[Tom Vaught]

Originally Posted by Old Goat Racer

Around 1980 I bought a 71 Catalina parts car for $100. It had a 455 with a 2-barrel carb YG code.

I have seen at least two of the FACTORY 455 2-BBL 71 Catalina vehicles/ engines that were put into service pulling a Airstream trailer.

Tom V.

[1968GTO421]

I bought my GTO several years ago from a young couple who moved to this area from Salt Lake City, Utah (a job transfer). The wife's father was a big GTO fan and encouraged them to have at least one GTO so they could know "The Great One". They bought their GTO while in Utah around 2009 from a guy in Coeur D'Alene, Idaho. (Allegedly a GTO expert/restorer.) They wanted an iconic car but, with a new baby, sold the GTO for a new SUV with full infant safety equipment after putting 9000 miles on the GTO.
They had the man (Rod Hollen) in Coeur D'Alene Idaho rebuild the non-original 428 engine for them. I found the engine number (9792068) behind right cylinder head and with the help of Ames tech guys learned the date and XF made it a '69 Grand Prix 428----all good. (GTO also has the '69 and up single piston disc brakes replacing the original 4 piston calipers.) Despite being a '69 engine, it has the 8 bolt timing cover/water pump, 067 cam, and 6X-4 heads. The intake is a Performer with a leaky Eddy carb. (I have a SMI q-jet to replace it.)
I had questions the sellers couldn't answer about the engine "rebuild" so they gave me the name and email of Rod Hollen in Coeur D'Alene who did the work for them. I sent him several emails w/pic of the car and the PO's names with my questions, None bounced back, and he never ever replied.

The sellers had used the same oil in the GTO for oil changes as for their new cars --- 0W20 synthetic and Fram oil filters. At idle the Autogage oil gauge read <20lbs. I changed it 2X for a new Wix filter and 20W50 Pennzoil. Still never goes over 40 psi. Led me to wonder if the 40 psi pump was used in the rebuild. I've listened to the engine with a long screw driver and a 1/4" vacuum hose but haven't heard any knocking or other bearing noises. I've wondered about a fictitious engine rebuild or crud in the oil pump pickup. Yes, pulling the pan and looking at the pump and bearings is the solution but when I retired 15 years ago I gave away my big tools like engine hoist, engine stands, big floor jack (I have the little one still) and other related stuff

(I had a '53 Mopar flathead six years ago and was able to pull the oil pan with the engine in the car with no trouble and not raising the engine.) A friend wondered if I pulled the GTO distributor if there would be clearance to raise the engine enough to pull the pan for a look

My Thanks to everyone for your advice and all the info supplied!

[b-man]

Originally Posted by 1968GTO421

I bought my GTO several years ago from a young couple who moved to this area from Salt Lake City, Utah (a job transfer). The wife's father was a big GTO fan and encouraged them to have at least one GTO so they could know "The Great One". They bought their GTO while in Utah around 2009 from a guy in Coeur D'Alene, Idaho. (Allegedly a GTO expert/restorer.) They wanted an iconic car but, with a new baby, sold the GTO for a new SUV with full infant safety equipment after putting 9000 miles on the GTO.
They had the man (Rod Hollen) in Coeur D'Alene Idaho rebuild the non-original 428 engine for them. I found the engine number (9792068) behind right cylinder head and with the help of Ames tech guys learned the date and XF made it a '69 Grand Prix 428----all good. (GTO also has the '69 and up single piston disc brakes replacing the original 4 piston calipers.) Despite being a '69 engine, it has the 8 bolt timing cover/water pump, 067 cam, and 6X-4 heads. The intake is a Performer with a leaky Eddy carb. (I have a SMI q-jet to replace it.)
I had questions the sellers couldn't answer about the engine "rebuild" so they gave me the name and email of Rod Hollen in Coeur D'Alene who did the work for them. I sent him several emails w/pic of the car and the PO's names with my questions, None bounced back, and he never ever replied.

