TurboGibbs

iTrader: (6)

Yeah, 402, 396, 427 share the same 3.76 stroke so pin height is the same. Flat tops wont yield 10:1 I don't think unless you run some early closed chambered heads. Almost all big blocks had at least a small dome.

I'd just build it as a 454 and tell him it's a 427. He'll be much happier in the end.

viciousknid

iTrader: (8)

Thanks for the input.
The motor isn't gonna see high rpms so I don't think he's looking for huge power. That'll be in the supercharged 351 we are building for his '70 fastback

budhayes3

iTrader: (19)

If he wants huge power he can buy one of my dad's 572's for 16 grand...it's 3 grand more than the GM crate 572 but has something like 950 hp with a 1000cfm dominator bolted on top of it (Ceralli Competition Racing Engines, Paterson, NJ)

01GMC5.3

iTrader: (7)

if it were me I would check every thing out and bore it over and have a 468. it is a damn good motor for the money and power. and if you want to spend a bit more money balance the 454 rotating asc. for a even better on. IMO

viciousknid

iTrader: (8)

I'm not asking for ways to get more power from a 454 block. I'm asking about pistons for a 427.
Boss wants a 427 for his truck. He already has a truck with a built 454. He likes to try different stuff on different vehicles.

Been busy working on the '70 fast back so I haven't asked if he brought the 402 pistons in yet. I think he'll most likely need to run pop ups.

bennettracing

iTrader: (2)

I sell alot of muscle car parts for old Chevys a 6223 or 7115 crank is 396 402 and 427 all the rods are the same the only difference is the bore here is a web site with the pistons hope this helps http://www.flatlanderracing.com/trwchevy396_427.html

1Bear

iTrader: (1)

Your looking for pistons that will fit a bore of 4.250” + what ever overbore your going to finalize it with. A stroke of 3.760”, stock rod length of 6.135”, deck height of 9.780”, and a piston pin height of 1.765”.

There are a few choices out there in an out of the box type piston. To get a compression ratio close to what you’re looking for, you will find most of what is available listed a being for a closed chamber head, but is still what you’re going to be looking for if you want to come close to a 10.0:1 compression ratio with an 119cc open chamber head. They will still have a Dome, but it will be minimal for a big-block anyway at around + 30 to 35cc. Also, you can't depend on what Chevrolet advertises their heads at when it comes to specifications, you will have to physically measure them, but using published data will get you an idea of what your looking at.

Sealed Power has a forged piston (844-L2268F30) for a 0.030” overbore, that has a 35cc Dome, set up for stock pressed pins and will deliver 9.99:1 w/119cc heads. If you ran a closed chamber 106.9cc head, which I don’t recommend, they will deliver an advertised 11.25:1 compression ratio. They will set you back somewhere a little under $450 depending on where you get them.

JE has the 212133 piston available in the SRP line for a 0.030” overbore (4.280”), that has a 30cc Dome, set up for floating pins and will deliver around 9.5:1 w/119cc heads. They will set you back right at $600 for a set, so they are not cheap, but are nice.

I’m sure there are others available as well. I just took a quick peak to see what’s still listed as being available for the 427 cube big-blocks or 433ci in your case if you can clean it up with a 0.030” overbore, a 438ci if it needs to go 0.060”.

I understand what you said previously about what your boss wants, and that only a 427ci will do, but for anyone else out there, it really would make sense from a power and financial standpoint to just slip into a 489 to 496ci stroker kit. You could do the complete rotating assembly with an iron nodular crank, 4340 forged 6.385" H-Beam Rods w/ARP Cap-Screws, Forged Pistons, Molly Ring Set, Clevite Rod and Main Bearings, Digitally Balanced, and Blueprinted ready to assemble for about $1800. Adding a 4340 forged crank will run it up to about $2100. While you may be able to clean everything up and get by with a minimalist approach, not setting you back too much coin, if you have to rework too many items freshening it up, you could very quickly approach the cost of the stroker kit. Another nice thing about the kit is not having to worry too much about the compatibility of components such as what you’re going through now.

One last thing, the 454ci you’re basing your build off of is an externally balanced motor and just in case your not aware, you will need to pick up a neutral balanced flywheel/flexplate and balancer or your new motor will shake itself to death.

viciousknid

iTrader: (8)

Excellent info. I'm on my phone right now and will look into this more later. No plan to over bore. Stock bore and stroke for a 427 is all we need but I'll have to see what options are available and go from there. We figured since we have a 427 crank and 454 rods that we could easily pick up the pistons and get it ballanced but obviously wrong.
Thanks for the flywheel and ballancer suggestion. That could have been easily over looked.

Technically financially all we need at the moment is pistons. That has to be cheaper than a complete rotating assembly.

1Bear

iTrader: (1)

While a variety of pistons are still available for a 427ci big-block, you may find it a little difficult to find standard bore pieces. And like I was saying earlier, to meet your target for compression ratio you will most likely be looking a + 30 to 35cc Domed closed chamber piston, in conjunction with an open chamber 119cc head. The only reason I repeated that is because if anyone else goes back and decides to somehow duplicate part of your build, I would want them to realize that you can use a Domed closed chamber piston with an open chamber head, but not a Domed piston designed for an open chamber with a closed or semi-closed chamber head.

Even GM still has a forged 10.0:1 pressed pin piston available, but it is designed for their 110cc heads (same as the Edelbrock versions). The good thing is it is available in a standard bore size and have the standard 1/16” 1/16” 3/16” ring packs. They are used in their ZZ427/480 & Anniversary Edition 427 motors. Now if you could talk your boss into springing for a set of heads, you could basically duplicate GM’s package and have a pretty stout set-up with a reasonably small camshaft. The ZZ package is rated at 480hp/490ft-lbs.

viciousknid

iTrader: (8)

That's a lot of very good information. Thanks for sharing. This should help greatly. He alrady has heads but I don't know which ones. I'll go look up the numbers in a minute.