High Volume Oil Pump

[Tiger81269]

I'm doing a 3100 rebuild (camshaft broke at 165,000 miles and figured what the heck I'll rebuild the thing)!

The question I have concerns the Oil Pump!
I see there are 2 different choices.
The OE style pump and a High Volume Pump is available.
Can anyone tell me the difference in Pressure between these two options?

And any known negative side effects?

I've done this kind of an improvement on the Traditional PONTIAC V8 (higher pressure is recommended) but not on anything newer than 1979! lol

Any Thoughts?

[60dgrzbelow0]

There are two possible negative consequences of employing a High Volume Oil Pump that bear mentioning; one comes to you from John (Forced Firebird) on an inquiry I made of him some time ago on this very subject and the other will be important depending upon where it is that you live in the USA:

(1) High Volume Oil Pumps tend to pump excessive amounts of oil into the top end of the motor at higher RPMS...and if you are doing anything involving high performance driving such as racing and navigating through various high speed turns...or in the case of the sudden change in position of the static fluid in the crankcase when the clutch is dropped and the car lurches forward... the Oil Pick Up tube might scavenge air for even just a moment if the fluid levels are not topped off properly..engine death occurs soon afterward.

(2) In very cold temperatures and with thicker viscosities of motor oil...the labor on the oiling system is enormous when the engine is cold...and since all wet-sump motors begin with most of the oil draining to the bottom of the oil pan...the larger gears inside the HV Oil Pump will labor greatly against the resistance of dense, cold oil when trying to get the stuff from the bottom of the oil pan...pumped up inside all of the oil galleries and parts... soon enough to do their proper good. Think of the Larger Gears as just more metal surfaces that need to overcome the thickened, reluctant goo and get it to move before the engine gets up to proper operating temperature. Early and dramatic engine wear results...each and every time the engine is started in the deep cold. Take pity on your car battery and starter motor!

[60dgrzbelow0]

This Melling Video will go a long way in explaining the difference between Oil Volume versus Oil Pressure:

http://www.youtube.com/watch?v=7IpJlYssvkM&feature=PlayList&p=5AFDD0D5E4A7EA1D&playnext=1&playnext_from=PL&index=1

[1988GTU]

I wouldn't rebuild that motor. Pitch it and start with a good runner.

[geoffinbc]

Keep the stock pump. They are more than adequate. The only thing I would ever do for a high performance motor that would see frequent use beyond 6000RPM is to add a stiffer pressure spring. But the stock pump will put out 60 PSI with full temperature oil by 2000RPM and thats more than required. A HV pump will just piss more oil past the bypass spring and jut entrain the oil with air and heat it up.

[Tiger81269]

I wouldn't rebuild that motor. Pitch it and start with a good runner.

You wouldn't believe how hard it has been trying to find an engine.
I'm near Cleveland and searched since Thanksgiving (when the motor blew up) for a 100 miles radius. Nothing but one 3400 with 180,000 miles for $800!! Every place I called all said the same thing.. "I don't have a GOOD motor to sell you"
it seems the 3100 & 3400 engine is plagued with Camshaft and Intake issues.

Ultimately I found another 1998 Grand Am (GT model) 3100 with 126,000 miles for $700. Not running too good due to Blocked EGR, one bad Fuel Injector, and both mufflers rotted in half. After some repairs it seems to have been a good buy other than the badly faded red paint. I'm replacing the intake gaskets for peace of mind (found out they had already been replaced seems to have been a factory repair - GM gaskets - but the mechanic only tightened half the intake bolts and 2 were missing!!!)

So I still have this 1998 Grand AM SE without a motor... So let's fix the blown engine (other than the cam, one bent valve and push rod, there is very little wear!!!) Rod and Main bearings still plastigage in spec!!

I'd like to hot rod the little engine a little and then swap it into the GT and thus putting the GT engine into the SE.

It's a learning experience for me and fun (other than how incredibly hard it was getting the engine out of the car! And who was responsible for the serpentine belt?? Remove the engine mount?? Your kidding!! Makes me appreciate my 68 GTO even more!!)

[Tiger81269]

Keep the stock pump. They are more than adequate. The only thing I would ever do for a high performance motor that would see frequent use beyond 6000RPM is to add a stiffer pressure spring. But the stock pump will put out 60 PSI with full temperature oil by 2000RPM and thats more than required. A HV pump will just piss more oil past the bypass spring and jut entrain the oil with air and heat it up.

That's what I've been wanting to hear!
Of all the Grand Am/60 degree V6 forums I couldn't find any info on the oil pumps.

Plus the Std. Pump is about half the price of the High Volume!

Thanks Everyone for ALL the feedback!!

[Tiger81269]

This Melling Video will go a long way in explaining the difference between Oil Volume versus Oil Pressure:

http://www.youtube.com/watch?v=7IpJl...rom=PL&index=1

Thanks...

This one is good info for the neubie too...

http://www.youtube.com/watch?v=tOiHdIXVWE8

[1988GTU]

Goodluck with those cam journals and I'll cross my fingers for longevity for that motor.

[Tiger81269]

Goodluck with those cam journals and I'll cross my fingers for longevity for that motor.

They have been checked. Cam Bearings have been installed. But it was close on #3 journal. The bearing was paper thin but didn't spin. All the cam bearings were scored and grooved very badly as were the Cam Journals.

If I could have found a decent engine for under $400 I would have went that route. I was even toying with the idea of shoehorning a 400 CI Pontiac V8 into it!! LOL. I can pick those up for around $200 in running condition with a TH400 transmission! But the car isn't worth the conversion! Poor girl that owns it doesn't have the money to get another car and she just paid someone $500 to replace the leaking intake gaskets 1 month prior to the cam breaking! The mechanic should have told her what was found!

I'll left ya all know how it turns out.

[robertisaar]

And who was responsible for the serpentine belt?? Remove the engine mount?? Your kidding!! Makes me appreciate my 68 GTO even more!!)

buy a w-body with a 3x00 and you won't have to deal with that issue... lots more room as well.

[pocket-rocket]

buy a w-body with a 3x00 and you won't have to deal with that issue... lots more room as well.

I would rather have the Goat >.>