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Mystery 440- Help!

Really looks like a stock bottom end. Depends on the pistons but if they're lighter than stock it'll take quite a bit of abuse. Other questions are how far in the hole the pistons are? Windage tray? Oil pan?
I've broken 440 rods but that was using 1000 gram pistons and buzzin it to 6500.
This is starting to look like it would be worth bolting on a supercharger and sending it to me. Run the heck out of it and if it breaks then you can spend all the cash on a rebuilt shortblock with some tricks. No need to bust it down now. I would however get a shot of the tops of the pistons (try to rotate one so it's at TDC). I would also make sure it has a baffled oilpan of decent capacity and a windage tray, you can change those in the car BTW.
 
If you are dead set in manifolds. I would gasket/port match them and have them extrude honed.
 
When you get the bill for extrude honing, you will learn to love headers...

Chuck (snook)
Agreed. I have sent several intakes, heads and exhaust manifolds to have Extrude hone for various builds. It is expensive. However, if the stock look is what you are after and want to make power it helps. Look at the F.A.S.T
Class racing.
 
For only 550-600 hp, you don't need to extrude hone anything.
 
Really looks like a stock bottom end. Depends on the pistons but if they're lighter than stock it'll take quite a bit of abuse. Other questions are how far in the hole the pistons are? Windage tray? Oil pan?
I've broken 440 rods but that was using 1000 gram pistons and buzzin it to 6500.
This is starting to look like it would be worth bolting on a supercharger and sending it to me. Run the heck out of it and if it breaks then you can spend all the cash on a rebuilt shortblock with some tricks. No need to bust it down now. I would however get a shot of the tops of the pistons (try to rotate one so it's at TDC). I would also make sure it has a baffled oilpan of decent capacity and a windage tray, you can change those in the car BTW.

I need to take the top off to CC anyway to see what I need to do to get it to about 9 to 1 or so for the supercharger. It might already be close enough with those flat top positions.
 
When you get the bill for extrude honing, you will learn to love headers...

Chuck (snook)
Yeah, maybe I need to learn to love headers then.
 
I wanted to thank everyone for helping me out on the this.

Based on your comments, I decided to leave the bottom alone and build from there.
(Unless remcharger thinks the rod bolts came from Walmart.)
 
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With that nice scope...Pull a plug out and look at the top of the piston.

Oem rods are not bad, mopars were all forged, not cast like most gm rods. I'd rather run a factory set then "cheap" chinese set, but past 600hp we run eagle and scat rods. If it has a light pistons that helps them considerably. They likely have been gone through...better picture of the rod bolts would help.
We ran 550-600hp with stock rods arp bolts for years. Even went throuh the traps a couple times at 8300. We have pulled one in two that even had arp bolts....but a cylinder wall was split. Likely any rod would've let go.
I never thought about pulling a plug. Duh! I’ll do that!

BTW- The scope I have is great $39 unit that hooks wirelessly to my phone and can take video too.
Very inexpensive and handy.

Seems like I can't add a Amazon link here, but if you search for this, you will find it.

DEPSTECH Wireless Endoscope, IP67 Waterproof WiFi Borescope Inspection 2.0 Megapixels HD Snake Camera for Android and iOS Smartphone, iPhone, iPad, Samsung -Black(11.5FT)​

 
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I wanted to thank everyone for helping me out on the this.

Based on your comments, I decided to leave the bottom alone and build from there.
(Unless remcharger thinks the rod bolts came from Walmart.)
Those are ARP bolts
Read what @Runcharger Said. Build it, see what it does. Learn from it.
 
Scoped the piston top and found them to be 0.03 over Speedpro L2355f30.
Stock 906 heads are around 90 CC (I think? '70 block and probably stock heads. 906 then, right guys???). Don't want to pull a valve cover today.

Do you guys think I should even bother CC'ing the block/piston area? PIA for me when I know I am pretty close to where I want to be.

Speed Pro says:

Compression Ratios
78.5 cc Heads: 10.17
88.0 cc Heads: 9.37

I was actually hoping for about 9 to 1 anyway for the Procharger blower.

