4BT stroker

clarkoh said:
Is there a sticky with piston dimensions? In my case, I need the distance from the top of the piston to the ring land. Plus the usual bowl volume, compression height, etc.
Ordered a 3/4" thick piece of ductile iron plate and a set of 0.200" long Cunningham rods. Have to get one of my blocks bored and cleaned. I have a line on a surfacing machine with capacity to do blocks, heads and deck plates. I can use it, but might buy it.
Thanks for the help. The forum has been invaluable.

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[ame="http://s358.photobucket.com/user/westonmerril/library/Piston%20Info?sort=6&page=1"]Piston Info Photos by westonmerril | Photobucket[/ame]
 
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Ran into a glitch. The rod journals on the 4.5 crank are smaller and narrower by several thousandths. The 3.9 rod would not fit onto the 4.5 crank. Its not a huge deal, since Cunningham is making me new rods. Just need to get the correct rod bearings. I found QsB4.5-30 parts manual on eBay. Should be all I need to sort this out. Fortunately, the mains are exactly the same. 12 week lead on the rods. Again no big deal, the truck is not ready for an engine yet.
I have a p7100 pump from 3.9. Any suggestions on who can freshen them and improve on their performance. Thanks again for the help and support.

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With use of the deck plate, obviously I will be using studs. Does ARP make a longer stud? Of are the "stock" length studs long enough to use with the plate? I could spot face the head in the bolt holes. Would that be safe?

Would putting a fire ring on both sides of the deck plate be advisable? Should a receiver groove be used on the block and head? Is copper a good choice for the gasket?

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ARP will make you whatever you want. Probably not cheap, but they'll do it. They also have a lot of stuff in stock and will put together a custom bolt set for you, if they have the right stuff on the shelf.

Piano wire is common for reciever groove setups. We have a large deck plate on our DT466...I am wanting to say it's grooved on both sides, but it has been a while since it has been off. We are using NO head gasket, IIRC, just o-rings.
 
I need the head gasket for clearance. I have used copper with wire on gas engines. W a receiver groove. And silicon on about everything else.

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clarkoh said:
With use of the deck plate, obviously I will be using studs. Does ARP make a longer stud? Of are the "stock" length studs long enough to use with the plate? I could spot face the head in the bolt holes. Would that be safe?

Would putting a fire ring on both sides of the deck plate be advisable? Should a receiver groove be used on the block and head? Is copper a good choice for the gasket?

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I wouldn't spot face, get longer studs.

I would cut a o-ring groove in the block and the head. I don't think for what you're doing a fire ring is the best idea.

I'd run stock cummins gaskets. With a o-ring it should handle all you want to do. I personally hate copper. Leaky bastards.
 
Yeah but when they blow, they have that cool green flame!

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And yet another question. Since I will need longer push rods, does anyone know a source of unassembled push rods? I have made my own many times, once I have the ends. Usually make a variable length one with piece of threaded rod in between the cut off ends of a stock one. Or find one that's too long and press out one end, trim and press end back in and gently tack weld it.

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Got my rods from Cunningham. Beautiful workmanship. Now I can start putting the pieces together. Body is on the frame, firewall is started. Exhaust is together and motor mounts are done. Dana 70 is 9" shorter. Check out flying hammer f.b. page for pictures.
 
I have seen the mechanical injection versions of the 4.5l
They look almost identical to the 3.9l versions.
With all that custom work, why not put a 4v head on it?
Just an idea
 
If I could find one cheap, I would. Are the injector threads the same as the inline 8valve?
 
Smith bros will make any pushrod you'll pay for. They're out of Central Oregon.
 
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