Sterndotstern

Hit a berm with the left rear wheel a couple weeks ago racing at Firebird Main (now I hate it even more) and this is what it did:





Is there any hope of salvaging this chassis? Or is it time to start parting out?

-- Jon

Tyson

you can buy and weld in a new subframe.

why dont they fill that ditch up with quickrete???

thawley

Na, just wire wheel it a little and weld the sumbitch back together...

Sterndotstern

Kickass. Thanks for the advice guys. That makes me feel about $3000 better about it.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tyson &raquo;</TD></TR><TR><TD CLASS="quote">
why dont they fill that ditch up with quickrete???</TD></TR></TABLE>

I'm not sure, but after this, I might just sneak out there next weekend and do it for them.

Found another moderately-oversized pic showing the EXACT MOMENT I did this:


It doesn't look so bad from 100 yds away... but it's the same berm that ate Chads and Bernardo's wheels that weekend.

Again, thanks for the advice guys.

Tyson

ah yeah, that car. like i told you, that chassis has been used more than rj's mom. im not surprised it cracked at the subframe either.

Sterndotstern

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tyson &raquo;</TD></TR><TR><TD CLASS="quote">ah yeah, that car. like i told you, that chassis has been used more than rj's mom. im not surprised it cracked at the subframe either.</TD></TR></TABLE>

Honestly, after what you told me, I wasn't that surprised either. However, if I were planning on replacing the chassis it would have been nice to know about this before I spent $300 cleaning up the cracked right side door area...

I'm talking to our local Honda service shop right now, they don't seem to have any idea what the subframe there is... Good thing I've got pics!

-- Jon

Tyson

#33
http://www.slhondaparts.com/br...FLOOR

Sterndotstern

Nice, that's a handy online parts catalog. I just got off the phone with Precision, our local Honda shop, and they've got one on the way for $160.

Won't be here quite in time for the weekend, but that'll give me some time to get the suspension off. Thanks Tyson!

-- Jon

AndyHope

I had a similar failure on my CRX. I bought a new replacement rear subframe (was told it was the last one in the country) a couple years ago.
I took it to my friend's shop (Eastside Muffler) and we decided that it would be easier to just weld the old one back together than to try to drill it out and weld the new one back it the right place. We also cut out some gussets to reinforce the parts that had cracked.

Seemed to work just fine after that.

I had to go through a whole race at Willow with the bad subframe. Active toe and camber is no fun at 125mph.

Sterndotstern

That is SUPER interesting, Andy, because my shop called me back and told me that some jerk named "Handy Ope" had aquired the very last rear subframe crossmember in the country.

Actually, they told me to try to find a U-Pull-It because they won't be able to get me the part. I guess I should go back out there with the camera to get your fully-informed opinion, there's other damage to the X-member closer to the suspension pickups that worries me -- obvious metal fatigue. That might have been there the whole time and not be a cause for worry, or...

Anyway, thanks for the input. You wouldn't happen to have that old X-member clogging up a shed somewhere, would you?

-- Jon

WWDTrackRacer

Wondering if squirting that thing full of foam stiffener stuff would help
prevent it from cracking? What do you guys think?

CRX Lee

If anyone has any suggestions on repairing or strengthening this rear subframe, I would be interested in seeing it. Although I have never had any trouble in any of my cars (knock wood), I keep wondering about the rear of my FP car since it is running 9.50 inch wide racing slicks and can generate some serious side bite. I have considered welding some support bars from the area of the LCA bolt holes to about the center of the subframe as basic triangulation to help add support but if the actual welds from the shell to the subframe are failing then this is not going to help much except for spreading the load a bit farther.

I have very little interest in the blingy heim ended bars that go side to side between LCA bolts because they will add less support to the chassis than my simpler and cheaper idea. I have seen the big plates that people have made to mount big sway bars on but that is of no interest for me either as it looks heavy and likely less supportive for my needs than my simple idea.

chad

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sterndotstern &raquo;</TD></TR><TR><TD CLASS="quote">

It doesn't look so bad from 100 yds away... but it's the same berm that ate Chads and Bernardo's wheels that weekend.

