blaker1

I have recently received my 403ci olds from getting bored .20 over with new pistons, rings, cam bearings, frost plugs and all new mains. I have a set of 72' 64cc heads going on it and all these new parts
-oil pump
-gasket kit
-water pump
-alt
-dist post
-cap+ rotor
-plugs wires
and much more chrome etc, does anyone have any tips for assembly? ive been given the standard assembly lube for the mains and given ideas on break in oil. was jus wondering if theres any things that are 100% I have to do on an olds motor (originally a chev guy) any of your guys tips thoughts an suggestions would be very much appreciated as well have a complete 330ci outside with all parts anything I should swap?

M-14

You'll have to enlarge the head bolt holes on those 350 heads, drill them out to 1/2".
Make sure you have a repair manual, the firing order is the same as a sbc but the rotor turns in the opposite direction.

brownbomber77

Well... 17/32..not just 1/2. Not trying to be critical,,but ARP head bolts don't fit inside just a 1/2 because the enlargement under the head.

1970-W30

Also the locating dowels on the block (2 per head) do not match both the holes in the 350 head, one dowel hole in each head will need to be drilled out a bit to match the block dowel size. Brownbomber is right, 17/32 is the perfect size for ARP bolts which I highly recommend. Also your heads are probably closer to 67 or 68cc as my #5 heads were. Just something to consider when you're trying to determine a rough calculation of the desired compression ratio. I would also use the Cloyes true roller timing chain set and degree the cam for sure.

Octania

First off, let's hope your block was bored twenty THOUSANDTHS over [0.020"] and not 0.200" [two hundred thousandths] oversize. That might have the pistons rubbing each other. (Math experts claim the exact location of the decimal point matters...)

You can use the 330 crank in the 403 if you have the assembly balanced, and use the 330 flexplate. Forged crank is extra insurance. I needed a crank kit on my similar 403 build and used the 330 crank instead.

Be sure the aft end of the LH oil passage gets the plug WITH A HOLE IN IT to lube the distributor gear. Common error of the typical generic engine builder- hey the freeze plug kit came with new plugs, and new MUST BE better than old, so let's use them instead!.... wrong. Factory correct old used is better than new in many cases, and this is one of them.

Make sure the heads are machined to allow the valve lift your cam provides. Not usually a problem with mild builds. Good time to machine for teflon seals if you prefer that type over the umbrellas. Stock rockers? If so get new ones- well worth the rather small cost.

What's a distributor post?
Using an HEI I presume?
O-ring on distributor housing, NO FLAT GASKET. Test fit w/o o-ring and make sure there is some shaft end play when dist'r housing is down against the block. Unlikely to be a problem, unless some Chivy mechanic tried to shim the gap away, which is not good. Olds pushes the dist'r drive gear DOWN, against a seat machined into the block.

Do a trial assembly first, to make sure everything fits right before applying final assembly sealants.

You can use factory head bolts [I did], and you will *have to* in the one boltstud location unless you are not using those brackets. Remember that the 403's larger head bolts are torqued to 130 ft-lbs [coated with engine oil], not 80 like a 350 CID. If you go with ARP fasteners, use their recommended lube and torque values as ARP so carefully engineered.

Degree your cam in. Even if all that does is verify the correct timing marks were used, and that your damper's timing mark is correctly representing TDC.

tomngary

@ Octania

this is an interestion post as I am in the middle of the
exact same build.

you posted.... "Be sure the aft end of the LH oil passage gets the plug WITH A HOLE IN IT to lube the distributor gear. Common error of the typical generic engine builder- hey the freeze plug kit came with new plugs, and new MUST BE better than old, so let's use them instead!.... wrong. Factory correct old used is better than new in many cases, and this is one of them."

Can you possibly go into a little further detail on this? I have gotten my block back from the builder and I noticed a "new pipe fitting type plug" on the side of the block. Is this the plug you refer to? Can I take it out to check it for the "hole" if this is the plug your talking about?

Also, Can I place the heads on the block WITHOUT the gaskets to check for alignment and such? or is this not a good idea to put these bare surfaces together?

Thanks,
Gary

coppercutlass

gary that plug that he is talking about you can usually only see when you have the plug off behind the rear cam bearing the big one . Unless you can see it with a flash light and mirror., pulling the plug off might be cheap insurance. A dry fit wont hurt anything but when you factor in the head gasket thickness and intake gasket thickness it will all change specially when torqued .

tomngary

Ok, this really has me worried, I had a speed shop redo my block, cleaned and all new bearings. But the shop is not big on oldsmobiles I dont think. So now im not sure what to do. This is my first build and im still learning my way around the oldsmobile details. Would i have a failure if the the wrong plug was put in? The block is still in short block form with the crank installed (no top end or oil pan on). Can i see this plug from the crank side? Can u point me to any photos on what to look for?

Thanks for the help,
gary

coppercutlass

Not neccisarily engine failure but your dist. Gear will eventually grind down to nothing. If no one else hs pics I have a block at home I can take a picture off and post up later tonight.

tomngary

@coppercutlass,
that would be awesome if you could do
That, i would be very greatful !

Gary

tomngary

I FOUND IT! The distributor side oil galley plug I mean.
Hopefully it's the right one.
I have the distributor out and stuck
an inspection mirror just inside the
distributor hole and found the plug with
the small hole in the center of it.

Is that the right one?
If so, thanks for the lesson, as I had no
idea it was even there!

Gary

coppercutlass

coppercutlass

Sorry for the late reply I just got back in from the garage.

cutlassefi

Hmmm... what drives the oil pump? The distributor. Yes it'll quit running but you'll still have more junk in the bottom of the pan.

Tomngary- Glad you found that it was fine.

coppercutlass

I have heard people say the filter will catch that before anything bad happens. Not saying it is ok to run with out it. Specially if he has the engine out double checking is the way to go .

Octania

Not sure what I am looking at there exactly. I think it is a view of the aft face of the block, with the 5/8" or so diameter soft plug out and the oil passage plug visible in the aft end of the LH oil passage.

In my experience, all the SQUARE DRIVE plugs as seen here have the hole- though the passage could still be plugged with gunk behind that holey plug [Seff story].... During a block cleaning that plug should be removed. If the plug is a HEX recess, then it is often hole-free, but I have seen hex drive plugs with the hole.

I went looking for my photo of the Holey Plug taken with inspection mirror and flashlight, but Photobucket is absurdly slow and therefore useless.

coppercutlass

That's it octania the aft end plug sorry for the no description lol.

tomngary

from the photo, I'm thinking the plug I found was NOT the right one I
needed to check for.
The one I found was a hex plug with a hole in it inside the distributor
shaft hole on the piston side of the block facing the the distributor gear.

Is this the right plug or should I keep looking?

Gary

coppercutlass

If you are looking at the rear of the block. This plug is to the left of the big plug. You have to have the distributor out to see it. It is directly in front of where the dist. gear sits.