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My 69 351W is coming out of the engine rebuild shop next week. The shop is telling me NOT to use a High Volume oil pump. They said it simply is not needed. He even mentioned it may be bad for the engine. My only modifications are .40 over, Comp Extreem cam ( mildest one ) and lifters, and new valves. I am planning on using a high preformance water pump. Edlebrock RPM manifold and 600cfm carb. Wouldn't a high volume oil pump be a good idea?
 
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it's a mixed bag. There are many now who speak out against it. It is harder to spin and may not be needed. However, I have used one on every engine I have built for the last 15 years, and as far as I know, they are all still running /forums/images/icons/blush.gif)
 
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it's a mixed bag. There are many now who speak out against it. It is harder to spin and may not be needed. However, I have used one on every engine I have built for the last 15 years, and as far as I know, they are all still running /forums/images/icons/blush.gif)
Use a better oil pump shaft too.
 
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The rational for not using one that I have heard is that it loads up the distributer gear. You have a better chance of grinding up the dizzy gear and tossing about shavings or having it fail completely.

But thats just what I've heard.
 
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No, you don't need a high volume oil pump. Most all small block fords carry more than enough oil pressure with just a stock pump. Sometimes a high volume pump will pump oil faster than it can drain back into the pan, and creates problems. The best engine builders in San Diego recommend against using a high volume pump in a "street" engine.
 
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My machine shop also recommended against using one of these. Both for the distirbutor issue and that they (high-pressure pumps...) are only really necessary for racing situations. They explained it by stating that too much oil gets pumped to the top surface of the engine, therefore, starving the lower side since you are not running at high RPM's.

I opted not to go that route and have a similar rebuild as you described....
 

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I have run a HV pump in my 5.0 engines, and of course the 69 Boss has one stock. From what I understand the HV pump was provided in the Boss to keep enough oil flowing through the #4 rod throw in the crank at high RPM. It is true that the wear on the distributer gear is accelerated and I try to keep an eye on mine but my 5.0 has about 50k miles on the dist gear (roller cam steel gear) and still looks fine. My feeling now is that I probably don't need the HV pump in the 5.0 but I also have not run into any problems.
 

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If the shop didn't increase your rod and main clearances for high rpm use, then a blueprinted stock pump is fine.

Any oil that doesn't go through the galleries gets dumped out the pressure relief, so, if your hot pressure is lower than the cold pressure at engine speeds above idle, the pump capacity is at or below the needs of the engine. Temperature has a minor effect on the pressure relief, but it isn't significant.

I run the engines in the race car pretty loose and get about a 5-10 psi drop from cold to hot, with ultimate pressures in the 55-60 psi range. This is adequate for operation under 7K rpm, which is within the operational parameters of the engine.

Your shop knows how they built the engine and what is best for it, oiling-wise; I recommend trusting their judgement. They'll be the ones to warranty the engine if they screwed up...*G*

BTW, I concur with cobrapatrol.....I've never eaten a distributor gear in my 20+ years of building engines...and some of the early 289/302's were running pressures of over 70 psi to provide adequate lubricating spinning into the high 7K range. Personally, I think materials have deteriorated over the years as companies cut costs to be more competitive. I still have some of the early distributors out in the shop so I'll have to re-visit the gears and can post detailed pix if requested.

Lastly, I recommend running a good quality multi-viscosity oil, at least to break in the engine. In the race car and my other Pony, I run 10W-40 for winter operation and 20W-50 the rest of the year. Additionally, having a cooling system which brings the lubes up to temp quickly can help lengthen engine life; this drives off moisture and volitile contaminants which otherwise can damage engine components in the long term.

Just so you don't get too worried if your opinion differs from the shops, the first engine I built (myself) was very similar to the one you're building and yes, it did have a good old Melling HV pump in it, along with a Milodon deep pan and Boss 302 windage tray. Very mild engine which spun to 7K and ran 14.00's....drove it and raced it from 1977 to 1984 (stopped racing mostly by 1980 when I bought the race car); put nearly 40K miles on the engine in total and never had a bit of oil system or distributor-related problems (other than the dang Unilite *G*); only problems I can recall were a couple of broken screw-in rocker studs (back in the days before roller rockers).

Good luck with your new engine!
 
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High volume pumps and high pressure pumps are two completely different animals. Some of you are comfusing the two.
 

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Thought I would throw my .02 cent in bing I am running a Cleveland and its "history" of oiling problems. I am running a HV pump restrictors ( yes, with hyd. lifters) to keep all that oil from sitting in my heads due to poor drainback, and a bronze dizzy gear. I'll just keep an eye on the bronze gear and replace if needed.. that simple. The HV pump is just a safeguard aginst any of the supposed Cleveland oiling problems. Ask a million Cleveland owners and you will get a million answers. Evything from external oil lines to sleeving the lifter bores. Clevelands are spun higher than most engines and also were installed in Pantaras, which could pull close to 1g lateral which would put all the oil on the side of the pan. Besides that I see no issue in the C's oiling system.

In your case I would I would make sure your shop puts in a good quality STOCK oil pump (melling) and rest assured.
 

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Yeah, I agree Pete....some users get the HP and HV pumps confused...

All else being equal, HV pump will take more HP to run, at the same pressure, compared to a stock or HP pump with stock displacement. I experimented years ago with an adjustable pressure relief on the Melling HV pumps I ran in my early racing engines and that was how I achieved the 70+ PSI I ran in those engines. With the rod and main clearances I was running (this was before I learned how to restrict the oil galleries), a regular HV pump just wouldn't make the pressure that I felt comfortable with when spinning the engines to over 7K...especially that long pull in high gear, as I ran 5.14's and a 5K stall converter.

Something that wasn't mentioned was the pump drive and its ability to transmit the HP required to drive an aftermarket HP or HV pump. Although many VMF'ers don't like the 4130 drives, I prefer them and have used them since the late 70's. Oil pumps, other than my experiments with pressure, have largely been a non-issue in my operations. I pull them apart, blueprint them, run them up on my hydraulic test bench (I repair hydraulics for a living) and put them into service.

Hopefully, our poster's shop does the rudimentary checks and blueprinting on his pump...I just hate taking engines apart..*G*
 
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