The sellers had used the same oil in the GTO for oil changes as for their new cars --- 0W20 synthetic and Fram oil filters. At idle the Autogage oil gauge read <20lbs. I changed it 2X for a new Wix filter and 20W50 Pennzoil. Still never goes over 40 psi. Led me to wonder if the 40 psi pump was used in the rebuild. I've listened to the engine with a long screw driver and a 1/4" vacuum hose but haven't heard any knocking or other bearing noises. I've wondered about a fictitious engine rebuild or crud in the oil pump pickup. Yes, pulling the pan and looking at the pump and bearings is the solution but when I retired 15 years ago I gave away my big tools like engine hoist, engine stands, big floor jack (I have the little one still) and other related stuff

(I had a '53 Mopar flathead six years ago and was able to pull the oil pan with the engine in the car with no trouble and not raising the engine.) A friend wondered if I pulled the GTO distributor if there would be clearance to raise the engine enough to pull the pan for a look

My Thanks to everyone for your advice and all the info supplied!

Take the engine out and put it on an engine stand and just replace the oil pump. Buy or borrow the big tools you got rid of prematurely. Sell them later if you feel the need or don’t have the room to keep them.

Once you undo everything needed to get the pan off with the engine suspended and halfway out of the engine compartment and then go through the contortions of removing the pan you’ll wish you never went that route. Really the worst way to go about it.

Trust me.

Final word of advice: If it ain’t broke don’t fix it.

[Jay S]

If it never goes above 40psi I would say it definitely has the 40 psi pump. As long your 428 has decent pressure at idle and hits 40 by normal cruising speeds I would not go back into it too swap out a pump for a 60.

I have a 72 455 2bbl engine that was all original and it had the 40psi pump and small 5/8” pickup. I think generally if a 400 or 455 had small valve heads it had a 40 psi pump no matter what the cubes were. I could be wrong, as TV said many of these old engines have been gone thru at least once and have the 60 lbs pump now. I seem to recall that a 1970 455 with 15 heads had a 40psi pump. Some big valve engines like the 350 4Bbl and standard 400 4bbl in the mid to late seventies had the 40 lbs pump too.

I don’t know if it was mentioned anywere here, but the 60 lbs pump also used a stronger alloy pump drive shaft.If you swap out a pump from a 40 to 60 that needs to be switched also.

I would only be concerned about needing the bigger pump if it did not carry 40 lbs of oil pressure at cruising speed, and or you have a really have foot and like to cruise at above 4000 RPM all the time. Pontiac didn’t send any 4 bbl cars out with a 40 psi pump and 4.30 gears.

[1968GTO421]

A big thank you to Bart and Jay for their advice on oil pump replacement Since the 428 has a 066-067 cam (the previous owners asked their builder for good gas mileage they told me) I'll just use 4 grand as my redline for now until I can do a quality job on the engine oil pump and rear main seal. I can worry about new tires for my 15" wheels for now.

[Tom Vaught]

If you look at Bill Hanlon's post #17 you will see that you can't bolt up a M54 D series oil
pump to a M54 oil pump block. The mounting locations are different.

http://forums.maxperformanceinc.com/...2&d=1397610756

So if you have a 455 2 bbl engine oil pump system, you are stuck with the small tube
oil pump screen and smaller flow passages and 40 psi pressure.

Tom V.

[1968GTO421]

And I want to thank everyone for their input on this oil pump subject. Lots to learn here. I appreciate everyone's input and thoughts!

[Cliff R]

I can't remember specifically the part number or date range but the Melling oil pumps used to come with the 60 psi spring installed in the pump and a spare 40 or 45 psi spring in the box. I've personally never used the lower pressure spring in a Pontiac build but always use the lower standard volume/pressure Melling oil pumps in SBC engines. The heavier mass/weight of the Pontiac internals and larger journal diameters justify the 60psi pump IMHO and that's all I've ever used here for my Pontiac engine builds......

[Tom Vaught]

A lot of "Farmers" Pontiac Vehicles/Engines never saw 3900 / 4000 rpm in their life on the road.
So the 40 psi pump (with the different bolt oil pump pattern) to the block on the engines with 2-BBL Rochester Carbs made perfect sense.

I have seen one case where the 66 389 engine had the 60 psi oil pump & block BUT this was on a Ambulance
(built as a second unit/body with a factory 2 BBL carb set-up and 1.92 intake valve heads. Pontiac sold a bunch of second unit/body engines to
Ambulance/Hearst vehicle builders.

Tom V.