I am going .060 over on my 400, me and a buddy got a $10 bet on this and I know for sure that the folks on this board got the skinny on the true fact.

If I lose, I lose. I just want to know what cibic inch motor I will have if I bore my stock 400 .060". I still got stock stroke blah, blah, blah.

He says I will have a 404.80"

PS. What about a 302 .060 over?

PSS. How do you calculate this?

Thanks alot!
thatdude

 

I know there are many threads that cover this question, so I am sorry!
I wasnt quite sure how to search for what I was looking for.

Sorry again.

 

don't be sorry! i get 414.3" and 6.8L
http://raceabilene.com/kelly/hotrod/compression.html
i play with Chris Kelly's calculator all the time.

 

If you bore a 400 .060 over it will probably overheat and you wont be able to stop it.

 

CID = ((Piston Radius)^2 * Pi) * (Engine Stroke) * (Number of Cylinders)

CID = ((2.03)^2 * 3.14159) * 4.0 * 8

CID = 414.278

 

I agree with blackcell's math (assuming the piston radius with the overbore is 2.03 and stroke is 4, I don't know anything about the 400) which works out to be 6.7888 Liters (roughly 6.8)

 

I want to share what I learned in the last few days. According to my sources, the Ford 6.6L 400/V8 can only be bored to (.040) over maximum. The 400 cannot be bored to (.060) over.

Here is the information from my source:
The 351M/400 engines have "thin wall" castings and can not be safely over-bored beyond .040" -- Okay. Don't let this scare you away from "M" block engines. Ford did this to save weight. An "M" block engine is good for one or two complete rebuilds before you have to sleeve the block. All this means is that you can't over bore an "M" engine much beyond .040". As an example, when I had my engine rebuilt, the shop found that the #1 piston's wrist pin came loose and scored the block. A .030" over bore would not clean this cylinder up, so they had to put a sleeve in it. Big deal. It cost me $75.00 to fix it.



Formula to Calculate the CID (Cubic Inch Displacement) of an engine:
R² × Pi × H × number of cylinders = CID (Cubic Inch Displacement)

In other words;
Radius of the bore squared × 3.14 × Stroke × number of cylinders = CID

For Example:
If we have a V8 engine with a 4" bore and a 3" stroke, the formula would read: 2² × 3.14 × 3" × 8 = 301.44 CID

In other words;
2² (The radius of a 4" bore [2"] squared [multiplied by itself, or 2 × 2] × 3.14 (Pi = 3.14) × 3 (3" stroke) × 8 (The number of cylinders in this engine) = 301.44 CID

This engine, by the way, is the Ford 302! This formula will work with any engine.

For example, the Oldsmobile 350 V8, which has a bore of 4.057" and a stroke of 3.385" would be; 2.0285² × 3.14 × 3.385 x 8 = 349.88742333922 CID

A Ford 351 with a bore of 4" and a stroke of 3.5" would be; 2² × 3.14 × 3.5 × 8 = 351.68 CID

I hope this information is helpful to you. The information provided has been borrowed.

 

cartwright and indyjames500
I disagree. If what you say about thinwall casting is correct, then a 460 couldn't be bored .060 over. My machinist says that w/o concreting the block, .060 is very safe on a 400, and .080 is only slightly beginning to push it. With concreting, .080 is a snap, no problems. The only engines you cannot bore .060 over are mid to late model 302's, as they have extremely thin walls.

 

I agree. I had an extensive rebuild done on my 351M and the shop checked my block after .060 and said it was fine. I'm just waiting to get the restoration on the frame finished before dropping it in. I can't wait!

 

I've heard this topic hotly debated before. I have a 4-bolt Cleveland block that ran a little warm for whatever reason; it was/is .030 and is currently apart. It has some funny wear patterns on the walls, don't know why but I'd like to have it sonic checked someday (there isn't anywhere that does it where the engine currently is). I keep hearing that you shouldn't bore a Cleveland more than .030, and that is pushing it. On the other hand, I know an old man who raced Clevelands on dirt tracks all through the 70s and he said he bored every engine he had .060, and never had a failure from thin cylinders. All of the machinists I've talked to also haven't heard of the .030 thing, but most of them are probably used to Chevys. I've heard the 400s have a little more meat in the walls, but don't know for sure. Who knows?

 

I'm sorry I can't help you there. I borrowed that information and presume it to be acurate. Another thing, a comparison was made that should be checked. The 400 is a 335 series engine, the 460 is a 385 series engine. I don't think it's fair to compare one against the other.

Lifted78, is that the new MSD distributor, and where did you get those nice looking valve covers? I like the color choice, it's real sweet. I don't know what color I will use on mine. Thinking about painting it the same color as what I'm having my car painted, creme. Having car and engine compartment painted without drivetrain. Getting ready for car shows.

 

Originally posted By indyjames500
Another thing, a comparison was made that should be checked. The 400 is a 335 series engine, the 460 is a 385 series engine. I don't think it's fair to compare one against the other.

Of course you wouldn't. Nobody thinks it's fair to compare the two, when in all reality, they're more alike than most realize.

 

I was under the impression that all Ford V-8 engines since the 221 used the thinwall casting. That would be all Windsors, Clevelands, and 385's. Does FoMoCo say anything about safe overbores?

 

That picture looks really sweet, could youy give a list of the work on that engine?

 

What is safe, depends on a few factors. Core shift, proper cooling system maintenance prior to rebuild and intended application. For any high performanve application, I highly recommend sonic checking ($100-150) and partial fill using hard block.
http://www.hardblok.com/info.html

These have been done but I don't know if they lasted.
414/351C stroker (.062" over)
http://www.speedomotive.com/Jack's%20Stand.htm
434/400 stroker by Kenney Moore (.080" over)
http://www.bacomatic.org/~dw/km434/km434.htm