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Discussion Starter #1
Hey all,

My engine has been built for at least 20 years now as that is when I got the car. We put a cam, lifters, springs, and timing chain in it shortly after that but that is as deep as I have been into it. I have a LOT of clean up I want to do to the engine as she is not as pretty as she once was so I am going to pull it out. There are also some oil leaks that I want to get all straightened out and do some inspection.

The engine is:
1969 YS block
62 Heads
292 comp cam
HEI ignition
Recently rebuilt quadrajet (using Cliff's book)
Performer RPM intake
Hooker headers
Saginaw 4 speed

Runs pretty strong.

I know some will probably say this is dumb but I want to tear it down most of the way (short of removing the crank and cam) to inspect everything while I have the engine pulled out. I am also going to put on some roller rockers that I have had for a while (stock ratio) and am considering installing a DUI distributor.

So after all of that, here is why I am posting. I really want to make sure I go with the best gasket set for everything from oil pan to valve covers. Any recommendations? Also, other than just inspecting the engine, are there other suggestions of what I should do while I have it torn down? Any tips or tricks I should put in place or commonly wore parts that would be good to replace now?

Thanks for reading!
Nick
 

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Hi Nick,

You didn't say where it's leaking from? If the rear main is leaking, you're probably going to have to pull the crank...

On my most recent build I used the BOP 1-piece oil pan gasket. I like it a lot. It's a steel core gasket that's encased in rubber with ribs on both sealing surfaces. The steel core keeps it from 'squishing out' when you tighten all the bolts.
For valve covers, I used the Edelbrock 7590's. For intake manifold, I used the Felpro's that have the raised silicone sealing bead around the ports. For headers, I really like Remflex. For the rear main, I used one of the new BOP 1-piece seals. I had trouble this time getting mine to seal, mostly because of the (mis)shape of the aftermarket oil pan I'm running. To make sure, I put the engine together, filled it with 2 gallons of oil, and hung it from my hoist "butt down" to make sure the entire rear of the crank was submerged in oil for two days to see if it was going to drip. It took me a few tries because of the pan, but I did finally get it sealed up.

I used the good GM silicone gasket sealer - the kind that comes in a tube and needs a small 'caulking gun' to apply - on just one surface of the few gaskets where I used any sealer at all. One of the tricks is to apply a small bead of the stuff (don't go crazy, you don't want globs of it squishing out where it can circulated around in your oiling system), install the parts with the bolts LOOSE (just tight enough so that the sealant is touching both surfaces), let it cure for about an hour to start firming up, then tighten the bolts. If you don't have an inch-pound torque wrench, get one. It's not hard to overtighten the pan bolts and valve cover bolts enough to dimple them and cause leaks. I also put small dabs of it in the "corners", like where the timing cover, block, and oil pan meet and also where the heads, block, and lifter cover meet.

Bear
 

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Discussion Starter #3
Hi Bear,

Thanks for all the gasket info. I am not EXACTLY sure where all it is leaking from yet. After looking last night (was labeling the different wiring in prep of the pull) I noticed it is leaking from the front of the oil pan and also the bottom of the front of the trans is wet with oil. Would that be the rear main?

Of course the valve covers and headers are leaking as well. How about replaceable parts while I am that deep in the engine? I guess I might have to determine that after a tear down. If I pull the crank and connecting rods are there any issue reusing those bolts or are they a one time deal?

I am in no real hurry to get this back together and am hoping to really learn a lot more about all of it during the process.

Thanks!
Nick
 

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Hi Bear,

Thanks for all the gasket info. I am not EXACTLY sure where all it is leaking from yet. After looking last night (was labeling the different wiring in prep of the pull) I noticed it is leaking from the front of the oil pan and also the bottom of the front of the trans is wet with oil. Would that be the rear main?

Of course the valve covers and headers are leaking as well. How about replaceable parts while I am that deep in the engine? I guess I might have to determine that after a tear down. If I pull the crank and connecting rods are there any issue reusing those bolts or are they a one time deal?

I am in no real hurry to get this back together and am hoping to really learn a lot more about all of it during the process.

