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hi you can call me mater
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Discussion Starter #1
Is the crankshaft from a 4.2 f150 forged? And if I was to put that in an extra motor I have will I need to swap over the pistons?
Cause i'm thinking of buying forged pistons and rods along with the 4.2 crank and port my extra set of heads and Intake and put a big cam and drop it all in a 2003 mustang v6 that's my girlfriends its white like mike's

03cristian
 

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No it is not forged.
Mike's car isn't forged either.
 

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hi you can call me mater
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Discussion Starter #3

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hi you can call me mater
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Discussion Starter #5

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Negative, only forged crank is the super coupe.
 

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hi you can call me mater
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Discussion Starter #7
Negative, only forged crank is the super coupe.
So I could get a crank from a SC and swap it in my extra motor?
Along with forged pistons and rods and I'd be set right?
Maybe get the motor bored to 4.3?
How much hp could I expect with a Cam from you Kyle?

03cristian
 

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So I could get a crank from a SC and swap it in my extra motor?
Along with forged pistons and rods and I'd be set right?
Maybe get the motor bored to 4.3?
How much hp could I expect with a Cam from you Kyle?

03cristian
Oh dear you sir need to do some heavy reading!

- yes s/c crank, and rods/pistons specific for it yes (they have an off the shelf piston you can get)
- you can't bore anything to 4.3
- a cam on an n/a setup?
 

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hi you can call me mater
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Discussion Starter #10
Oh dear you sir need to do some heavy reading!

- yes s/c crank, and rods/pistons specific for it yes (they have an off the shelf piston you can get)
- you can't bore anything to 4.3
- a cam on an n/a setup?
I thought i've read somewhere where they bored a block from 3.8 to 4.3 ?
Did I read wrong?

03cristian
 

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The 4.2 has a different stroke on the crank.

Sent from my phone, in your back seat...
 

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The SC cranks rear main journal is oversized by 0.010" (or under 0.010" I can't remember which way) so you would either have to get a bearing thats under/oversized or machine the block or crank.

4.2/4.3L is created by stroking of the crank (longer stroke = higher engine displacement). To get to 4.3L you have to use the 4.2 crank and then bore the block I believe 0.030" over, which puts you I think technically puts you around 4.25xxL ~ 4.3L with rounding.
 

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4.2= 3.74" stroke
3.8= 3.40" stroke

Both have a bore of 3.80"

Scat carries the 4.2 crank in their 9400 series, it is in fact cast. My crank is a chinesse crank, probablly the same company who makes scat but scat puts their name on it.

To get true 4.3l the over bore is .060. Mine is bored .040 and is soomething like 4.275L so I just call it a 4.3L.
 

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hi you can call me mater
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Discussion Starter #14
4.2= 3.74" stroke
3.8= 3.40" stroke

Both have a bore of 3.80"

Scat carries the 4.2 crank in their 9400 series, it is in fact cast. My crank is a chinesse crank, probablly the same company who makes scat but scat puts their name on it.

To get true 4.3l the over bore is .060. Mine is bored .040 and is soomething like 4.275L so I just call it a 4.3L.
So does that set up yield more power?

03cristian
 

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4.2= 3.74" stroke
3.8= 3.40" stroke

Both have a bore of 3.80"

Scat carries the 4.2 crank in their 9400 series, it is in fact cast. My crank is a chinesse crank, probablly the same company who makes scat but scat puts their name on it.

To get true 4.3l the over bore is .060. Mine is bored .040 and is soomething like 4.275L so I just call it a 4.3L.
+1 mine was bored .50 over and i just say 4.3, wonder how much diff that actual .1 really has, my guess is not much at all but hey every little bit counts right?
 

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hi you can call me mater
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Discussion Starter #17
+1 mine was bored .50 over and i just say 4.3, wonder how much diff that actual .1 really has, my guess is not much at all but hey every little bit counts right?
Right!

03cristian
 

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+1 mine was bored .50 over and i just say 4.3, wonder how much diff that actual .1 really has, my guess is not much at all but hey every little bit counts right?

punch these numbers in on wallace calculator and my engine is 259.88ci and your is 261.24ci. Both imo are 4.3l engines.

Extra displacement always helps spool a turbo, but I dont think it counts for any real noticable power gains. Most of the time the power is made with the top end of the motor, cam, heads, and intake.
 
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