350 to 454 swap...is it worth it?

[baclay9]

Bump
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[baclay9]

Wanted to update this and perhaps get a little more info. I tore into the motor to find out what all was there and found some interesting things.

First off this motor appears that it wasn't put together that long ago at all. It still says .060 on one of the main caps in sharpie.

Block is bored .060.

Heads- The peanut port heads have had valve work done to them and appear to have the same size valves in them the 781 casting heads I bought do. I am really thinking about running them again and just selling the 781's I bought. From info on here and what I have read the motor should be a torque monster with them. How many cc's should these peanut port heads be? They look to be the same as the 781's, 119cc.

Pistons- They are Speed Pro part # H581CP. From what I can find they are a .300 dome and should give me 10.2:1 compression with a 119cc cylinder.

Cam- Cam is Comp Cams XE268H. I already ordered a XE274 or I would probably just run this one again. The 274 shoould give me a little better rumble anyway.

Like I said, everything on the inside of this motor looks brand new. The cam lobes dont even have the black worn off yet. 0 wear on the lifter.

Thoughts, opinions???

[DaSchlange]

Put it back together and keep it. My motor was done in my new truck not too long ago, but I would keep the 454, it's well worth its weight in gold alone.

[ratty 46]

Are you sure your not reading the description of the "Strip Dominator"? They are generally used by drag racers & in the higher rpm range.

Ratty 46

[BigBlocksRule]

You'll have torque by default just due to the cubes. Where the 781's will shine is above 3 grand or so. They'll give you a lot more room to grow if you decide to hop it up more later. Stick with 'em.
Peanut and oval heads start with 2.06/1.72 valves, stock.

[baclay9]

@ 10.2:1 should I be ok on pump gas. Others have told me I will be borderline. I didn't think 10.2:1 was all that high of compression...

[BigBlocksRule]

10.2 is high for pump gas with iron heads unless you have a big, choppy cam or a computer to pull timing when you need it. You can have the shop unshroud the valves out to the gasket line and add "eyebrows" to the tops of the bores to help it breathe and bring your compression down a bit. I'd shoot for the high 9's, around 9.75 and even then it'll be iffy. If you ever take it to the coast, you'll ping like crazy due to the changes in barometric pressure. Most shops shoot for 9:1, so you're a bit on the high side. You can also have a bit of the domes milled off to help, too. As long as you're building a higher compression mill, you really should consider using those 781's you bought...

[baclay9]

Originally Posted by BigBlocksRule

You'll have torque by default just due to the cubes. Where the 781's will shine is above 3 grand or so. They'll give you a lot more room to grow if you decide to hop it up more later. Stick with 'em.
Peanut and oval heads start with 2.06/1.72 valves, stock.

Here is a question I would like your input on. When this motor was pulled out of my Dad's truck he took the harmonic balancer off of it and the flywheel and put them on his new crate motor. We didn't know that since this motor was balanced the balancer and FW should really stay with this motor. I called the builder in Ohio and he said I should be fine with just running different FW and balancer considering this motor will probably not see over 5500-6000 RPM. He said that it would be best to run the ones it was balanced with but I would probably never know the difference. What do you think about that.

Also, the crank appears to be double keyed on the front where the balancer goes. What would be the reason for that. One key sticks out like normal and then there is a keyway cut into the shaft 180 out from the other one.

[BigBlocksRule]

Have your dad take a look at the balancers he scavenged off of this engine. If it has the counterweight on it, it'll be for an externally balanced engine and any good replacement should work. I'd probably use a Pioneer, they're not expensive and are good quality. Same for the flexplate. Call the shop one more time and make sure they don't change weights on the balancer or flexplate, a good shop always makes mods to the crank and leaves the balancer and flexplate alone so they can be swapped without checking balance.
You should have 2 keyways on the same side, one for the balancer and one for the timing gear. If you have one on the other side, they're generally only used in blower applications where you really need to anchor the pulley.

[baclay9]

There is one on the other side. I guess someone was planning ahead...

I got up under his truck and looked at the balancer and it looks bone stock to me. I think I will be good.

Looks like at 124cc my compression would be 9.66:1. I wonder what they would charge to do that?

[BigBlocksRule]

Have the heads cc'd first, I've seen a lot of open chamber big blocks well over 119cc's!!!

[seth is usdm]

i'd be more than happy to take the 454 off your hands and send you my crate 350.

[baclay9]

Since this was bumped I will update it. I Went by the machine shop yesterday and they have my heads torn down. They magnafluxed them and they don't have any cracks. They are going to start on them Monday.

I am going to go ahead and order my pistons and rings. I am going with .210 dome speed pro's. Compression will be @ 9.5:1. Since I am tearing it down that far anyway I am going to go ahead and have it re-balanced while I am at it.
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[dmwphoto]

man I am jealous

[baclay9]

Hey guys, If my engine is bored .060. (4.310 bore) Does that mean I need to buy head gaskets that are 4.310 bore.

That is probably a dumb question and seems pretty obvious but I wanted to make sure the bore on the gaskets didn't need to be bigger or something. Thanks.

Also, what material should I go with? Should they be multi layer steel or copper or what?