Thanks!
Nick
You do not want to reuse rod bolts. Once you break them loose, they are done with in my book. This will require a machine shop to remove and replace them with the better ARP rod bolts which most use. While they are apart, they should be checked for roundness & size. Often it is just a little more to go with new forged I-beam rods versus rebuilding the older cast rods if you have to have them resized and new rod bolts. Forged rods are of course stronger, so a little more insurance against a rod failure. The down side may be that you will have to balance the engine with the new rods, but a machine shop might be able to match the rod balance and then you would not have to balance the engine.

I would install threaded pipe plugs in place of the press fit cups in the oil passages. The pressed in plugs will work, just make sure they are "staked" so they don't come loose. Pipe plugs screw in and won't come loose, but a machine shop may be needed unless you have the taps to do so.

New oil pump and aftermarket hardened oil pump shaft.

I would install the 3/4 groove main bearings https://www.summitracing.com/parts/slp-113m/overview/make/pontiac
 

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Been there done that. Just be prepared financially. Once you crack it open that far. It wants to take the long road home. Lol
 

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Discussion Starter #6
Oh man. I was really hoping to not have to take it all to a machine shop. Was thinking maybe just the heads. I guess this is only necessary if I find some kind of failure or the rear main is leaking right? I was under the car tonight and I cant tell for sure yet if it is the rear main seal or just the oil pan leaking. The oil pan seems to be leaking in multiple points all the way around.

Thanks,
Nick
 

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Oh man. I was really hoping to not have to take it all to a machine shop. Was thinking maybe just the heads. I guess this is only necessary if I find some kind of failure or the rear main is leaking right? I was under the car tonight and I can't tell for sure yet if it is the rear main seal or just the oil pan leaking. The oil pan seems to be leaking in multiple points all the way around.

Thanks,
Nick
I believe mine was leaking thru the rear of the valley pan or distributor. when I pulled the motor it looked like it was running down the back side of the block.behind the flywheel. rear main could have been leaking also tho it was hard to tell. Had a worn cam and a lifter ticking which caused some slight scratching of the crank from cam/lifter shavings. So I decided to rebuild it and get the compression down slightly to run on pump gas. By the way. My car also ran good when I first got it so I put a new gasket set,oil and water pump. Detailed the motor and got ten years out of it.
 

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Been there done that. Just be prepared financially. Once you crack it open that far. It wants to take the long road home. Lol
X2 on above. If it's been twenty plus years I will bet you are leaking at main seal. But so do most Pontiacs. I would be ready to do a full rebuild if you start tearing it down . Then it's up to you how far and how many parts need or you want to replace . I will also add that I m willing to bet your into that motor for $2500/3000 if your able to do most work yourself,or double if you have a shop do it. I'm not trying to scare you from doing this but you really need to know up front what your heading for. Please read all you can on the threads on this forum and PY so you understand what you will need to do. Best luck Doug
 

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Discussion Starter #9
I have been reading a good deal on here about intakes as well. My current setup is a performer RPM and I have no complaints on it. I do still have the factory intake that I replaced ~20 years ago. Should I clean and put the factory one back on it or stick with the performer RPM?

It is hard for me to say if the intake helped or hurt since I originally replaced it while doing the cam.

Thanks,
Nick
 

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It's up to you, really. It's doubtful that the Performer intake makes any more power than the factory intake, in fact some tests have shown that it doesn't make quite as much. However it does save you some weight on the front of the car.

Bear
 

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Discussion Starter #11
Hi all,

Just wanted to update you guys. We got the engine pulled this last long weekend. We had to pull the passenger side header in order to get it to clear the A-Arm mount so I guess the headers will have to be reinstalled when the engine is back in the car (we know what a pain that is). We got it tore down to the short block and everything is looking great. The pistons and rods appear to be stock and a couple of pistons have some small dings in them (maybe from some prior build?) but overall everything looks great. I am going to get the heads checked out and start making a parts list of what is needed. I have a LOT of cleanup to do now. :)

Nick
 

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Discussion Starter #12
Help!

