'74 455 Rebuild

The Northwest is almost in a drought, and it's 70 degrees and sunny today, (southern Oregon), should be the same for the rest of the week. So it's time to start my project this weekend. (Now watch it turn cold, wet and freezing!) Some of you here know me as a long time lurker, and you know my car is a 1974 Tran Am with a 455 and TH400. And you know of my oil overfilling incident a couple of years ago. It's been running fine, (only about 600 miles since then), but I'm going to go through the engine, for peace of mind and to hop it up just a bit. It's only got 69k miles on it, so I'm hoping I can just get away with honing the cylinders and not having to bore it. I bought a set of '78 6X #4 heads and had them gone through. New valve guides, hardened seats, new guides, Chevy BB studs, new springs, retainers and clips. Got rid of the umbrellas on the springs, have regular seals instead. They're surfaced and ready to go. I didn't try to do any porting on them. My cam is a Competition Cams XE268H that has .477/.480 lift and 224/230 degree duration at .050 lift. Advertised duration is

268/280. I want to be sure to keep everything well oiled, so I bought a Melling HV blueprinted oil pump and a billet drive for it. I'll have the block tanked and magged, and the shop will press in my new cam bearings for me. I'll have the crank and rods and pistons checked. I have the new water and fuel pumps already, so hopefully rings, bearings and gaskets should just about do it. I replaced the timing chain about 10,000 miles ago, (almost 20 years!), so it should be okay. While the engine is out, I guess I'll have to have the tranny worked over too. This part I won't do myself. The last couple of times I've had my car out, the transmission didn't grab right away the first time I put it in drive, but started and shifted fine after I got going. I'm thinking about having an 1800-2100 stall conveter put in. I read that the cam I'm using is about as big as you can go and still use the stock converter, but the guy at the tranny shop said this converter is one step above stock and is what they use in 'vettes? I don't know how much of that is B.S. since I am not a transmission guy. He said $1,100 for the job, with about 300 of that being for the converter. Does that make any sense or sound reasonable? I bought some OEM paints for the engine compartment and frame, and I'll replace all of the hoses, vacuum lines, plug wires, and anything else that looks like it needs it. So basically, I'm just trying to freshen up the 'ol gal a little bit. Here's a link to a picture of my car, and I'll try to update my page with a few pics now and then, and keep you guys posted on how it's going? If you have any advice or suggestions, feel free to fire away. Just remember, I'm thin skinned, so try not to hurt my feelings! ;^)
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Reply to
HoDad
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First bit of advice, don't plan on everything fitting in to your budget. Every time you start something like this, you find something unexpected. Which is why I have a Jeep CJ-7 in my shop with the rear 2 feet of the frame removed and at a fab shop being replicated. Dropped the gas tank & aftermarket rear bumper to mount a reciver hitch to the inner frame rails. Found they were soft enough to put my fingers thru.

On the transmission, the standard rebuild kits for a TH400 here (minus gears & torque converter) will set you back about $475. The kits have gone up in the last few months. So the price doesn't sound bad as long as the shop doing it knows TH400's. Ask them to inspect any used parts they reuse.

On the rubber hoses, avoid autozone and the like. Your best bet for proper fit are restoration houses like year one. Your going to the expense to try and do her right, so go all the way. Less headaches down the road.

Another thing. I could be wrong, but I don't think 74 cars were HEI. If your isn't you could go with a under the cap conversion and have it astetically correct. Charles (not a pontiac expert by any means)

Reply to
Charles Bendig

In one aspect I'm really quite lucky. Not a speck of rust anywhere on my car. (I've owned it for 25 years, and it has been garaged for the last 22.) I do have the HEI ignition. It came out in mid '74, and my car came equipped with it. I buy most of my parts from Classic Industries. I think most of the resto houses use the same supplies. Thanks for the pointers. HD

Reply to
HoDad

I'm in the same boat you're in just that I'm at the finishing stages of a '74 Trans Am rebuild...

For bearings look into Federal Mogul 3/4 groove bearings. They offer excellent oiling. I believe they are available in standard and .010 under. If the crank needs to be cut down more due to scoring the half groove bearings will work good too. Don't install full groove on a 455. The crank is cross drilled from the factory and there is way too much load with the big azz main journals.

A trick on Pontiacs is to drill the bearings right over the oiling hole in the block so oil goes directly into the bearings. From the factory oil has to cross over where three drilled holes intersect in the block and then through the hole in the bearing.

Another trick is to drill a small hole in the oil gallery plug next to the distributor so it "pees" oil on the distributor gear. All 73-74 SD-455 engines came like this from the factory.

Make sure you don't loose the round roll pins that locate the timing cover. I've seen a lot of rebuilt engines where they get lost the timing cover is just bolted on and then the crank shaft dampener seal leaks.

Take pictures of all the clips and vacuum hoses before you take the engine apart. The TCS system on '74 is unique to that year. Be careful with the vacuum tree on the intake. its make of pot metal and will break if you slip with the wrench.

I hope you got the OEM Paints March '73-74 blue engine paint. Thats a very unique blue/gray and isn't available from Plastikote or Duplicolor.

Reply to
Dennis Smith

Thanks for the tips, Dennis. I will print them for future reference. I read the book 'How to Build Max-Performance Pontiac V-8's' by Jim Hand, and it sounds like the plug on the oil gallery you mention drilling is the plug you can see through the distributor hole. He says that some rebuilders forget to install that plug. I'll be sure to pay special attention to the plug and will consider drilling it as you suggest. I plan on taking a lot of pictures and notes during disassembly so it goes back together right. I'll make sure I have extra batteries for the digital! My engine paint is OEM Paints - Pontiac Blue 1973. From Classic Industries, part #62220. It's the one they listed for 1974, so I hope it's right. HD

Reply to
HoDad

If the paint is not right, any compitent auto body paint supply shop can match the orginal paint. With a spray gun you can paint everything, and have the correct look. Really the only paints that have to be "high heat" would be nu-cast for the exhaust manifolds. Charles

Reply to
Charles Bendig

I think you got the wrong paint. The one I went with is part #62230. Its listed as being for 73-74 in the Classic Catalog. Part #62220 is listed as a '73 color.

I have no idea why OEM Paints has listed 1971-72, 1973 and 1973-74 colors. Pontiac teal blue that was introduced on 1971 cars was used until March 15,

1973. After March 15, 1973 slate blue was used through the 1974 model year. There are only two colors used from 1971-1974. NOT three.

OEM Paints #62230 was a dead on match to the original paint I found on my friend's '74 T/A engine.

Reply to
Dennis Smith

Thanks Dennis. I just checked my Classic Industries book, and their web site, and they list the 1973 and the 1973-74 with the same part number, which is obviously wrong. I will give them a call and see what's up. May have to order the paint from a different house. HD

Reply to
HoDad

Just called CI, and sure enough, the web site is wrong. I am sending the paint back to them and they will send me the correct paint and reimburse me for shipping. HD

Reply to
HoDad

Dennis Smith wrote: any competant auto body supply shop should be able to match original paint.

I see a red door and I want to Paint It Black. ( Rolling Stones 1966 )

HF

91 Pontiac ( black )
Reply to
Harry Face

Hey 'Face, I didn't say that, Charles did.

Reply to
Dennis Smith

Oddly enough I listened to that song 4 times last night. Maybe it's a message from the harley gods. Charles

Reply to
Charles Bendig

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