just wondering? waht if anything would i need to do? i was going to use a new stock oil pump. s this a good or bad idea? i have a stock 400oilpan. with the big front lip seal. i thought of using one after i read a article about this.

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89 firebird formula

356 10.5:1compression CURRENTLY DEAD!!! BEARING FAILURE!!
comp cams xe262 cam
performer rpm intake
#1405 edlebrock 600
sportsman 2 heads 64cc 2.02/1.60 valves 200cc intake runner
msd 6al
h.e.i. proform 50,000 volt vac. advance ditributor
700r-4 with 3.08 first gear and 3.23 posi 7 5/8 rear end.
b trans shift kit(will kill shifts...suck dong!!)
shorty heddman hedders with custom 3" pipe y-pipe back(no damn cat!) with 40 series flowmaster!
griffin daul1" core rad.cutom fabrication to fit(but no cutting )

future mods: 406 roller REALLY REALLY REALLY RADICAL!!!!!

current engine underway..sucks not having a car!! Building the same engine but .060 over balanced and blueprinted..decided to get a little more serious this time around!!

 

i thought they were the same pump but i just looked and they have differant p/n's. i'd guess going by the differant numbers they don't interchange.

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ICON Motorsports

1st & 3rd
MM Black Diamond 538 F&AM

 

Actually it bolts right up. If your old pump was a M55-HVS, that is nothing but a BBC pump with a special screen to fit the old Z28 pan.

Those of us who have been doing this for a while used to use a M77 as a HV small block pump, back before the late Harry decided to make the special version of screen and repack it under the other number. Nobody does that nowadays though, since on a street motor it doesn't really do any good, and in fact does harm. Just like the blown-up motor you're working on, that extra volume of oil doesn't protect the engine from anything when something goes wrong. Where it comes in handy is when you cross-drill the crank, groove the bearings, cut spit holes in the rod cap mating surfaces, etc. etc., all of which increase the engine's internal oil flow. As long as all that is stock, there's no benefit to the 12-tooth pump.

Use a regular M55 with the Mr Gasket spring, part # 26.

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"So many Mustangs, so little time..."
ICON Motorsports

 

Although the pump itself will bolt right up, you should make sure you use the proper screen and that the screen is within 3/8" from the bottom of the pan.

External identification of the pumps is easy. Big block pumps have 5 bolts holding the pump together. Small block pumps only have 4.

Small block pumps have 7 teeth on the gears. Big block pumps have 12.

If you intend to use a big block pump, you should change the intermediate shaft (the one that connects the pump to the distributor). The factory one should have a little plastic sleeve holding it to the pump. Buy an aftermarket shaft that has a steel sleeve.

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Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z Pro ET Bracket Race Car
383 stroker (carbed) with double hump cast iron heads and pump gas
461 Big Block installed and ready for the 2001 racing season

Best results before the 383 blew up
Best ET on a time slip: 11.857 altitude corrected to 11.163
Best MPH on a time slip: 117.87 altitude corrected to 126.10
Altitude corrected rear wheel HP based on power to weight ratio: 476.5
Best 60 foot: 1.662

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
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87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

ok but will a stock bbc pump suck a bone stock pan dry?? what are the chances? ive heard its the high volme part of the pumps that suck the pan dry? also for some reason everyone here uses a m55 with a high pressure spring.(#26) wont that cause the dis shaft to turn too slow and cause a hp loss??



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89 firebird formula

360 10.5:1compression (350 .060 over)/fully balnced and blueprinted
comp cams xe262 cam
performer rpm intake/port matched to heads
#1407edlebrock 750
sportsman 2 heads 64cc 2.02/1.60 valves 200cc intake runner/cnc pocket ported
msd 6al/msd8.5 super condutor wires
h.e.i. proform 50,000 volt vac. advance ditributor
700r-4 with 3.08 first gear and 3.23 posi 7 5/8 rear end.
b trans shift kit(will kill shifts...suck dong!!)
shorty heddman hedders with custom 3" pipe y-pipe back(no damn cat!) with 40 series flowmaster!
griffin daul1" core rad.cutom fabrication to fit(but no cutting )

future mods: 406 roller REALLY REALLY REALLY RADICAL!!!!!

 

Let me, one more time, post a simple equivalence relation:

High volume pump for SBC = BBC pump

Yes, a high volume pump used in a stock motor is inappropriate because it will aerate the oil in the pan. It will not "suck it dry" because there's nowhere in particular for the oil to go that it wouldn't go if the pump was a regular one. Basically a high volume pump on a stock bottom end is a mismatch. Since no higher volume of oil can possibly flow through the engine, the ability of the pump to move any more oil is irrelevant.

The M55 with the Mr G spring is essentially the same thing as a M55A which is the replacement for the stock pump that comes in these cars when they have one of the better motors except with maybe 5 more psi of pressure. Those motors seem to have more HP than the lesser motors. So I could be wrong but I don't think it will cause the motor to have less HP therefore. It can't slow down the dist shaft down any because it's connected to the camshaft by a gear. The reason for doing it this way is that a M55 costs $11 and the spring costs $4 for a total of about $15, but the M55A costs $25.

Like Stephen said, use either a racing oil pump drive shaft such as the Moroso one, or use a Melling IS55-E which is the same thing for about half the price. You should always do that no matter what pump you use.

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"So many Mustangs, so little time..."
ICON Motorsports