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-   -   47-55.1 HELP... 1951 3100 fr. Frame rail hole pics. (https://67-72chevytrucks.com/vboard/showthread.php?t=802134)

portworks 03-02-2020 08:51 PM

HELP... 1951 3100 fr. Frame rail hole pics.
 
I'm attempting to install a gearhead 47 to 54 3100 ifs " Bolt on" kit on my 51 3100.
The problem is the frame has several other holes drilled.
The template plate doesn't seem to line up with any holes.
I would like to see the factory holes, and or the correct holes to use for this kit, which looks like a speedway copy.
Thanks in advance.

dsraven 03-03-2020 12:06 AM

Re: HELP... 1951 3100 fr. Frame rail hole pics.
 
would this help? maybe explain how it is supposed to go together anyway?
does your frame still have the front spring mount intact for a reference mark?

https://static.speedwaymotors.com/pdf/91044754.pdf

portworks 03-03-2020 08:23 AM

Re: HELP... 1951 3100 fr. Frame rail hole pics.
 
Yes I have looked at these instructions and their aren't any holes that align with the template provided.
Was just curious to see someone else's frame rails for hole identification.

dsraven 03-03-2020 09:45 AM

Re: HELP... 1951 3100 fr. Frame rail hole pics.
 
do you mean the truck has had an ifs cross member installed at one time and there are holes in the frame where it used to be but it is now removed and you have a new one to install?
it doesn't matter how you slice it, you simply need to find your axle center line and go by the instructions to get the new cross member in the right place. if there are holes previously drilled they may need to be welded closed and ground smooth so you start out with a clean slate. trying to make your new cross member fit in the spot where a different cross member has been isn't gonna do anything but make you wonder why you tried that. if you try to redill the holes to match things up between the old and the new you will have made the frame weaker, if they don't quite line up, so the holes are oblong, the bolts will be under more stress to keep things from moving.
got pics of what you have there?

check the frame for straight and sag before you start anything. level side to side and block up all 4 corners. leave room to work. then do some checks.

http://chevy.oldcarmanualproject.com...51ctsm0202.htm

one of these assembly manuals should have a frame drawing with dimensions etc or you could ask on here if someone has the manual and they could send you a pic of the frame dimension page. that should have all the holes etc laid out for from a stock perspective.

http://www.classicindustries.com/pro...ts/tm1047.html

portworks 03-03-2020 11:33 AM

Re: HELP... 1951 3100 fr. Frame rail hole pics.
 
Yes they had attempted to convert a universal one deck did not finish. I will see if I can make it all work. Was hoping it would just be an easy lineup and bolt in deal.
That is never the case!

NeoJuice 03-03-2020 12:25 PM

Re: HELP... 1951 3100 fr. Frame rail hole pics.
 
Posting some pictures might show us what your working with.

dsraven 03-03-2020 06:46 PM

Re: HELP... 1951 3100 fr. Frame rail hole pics.
 
usually the cross member is marked down the middle at each end and that is the axle center line. you would line that up with the axle center line you want on the frame, then drill as required.

mr48chev 03-06-2020 01:24 AM

Re: HELP... 1951 3100 fr. Frame rail hole pics.
 
This is weld on but the centerline of the axle is still the same 18-1/8 inches back from the center of the hole that the spring shackle goes though.

Speedway instructions that are pretty detailed https://static.speedwaymotors.com/pdf/91044754.pdf



One thing. don't get stupid and remove those cast pieces that the spring shackles went though in the name of "cleaning up the frame horns. Those are what aligns the front bumper brackets right and if you remove them you have a heck of a time getting the bumper lined up right.

mr48chev 03-06-2020 01:29 AM

Re: HELP... 1951 3100 fr. Frame rail hole pics.
 
I wouldn't get too carried away worrying about old holes. just follow the instructions and go from there.


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