292 to 427T industrial swap, in C30. Many questions on fitment.

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AyWoSch Motors

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@Dooley

Youve done this before, right?
I know you weren't a huge fan of it, but im kinda set on wanting to.
Got any info, or big things that were a pain? Got any pics?
 

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Not only is the BBC clamshell mount different, it actually is supposed to mount in different holes. The SBC mount will work, usually.

The big problem I see is that you didn't get a flywheel with that motor. 427T is internally balanced and will need a specific flywheel different from a 454.
 

AyWoSch Motors

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Not only is the BBC clamshell mount different, it actually is supposed to mount in different holes. The SBC mount will work, usually.

The big problem I see is that you didn't get a flywheel with that motor. 427T is internally balanced and will need a specific flywheel different from a 454.
I did get a flywheel with that engine actually, but im running it with an automatic, so it has a flexplate right now.
 

AyWoSch Motors

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Well its in, sorta. Trans lined up, my new mount lined up, lined up and went on the trans, and is lined up on the mounts. Everything seems to clear all the way around it. Only issue is, its seems the pan is hitting the crossmember a little tiny bit. Gonna pull it again, and see if i can "massage" it a little bit.
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Bextreme04

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I did get a flywheel with that engine actually, but im running it with an automatic, so it has a flexplate right now.
Hopefully the right flexplate. The same thing holds true on that. A standard 454 flexplate WILL NOT work. I suggest you just go get a normal truck pan for that. Standard Mark IV 454 pan for a square will bolt right up and obviously clear everything just fine
 

bucket

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Internal balance big blocks use the same flexplate as a garden variety pre-'86 small block (except the 400). Bolt pattern for torque converter can be different, but many flexplates have two bolt patterns. Elongating 3 holes works too.
 

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@Dooley

Youve done this before, right?
I know you weren't a huge fan of it, but im kinda set on wanting to.
Got any info, or big things that were a pain? Got any pics?
Never followed a "6" with a Big Block.
Replaced small block and 6.2/6.5 also.
You will need a hydroboost lower power steering bracket for the big block.
The small block I replaced with a steel crank 454 out of a 2WD Suburban.
I used the motor mounts from the Suburban.
The Big Block T replacement I used the Diesel mounts from the D30.
Hood clearance was close.
No wide problems or at rear of tall deck.
You can get aftermarket intakes for long or short distributors.
I went with short.
This is my go to on the fuel pump for this engine swap.
https://www.summitracing.com/parts/CRT-M4530
 

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AyWoSch Motors

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Internal balance big blocks use the same flexplate as a garden variety pre-'86 small block (except the 400). Bolt pattern for torque converter can be different, but many flexplates have two bolt patterns. Elongating 3 holes works too.
Hopefully the right flexplate. The same thing holds true on that. A standard 454 flexplate WILL NOT work. I suggest you just go get a normal truck pan for that. Standard Mark IV 454 pan for a square will bolt right up and obviously clear everything just fine

The flex plate is off a 70s 305 i bought for parts. Its a even 6 bolt pattern, matches my 6 bolt converter perfectly, i test fit it.

The pan looks like its going to be the only issue. Its massive. If it will fit, ill it, but if wont, ill have to change it.
 

AyWoSch Motors

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Never followed a "6" with a Big Block.
Replaced small block and 6.2/6.5 also.
You will need a hydroboost lower power steering bracket for the big block.
The small block I replaced with a steel crank 454 out of a 2WD Suburban.
I used the motor mounts from the Suburban.
The Big Block T replacement I used the Diesel mounts from the D30.
Hood clearance was close.
No wide problems or at rear of tall deck.
You can get aftermarket intakes for long or short distributors.
I went with short.
This is my go to on the fuel pump for this engine swap.
https://www.summitracing.com/parts/CRT-M4530
It has a hydroboost brake/power steering, and matching power steering pump, but bracket is going to be fun to fine.

Im going to leave the stock intake. Seems to be fine, and low enough. Also already had a long shaft HEI that works fine.
Intake is square bore already, so ill just run my AFB and my stubby short eddy air cleaner. Looks like itll work.

Did you have any clearancing issues at the pan? You put yours in a 2wd or a 4wd?

Also did you use a stock intake on either of your builds?
 

Dooley

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It has a hydroboost brake/power steering, and matching power steering pump, but bracket is going to be fun to fine.

Im going to leave the stock intake. Seems to be fine, and low enough. Also already had a long shaft HEI that works fine.
Intake is square bore already, so ill just run my AFB and my stubby short eddy air cleaner. Looks like itll work.

Did you have any clearancing issues at the pan? You put yours in a 2wd or a 4wd?

Also did you use a stock intake on either of your builds?
Both trucks were 30 Series 4X4 with a T400 transmissions.
The only tall deck I used a Dart because the stock one was a double thermostat version and was huge.It allowed me to use a standard water pump.
Since I was changing it I decided to use the short shaft to take the extra room at the rear of the engine.
 

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Ichy62

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I swapped a (low deck) 396 into a 74 shortbed, perhaps ignorant luck, but it dropped right in, had no issues but I had heard in the years since that the true big block frame brackets located the engine slightly forward perhaps. Had no problems with the headers either. The height difference is only .4inch "up and out", so if you are using stock manifolds, fair bet no fit issues there. As far as the accessory drive, the alternator would mount slightly higher as the pivot bolt went into one head front hole so possibly only a bit longer belt there. The "max 4000 rpm" deal may be partly the rpm limiting carb setup they had, but really no need to rev it much more than that. The 427 only has a 3.76 stroke and has a steel crank so no worries there either. There are intake manifold spacers available to install a standard 4 barrel intake if needed. For me it was a fantastic swap that entirely changed the character of the truck, wish I hadnt sold it :-/
 

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Craig Nedrow

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How did I miss this!! ! 10.2 tall deck block is Nirvana to me, 4.5 stroke 4.310 bore 525...you lucky dog.
 

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