1) What is the absolute BIGGEST ford smallblock engine that can be built?
(Based on the 255 through 351W block series)

2) What is the very biggest FORD gasoline engine that can be built AT ALL?

NO LIMIT to modifications. The object is pure cubic inches and racing horsepower.

What is the absolute max as of right now.

 

Ford has the A600 block which with the 520 crank should yield right at 600 CI.

Depending on when and where the small block was made and how comfortable you are with such little space between cylinders, you can get just over 400 CI out of them. Cylinder walls get thin at some point and reduce longevity.

 

The biggest for the 351W series is 460 cubic inches using an aftermarket block.
Bore: 4.155"
Stroke: 4.250"

For a factory block you can do 427 cubic inches.

I don't know on the 460 blocks.

 

People - we have a problem.

CHEVVY has potential smallblock builds up into the 520+ inch range...

We ought to find some way to get beyond them. As it stands, we're lacking cubes.

I don't like it, but I'm hearing as large as 550 in a smallblock.

What can we do?

 

409 is the largest you can safely and reliably run on a small block chevy. At least on the second gen (such as the LTx) I think it is. Cubes don't count unless they are contained, but if you must have thin cylinder walls and big displacement, pick up a 351M or C, I think they have more distance between the cylinder centers.

I chevy has two small blocks, the normal 350 that is well known and then the 400. The 400 is sought after because it makes bigger/better strokers.

 

We need to explore this deeper, because later track racing engines have gotten big.

And you don't want a heavy block - it costs. The handling becomes front end heavy.

Go with a Cleve, and you go with the weight. Ditto 460 builds...

We need to spy out just how big chevvy smallblocks go - because that's the meat of the issue.

If CSB's are getting bigger than we can go, we need to find ways to get past where we are now.

In simple words: Do you find the idea of - "BUILT TOUGH, WITH CHEVY STUFF" hatefull?

 

Like I said, The Biggest SB Chevy engine I know of is a supercharged 409 LT1. I know of several 396 and a bunch of 383s. Of all of those the reason there are more 383s are they are more reliable. Of course I only delt with 94-6 Impala SS and that experience was only 10 years.

Your welcome to believe everything you read on the internet, but this one I wouldn't.

 

So - how big and bad can we go?

In your opinion....

The quotes of size I put out came from a modern day dirt track super stocker who is prepping a car to run RIGHT NOW.

That is what is in his ride....

It's likely 450 more than 550 - but even so....

How big can we git?

I don't want to be the stupid basstard who did not spot the build possibilities....

 

I'd use only production parts that are easily replaced.

Scat has a crank with 4" stroke used with 4.030". I see right at 400 being the normal limit. so if you find a little bigger like their 4.10" crank and possibly more oversized pistons, you might be able to safely squeak out 410. However, I'd want to look at the blue prints and figure out how thin of a cylinder wall you could go with out compromising the block. Displacement isn't the only place power can be made. The proper heads and cam to match your desired operating RPM range would be crucial.

Edited, now if you want to dump money into custom rotating assemblies and modifying the block you could go to 450 on a limited constant go engine. However a motor that you must start up every day or even just on the weekends wouldn't be a good choice for that kind of work. Taking off and burst of acceleration would be very hard on it.

 

A tall deck 351w block can be taken to 427cid. A 351c, with some work and custom rods, can be taken to 400cid, but reliability would be an issue due to the thin bores.
Windsor, Cleveland, and M block are all the same bore spacing.
For max power, I'd start with a 428 block, stroke it out to a 468, aluminum heads, 9.5:1 compression, custom long tube intake, thickwall stainless tubular manifolds dumping into a pair of decently large turbos, and a very thorough balance job, with lightweight flywheel. Should be good for around 800hp and a hair over 700ft/lbs if Desktop Dyno is halfway reliable.

 

since we are talking weight as an issue, and reliability, and for racing purposes, what about boring/stroking an aluminum 460? with alum heads and intake, forged pistons, rods, crank and cam, can't weigh much more than a stock cast iron 351C w/ cast internals

 

Since no one has addressed it yet, the very BIGGEST Ford gas engines that I've ever known of are the 820 cube Kaase Ford "Hemis" that the Pro Stock guys use.

Those 500+ cube SBC's...all require $$$ aftermarket blocks and cranks. Never really understood that anyway. If you want that many cubes, why not run a big block?

 

Connect two motors(351) crank to crank and have 702 ci!! Bigger Is not always
better. If you can have a motor say a 351 turning 10,000 rpm and get up there
quickly it will perform better then a bow tie mountain motor tweaked out, at least
for the drag strip!! For a given final drive ratio the only way to go faster is by increasing the rpms!! All the HP and torque won't get you any faster, maybe take
off faster but if you run out of power and rpms what does that matter?