Standard 400 gm Block

[bburman]

Has any one out there sucsessfully used a standard 400 gm block & made 900 hp what have you done to the block .I want to use this block as it was my late brothers with an F2 Procharger.

[Michael]

Welcome to the forum.

900hp is a lofty figure, regardless of which block you're using. I would highly suggest contacting a builder with experience building engines that produce numbers in the range you want to achieve. SMRE (click the banner at the top of this forum) is a good place to start. They are also a ProCharger dealer, so if you tell them you want to build this engine using an F2, they will be able to steer you in the right direction.

The first question to be asked is how do you plan to use this engine? Is it going in a street car or a dedicated race car? If it's a street car, how high do you plan to limit the revs? If it's going in a race car, what kind of racing and/or class will you be running (drag, road race, etc...)? Knowing these will help to set some limits as to what you'll need and what you can do without (ie. titanium con rods might be overkill on the street, but may be necessary for a particular racing class).

Second question would be whether you plan to increase the engine's displacement, either by stroking or increasing the cylinder bore? At times, when you start moving away from standard-sized parts (like crank stroke, main bearing or piston diameter) the choice in high-performance parts becomes a bit limited.

The fact that you've set yourself a horsepower target is a good start. Next will be to answer the above questions and from there, set a budget. Anything is possible if you throw enough money at it... it's just a case of making sure you don't end up throwing good money after bad.

[bburman]

Hi Micheal,
I have worked out all the internals required for this aplacation after talking to four engine biulders (smre is one) and the all tell me it is risky to use a standard gm block that is why I have posted this to see if anyone has sucsefully used a standard 400 gm block & made 900 hp and what things they have done other than 4 bolt mains & studs.

[Michael]

I didn't realize you had already done the background work. That's good to hear.

Most standard GM blocks become a bit questionable when horsepower numbers start to climb over 500bhp. There are exceptions of course, blocks like the "rocket block", but those are few and far between. Obviously, that explains why people opt for race-prepped or aftermarket blocks when it comes to making big numbers, so I'm not surprised at what these shops have said.

I think the only thing I would suggest would be to get the block inspected (ie. Magnaflux, sonic inspection, etc...) to check the overall integrity. Cylinder wall and deck thickness are probably the biggest concerns on a block like that. If everything checks out OK, I can't see there being a big problem producing the numbers you want to see, especially if you've already put together the list of internals specifically FOR the application/horsepower output you want.

The way I look at it, if Callaway could produce 900bhp in their twin-turbocharged Corvette Sledgehammer using what they claim was a standard GM 4-bolt "truck" small block (355cid), I can't see why you couldn't do the same with a 400 block that has the necessary integrity to sustain the power and boost.