So another update. I have been doing a LOT of reading. My initial plan was to just clean this all up and throw it back in after getting the heads milled with a valve job and replacing "replaceable" parts like the water pump for example.

There is a noticeable ring line at the top of the stock bored cylinders that is enough to catch a fingernail on. From my understanding this is likely enough that it should be bored.

So here is my line of thinking that might be getting me down the rabbit hole. If I am going to bore it, I need to replace pistons and rods at the same time and all related components. Shouldn't I really go ahead and just get a 461 stroker kit instead of getting 30 over pistons with forged rods? My 2 biggest concerns are 1). what all outside of the stroker kit I am going to have to do that would be different than just going stock and 2). I'm afraid CR is going to kill me with my #62 iron heads.

I have been looking a bit at aluminum heads but man they are pricey. How much of my current head parts would be transferable, if any?

I am listing everything I know about this engine down below and I am likely going to have several follow up questions so THANK YOU very much in advance for all the expertise. I am not looking to make a race engine necessarily but I do love the power. It already felt pretty good in the power department and is not really a daily cruiser whatsoever. So if I can make a good deal more power for nearly the same money, that is my goal.


1970 GTO
- 1969 400 D149, #by distributor = 9790071, #on front just below pass. head = 0693249 YS
- #62 heads
- Comp 994-16 dual valve springs
- Screw in 7/16" studs
- Factory 1.5 rockers (I do have brand new Crane 28755-16 roller rockers that I intend to use)
- COMP Cams Magnum 292H Hyd Flat Tappet Camshaft Lift: .501" /.501" Duration: 292°/292°
- Comp 852-16 lifters
- Edelbrock Performer RPM intake
- Hooker Headers Competition 4901
- HEI distributor (have bought a D.U.I. distributor to install in this process)
- Taylor plug wires
- Quadrajet that I had just rebuilt following Clif's guidance
- It appears that the crank, rods, and pistons are factory.
- Probably forgetting something....

Nick
 

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Have customer going the 461 stoker route. He's not happy with the power of his 400 and it needs to be refreshed anyways. We went with a full Butler Package. It was a little over 2k for the 461 stroker package with flat tops. With his 87cc performer rpm heads he will end up with around 10:1. You can get custom dished pistons they can spec out for you to keep the compression at what ever you desire. For example I have another customer with a pontiac 350 were doing a butler 413 stoker kit on and we had to get custom domed pistons to bring him up to 10:1. Anyways beside the storker kit... obviously the block will need to go to the machine shop. An align hone (or align bore if it needs) deck the block a few thou to clean it up and .030 over on the cylinders. The machine shop will then need to check the clearance of the rods to skirt for the longer stroke. Also, new oil pump, pickup tube, and valley pan is a good idea. I would say a new timing set but you have a decent cam in it already so yours is probably new. Besides that, jet the carb up and let er rip.
 

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The bottom line is.......How Deep Is Your Wallet?

The Butler rotating assembly is the best bang for your buck - all new lower end parts and beefier.

Changes I would want is the 3/4 grooved main bearings if these can be substituted.

Add ARP main cap studs, but this may mean the block will have to be align honed in using them. Much stronger however.

You can use the iron #62 heads if you want, but keep compression around 9.0 ish for pump gas. Aluminum heads can go a point higher or so.

