radd

Should i replace my oil pump i have the motor out of the car at the moment and could do it easily 62k on current one

My last motor died because oil pump failed.

if yes
What should i get?

made by melling

i have seen a few diffrent types

1. one is high (15-25psi over stock) psi and (25%)volume

2. just high volume 25%

3 high psi 15 - 25 psi over stock

matt94z

iTrader: (49)

I replaced mine when the motor was out of the car, just for peace of mine. I used a stock oil pump, plenty enough. I wouldn't use a HV pump though, you might suck the pan dry. If you want to upgrade just go with a high pressure standard volume.

radd

this is hard to figure out because ive heard both ways

someones reply on another forum
Ok, oil pressure is not created by the pump directly. It is created by the clearances on your bearings. IE looser bearings cause lower pressure. Now, what keeps your oil pressure from going up forever is one of two things. The pump relieve valve opens or the characteristics of the pump itself become a restriction much like a set of stock heads with a aftermarket cam. With a high volume pump basically all it does is just push more oil through the system and the oil pressure relief valve opens at the same PSI as stock. A high pressure pump is a waste because a motor only needs about 10 psi of oil pressure per 1000 rpms to be properly fed. Just go with high volume and you'll be ok.

383LT1S10

Exactly! I second the High Volume and make sure you use the oil pump driveshaft with the intregal steel retainer. Not the cheap plastic one.

buffman

iTrader: (9)

yeah ARP driveshaft is Cheap. Like $16.

IMO from what I've read high volumes aren't needed. They can be used just fine with a stock pan, as long as you're still using the windage tray. I'm going to be replacing mine soon because the oil pan gasket is leaking and I figured what the heck. I was recmmended to use the canton "high" pressure spring (I think 10-12psi) over stock. I need to get my mechanical test gauge finished so I can see if my autometer oil pressure guage is lying to me.
Matt

96capricemgr

iTrader: (1)

Depending on your usage a stock pan and a HV pump can lead to oil staravtion and a blown motor as repayment for you halfassed "upgrade" with a stock pan use a stockish pump, if you upgrade the pan then it should be safe to run a HV pump but it is still unecessary. The LT1 oiling system is pretty good bone stock.

383LT1S10

Having prolly built over 30 motors of various makes and sizes, I have used a high volume pump in every one of them that had that as an option. Running the pan dry is a ******* urban myth or the sign of blockage in the heads and lifter valley. Maybe if you were turning 8,000 rpm's all damn day you could too. Put the Melling Part#HV55 (about $30 at most parts stores) and a melling part#IS-1 ($8 I think thats the part# I will check later). i'd recommend having the pickup tack welded to the pump body so it doesn't work loose either and cause an oil starvation issue. I dare you to show me anyone whos ran their pan dry with a high volume pump and there wasn't some other issue that caused it, you can't.

buffman

iTrader: (9)

^^ I'd have to ask one of our ISSF members, but I think he did while roadracing his 383 with a HV pump in the stock pan, with no windage tray.

matt94z

iTrader: (49)

I've had several engine builders steer me away from HV pumps with a stock pan, but let us know how that HV works out for ya. Also I've been told that the HV steels a few hp also. I guess it could all be "MYTH'S" though

96capricemgr

iTrader: (1)

As Matt said it has happened to a couple of the Impala guys I said DEPENDING ON USAGE and with a stock pan. They were road racing big sweeper turns keeping oil in the valvecover sustained higher rpms pumping oil uptop.

Guys have also had issues with the increased load on the oilpump drive damaging the gear.

While crying for proof why don't you show me one shred of evidence that shows it is anything but a waste of money and HP.
The stock LT1 pump is a step above the old smallblock pumps anyway so even if an old gen1 stocker was crap that does not apply here, neither does any other make or model.
Tell you what when I put my Briggs & Stratton together all it needed was slinger, no pump atall so all this talk of pumps in a totally different engine must be silly anyway since that engine doesn't need one no engines need them . That is about the depth of the logic you offered

383LT1S10

First your entire post is ignorant since they Gen 1 and Gen 2 Smallblocks USE THE SAME ******* PUMP stock. Go look up at a parts store, they both call for a melling part#M55 (I run a parts store I sell a dozen a week).

Second, this ******* topic has been beaten to death on chevytalk.com and guys who build 800hp big blocks will agree that unless you are turning extreme rpm's for extended periods of time you will not suck a pan dry if the pump is installed properly and the pick up is installed properly.

I'll stick to my experience versus your so called "knowledge" from the net..

Though if you are ******* **** about it you can run a STOCK Big Block pump on a smallblock using the high volume smallblock (5/8" or 3/4 I can't remember) pickup screen.

And if a high volume pump is "stealing hp" from your engine enough for you to worry about your engine must suck ***** anyways and I would be worrying more about other things than the friggen oil pump.

96capricemgr

iTrader: (1)

LT1s and gen1 use the same REPLACEMENT pumps, the stock pump is better than older gen1s got from the factory. When an LT1 becomes a 800hp bigblock then that big block experiance might come in handy. Keep making my point about how your are trying to apply OTHER ENGINES issues to the LT1.

You run a parts store is your claim to knowledge thank you again. How many here have actually met a parts store person they would call genuinely an expert in any particular model, occassionally you will meet a "jack of all trades master of none" but usually I wouldn't trust those guys to change a lightbulb. Like the guy who told me I needed a Lingenfelter intake and bigger injectors on my stock Caprice . Few true gearheads are capable of dealing with the ignorance of the average parts store customer, it drives them wild and they get out.

383LT1S10

Stop acting like the ******* LT1 is some exotic ultra performance engine. Its a ******* smallblock with a few quirks. What applies to a ******* stock 250hp 283 will often apply to a ******* LT1. Aside from the opti and a few odds and ends its the same ******* principles. But, then again I doubt you have much knowledge with much aside from your little car there so you're forgiven.

I will let my 5 ASE Certifications speak to my ability and knowledge..Wheres yours?

ENGINE PERFORMANCE
ENGINE REPAIR
BRAKES
STEERING & SUSPENSION
PARTS SPECIALIST

4+ years of Gm Dealership experience
6+ Years in the parts business

Flash99

iTrader: (48)

WOW, waiting for any type of response on this...

generic2600

This is pretty out of hand.

383LT1S10

You're right and I appologize guys

radd

Aww and i just turned off the tV!!

radd

Thanks for the help guys! HV pump is on the way

96capricemgr

iTrader: (1)

The LT1 is pretty much just a smallblock WITH SOME ADVANCES. I understand what it is. I was not the one trying to say because a big block needas something this engine needs it.

96capricemgr

iTrader: (1)

I was thinking maybe the b-body in radiator or in front of the radiator oil coolers are a part of this as far as why some guys have had problems, f-bodies use coolant routed to the filter adapter right? Seems that is a fairly signifigant difference in the lube circuit.

Still though I would like to see a case where a HV pump was actually shown to be of any help on a shortblock with stock like clearances. If the builder sets it up for a HV pump with loose bearings them you have little choice.