CJG

Long story short, I got a rebuilt 455 and not really knowing anything about it I decided to tear it down before installing and found some things. First of all, it is supposed to be .030 over. It has a balanced crank, comp 280h cam with double roller timing set, hydraulic lifters, roller rockers and guide plates. Heads are J and supposedly have a 3 angle valve job and new stainless valves. That is basically all I've been told. One piston has a pretty deep valve scar on it and it appears the engine has been sitting awhile cuz the assembly lube is pretty dry and crusty. Not sure why when it was rebuilt they didn't put new Pistons in it and I don't think it happened since the rebuild cuz it does not appear to have been run at all.im assuming since it hasn't been run it makes no difference if the pushrods are put back in the same place, and I know I need to check for valve clearance with Pistons to figure out what head gaskets I need to put back in, and we plan to check the crank journals and all the bearings to be safe. I know it's a Risk, and not ideal to run it without knowing exactly what we have, especially the torker intake and holley 850 DP but we are way over our budget and really just have to try to go with what we have for now. We have a proform hei distributor, hooker competition headers and true dual exhaust. I know with the 280 cam we need to try to be around 10 to 1 compression and we are running a beefed up th350 trans with a 2800 stall converter. I know it's hard to offer up much advice but this is my sons first car and the 350/350 combo it had was tired and worn out and he is getting impatient cuz dad is taking too long and really not much experience doing this stuff. Any ideas or tips or advice is greatly appreciated.

Olds64

Sounds like a good engine. Why not just reassemble it, put it in the car and start it?

If one of the pistons has a valve strike on it you might want to double check the valve springs, rocker arms and pushrods for that cylinder. Other than that it should be straight forward.

TripDeuces

I would caution against 'assuming' anything. It seems you are already aware of that and plan to check everything so that is great.
I'm not a fan of a Torker and a DP Holley on the street but it is what it is. My only question there is do you have the hood clearance. I dual plane intake and a standard QJet would work fine for what you have but if moneys tight go with what you have.
Other than that it should be a straight forward swap.

oldcutlass

Well hopefully the work itself is not only a great way for you to gain experience but also for your son.

CJG

I DO have the E-brock 650 cfm carb off the 350, would it be better to use it instead of the holley?

oldcutlass

No, I think its too small.

CJG

Ok

TripDeuces

I think the 650 would be too small. It would work fine but is undersized for a 455.
It's not the size of the 850 it's that it's a double pumper which is more of a race oriented type carb. Some type of vacuum secondary carb would be more forgiving and easier to tune. Same goes for the single plane Torker. It will work fine but a dual planes is a better choice for a street oriented car.
This is not to say you couldn't get them to work fine. I drove a Torker on the street for years (with a vacuum secondary carb) and many here run double pumpers but I think you'd be better off keeping it simple from the start.

1970-W30

You say they didn't put new pistons in it when it was rebuilt, If it's bored .030 over then it does have new pistons in it. If valve has contacted a piston top, to the point that it has a " pretty deep scar" You'd better do some close investigation on the valve train and the valve that made contact.......

CJG

That's just it. The whole thing is strange. It has the piston in it that has the valve strike, but after taking everything apart you can tell by looking that the valves are all brand new and the cam as well. The engine is all fresh machined and there has been no oil ran through it. Very strange.

CJG

Ok, now, tips on getting the dowels out of the block?

TripDeuces

Slide hammer with a drill chuck type head on it.
Vice grips and finesse it out with light hammer taps.

redoldsman

It sounds like you need to pull the timing cover and check the cam timing. That could cause the problem with the valve hitting the piston although it would probably happen with more than one.

CJG

We have the whole motor pretty much disassembled. Going to take all apart, inspect, re lube everything and put it back together so we know everything is correct.