A.) You will have to order custom dished Ross pistons to drop compression with the #62 heads. But, you don't want to order anything until you have rebuilt the iron heads (if you use them) so you can get an actual cc number for the combustion chamber. This is needed to get the correct dish cc's to get you where you want on compression.
B.) If you use the 1.6 rockers, several things may need changing. First, stock Pontiac heads flow good to about .470" lift and then fall off. Aluminum heads will flow more right out of the box.
C.) Using 1.6 rockers will give you a valve lift of about .534". May not do a thing for you unless you do some porting/bowl work - but you can always try them.
* The springs you currently have may not work - not enough open pressure at maximum lift or not enough pressure could cause a valve to bounce on the seat.
* Next, you could experience valve spring bind. So everything needs to be carefully checked for clearances.
* You may need to use the RAIV valves which are longer than the stock valves so you can use a taller spring that will not bind at higher lifts.
* With 1.6 rockers you will want to slot the pushrod holes so the pushrod does not bind/bend against the intake side of the hole.
* Install bronze valve guides - no cheap knurling of the guides.
* Get a 3-angle valve job.
* Install a new heater hose nipple at this time.
* Some like to install a hardened seat in the head for the exhaust valves. I don't, but my opinion & choice on this one. Aluminum heads will have seat inserts.
* You could save money keeping your lift where it is and using those parts already known to work.
D.) An important and overlooked item is "squish" or "quench." Included a diagram. Squish is the area between the top of the piston and bottom of the head. It is that flat area adjacent to the combustion chamber and is positioned over the piston. You want to get this area to "squish" the air/fuel mixture into the combustion chamber to aid in preventing detonation and providing a better burn. Too large a space here allows the air/fuel mixture to have enough area to ignite as the flame travels across the combustion chamber and that's where you can get detonation.
* Best distance for that space between the top of the piston & head is generally .045" - which is also about the same thickness of a compressed Felpro head gasket. BUT, Pontiac pistons can be .010" to .020" below the deck down in the cylinder. So a .045" head gasket plus the distance the piston is down in the cylinder, let's use .020" like my engine, makes the total squish distance .065". Will it work? Sure, its what the factory used. HOWEVER, this was the day of leaded gasoline where the GTO's used premium and the higher octane had a lot of detonation qualities so it was not so much a concern. Ethanol blends and lower octanes can be problematic and you want to eliminate all the variables you can so you don't get engine destroying detonation or have to retard your timing and give up power.
* So why am I telling you this? If you order custom pistons, you can order them with the piston pin hole moved to give you a "zero" deck height. This puts the top of the piston even with the top of the block (deck) and then using the Felpro .045" compressed gasket, you have a perfect squish area. If using a stock pin location, the procedure would be to mill the deck .020" which will then have the tops of the pistons even with the deck and then you use the .045" head gasket. I am not a fan of milling the block UNLESS you need to - it needs to be cleaned up due to warpage or pitting, or squaring up the block for race purposes. Milling the block can change geometry on other parts like the intake side of the head, or intake, or pushrod lengths. Mill the heads and this is amplified to include fit problems with the valley pan.
* The option I have posted many times here is what I did. My pistons are .020" down in the bore. I used a Cometic .027" head gasket ($100 each) for a total squish area of .047" which should be good and will tighten up slightly when the engine heats up. So it is right were I want it.
* This is my suggestion/opinion and option, and should be discussed with your machinist. Once he knows where down in the cylinder the piston will be (piston height), he could change the piston pin location on the custom Ross pistons you are going to need to have dished.
*So before you order a custom dished piston, you want to know what the head chamber cc's are and the piston height IF you want to move the piston pin at all.
E.) As already mentioned, you will want to check clearances between the larger throw crank and the pan rail.
F.) Other stuff:
* aftermarket hardened oil pump rod if you haven't alread got one - that factory pump rod should not be trusted.
* 1972 and later baffled oil pan. Butler sells them inexpensively. He notes some holes may need to be slotted. Worse comes to worse, I would remove the baffle from the aftermarket pan and install it in your pan as long as your pan is good. You can buy a baffled pan on Ebay, but they seem to be pricey.
* get the rear pan oil reinforcements if you don't have these. Butler sells them. They require a little longer bolt and you may have to go to the local hardware store and get some grade 8 bolts and trim to fit.
* I like a double roller timing chain and gears.
* I am using the Butler blueprinted 60 psi pump. A little pricey. If you don't want to spend the money, get the Mellings 60 psi pump and add Tin Indian's Super Duty Oil Pump Plates Tin Indian Performance - New High Performance Pontiac Products I got this initially before Butler offered their pro oil pump in 60psi.
* see if you need the new stainless steel water pump plates and rubber inserts. Clearance the water pump impeller to plates as outlined here on the forum.

