Which block to use: 428CJ or 427 center-oiler

[4twennyAint]

OK, Barry hasn't returned my call yet, and I just want to get some input on this.  I want 550hp. I would use a 4.25 stroker kit and all new aluminum heads and goodies up top.  I have two blocks: a 428CJ and 427 (C4AE-6015-A) center oiler.  Both are standard bore and in good condition.  Which one should I use?? 

[afret]

The center oiler doesn't have the lifter oiler passages drilled so you can't run a hydraulic or hydraulic roller as is.  You won't be able to get pressurized oil to the lifters if you want to run solid rollers on the street and won't be able to use the T+D race rockers.   You might look into getting the oiling passages drilled and use the 427 block. 

The CJ block would be OK but at the power level you want, it's probably a good idea to get the main caps cross bolted.  You can get Pro Gram caps and get them installed.  At the minimum, I would get #2 and #4 main caps cross bolted.

[jayb]

At 550 HP, the easy call is the 428 block.  I'd respectfully disagree with Earl on the crossbolting thing.  Crossbolting is always a good idea on any high performance FE, but in my opinion you can get away without it up to the 600 HP level.  That may not be true if you are going to be dumping the clutch with slicks on the car, which is hard all along the drivetrain, but if you are running primarily on the street, or with an automatic (and no trans brake) at the track, I think you can just stick with the two bolt mains.

You should end up with around 460 cubes with the stroker kit and 428 block.  I got 550 HP out of my 390 stroker with a Comp 306S solid flat tappet cam, Victor intake, 850 carb, and a good street/strip porting job on the Edelbrock heads.  You should be able to do 550 HP pretty easy with another 20 cubes, and you could go with a shorter duration cam to get there.

The problem for me has always been that once I get to 550, I like it and want 600   If you think that might happen to you, start with the 427 block, and if you can find someone to drill the lifter oiling passages, then you have unlimited options for valvetrain components.  Not to mention another twenty cubes...

There are lots of paths you could take with those two blocks; good luck on the project.

[afret]

Yup, you're right, probably not necessary but good insurance for when you decide to step up the power as usually happens. 

[My427stang]

Unless you want to run hydraulics, I'd go center oiler

For about the same price, you get 25 cubes and the power that goes along with it

[4twennyAint]

You guys are awesome, thank you all for the input.  A few more questions:

1. With a 427 CO, does anyone have any concerns about main and rod bearing longevity, considering the increased bearing loads imparted by 550 HP, longer stroke and 6200 rpm bursts?

2. Other than no pressure to the lifter bore, is there a difference in the oiling circuit on a 427 CO versus a 428 CJ (does the 427 CO have a completely unique oil circuit)? 

3. With a solid, flat tappet cam, are there still concerns about lobe/wear failures?

4.Any recommendation for rocker asy if we don't oil-drill the 427 CO block (and use a flat tappet solid?

Thanks again!

[jayb]

1.  No concerns about bearing longevity in my opinion.  That will be affected much more by the quantity of oil in the engine, the oil pan, oil pump, recommended mods to the oiling system, restrictors and/or oil return tins, etc.
2.  I'm not sure if the 427 CO has the oil pressure relief valve in the back of the block, but other than that the oiling systems of the two engines are the same, as far as I know.
3.  There are always concerns about flat tappet lobe failures these days.  Buy your parts from a quality, FE oriented vendor and run a zinc additive in the oil to minimize risk.
4.  It's too bad the Erson rocker setups are no longer available, because they were a great setup.  On my engine, though, I just ran the stock adjustable valvetrain with rocker shaft end stands from Precision Oil Pumps and that work fine with the 306S.  The whole Precision Oil Pumps rocker system is good also.  I have run the Comp Cams rockers with the Precision Oil Pumps shafts and stands with good results.  And a lot of folks have had good luck with Harlan Sharp rockers.  Lots of choices out there...

[My427stang]

You guys are awesome, thank you all for the input.  A few more questions:

1. With a 427 CO, does anyone have any concerns about main and rod bearing longevity, considering the increased bearing loads imparted by 550 HP, longer stroke and 6200 rpm bursts?

Mine has been together since 2006, the toughest thing you need to do is to find the proper main thrust bearing, its a little smaller than later blocks and depends on the year of your block.  Either that or machine the block, or turn down a cheaper thrust bearing to fit the block.  After that, the design is the same as any other FE except with more stable mains

2. Other than no pressure to the lifter bore, is there a difference in the oiling circuit on a 427 CO versus a 428 CJ (does the 427 CO have a completely unique oil circuit)? 

Its the same as any 390/428, except it has a relief valve on the back of the block and no oil to the lifter galley

3. With a solid, flat tappet cam, are there still concerns about lobe/wear failures?

You need the right oil, no binding, the right springs, and good assembly.  I haven't had any issues in any engine, but if you are concerned, and want to go hyd roller that would be a significant nod to the 428 block

4.Any recommendation for rocker asy if we don't oil-drill the 427 CO block (and use a flat tappet solid?

I love the old Ersons but they aren't available, I am pretty sure the street T&Ds dont require pushrod oiling, have to defer to the guys that have used them.  That being said, Precision Oil Pumps, Harland Sharps, pretty much any name brand is going to be just fine.

[DEANs427]

the 27 has a in-block oil pressure bypass and thick cylinder walls. any time you go stroker you need to consider the added stress on the thrust side of the cylinder. do your home work on "rod ratio". CRUSIN' THRU THE CAR SHOW WITH THE SOLID LIFTERS CLATTERING A BIT GETS THE CHEVY BOYS NERVOUS....
had a lot of guys look under the motor and say, "yeah, its a real 427, the bolts are there"
BTW, your 27 block only has 2 motor mount bolt holes on each side

[JamesonRacing]

Don't forget about the motor mounts...the 427 block probably only has a two bolt mount, so it would be more difficult to install in a Mustang or Fairlane.  Certainly not impossible, just another consideration.

[My427stang]

True statement on the mounts, no issue on a Mustang, you drill one hole in the factory mount.  I have not used one in a Fairlane, so not sure how it affects them.