Cherokee SRT8 Forum banner

1 - 18 of 18 Posts

·
Member
Joined
·
3,325 Posts
Discussion Starter #1
Well I finally gave in and built an Iron 440 for a customer. Jim has wanted a 440 for a while and I am very much against building them due to the inherent flaws with crankshaft overlap, compression height, and rod/stroke ratio. Dont get me wrong, the 440 is a bad mutha, but it does give up longevity in doing so.

What we did was different than every other 440 that I have seen. I will not get into specifics, but it does involve a 1-off custom crank, 1-off custom rods, and 1-off custom pistons. If we are happy with the performance/longevity of the motor, we will begin offering these to everyone else.

Pistons and crank will be here by Friday and I will get some pics up then, but for now, here is the block that we finished today.

Step 1:


Step 2:


Step 3:
 

·
Just trying to go Fast
Joined
·
17,143 Posts
Woo Hoo!!! Jim's goin' big huh? Nice. Will it be in by the VA. race? I feel honored being the one who beat him the last time with his 6.1L. :lol: I know he's stoked!! This engine couldn't go to a nicer guy.
 

·
Member
Joined
·
3,325 Posts
Discussion Starter #3
Possibly will be in va. That depends on the parts coming in the week and balancing without issue.
 

·
Just trying to go Fast
Joined
·
17,143 Posts
Nice. Can't wait to see and hear it. He told me at Atco that was his last 6.1L race. Then he showed up in Orlando with the 6.1L, I had to give him flack.;) Glad to hear it's finally happening!! Have fun with the build!
 

·
Registered
Joined
·
8,340 Posts
Sweet! I hope its in va. Will be badazz.
 

·
Registered
Joined
·
673 Posts
What kind of longevity do these 440s have if you don't have the "1-off parts"?
Seriously. Good question....why couldn't the standard 440's be used as daily drivers?

How much is all this extra 1-off stuff to keep the engine so called reliable?
 

·
Member
Joined
·
3,325 Posts
Discussion Starter #12
The standard 440 can be used daily no problem. Just not as long as a 426 and a 426 wont last as long as a 392 and a 392 not as long as a 6.1
 

·
Member
Joined
·
3,325 Posts
Discussion Starter #14 (Edited)
Dmitry, I will send you an email.

Here are the custom pistons we made for this 440.

Please notice that we no longer use a generic round dish. By taking a mold of the combustion chamber, we can apply a dish that is a mirror image of the chamber. This forces all the fuel/air to the center of the combustion chamber where the spark plugs are for a more complete burn. Also, you can see that we now shave down the crown of the piston at the intake relief and exhaust relief in order to minimize the thin area that would normally be there due to the valve reliefs. We also have a longer skirt to give this piston more stability and increased strength which aids in the integrity of the motor. That last thing you want with a long stroke motor is a short skirt. The longer the skirt, the more stable it is.



 

·
Registered
Joined
·
1,249 Posts
The standard 440 can be used daily no problem. Just not as long as a 426 and a 426 wont last as long as a 392 and a 392 not as long as a 6.1

I agree but I think you need to share.....the 440 is a longer stroke than bore in the K1 configuration which creates side load on the cylinder wall. Most 426 are square engines (but in my opinion) the K1 rotating assembly has an offset issue no one talks about and of course the 392 is like the 6.1 with a larger bore than stroke.

I like what you are doing and assume you are using a "foreign" size journal?:)

.
 

·
Member
Joined
·
3,325 Posts
Discussion Starter #16
Current 440: 4.06" Bore x 4.25" Stroke
426: 4.08" Bore x 4.08" Stroke
392: 4.055" Bore x 3.795" Stroke
New 6.4L: 4.09" Bore x 3.72" Stroke
6.1: 4.055" Bore x 3.579" Stroke
5.7: 3.917" Bore x 3.579" Stroke

The 440 we are building has more bore and less stroke than the current 440 out there. Its not square like the 426, but its pretty close. It has more overlap, better rod/stroke ratio, more compression height, and a better ring pack with a better piston design. Those last 2 items are opinion, but the overlap, rod/stroke, and compression height advantage is a fact. The 426 is still a better motor for longevity, but I figured we would try to improve on the current 440 if we are going to offer it.
 

·
RIP Chuck G.
Joined
·
6,340 Posts
There's no replacement for displacement!! So these 440's are only possible with a sleved
block yes? Also could you boost it?
 

·
Member
Joined
·
3,325 Posts
Discussion Starter #18
These are not sleeved 440's. I am building a sleeved 440 but it has an even better ratio than the 426.
 
1 - 18 of 18 Posts
Top