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I'd like to know what is required for a 426 engine swap with a 5.7l 300C. Ovbiously, I'd have to get the engine, and I've seen a vendor on here offering them for sale. Sofar, I've only seen one.

What else is required for the swap? Is a new PCM and/or harness required? An exhaust change, I am assuming is also required because the stock stuff won't bolt up, and besides it would be a waste to have stock exhaust on a 426 hemi.

It seems that the price adds up quickly, from start to finish.

Thanks for any info,

greg
 

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I would suggest checking with PPP, they would know for sure. I would guess that at the very least the PCM and TCM would have to be re-flashed for the 6.1 and the injector pulse would have to be modified for the stroke. Headers and 2.75"-3" exhaust would probably be a good fit also. I would be curious to the cost when you get a handle on it. You might want to price a new rear end and half shafts too.:)
 

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what's...

What's involved is about 15 thousand dollars or so!
 

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To do it properly and have everything working as it should you would be looking at the purchase or build cost of the engine, R&R of engine, headers, hi flow cats, cat back, torque convertor, half shafts, edit and lots of misc bits and pieces. $15K min and up.
 

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Depends on your definition of a 426. You can buy the 426 shortblock and install all the 5.7 components on it for $5800 plus install. It just depends on how far you want to take it.
 

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Discussion Starter #8
No, its a 6.1 block which is the exact same as far as swapping parts over. All 5.7/6.1 parts interchange. You take the 6.1/426 bottom end and bolt the 5.7 heads/intake/oil pan on and your done.
Okay, so this isn't all that bad then. No PCM swap or anythink like that. It sounds to me like a straight engine swap.
 

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interesting- how much are you losing 5.7 top end vs. 6.1? Thinking for forced induction situation, need to build the bottom end anyway.
 

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What kind of numbers will you be getting out of this set up,i am very interested
 

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interesting- how much are you losing 5.7 top end vs. 6.1? Thinking for forced induction situation, need to build the bottom end anyway.



What kind of numbers will you be getting out of this set up,i am very interested

You loose a little compression. A 426 with 6.1 heads, 6.1 Cam, 6.1 Intake makes 565hp/600tq on an engine dyno. A 426 with 5.7 heads, 6.1 cam, and 5.7 intake makes 500hp/560tq on an engine dyno. That is with Indy heads and stock cams. If you put the right cam in there with the Stage 3 5.7 heads from us, you can make 560hp/560tq pretty easy.
 

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You can physically bolt a 5.7 head on a 6.1 block but you will have coolant leaks like its nobodies business. The 6.1 heads and block have a additional coolant port that the 5.7s doesn't have. I will try to find a pic of 6.1 and 5.7 heads gaskets to prove this.

If you want to build a 426 and have a 5.7 motor you will need the complete motor PERIOD! However, they do have 392's built off 5.7 motors that you can just bolt stock 5.7 heads on. I won't recommend that since they don't flow enough air to take advantage of the extra hp and the valve springs won't be able to handle the lift of a 392 cam.
 

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You can physically bolt a 5.7 head on a 6.1 block but you will have coolant leaks like its nobodies business. The 6.1 heads and block have a additional coolant port that the 5.7s doesn't have. I will try to find a pic of 6.1 and 5.7 heads gaskets to prove this.

If you want to build a 426 and have a 5.7 motor you will need the complete motor PERIOD! However, they do have 392's built off 5.7 motors that you can just bolt stock 5.7 heads on. I won't recommend that since they don't flow enough air to take advantage of the extra hp and the valve springs won't be able to handle the lift of a 392 cam.
This is completely false. We have 4 cars out there running 5.7 heads on a 6.1 block. Sharadon performance has a 5.7 head on a 6.1 block. You need to use 5.7 head gaskets on the swap and there will be no coolant leaks period. Also, Indy cylinder heads also sells a 426 with 5.7 heads on top as well.
 

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dont mean to hijack but ppp if you already have the 6.1 hemi what all is involved in order to make it the 426? and a round about estimate would be nice also. Thanks
 

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dont mean to hijack but ppp if you already have the 6.1 hemi what all is involved in order to make it the 426? and a round about estimate would be nice also. Thanks
Do you want a 426 shortblock, 426 longblock, or 426 crate engine?

The 426 shortblock is $4804 plus $200 for cometic head gaskets, $50 for lower engine gasket kit. Thats roughly $5100, plus about $2000 for install. With stock heads and cam, this will probably make 440rwhp.
INDY 426 SHORTBLOCK 10.3 COMPRESSION - 6.1-S7-426

The 426 longblock is $8999 and all you have to add is your intake manifold, timing cover, and all the front accessories. This can make approximately 475-500rwhp depending on your headers, converter, cai, tune, and such. Install is around $1600 or so.
426 LONGBLOCK - PPP-426-LB
 
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