[68grandprix]

I tore down my approximately 30,000 mile street 455 on St Pattys day, and I've got some pics/questions. First, I noticed the lifter valley has a ton of casting flash that I'll be grinding away. While looking in it, I noticed a small piece that looked loose. I reached down and gently snapped it off with my thumb and index finger! I wonder how long it would have been before that chunk busted off and fell into the engine? At one time I had a flat-tappet cam failure, which is one reason I chose to tear this engine down. The other is because I have a new car to put it in, and I think now is the time to step up to good rods and pistons. I'm glad I did, because that rod bearing doesn't look too great.
What's a good economical forged rod/piston combo? This is going in a street/strip '71 Lemans with a gutted interior. It'll run pump gas(91 is readily available). The cam is a Crower 041 copy with rhoads lifters that was swapped in after the flat tappet failure, and it's only got about 10,000 miles on it. I was planning on measuring the lobe lift to make sure the lobes haven't worn, as I found out the oil I was using for its high zinc content no longer had a high zinc content. If the cam checks out I'm going to run 1.65 roller rockers. If it doesn't, I might change cams.
The heads are 6X-4. I'm planning on installing stainless valves and porting them using tips from How to build Max Perf Pontiacs. What's up with the white ring around the valve in the pic? I'm sure I'll be posting more with questions about the build, but this post is long enough already. Jim

[steve25]

I would have that head checked for cracks as that clean exh valve and spark plug looks like they where steam cleaned.

[HWYSTR455]

Or that cyl was running lean. Maybe that intake wasn't going to full lift, or a vacuum leak. I don't see any coolant path from the head gasket impression, and would think if it were a head gasket the entire chamber would be clean.

Pieces of casting flash are a hazzard, and is why many choose to doctor the blocks. You can go too much though, keep that in mind. First thing I usually do after a initial cleaning is to use a small ball peen hammer, and go around knocking on all the flash. Anything that stays I hit with a wire wheel so no stress risers occur. Then I doctor oil returns. That's pretty much it.

Hyd cams, in my opinion, never reuse them. Why take the chance? And they're cheap, so the added insurance of a new one is a good idea.

Piston/Rod combo? Look at PPR. There are many out there now, and most are all in the general price range of each other.

Heads, yup, one piece stainless is the way to go. Full guides and seals, springs to match the cam. Ditch the splash shields, and open the pushrod holes.

Oh, that one rod bearing, it has copper showing at the parting line, I'd say the rods you have weren't prepp'd right. When you order your rods & pistons, check to see what a crank costs, might be cheaper than doing the machine work on yours. Align bore your block.

.

[68grandprix]

Thanks for the suggestions. I did look closely at both head gaskets, and didn't see any obvious damage to them. I will get a new cam, just looking at this one it looks like some of the lobes are more rounded, but it might be my imagination.

Hopefully my head isn't cracked. I do have the money to step up to aluminum heads right now, but I figure for how fast I want to run the 6Xs will work, and I really don't want to spend $2000 on heads.

When the rebuild was done, the crank was just polished, and nothing was done to the stock rods. I saw the copper and figured that meant something was wrong there. Another reason I'm going to new rods.

Right now the car is in need of some frontend parts at the very least, but I bought it for $150 and a Honda Odyssey, so it left me some room pocketbook-wise. I replaced the floorpans, and just ordered a radiator core support. It'd be interesting to fix just what needs fixing, and leave the car looking how it does, then stuff in the rebuilt 455. It might suprise some people

[77 TRASHCAN]

Your engine has many of the parts and Jim Hand's has. He uses the same cam, lifters, and heads, with an iron intake and Q-jet. Of course his parts are sooo highly massaged.

If you don't have Jim Hands book, I highly reccomend it. He uses essentially no exotic parts (except for the BBC rods and offset ground crank) salvage yard stuff. I've seen the car run. 11.50's are nothing to sneeze at. I've seen stripped down "Race" cars that don't run as good as his wagon...

I agree that a cam should never be re-used. Putting one back in the same block is the least risky scenerio for re-using a cam though( the lifter bores are all in same place, allowing the lifters to set back on the cam exactly where they were...)

Your cam doesn't look bad from what little I can see. remembering that the lifters rotate in their bores and are only are supposed to touch the cam on one edge. If the nose of the lobe is worn down completely across it, it's junk, if not, it might be re-used.
Make sure you use poly paste on the lifters and lobes just like the first time, when it was installed, and making sure the lifters rotate freely in theit bores......IF you re-use the cam...

Please do the body work. I saw a PERFECT car like yours at the Pontiac Oakland show in Tulsa a couple of years ago, had a blue interior, nice car...