[Gmratrod]

So I'm putting a chev 350 into my 53 gmc pickup so now I have to replace my crossmember. what I was wondering is whats the difference between using a boxed plate crossmember to using a single piece bent 3" pipe?

 

[NEW INTERIORS]

So I'm putting a chev 350 into my 53 gmc pickup so now I have to replace my crossmember. what I was wondering is whats the difference between using a boxed plate crossmember to using a single piece bent 3" pipe?

Tubing is stronger because of the corners,, But I have use both for a crossmember.. Not as big as 3'', But have used both with no problems..

When you have the pipe welded are bolted in it will be pulling on both side of the frame to break in half..The 3'' isn't as important as the thickness would be....

 

[gearheadslife]

boxed.. if you ever go ifs as the engine crossmember keeps the mounting points of the frame true.. if sticking with a live front axle,
either.. as long as it hold the engine..

 

[NEW INTERIORS]

Sorry... I thought you was talking about the trans crossmember... :drunk:

Front cross member Box it..:thumbup:
No pipe !!!!:nono::nono:

 

[NEW INTERIORS]

For the trans you can buy nice prebent 2x4s ready to make plates for bolting in. Do not use round tube it will not give good bolting or welding surfaces.

For front engine cradle it should be boxed up. If not already may want to replace if its not a nice heavy junk of steel. That section of the frame should be very strong.

Trans crossmember is just to hold the trans and support.

The front member is structual and very important to how well your finish project will drive and handle real world conditions.

I agree with some you posted but round tubing can be used very easy..Here's one I did using the round tubing.. And you can unbolt it if you needed too..

Here's another one I did with 1''x2'' tubing,, The very samething can be done with pipe,, As far as the front crossmember.. Boxing it is the only way to go..

 

[Gmratrod]

The reason I would like to go pipe is because when you put that much weld into A boxed frame like that your going to end up with distortion from the heat. Even if you jig it up your still going to be welding stress into it. Where as the pipe just has two end caps then welded to the boxed frame. Plus I can't bring my self to buy a cross member as I have a pile of steel here in the shop to build my own. From a strucal aspect I think the pipe would be stronger then boxed plate, I could use hss but I still want to get away from putting to much weld into it.

 

[NEW INTERIORS]

If you think pipe is gone to be stronger.. Go for it... But if you have a press give it a little test and see if your wrong or not..:mwink:

I think you will be surprized at the result...

As far as the welding goes.. When done right you get the same result's tubing or pipe as far as stress goes..

This might give you some ideas..http://www.hotrodders.com/forum/making-willys-frame-148235.html