rebuilding my 455 again

[Fox80]

Yes the stock rod is press fit, I suppose you could bush a stock rod to take a floating pin. You could also turn the crank down to SBC rod journal diameter and use one of the million Chevy 6" rods available for a floating pin. Your machine shop is not balancing your rotating assembly if they don't have the pistons, you should also take your ring gear and balancer to them so they can insure it all zeros out when together. Piston choice depends on alot, did they deck the block, they should the casting shift on my 260 was really bad and from what I hear quite common on Olds stuff. If you want the compression up that high you or someone better actually calculate everything while assembling it to be sure it's not higher than you think. Play around with a comp. calculator, .020 thicker/thinner head gasket or 20cc larger/smaller head chamber can drastically change the comp. ratio, you need to know your final number for fuel selection

 

[Dennyboy]

Yes I will hand them everything so that it can be ballanced. The block is getting .030 over bored and decked. The crank has allready been done so I will stick with the press fits. Heads are 80 cc I measured my self with a home made checker that I made a while back. Im gunna go with the xe274 cam I got new springs and cleaned and swapped new all the parts on to my heads that had a valve job done over the winter. I still need to figure out head gaskets

Edit

Machine shop says I need piston with a 15cc dish. And head gaskets with around .050 compressed thickness.

 

[rccktmn2]

Have the machine shop sonic test the block and they will tell you how much you can bore it. The crank can be turned to SBC as mentioned and then you pretty much have an unlimited rod/piston combo you could go with as long as you don't get too crazy. Most 455s will go past the .060 safely but you need to have it sonic tested to make sure. Most early 455s will go 120 and still be in the safe limits of wall thickness etc.

 

[jones20992]

are you going to use a 460 rear seal?

 

[Fox80]

are you going to use a 460 rear seal?

Good point if your going to use the rubber seal you can have them do a slight polish on the crank while they spin it on the balancer.

 

[olds307 and 403]

The good pistons for a 455 are set up for floating pins. Pretty much leaves the heavy with old school thick rings, forged speed pro pistons. Why do you need .050" head gaskets? The pistons will be .025" in the hole. Get the Mr Gasket full gasket set, comes with rubber rear main seal and .038" head gaskets. Basically the old Corteco set with a rubber rear main and slightly thinner gaskets. The Edelbrock head gaskets are same in .042".

 

[Dennyboy]

I misunderstood them on the head gasket thickness. they said to stay under a .050 more around the .038 range will be just fine. I use the 460 rear main seal and offset the ends from were the cap meets the block. If I go with the floating pins I need different rods is what your saying correct? The cranks already been done and so ide rather not do anything else to it because I would have to spend more money and im guessing even if the sb chevy rods are cheaper. ide think after machining the crank again and buying the small block rods the price can't be much different and I would save some time.

 

[Dennyboy]

Well I pick the block up on Tuesday most likey. And I'm just gonna get the good eagle rods and Keith black pistons. Then I have to wait a another two weeks until I get payed to get the gaskets but I'll at least have the short block ready. Stupid money haha

 

[Fox80]

How are you picking up your block if you don't have the pistons yet? A quality bore/hone requires the piston set for each hole, usually when shops bore a block for an unknown piston they error on the side of caution and make them way to large

 

[High Roller]

Go with .060" CP Bullet series shelf pistons with the Eagle rods