rigid rear end: pics and tech, please

[sgtlethargic]

Please post pics and tech info on rigidly mounted rear ends. I don't know what I'm doing- I need ideas. Once I get some ideas I can run with it. I vaguely remember some pictures (years ago) of a part Aussie guys had for this.

Thanks,
Kurt

[Old6rodder]

Howdy Kurt,

Here's ours. I just cut out the plates, drilled and bolted'em to the rails and set'em on the axle loose. Then I centered it, squared it and lined it up with the engine/gearbox and welded it up right there. Let it cool, unbolted it and welded the insides.

NHRA likes to see three 1/2" grade 8 bolts per side, of course that rule's for blown fuel slingshots. But, whatever, it keeps'em happy ........

Later I decided to weld a piece of 3/8" rod along the underside of the axle tube at each plate location to straighten it out again. The top side only welds had tweaked it up slightly when they'd cooled (not enough to be an actual problem but enough to annoy a pattern makers mind :rolleyes:).

http://farm5.static.flickr.com/4002/4523846493_2fa7e1f541.jpg

http://farm5.static.flickr.com/4027/4524476988_7b1eb04a19.jpg

[bobw]

http://i256.photobucket.com/albums/hh179/rwstillwater/2009_0118trk0002.jpg
Pretty much the same as Dick's. 1/4" plate. I later added a 3rd bolt and drilled some 1 1/2" holes to lighten the plates. Since I bolted through the rectangular tubing it was necessary to add sleeves to maintain rigidity.

[bobw]

http://i256.photobucket.com/albums/hh179/rwstillwater/2009_0118trk0001.jpg
See the sleeves. The measurement, alignment and welding procedure matches what Dick did. I haven't detected any axle housing warpage. But it is a 9" Ford which is pretty heavy.

[CrkInsp]

A couple of pics of the way the "Senile ole Men" attached the rear axle in there car. There is also an anti rotation bar attached to the pinion snout.

[Katuna]

In resarching our build this was one of my questions. Here's a couple of pics. Can't recall who's rides off hand. Thought I had more.

[Drewfus]

mine....overkill, but I like it like that...;):D

http://img.photobucket.com/albums/v316/DrewfusDesigns/HAGR/200109016.jpg

http://img.photobucket.com/albums/v316/DrewfusDesigns/HAGR/021007chassisrepaint2.jpg

and QQMOONs

http://img.photobucket.com/albums/v316/DrewfusDesigns/HAGR/NET271106045.jpg

Cheers,

Drewfus:)

[CrkInsp]

Pic 2 in post 6 appears to be the car of Don Alexander, Coweta, OK. The brackets were made by Bob Hindman, Broken Arrow, OK.

[Rand Man]

Bob had offered those brackets (cheap to free?) to anyone building an HA/GR. I don't know if that deal still stands, but they are excellent brackets.

[REJ]

The blue car in post #6 is mine.
I cut the brackets out of 5/16" plate and they have worked fine for three years.
I do not run any NHRA tracks and have only four 1/2" bolts in my rear end. I guess I could add another, but why?
Robert

[Joe Hamby]

Hi Robert, you raise a good question. When I think about it, it one breaks you can have movement. With a third in there it should not move. But that is only bench racing and engineering. Joe

[REJ]

When I first built the car, NHRA required two 1/2" bolts per side. What changed?
Did they have several accidents because of the two bolts per side rule?
This is one reason that I am sick of NHRA's BS.
I have talked to several guys that run FED's that have been around longer than me. I am beginning to agree with what they have to say about NHRA. They have people setting the rules and regulations that have no idea about safety, they are mechanical engineers that have landed a job with NHRA.
And unfortunately I work with mechanical engineers every day that have no common sense and do some of the most outlandish things that do not work and will not ever work. It looks good on paper, but for some reason when it is built, it does not perform like they thought it would.
I am not going to get in a car that I think is unsafe and drive it down the track. But I believe that common sense will prevail over some of the BS that NHRA puts out and changes every year.
Just my opinion, Robert.

[Katuna]

Don't get me started on engineers. That explains ALOT about NHRA!

[ScottV]

Don't get me started on engineers.

But without them, who would drive the trains ??? :p

[Toymaker]

I like to keep it simple, and didn't wqanty to take the time to bolt the rear end in :D
http://i472.photobucket.com/albums/rr84/Toymaker1/HAGR44.jpg

[hotrodbob]

I like to keep it simple, and didn't wqanty to take the time to bolt the rear end in :D
http://i472.photobucket.com/albums/rr84/Toymaker1/HAGR44.jpg

Looks good, but thought we couldn't run an automatic?

[greasel]

Looks good, but thought we couldn't run an automatic?

Technically not for the HA/GR class. Many of these also run ANRA or just whatever at the local drag strip. We're spacing our engine far enough forward that we can fit an auto in if we ever want to do that in the future just to see how fast we can run.

[Old6rodder]

Rocky and Lee ran that slushpump the first season while they scouted out a (harder to find) gearbox for their car. In that their slushpump was only stock they ran better with the gearbox once they got it in.

Lee also commented on the extra degree of fun it was tossing gears rather than just holding the wheel, a tenet of the class in the first place. :cool:

Rather like Dick M. running radials for now. It's what he had on hand for the build and easy enough to fix when he gets 'round tuit.

[hotrodbob]

Okee Dokee, ANRA has more races close to me so that is an option... Thanks

[OBFB HA/GR]

I had to add the "anti rotational device" as used in an 'A/Modified dragster , so I could pass ANDRA Tech . The Tech inspector says the 1/8" sandwich plates and the 4 grade 8 bolts each side were not enough , so when the "family jewels" are at stake I kind of agree.
1/8 plate welded around axle housing bolted to 1/8 plate welded to the frame rail edges and crush tubes thru the sandwich

[CrkInsp]

The "Senile Ole Men" ask me to post these two pics of there car (rear end mounts). They thought the pics in #5 were not good enough to show how the rear end is secured (bolted) with the anti rotation bracket with a total of 15 bolts holding the axle housing.

[ScottV]

They may be senile, but man they do good work ... I wonder if they know that ???!!!??? :p

[hotrodbob]

Looks real good