Help with my broken 406

[Monster]

Dan/Ernie,

Thanks......... as you can see I'm a very senior member of CC and I've seen more than one thread take a detour. (In my warped/perverse way I enjoy some of the banter that goes on in these discussions as long as it doesn't get to personal). It's been said before "We're all here because we love our "hobby".............we just need to remember that hobbies are for enjoyment and not get personal when stating our views

As for this build, I too have built a number of engines over the years, this build was dictated because of a poor "rebuild"/failure ("rebuilt" engine was included with my basket of parts & partial built project car when I got it). I elected to take this opportunity to build out the engine to what I wanted as a dependable performance motor. Since most of my experiance has been in european performance and SBF's, I was not that framiliar with recomended mod's for the FE, which has been the source of most of my questions.

BTW: this afternoon will be breakin, I had a couple of issue to resolve: a broken collector/exhaust bracket & a missing (misplaced) piece to linkage

Thanks,
Mike

[farmallmta]

Hi, new member here. I don't have a Cobra yet, but I'm in the planning stages for one. I'm really into the FE engines, and have a fair amount of experience with them in pickups and full size Fords and Mercs.

My question about the 406 piston issue is: are rods available to connect 428 pistons in a 428 block to a 3.78" stroke crankshaft, thereby creating a late model FE 406. The 406 has some really good attributes pointed out in other member comments, including quick revs and peppy acceleration.

Are any rods available to solve the 4.13" cylinder bore with the 3.78" crankshaft throw?

[My427stang]

Farmall, none that I know off.

However, the 390, 427, 428 and 406 used the same rod length, so to build a real 406 you just need 406 pistons.

I am pretty sure Diamond sells the proper piston

[farmallmta]

Originally Posted by My427stang

Farmall, none that I know off.

However, the 390, 427, 428 and 406 used the same rod length, so to build a real 406 you just need 406 pistons.

I am pretty sure Diamond sells the proper piston

Thanks for the reply, Stang. From what I've been able to determine, Diamond carries 0.020 and 0.030" over pistons for the 406, but they're kind of pricey compared to some good deals I've seen on 428 pistons. It is my understanding that the pin is positioned differently in the 428 vs. the 406 due to the former's longer stroke of 3.98" compared to the 406's 3.78" stroke. Seems like rods would be cheaper and easier to have made than would custom pistons. Just a thought on the inexpensive side.

[Jamo]

TTT...all cleaned up.

[Excaliber]

Thanks Jamo, I appreciate your hard work for Club Cobra.

[olddog]

Originally Posted by farmallmta

Hi, new member here. I don't have a Cobra yet, but I'm in the planning stages for one. I'm really into the FE engines, and have a fair amount of experience with them in pickups and full size Fords and Mercs.

My question about the 406 piston issue is: are rods available to connect 428 pistons in a 428 block to a 3.78" stroke crankshaft, thereby creating a late model FE 406. The 406 has some really good attributes pointed out in other member comments, including quick revs and peppy acceleration.

Are any rods available to solve the 4.13" cylinder bore with the 3.78" crankshaft throw?

I think this was stated, but I'm not sure it was clear. The 406 and the 428 both have a 4.13 bore with the same deck height block and same length rods. Therefore to change strokes back and forth all you need to do is use the correct pistons for that stroke (406 pistons for 3.78 and 428 pistons for 3.98 stroke).

There were a few years that Ford did use a slightly different rod length and deck heights on some FE engines, but I didn't bother to check for specifics since I don't know that info. However anyone doing a build should be on the look out for these minor differences.

[Carnut427]

Originally Posted by olddog

...There were a few years that Ford did use a slightly different rod length and deck heights on some FE engines...However anyone doing a build should be on the look out for these minor differences.

The only engines with different length rods were the 352/360 (and possibly that odd Edsel engine). Deck heights veried a minor amount (on any engine), should always be checked and corrected to give proper quench.

Dan

[Excaliber]

But 'quench' was for the most part either not understood or simply ignored back in the day. I'm not sure about the other FE's but standard piston to block deck spec on a side oiler was about .030 below deck. If the specs are similiar for other FE's thats a LOT of clearance (and no quench, which is of course a worthy goal). Custom pistons would likely be required to move the piston up in the bore more toward zero deck.

[Carnut427]

Originally Posted by Excaliber

...I'm not sure about the other FE's but standard piston to block deck spec on a side oiler was about .030 below deck. If the specs are similiar for other FE's thats a LOT of clearance (and no quench, which is of course a worthy goal). Custom pistons would likely be required to move the piston up in the bore more toward zero deck.

Quench can also be corrected by milling the deck. This may require milling the intake side of the heads to correct the intake match, depending on how much is removed from the deck.

Dan