Finally got around to tearing down the 455 I picked up a few years back that was supposedly a runner. If it was running, it definitely wasn't running well. Broken push rod and rocker arm bridge on one cylinder, couple cylinders with rust, etc. Came with a 2 barrel iron intake installed and I picked up a used Edelbrock performer intake and Thornton exhaust manifolds for it a couple years ago. "C" heads. Obviously it's due for a full rebuild and will be installed in my '75 Cutlass for general shenanigans and cruising purposes but I think I lean more towards the wild vs the mild build with the caveat of it looking relatively stock and driving well. Initially it will be hooked up to the stock TH350 but I could see that being upgraded in the future if/when that grenades.

So my questions are:

-first step wise, I guess I should tear it completely apart and take it to the machine shop to see what I'm working with block/crank wise?

-since the heads obviously look worse for wear, would aluminum heads be worth considering vs rebuilding?

-I have had lots of flat tappet cam failures with my AMC I6. Would a roller cam be worth looking at?

Any and all inputs/guidance are welcome and appreciated!

 

I'll ask the same question every one asks, what's your budget?

 

While not going crazy, I don't really have a set limit. I was expecting to spend at least $3k-$5k depending on what heads and what kind of cam were used. I could spend more if I could justify it to myself. And I like power so that wouldn't be hard 😆

 

Roller cam and GOOD lifters alone will run $1400.00 or so.
Speedmasteer heads can be purchased for $1200 or so a set. But you’ll need to replace the springs and do a little more work to them. That’s pretty much 3k total right there.
You may have to rethink your budget, or do without. That’s obviously your call.

 

I should have been more clear. $3k-$5k was my minimum rebuilding the iron heads and a flat tappet cam. I was saying I could justify more of it's worth it. Am I way off on that? It's been a while since I built a motor.

 

And honestly I'm surprised heads are that cheap. I paid $1500 for a bare head for my AMC I6!

 

You’ll have 7-8k in a good full roller build doing everything yourself except machine work.. It is what it is.

 

That's not beyond what I'm willing to spend if it's worth it. Not sure if it would be for my use case though which is part of what I'm asking. For the cam, I think maybe $500 vs $1400 is worth it to me to avoid potential flat tappet failures but is it actually that much of an issue for BBOs? It certainly is for jeep I6s (we don't have a roller cam option). I think I remember seeing posts from you a while back saying aluminum vs worked over iron heads weren't much different and maybe not worth the $ unless you were trying to eek out every last little bit of power and save weight. Do I remember that correctly and if so, do you still feel that way?

Regardless of parts recommendations and build direction, next step is tearing down the motor the rest of the way and taking it to the machine shop for at least a hot tank, magnaflux, and see what it'll take to clean up the cylinders then go from there, right?

 

Did you ever get it rebuilt? I'm in Bailey's Crossroads and I'm going through a 455 right now as well. I don't have a lot of money in the budget so I think I'm gonna go with my low compression block/factory intake and J heads. I got a set of headers for it as well, we'll see if I can make them work in my 71 Cutlass. Only non stock thing I'll do is a 2004R transmission. Right now I got the 350/350 combo in my Cutlass. I need to see what rear end I have it feels rather lively so I'm hoping it's a 3.42 or something similar

 

Good question, hopefully reality sets in quick. Your 2004R will need upgrades, even with a low compression 455, won't be cheap. You probably have factory 2 something gears, unless they were swapped. The good part is your factory rear end has common chevy 8.5" gears and posi with the superior bolt in axles. A 2004R and 3.42 is a great cruiser.

 

Funny this popped up when it did! I just got word the other day it's getting assembled right now (again). Aaron Shipley up in Baltimore is putting it together for me. Higher compression build, Eddy heads, mild roller cam. The core I took him turned out to have a cracked block which the machine shop didn't catch even though they supposedly magged it? Anyways, he had it all put back together and running on the stand when it started spraying coolant 🫤 He took care of me though. Found a new block and basically did the build over again. Hopefully I'll be able to grab it early in the new year.

 

Yeah I'm definitely gonna run mine on the engine stand in my backyard once I put the heads back on. Supposed to drop em off with my machinist this evening. He's in Falls Church. Hopefully next weekend I can start putting it all back together for a test run.

 

Who is your machinist in Falls Church? I'm still on the hunt for a good one somewhere local for my Jeep engine needs.

I'm also going to probably try to find the stock iron heads a good home since we went with the Eddy heads if you know anybody local looking.

 

I'm using a guy that does work on the side at his shop. This is the first time I've used him, but all he's doing right now is checking one head and replacing one valve guide. He's supposed to be finished by Tuesday, as long as the work is satisfactory I'll send you his info. Don't want to make a recommendation until I feel his work is solid.

 

The general concensus these days is roller cam. Many rebuilders wont use flat tappets because the rollers are more reliable to not fail. The rollers make more power. You'll make at least another 50hp with aluminum heads plus they're more knock and ping resistant than old iron heads. There are a lot of manifold choices and all of them work pretty well: Performer, Torker, Holley Street Dominator, Edelbrock O4B and Chinesium knock offs. You could build an iron motor but by the time you rebuild and port your C heads you will have spent the same as new aluminum.

 

But with rollers don't you have to use different valve covers?

 

Not necessarily. Sometimes you can get by with just modifying the baffles.

 

Really? Do I just cut the baffles out? I thought I saw somewhere I can use shorter keepers or something too

 

You prob read about the shorter poly locks, but there other options such as a spacer or thicker gaskets etc..

 

I am looking at a rocket racing valve cover spacer set right now to clear adjustable roller rockers. I am assuming I don't need much to use factory stamped covers. Would 3/8" be safe out should I go with their 3/4" spacer?

 

Wondering .. If you were to go with a pancake AC compressor off a G Body would you still get interference on the AC side?

 

You mean valve cover to compressor clearance? I hadn't even considered that being an issue. Hmmm...

 

I know this response is late, but the two machine shops I'd recommend in the DC metro area are Bill K's Advanced Automotive Machine in Waldorf, MD and Gunther's Machine in Walkersville, MD. I use Gunther's because it's much closer to me and I've been happy with their work.