This engine really bites with NA, 9 to 1. No wonder the previous owner had 3.9's in the rear.

Piston P_N .JPG
 
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"Six pack" replacement pistons. They're heavy, wild guess you have 9.5 compression give or take. Try not to rev it above 5500 to give your rods and rod bolts a chance to survive. Forged which is nice.
 
9.2-9.5: 1 is likely pretty close. Most the 906s I have cc'd are less then 90cc. 86-88cc is more typical w new valves and surfacing..imo. probably for what your doing I would figure 9.5:1 though until you measure it. Better safe then sorry. E85 guys runs 9.5:1 with lots of boost.
 
Nothing described in post #1 seems to point to an aftermarket block. Not sure how you came to that. Even hard core bracket racers like me can't afford an aftermarket block and then on hang all the stock parts, heads, ex manifolds, etc.
All the BB Mopars had forged rods, most forged steel cranks. Back in the day I ran thousands of runs at 550 to 600 HP with a stock 440 or 400 block, all with OEM rods and various styles of pistons.
 
Nothing described in post #1 seems to point to an aftermarket block. Not sure how you came to that. Even hard core bracket racers like me can't afford an aftermarket block and then on hang all the stock parts, heads, ex manifolds, etc.
All the BB Mopars had forged rods, most forged steel cranks. Back in the day I ran thousands of runs at 550 to 600 HP with a stock 440 or 400 block, all with OEM rods and various styles of pist
Stock block from 1970.
Thanks for the comments on your experience.
 
The hard part for me is that if I pull the motor, it is never going to end. I have had a few cars that I sold off because they sat so long with no progress.

I guess the scarier thing for me is not pulling the motor. It is what I "need to do" after it is out.

New front suspension? Of course, the motor is out.
Trans swap to an auto or 5 speed? Of course, the motor is out.

Arr...... (But thanks for the confirmation guys.)
That’s most likely what going to happen.

I hope not but sounds like it.
Things get in the way like life and cars just sit.

If the car has 300-350 hp why not leave it as it is?

It sounds like it’s a safe, fun reliable car you can drive anywhere anytime. 300-350 is more than plenty of power even in todays world.

However I know in todays world there’s cars pushing 450-700 stock but how often does that really get used ?
Once you start adding this and that it’s only going to create more possible failures and more downtime.

You might be better off busy building another motor in the side and gathering everything to just install on a weekend so it avoids the possibility having the car turn into a paperweight.
 
OP,

Wise plan; Sounds like you're going to run it as is and, as many have pointed out, if the rebuild was done right with forged pistons (even heavy ones) with factory forged rods and crank and balancing jobs, you shouldn't have any issues with the power you're intending to make (especially in spite of the iron exhaust manifolds) keeping the RPMs below 6500. It doesn't sound like you intend to flog on it at the track relentlessly and, in light of that, I would enjoy it as is and focus on keeping the fuel mixture and timing optimized when you add the blower as that will be far more critical. Good luck with the build and hope to see pics as you progress with the build.
 
Engine good till about 600 hp. Then start getting cap walk on mains. IMO girdle from 500 hp and up. Girdle change where oil pickup fits in pan. Need to move farther down. Need better heads than stock. Can’t move enough air with stock heads vs aluminum. At hp levels you want details become very important. Tolerances must be correct. Best of luck.
All true, you gonna spend 12 k plus to get 550 out of a 440. 440's put rods thru the block first off. And you will need big headers for the big alum heads you will also need. Reliable hp not cheap, do it right or forget it. You can still buy a lot of gas for 12 grand.
 
I'm going to be the naysayer in the bunch. IMO a stock 440 can handle 500HP easily. I would put the blower on this without worry. High RPM's is the real killer, and you don't need to go high with a blower. That said I used to run a stock bottom end to 7000 pretty regularly with no problems. I wouldn't worry about a girdle unless you were shooting for over 800 HP. You have forged rods, and although a forged crank is good insurance, the cast one handles HP well. Besides, the very worst that could happen is you break something and have to pull the engine, right? I do agree about the headers, you have to get all that gas out to get the power.
 
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