Swaping Engine X-member for 73up Style

[Burt4x4]

Please check my post here:
http://67-72chevytrucks.com/vboard/s...hreadid=100788

I need to know if the frame monted engine mount plates fit inside the frame rails. Or do I have to spread the frame open more to get them in....
I have a pic of an article in my other post..
Any and all info is needed..

[Burt4x4]

Here is the article I have:

[Burt4x4]

See that last pic on the bottom left how thoes plates are IN the frame. The ones I have do not fit in the frame.....
Bent plates?
Bent Frame?
Anyone.............

[Burt4x4]

TTT

[454_72_4X4]

I can't really help you with the frame mounts bit I was just wondering what the advantage of swapping crossmembers to the newer style is.
(Other than the newer style "clamshell" motor mounts.)

[Bram]

Looks to me like you could remove the oil pan without raising the engine, that’s a big advantage. I think that this would be an awesome conversion! I'm going to look into this one more.

[Burt4x4]

One of the main reasons I am doing this is so I can drop the oil pan without moving the engine or xmember. Even with my 350 I could not drop the pan with my factory x-member in my 72K5. The engine would have to be lifted or suspended from the top and then remove the Xmember to alow the pan to drop off.
Also what I read is when installing a BBC in a first gen K5 using the factory Xmember only one style of oil pan can be used and very few headers will work.
And lastly the engine mounts on a 73+ Xmember has alot more choices to use, as far as aftermarket stuff. Example would be the Off-Road Design compition engine mounts. They do not work with my factory Xmember and I want to run thease with my FI454 build up. I don't want to worry about busting an engine mount with this Troque Monster FI454 I am building.

I have one of my club members bringing me a new set of 73+ mounting plates. This will alow me to figure out if my frame's C needs to be opened up or if the plates I currently have are bent. From all that I have read the frame plates should fit inbetween the C with out bending the frame wider.....

I still have yet to talk to ANYONE on this planet that has actually done this modification before. Heck I figured if there is an article published in 4x4Power (Petersons) then it should be fairly common...guess not?

[454_72_4X4]

My dad did this conversion on his 68 but it was just because that's the parts he happened to have. (he was converting from 2wd to 4x4 and was using a mid 70's donar frame and running gears.

I can understand the oil pan thing. That might be handy, (although I'd hope not to have to do it! )

Now if it makes more clearance for headers I'd sure like to know that. If it does put me in line!
Are you going to put the 454 in the factory small block location? Meaning the engine will still sit right where it would with the original Xmember?

[Bluegoose972]

This might be a silly question, but how often do you really plan on pulling your oil pan off? I have never actually had to pull my pan before and I'm sure that I have been lucky. But if I have a problem bad enough to require pulling the pan, I might need to just spend the extra half a day and pull the whole engine.

I agree that a better setup is needed for the motor mounts. My engine is putting out almost 500 ft-lbs and I'm sure that it is going to be a problem. I spoke with Blackbird about this situation and he said that he actually runs a chain/turnbuckle setup on the driver's side of the engine that runs from the cylinder head to the frame. By cinching down the turnbuckle, he's able to prevent alot of stress on the motor mounts. This is mainly in his hi-performance setups, but would also work on a street rig.

Just my $0.02. Hope you have more luck than I did. I'm still running manifolds since I couldn't get a set of headers to fit without major rework on the frame and small block crossmember.

[Burt4x4]

Time is something I don't have much of being a family man so if I ever do need to drop the pan the less time it takes the better I hope I never need to drop it once I get it installed...but never say never right
Yes the 454 will go in the same spot as my 350.
Keep in mind this is a trail rig so I have a 3"body lift and I will not have any clearance issue. I am running a small cap computer controled dist. to


Thanks for the replys.....If you guys want me to keep you posted on this I will?

Burt

[Bluegoose972]

Definitely keep us posted. This swap isn't as straight forward as many believe.

Off topic....Where did you get your rollbar? I just purchased a unit from S&W that looks similar to yours. Since yours is a cage setup, did you mount it to the frame? What would you do differently if you could....Say shifting bars around or you would add this brace...etc. Any input would be great.

Rick

[Burt4x4]

Hey Rick, The cage I have was a custom built one by myself and a pipe bender friend on his spare time. He had one of thoes big hydrolic benders that you just push a button to bend.
Changes would have been:
incorporate my front seats and center consol into the cage with floor bars.
Put a rear Halo to protect the rear seat folks better.
I will someday add ths stuff...someday.
No I did not goto the frame. I did choose my mounting spots to be ontop of the body's crossmembers to help prevent 'punch thru'.
Most of the wheeling I do is real slow trail stuff so if I ever did go over it would not be at a high rate of speed..more of a flop.
Incorperating the seats would give alot more 'cage' pertection and horizontal strength as well. (I cannot spell woth beans).
heheheh

Have a Great Day
Burt