300-351 swap

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Mar 27, 2009 | 08:19 AM

Lone Wolf #2

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From: Clermont county, Ohio

300-351 swap

I know this has probably been covered many times over but a search did not turn up the info I'm looking for. I'm considering swapping out the 300 six for a built 351 (specifically a 427w from coast high performance) My questions are, do I need to get the computer and harness from a donor truck or can I use the mass air kit from Ford racing, what other side items do I need to get other than the obvious headers, motor mounts, etc. The truck is a 93 sc short bed 2wd. I also know the trans will need to be changed due to the bellhousing bolt pattern, are there any recomendations for a company to get a built trans?

Mar 27, 2009 | 08:23 AM

rostena

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I'm not so sure about your wiring issues but you probably have to get the computer and harness from a donor truck. What I do know is that your tranny will bolt up to a 351, but if your engine is modded alot you might consider a swap anyway.
What tranny do you have?

Mar 27, 2009 | 08:50 AM

Lone Wolf #2

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From: Clermont county, Ohio

E4OD with a B&M deep pan. The truck has 176K on it and everything is starting to get a little tired. The trans. has been overheated a time or two so I doubt it would hold up to a 427w.

Mar 27, 2009 | 09:07 AM

straightsixer

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In my opinion, don't do it. Presently have a stock 351ci and I truely miss the 300ci. Went from about 18mpg to 12mpg with a modest increase in power when switching to the V8. But it sounds like you have more performance goals in mind by doing this swap so good luck.

Mar 27, 2009 | 09:37 AM

rostena

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Quote:

Originally Posted by Lone Wolf #2

E4OD with a B&M deep pan. The truck has 176K on it and everything is starting to get a little tired. The trans. has been overheated a time or two so I doubt it would hold up to a 427w.

It would be smart to replace it then. Personally, I'd get a rebiult C6 with a few performance parts and a shift kit. Thats just my opion tho. Someone else will chime in soon.

Mar 27, 2009 | 11:34 AM

DJdemon6696

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make that 427 carbed.. and use a c6 a stock c6 can hold up to 400 hp

for the swap you will need v8 chassis perches and engine mounts for it to fit.. nothing else exept exhuast wich im guessing you are going custum with longtube headers in this case a doner V8 truck will do perfect

im doing a 300 to 302ho swap right now all i needed to make the engine fit was a v8 chassis perches that fits behind the corssmembers and v8 engine mounts

Apr 1, 2009 | 06:03 AM

Lone Wolf #2

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From: Clermont county, Ohio

I want this to be injected for driveability reasons, If I was going for straight power a carb would be good, but this will be a regular driver ( not daily) also I want to keep the E4OD for mileage purposes ( the big displacment will hurt this enough.) Thanks for the suggestion though. I've already found the motormounts and perches at Jeff's BG, Not sure on headers though.

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Apr 1, 2009 | 11:45 AM

Conanski

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From: Ottawa, Ontario

Quote:

Originally Posted by Lone Wolf #2

I'm considering swapping out the 300 six for a built 351 (specifically a 427w from coast high performance) My questions are, do I need to get the computer and harness from a donor truck or can I use the mass air kit from Ford racing,

Here's a quick snapshot. The tranny will need to be rebuilt and upgraded, you also need V8 engine mounts and towers, V8 rad, a 5.8 distributor, and a 5.8 flexplate. Since this is a transplant you need a complete V8 powertrain wiring harness(engine and trans) and MAF truck computer since you have an E4OD.

Now the bad news. A built 427 will NOT run on a stock computer, period. So you need a tuner to recalibrate it for the 36-42lb injectors and 80-90mm MAF meter the motor will need, and 255l fuel pumps to feed the beast. You can also count on a rearend rebuild with better axles, diff, and ladder bars so it doesn't twist up like a pretzel the first time you get traction. This is not a cheap project by any stretch.