67-72 vs. 73-87 Crossmembers for Pancaking

[Frizzle Fry]

Are they exactly the same? I know they'll swap over, but what are the differences? Any? Couple bolt holes? I'm thinking about trying an xmember pancake and I'd like to source a spare so I don't have to pull mine until I have the mod'ed on ready to go. BTW, I'd do a dropmember but I don't want to have to have another drive shaft made etc... This way my engine stays put.

[jlaird]

One I can think of is I believe the brake lines are routed to the front for the 73-87 vs the rear of the cross member for the 67-72.

[SCOTI]

Mike, I would say there might be more clearance issues using the later model c.members. It might be that the flange of the c.member @ the u-bolts is a deeper depth vs. the earlier years.

I know XXL's c.member was notched 1.5" & only required minimal clearancing. I tried for that using a post-73 crossmember on my 68 & there's no way it would have worked w/o cutting the outer u-bolt nut + threads in half which IMO is not enough material to keep things in place.

I spaced the c.member up using shims & wound up w/a 1.125" notch w/.125" clearance from lock-to-lock. I removed the reinforcement 'pad' under the u-bolt (outer side only) & had to cut the extra threads above the u-bolt nut off for clearance.

Check w/XXL or CaptKaos. I'm not sure who else is running one that's actually got all the steering linkage installed/tested.

One I can think of is I believe the brake lines are routed to the front for the 73-87 vs the rear of the cross member for the 67-72.

You can technically put the brake lines where ever you want regardless of c.member year model. I had post-73 brakes/lines w/my stock 68 c.member before doing the notched c.member (which never saw the road because of Mr. Porter).

[jlaird]

Mines finished with all steering linkage connected. Let my know if you have any questions. I also did 1.5" notch with a .25" spacer to get things to work.

josh

[SCOTI]

Originally Posted by jlaird

Mines finished with all steering linkage connected. Let my know if you have any questions. I also did 1.5" notch with a .25" spacer to get things to work.

josh

Yours was the only other one that I knew of that was close to completion but I wasn't sure if you finished the steering stuff.

Do you think the 1.5" would have worked for you?
What year c.member did you use?
What year steering gear (tie-rods, draglink, c.member u-bolts)?

[Frizzle Fry]

What's this spacer you guys speak of?

[SCOTI]

Originally Posted by Frizzle Fry

What's this spacer you guys speak of?

I made a .250" plate that sandwiches between the c.member & the frame. I also had to make some that go between the m.mount towers & the c.member.

These aren't necessary if the notch is done in the exact amount. But, I did a 1 3/8" notch only to find it wouldn't work for my parts combination. I could find another c.member & cut it less, or.... make spacers. Spacers it was.

[Frizzle Fry]

ahh gotcha. I'm thinking about choppin out just 1". That'll use up the rest of the space I created with the fender sectioning. I want to do a crossmember section rather that notch to retain my current pan clearance. You guys agree with that reasoning?

[SCOTI]

Originally Posted by Frizzle Fry

ahh gotcha. I'm thinking about choppin out just 1". That'll use up the rest of the space I created with the fender sectioning. I want to do a crossmember section rather that notch to retain my current pan clearance. You guys agree with that reasoning?

100%.

[jlaird]

Originally Posted by SCOTI

Yours was the only other one that I knew of that was close to completion but I wasn't sure if you finished the steering stuff.

Do you think the 1.5" would have worked for you?
What year c.member did you use?
What year steering gear (tie-rods, draglink, c.member u-bolts)?

No, the 1.5" would not have worked. The outer ubolt on each side was the major issue. There is clearancing to do on the front lip of the cross member, but that was no big deal. I used a 69 crossmember. Outer tie rods are 73-87 for use with the 73-87 drop spindles. Draglink is 69. U bolts were upgraded to the thicker 9/16" thick ones.

[grnddwn]

I also did a 1.5 notch then installed a 0.25 spacer in mine too. Over the past 3 years I've grown tired of the bump steer and I am switching over to a dropmember this year. The only steering shaft interference I had was after the bodydrop and that was minor just a little control arm mod to fix. Other than that the steering has been fine (except the bump steer but I drive it pretty low) for 3 plus years.

[Frizzle Fry]

You shouldn't have bump steer if you move the inner rod ends and associated pieces/arms up the same amount as the total CM drop.

I am thinking along those lines for possibly going to a rack. I've never done either of these before but from what I've read it all comes down to the right rack width and placement. Any insight?

Originally Posted by grnddwn

I also did a 1.5 notch then installed a 0.25 spacer in mine too. Over the past 3 years I've grown tired of the bump steer and I am switching over to a dropmember this year. The only steering shaft interference I had was after the bodydrop and that was minor just a little control arm mod to fix. Other than that the steering has been fine (except the bump steer but I drive it pretty low) for 3 plus years.

[PBFAB.COM]

Originally Posted by Frizzle Fry

You shouldn't have bump steer if you move the inner rod ends and associated pieces/arms up the same amount as the total CM drop.

I am thinking along those lines for possibly going to a rack. I've never done either of these before but from what I've read it all comes down to the right rack width and placement. Any insight?

It's a lot of work to incorporate a rack and pinion onto a factory crossmember... and have it function properly. The main issue is rack mounting clearances at the u-bolts that secure the LCA. If I were to section the factory crossmember (we all know what I would really do!), I would keep the factory steering box/linkage and move it up.

[gringoloco]

Originally Posted by porterbuilt

...I would keep the factory steering box/linkage and move it up.

Yep. This will require a lot of strengthening where you cut the frame though. I think if you're gonna go R&P, you might as well go DM. It really is a nice piece that just kinda falls together. It would also give you a good reason to take advantage of that monster notch...

[smashingchuck]

I moved everything up 1.5 inches including all the steering components and notched the frame for the ties rods. My crossmember is not pancaked, just channeled for the frame, and I shortened the motor mounts so the motor is in the stock location. Work great - I've had it done for over 5 years now.

[Frizzle Fry]

Thanks smashingchuck. I actually read some of your previous posts about it before posting this thread. Got any pics?

[Dinos63]

frizzle, This is the one that was in my panel and all the stock steering worked, hope this helps I also have some pics of it installed also

[smashingchuck]

not any very recent or useful ones. Truck is at the bodyshop right now, too. Otherwise I would just go take some.

[Frizzle Fry]

How deep is your love... er notch on that Dino?

Thanks smash. Looks like you've done a whole lotta mod'in to that truck. I'm not sure how much I could get away with before the BBC pan would hit without sectioning. I'll have to look.

[smashingchuck]

I have a small block, and it clears no problem. Not sure on the big block. I guess you might be better off to do it how Dino's is. If you still need em when I get my truck back I'll snap some better pictures.

[Jeffs70]

I have been curious of doing the pancaking with my c-member, but then again I have this thought in my head it would be a bad idea due to the fact It would Drive everything up ward from the bottom, that including the lower Control Arm's and that causes an Issue with everything in foul play don't it?

[truckeez]

What does pancaking a crossmember mean? vertically sectioning?

[SCOTI]

Originally Posted by truckeez

What does pancaking a crossmember mean? vertically sectioning?

Yes.... Just like in the above pics.