I think that should be good for starters. :thumbsup:
 

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Discussion Starter #15 (Edited)
Wow. A lot of great info. I am going to have to read back through that a few times to let it sink in. A couple of things initially.

I am looking at getting the edelbrock 61579-2 heads from butler along with the 4.155 461 butler rotating assembly. Also, the crane roller rockers I listed are 1.5 ratio.

Thanks again and I will be back with more.

Nick
 

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Discussion Starter #16 (Edited)
We tore the motor the rest of the way down tonight. I can at least say now that the rear main seal was not leaking. It was the two piece rope. Taking the block to the machine shop tomorrow.

As mentioned before, I plan to reuse my comp 292h cam and lifters. It appears to still be in great shape. It performed and sounded great in my 400.

Any opinions on reusing a hydraulic cam and also how will it perform in a 461 with those edelbrock heads?

Roller would be nice but wow are they pricey!

Nick

After doing a good bit of reading I believe it is fine to reuse the cam if it checks out OK. We kept track of the lifters when removing them but now I am terrified one got shifted at some point and I am going to get new ones...

Still interested in thoughts of how it is going to perform. Thanks!
 

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Discussion Starter #17
Ok, so just an update for anyone following along.

Decided to go with
- Butler 461 Stroker kit
- Edelbrock 87cc heads - 61575
- CompCam Xtreme XR288HR cam (recommended by Butler)
- The crane 1.5 roller rockers I have had for a while but never used
- Shooting for 10:1 compression (around .44 quench)

Just waiting for rotating assembly to come in so I can get rest of block work done.

Nick
 

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Discussion Starter #18
Cam bearing help, please!

Hi all,

I just got my block back from the machine shop and one thing has me concerned. It is the rear most cam bearing. All 4 of the other bearings I can shine a light and see the full circle. The rear most bearing LOOKS to be pushed in too far. I have tried to find a good pic of this rear bearing installed in a pontiac online but no luck so far. I am attaching a few pics (best I could get) in hopes one of the experts here can give me some advice. One of the pics is shining a light from the bottom of the engine and taking a picture through the crank side. From this angle it seems to have a small slither of light coming through from the hole in the bearing and also a bit of light coming through from in front of the bearing.

Thank you in advance....
 

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Hi all,

I just got my block back from the machine shop and one thing has me concerned. It is the rear most cam bearing. All 4 of the other bearings I can shine a light and see the full circle. The rear most bearing LOOKS to be pushed in too far. I have tried to find a good pic of this rear bearing installed in a pontiac online but no luck so far. I am attaching a few pics (best I could get) in hopes one of the experts here can give me some advice. One of the pics is shining a light from the bottom of the engine and taking a picture through the crank side. From this angle it seems to have a small slither of light coming through from the hole in the bearing and also a bit of light coming through from in front of the bearing.

Thank you in advance....
In the Pontiac rebuild book by Rocky Rotella, he has a photo of the cam bearing installed. With the engine block upside down, you should be able to look down the main cap saddle and see that the cam bearing oil hole is fully exposed/open to the cam journal. It should not be 1/2 closed or even partially closed. If you cannot see the entirety of the cam bearing hole, then it is not right, period. A little off set, in my opinion, would not be a big problem per say and may have been done to get the oil hole in its correct placement, but if any portion of the hole is closed off that would be my concern.

Machinist may have not gotten it 100% and he can easily take car of the alignment before any assembly.

Also make sure all the oiling holes for the lifters are free and clear. My 455 block was very crudded up and even though the block was hot tanked and pressure washed, I found a hardened chunk of sludge blocking one lifter oil supply hole - and you know this would have a caused a real problem to say the least once I fired it up.

Inspect all work after it comes back from the machinist. Clean the block real well. Use a lint free rag and WD-40 to wipe down all the inside of the cylinders until the rag comes up clean. The walls look shiny and clean, but you will be surprised at all the honing dust/material that is left behind in the metal's pores. :thumbsup:
 

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Discussion Starter #20
Thank you PontiacJim for responding. I am going to get them to fix the bearing and I will be sure to check/clean every hole I can find in the block before putting anything together.

Nick
 
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