454 install and fitment ????

[trkklr77]

first off i have a 69 with full 73+ 2wd susp and motor mounts and am trying to fit a 77 454 and th400 tranny.

i have a few problems and maybe im over thinking the situation

the tranny mount is about 1" to far back from the last predrilled mounting holes for the cross m.

1 is that typical with the susp swap, the motor swap, motor mount swap?

the dist is also jambed in close to the fire wall,

is it supposed to be with in a 1.5", i have about 5" to the rad from the front of the water pump with a short pump.

i have thought up about 5 very pluasable solutions but dont know which way to turn and what is going over board or half @$$ing it

1 move the motor mounts forward and gain the room behind the dist and tranny lines up, BUT the mount brackets are right on the edge of the front cross members and i would have to redrill all 8 hole on cross m and frame rails

2 make offset upper motor mount halfs. again getting the spacing and linning the tranny cross up. [unless there is a aftermarket setup available

3 redrill the frame for the tranny cross

4 redrill the tranny mount holes for the cross

5 bolt in a offset plate for for the tranny mount.

what have you guys done or would do?? sorry this is so noobish

[71/454]

I would move the motor mounts forward. Th reason for me would be the distributor. I have 81 mounts in mine and they are moved ahead of there location where they would be on the 81. I also have a 454 but have the long waterpump and have just enough room for a steel blade fan with a 3/4 or 1 inch spacer so i can get my hand in between the fan and the rad. There is a great article about using 73 and up mounts in the faq section. Hope this helps

[TP from Cntl PA]

The guy who had my K put a 454 in it with a SM465............It was tight on both ends, the GM HEI distributor was so close to the firewall, anything more than a piece of paper wouldn't fit behind it..............And with the fan shroud on the radiator, it was close on the front side too if you ask me. They made their own motor mounts from the small block ones and cut and rewelded them to use the stock holes in the frame..........Which would have worked, if they then did cut half of the backside of one off to clear the exhaust manifold on the passengers side.

[RSRXION]

Use the front frame holes for the engine mounts. I just installed a 76 model 454 and TH-400 in my 72. My truck was originally a 350 with a 4 gear. I used the towers and mounts from the 76 donor 1 ton and everything nearly fell into place.

On the towers, one of the holes will line up perfectly. Use the forward most hole on the top rail and bolt your tower in place adjusted into the fully forward position. Then use an awl to scribe the other 3 locations to drill out either the frame holes or the tower holes. I drilled out the tower holes since I can replace them anytime and return the frame to stock. Be sure and use a grade 8 flat washer between the bolt and the tower when you do the final install.

Once you have bolted the towers tight in place, feed that big block into the engine compartment. One little note here.... I decided to pull my grille, core support and right front fender/ inner fender off for this task. It was amazingly simple to just slide the big block and trans in as a unit without having to wrestle 1,000 pounds of HEAVY into the engine compartment. If you've got nice valve covers I would highly recommend using some junkers for the install. The brake booster assembly is murder on the drivers side cover.

Once you've got the rat motor in place and the trans dangling out behind it use a floor jack and a piece of plywood under the trans pan to bring it into place. This will allow you to get your horizontal bolts through the insulators and towers. Once they are started and nuts are on them, DO NOT tighten them up yet.

Jack the trans up using the aforementioned jack and bring it into just above the installed position. Basically, jack it all the way up against the body. By the way, if you don't have a high hump trans tunnel, you're gonna need one. Slip the later model crossmember into place and start the bolts on the trans mount. Then locate the factory drilled holes in the frame and install the bolts to secure the crossmember to the frame. Install the bolts from the bottom and put the nuts on the top of the frame. This makes it a little neater install and it also protects the bolt threads from rock damage down the road. You'll be glad you did if you ever have to pull it all back out. be sure and use lock nuts on these crossmember to frame bolts.

Once the crossmember is started and you like its' location, lower everything down into place and tighten it up. Don't forget about your engine mount bolts.

What you'll end up with is a nice install with a factory look about it. I had my 454 in and out several times getting everything figured out and I can assure you that this is the best install formula you'll find. The engine looks like it came in the truck, the distributor has adequate clearance and you can get your hand between the HEI cap and the firewall. All of the cables and lines bolted right up, and the fan has about 2 inches clearance between it and the radiator. Be sure to get yourself a big block shroud.

I've attached a few pictures if it helps. Anything else I can do, just let me know. Good luck, Dean 479-263-3326

[trkklr77]

sorry for the delayed responce,




after seeing alot of pics and a few bbc trucks in person now i think its goin to be ok. i am not that much farther under the firewall than others and should be able to pull the dist minus the cap.

as fot the motor mounts, i was able to get 3 hole to line up and only needed to drill the front upper out some, so that what i went with.