Will 383 pistons work in a 426 Wedge ?

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Brooks James

Brooks James

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I see that 383 std bore and 426 Wedge have the same 4.25 bore ?
I have a virgin 1965. 426 Wedge with forged crank and rods
That I want to build to eventually put in my Dart.
Cast or hypereutectics won't work, on a 200 HP nitrous shot
 
2.083 would theoretically be a zero deck piston in a blueprinted 10.725 block (413, 426, 440)
So, It depends on the compression height of the 383 piston. Anything over 2.00 might be serviceable, depending on compression ratio desired. A domed 383 might even work, if the ch is too low.
Time to warm up the calculator and do some research.
 
The stock compression deck on a 383 is about 1.93.
That is about .150 shorter than the stock compression deck
on a 426.
Would they fit = yes.
Compression ratio would be around 7 to 1 or a bit less.
 
GTX John is dead on.
It CAN be done, and work well...... with .100 longer Hemi rods. But buying a set of hemi rods to use a shelf piston would be a bunch more money than buying a set of pistons FOR the 426W, even if you have to buy custom.

Edit: icon 1.912 383 pistons and molnar .100 long hemi rods would be .009 out of the hole in a blueprinted 10.725 block
2nd edit: a low compression 383 piston, 426/440 rod, and a 4.150 crank can work too. But if your gonna stroke a 426W, why not just buy a kit.
 
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33IMP said:
GTX John is dead on.
It CAN be done, and work well...... with .100 longer Hemi rods. But buying a set of hemi rods to use a shelf piston would be a bunch more money than buying a set of pistons FOR the 426W, even if you have to buy custom.

Edit: icon 1.912 383 pistons and molnar .100 long hemi rods would be .009 out of the hole in a blueprinted 10.725 block
2nd edit: a low compression 383 piston, 426/440 rod, and a 4.150 crank can work too. But if your gonna stroke a 426W, why not just buy a kit.
Click to expand...
I couldn't find a full forged stroker kit for the 426.
Egge has pistons, cast or hypers, for 1k
Yes, agree it looks like custom pistons
 
No stroker kits for a 426W? Then look for a forged 383 piston around 1.88 c.h. (or less) 383 flattop at 1.88 might be a bit too much compression for pump gas.
At $1000 for a cast or hyper for a 426, I'd definitely start looking for an alternate route.
 
Racetec/Autotec will make one change to a shelf piston for free. Too bad they don't even list a forged piston for a 383.
If you want a piston for a Ford flathead....or 312 y-block, .... or a pinto....
THAT they've got.
And literally a thousand varieties of Chevy pistons.
 
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I found a forged kit, finally,
from Mammoth racing
4.375 stroke
4.280 pistons
7.1 inch rods
505.55 cubic inches
$2600

Finally I'll be in the 500+ CID Club lol
 
Brooks James said:
I found a forged kit, finally,
from Mammoth racing
4.375 stroke
4.280 pistons
7.1 inch rods
505.55 cubic inches
$2600

Finally I'll be in the 500+ CID Club lol
Click to expand...
505 ci ? where is this kit listed I can't find it on their site.
 
Brooks James said:
I found a forged kit, finally,
from Mammoth racing
4.375 stroke
4.280 pistons
7.1 inch rods
505.55 cubic inches
$2600

Finally I'll be in the 500+ CID Club lol
Click to expand...

Then you still have to add the cost balancing, bearings, shipping, and sales tax.

My kit is $3335.79 complete for any cubic inch size big block up to 541", and you get a Molnar Technologies crankshaft and connecting rods, ICON pistons, and King XP bearings.

[FOR SALE] - 541" Molnar Technologies Complete Balanced Rotating Assembly for 440 RB Block - New

Tom
 
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IDK, I got 504.73c.i., w/a 4.285" bore & 4.375" stroke.
 
I'm hesitant to take the 426
PROSTOCKTOM said:
Then you still have to add the cost balancing, bearings, shipping, and sales tax.

My kit is $3335.79 complete for any cubic inch size big block and you get a Molnar Technologies crankshaft and connecting rods, ICON pistons, and King XP bearings.

[FOR SALE] - 541" Molnar Technologies Complete Balanced Rotating Assembly for 440 RB Block - New

Tom
Click to expand...
Does that price include shipping ? Ok, the 426 has a 4.25 bore
Ur 541 kit has 4.375 bore , a .125 over bore from
4.250, am I misinterpreting something ?
 
The cost of all big block kits are the same regardless of size. I posted the 541" kit as an example of what is included in my kits.

I actually just looked into building a kit with a 4.28" bore, however the available pistons are not going to work with a 4.375" stroke.

Below is what I've come up with.

517.9 Cubic Inch

4.28" 1.318" compression height ICON pistons 12cc dish

7.100" Molnar Rods

4.500" stroke Molnar crankshaft

10.725" - 1.318" - 7.100" - 2.25" (half the stroke) = .057" in the hole

Using these numbers with a .042" compressed gasket and a 78cc chamber head it would yield 10.36 to 1 ,With an 84cc head it would be 9.89 to 1
.038" compressed gasket and a 78cc chamber head it would yield 10.44 to 1 ,With an 84cc head it would be 9.96 to 1

You can alter the compression ratio outcome with a little decking of the heads and/ or block, or playing around with the head gasket thickness.

Tom
 
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The math is:

Bore x Bore, or Bore Squared 4.28" x 4.28" = 18.3184"

x 4.375" stroke = 80.143"

x 3.14159265359 (Pi) = 251.77666

x2 = 503.55"


Or in the case of using a 4.50" stroke crankshaft it would be:

Bore x Bore, or Bore Squared 4.28" x 4.28" = 18.3184"

x 4.50" stroke = 82.4328"

x 3.14159265359 (Pi) = 258.9702789

x2 = 517.94055578"

Tom
 
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PROSTOCKTOM said:
The math is:

Bore x Bore, or Bore Squared 4.28" x 4.28" = 18.3184"

x 4.375" stroke = 80.143"

x 3.14159265359 (Pi) = 251.77666

x2 = 503.55"


Or in the case of using a 4.50" stroke crankshaft it would be:

Bore x Bore, or Bore Squared 4.28" x 4.28" = 18.3184"

x 4.50" stroke = 82.4328"

x 3.14159265359 (Pi) = 258.9702789

x2 = 517.94055578"

Tom
Click to expand...
Thanks a 518 will definitely work, when the time comes,I will definitely consider your offer.
 
You have discovered the major problem with a 413/426W......piston availability. Even 383 stock replacements tend to have slightly too much compression for modern gas, and the forged selection is getting pretty thin for a 383 too.
But I tend to agree... if your gonna spend custom piston money for a 426W, might as well stroke it to boot.
But to tell the truth, I think I would use a 3.91, or 4.15 stroke, and just pay the piper for a custom piston.
($1000 for a cast piston is criminal, imo). BBC con rods in assorted lengths might make coming up with a workable combo easier.
You do know that a GOOD 426W block can probably go .070..... to standard 440 bore size. (that's only .005 of material removed more than a .060 piston.
 
Brooks James said:
I found a forged kit, finally,
from Mammoth racing
4.375 stroke
4.280 pistons
7.1 inch rods
505.55 cubic inches
$2600

Finally I'll be in the 500+ CID Club lol
Click to expand...
A lot of 500+ cid guys don't make what my 470 does
 
The 470 Engines always make more HP than we
predicted. They are a affordable build and can use
a OEM made in US old school Crankshaft.
 
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