360 pumps. I know a lot of people go with the GT-500 pump and pickup tube. I’m not opposed to going this route either. Modular head shops website claims that there is a fitment issue between the m360 pump and boundary gears. I also see boundary offers a billet backing plate.

Can anybody shed some light on which pump I should get? And whether or not I would need to go with a billet backing plate? I’m not too worried about cost. I just want to make sure I get the right pump for my application.

 

[07 Boss]

I believe they offer a billet backing plate because the stock plate gets warped after awhile and you lose pressure. I believe this is a weaker point than the actual gears.

 

[drive_55_not]

The M360 is the one for the 3v, it has the 80psi spring and uses the 15/16 tube and it has a cast iron back plate,

The M340 is the 2v pump, it has a 60psi spring and uses the smaller 13/16 tube, You don't want this one.

The 10340 is an upgraded 340 it uses the 80psi spring and 15/16 tube wit the cast iron back plate, This one is essentially the same as the 360 just a different color.

My personal opinion of Boundary gears is, Save yourself the aggravation of having to pull them out later to throw them in the trash ,,, just thrash them now and use the 10340-Billet version if you want billet gears.

I used the GT500 pump with steel plate and cast gears for years without issue and installed the Boundary gears when I did a refresh and within weeks I had a loss of oil pressure, Pulled the oil pump and the gears looked terrible.

Boundary did send me a replacement set and the same thing happened except that time I had a follower come apart and trashed my head.

I'm using the M360 pump now and my opinion is the same as Boss, The pump flexing is probably what causes broken OP gears.




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[DBcooper]

The M360 is the one for the 3v, it has the 80psi spring and uses the 15/16 tube and it has a cast iron back plate,

The M340 is the 2v pump, it has a 60psi spring and uses the smaller 13/16 tube, You don't want this one.

The 10340 is an upgraded 340 it uses the 80psi spring and 15/16 tube wit the cast iron back plate, This one is essentially the same as the 360 just a different color.

My personal opinion of Boundary gears is, Save yourself the aggravation of having to pull them out later to throw them in the trash ,,, just thrash them now and use the 10340-Billet version if you want billet gears.

I used the GT500 pump with steel plate and cast gears for years without issue and installed the Boundary gears when I did a refresh and within weeks I had a loss of oil pressure, Pulled the oil pump and the gears looked terrible.

Boundary did send me a replacement set and the same thing happened except that time I had a follower come apart and trashed my head.

I'm using the M360 pump now and my opinion is the same as Boss, The pump flexing is probably what causes broken OP gears.


Thank you for the response. That’s the info I’ve been trying to find. I have looked at the 10340 with the billet gears. It’s not too late to send my boundary rotors back. Do you think it’s necessary to use the high pressure spring that comes with the 10340? Also, would it be worthwhile to put a stronger backing plate on it?

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[DBcooper]

Thank you for the response. That's the info I've been trying to find. I have looked at the 10340 with the billet gears. It's not too late to send my boundary rotors back. Do you think it's necessary to use the high pressure spring that comes with the 10340? Also, would it be worthwhile to put a stronger backing plate on it?

 

[Midlife Crises]

I thought the 340 pumps were for the 2 valve engines and the 360 pumps with their wider gears and increased volume were for the 3 valve engines with VVT. I’ve been running the Ford Racing GT 500 hi volume pump for several years now. I removed the steel backplate and installed Boundry gears and bolted the same plate back on. I have had no issues with oil pressure .

 

[drive_55_not]

The 10340 has an 80psi spring, 20psi more than the 60 on the 340.

That is the spring the 3v uses.

Yes I would use a pump with a stronger backplate.

The 360 I'm using has 80psi cold start oil pressure and settles in at 25 warm idle and runs about 50 cruising down the road, and 80 WOT.

Since you mentioned the GT500 pump, you can use the pump but you'd need to swap the spring from a 3v pump otherwise you'll have 100psi cruising pressure on a 4.6.

I had to refresh my memory on these pumps, if you are keeping your VCT active, you'll want the M360HV, that's the high volume pump where the higher volume is needed to control the VCT solenoids, My cams are locked so I don't need the HV, probably don't need 80psi either.

I presume you'll be locking your cams with those 600's. I don't know what your plans are but you'll lose 20hp on the top locking the cams out ,

Since you are starting from scratch I'd call Bullet Cams and get a set of cam's cut for lockouts and keep that power , and probably gain some.




./

 

[DBcooper]

I was going to run n/a for a while with the 127600s. I was planning on running the limiters as opposed to lockouts since I’m hoping to get some time on the street and at the strip. Once I get the centri on, I may switch to a different cam. Depends how much boost I end up running

 

[JC SSP]

When I do my chains, tensioners and followers I plan on upgrading the oil pump.

Please confirm. This is the BEST one for 05’ GT NA street car should use.

The M360 is the one for the 3v, it has the 80psi spring and uses the 15/16 tube and it has a cast iron back plate.

Is there anything else needed on the oil pump or is this all I need? So many options makes this a little confusing????

 

[DBcooper]

When I do my chains, tensioners and followers I plan on upgrading the oil pump.

Please confirm. This is the BEST one for 05’ GT NA street car should use.

The M360 is the one for the 3v, it has the 80psi spring and uses the 15/16 tube and it has a cast iron back plate.

Is there anything else needed on the oil pump or is this all I need? So many options makes this a little confusing????

I’m glad I’m not the only one who finds this confusing. Melling has been little to no help

 

[DBcooper]

I wanted to update this thread for anybody interested. After extensive research, it appears that the m340 and m360 are essentially the same pump. The m340 has a 60 lb spring and the m360 has an 80 lb spring. The 10340 comes with both springs AND has a hard anodized coating on the housing. All will accept the 15/16 modular pickup tube. Hope this helps somebody