Again, thanks for the advice guys.</TD></TR></TABLE>


yes same HOE...i mean HOLE....grrrrrr....i need to invest in that hole...could make me some money....betting on it!

Honda318dx

Post this in the Welding forum and see what kind of reponse you get..

Sterndotstern

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Honda318dx &raquo;</TD></TR><TR><TD CLASS="quote">Post this in the Welding forum and see what kind of reponse you get..</TD></TR></TABLE>

Done and done. For the curious:
https://honda-tech.com/zerothread?id=1484456

trigun7469

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thawley &raquo;</TD></TR><TR><TD CLASS="quote">Na, just wire wheel it a little and weld the sumbitch back together...</TD></TR></TABLE>

if you can replace it i have actually had this happen twice to me, welding it back together broke other parts. Theres a rear sway bar that actually bolts to the the subframe so you may want to invest in that and welding a brand new subframe. Thats really odd that it happened in the same place as my car, the only difference was my car was a 90 civic si.

AndyHope

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Sterndotstern &raquo;</TD></TR><TR><TD CLASS="quote">
Actually, they told me to try to find a U-Pull-It because they won't be able to get me the part. I guess I should go back out there with the camera to get your fully-informed opinion, there's other damage to the X-member closer to the suspension pickups that worries me -- obvious metal fatigue. That might have been there the whole time and not be a cause for worry, or...
Anyway, thanks for the input. You wouldn't happen to have that old X-member clogging up a shed somewhere, would you?
-- Jon</TD></TR></TABLE>

Mine was really bad. Both sides of the subframe had separated from the chassis. The only spot welds left were the ones in the center. I could have replaced it but we weren't sure how to get the new one in exactly the right place. Mine also had severe tears out on the ends near that seam.
Sorry, I don't know what happened to the new one. If I find it I may get it gold plated though.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by CRX Lee &raquo;</TD></TR><TR><TD CLASS="quote">If anyone has any suggestions on repairing or strengthening this rear subframe, I would be interested in seeing it. Although I have never had any trouble in any of my cars (knock wood), I keep wondering about the rear of my FP car since it is running 9.50 inch wide racing slicks and can generate some serious side bite. I have considered welding some support bars from the area of the LCA bolt holes to about the center of the subframe as basic triangulation to help add support but if the actual welds from the shell to the subframe are failing then this is not going to help much except for spreading the load a bit farther.

I have very little interest in the blingy heim ended bars that go side to side between LCA bolts because they will add less support to the chassis than my simpler and cheaper idea. I have seen the big plates that people have made to mount big sway bars on but that is of no interest for me either as it looks heavy and likely less supportive for my needs than my simple idea.</TD></TR></TABLE>

We started by welding all the cracks back together. Then seam stitched the subframe back to the chassis. Then we added another layer of steel over all the spots that had cracked. (my worst tears were up higher than Jon's, above the LCA bolts) Then we made big gussets that triple walled that area. We did not reinforce the area in between the LCA's where Jon's broke. I run one of those bolt in bars back there and I guess it was working.

I wouldn't be too concerned with adding weight to that area. It's probably the best place on the car to be carrying around extra weight.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chad &raquo;</TD></TR><TR><TD CLASS="quote">yes same HOE...i mean HOLE....grrrrrr....i need to invest in that hole...could make me some money....betting on it!</TD></TR></TABLE>

That hoe is a real beyatch! fo shonay. I don't think you're pimp enough to make money off her. She might bend a corner with you though.

AdamITR

When our Civic EG hit the infield wall at Lowes Motor Speedway, the subframe was bent, and slightly buckled at about the same location. We put the car on a Frame Rack, pulled it straight, and then welded plates around the entire area. Worked fine.

In your case, I would probably just order a new subframe, than try to fix that though.

jisu009

or just replace the chassis.

hint hint

Kamin

omg i hate that god damn corner. firebird needs to get off their cheap asses and pave the inside of it. so much damage is caused there...

but what i would do is weld it back together, then fit a bigger plate over it and weld the plate down. theres no way all of those welds would fail

ITAcelica

Did that to my Toyota Supra. I took it to the muffler shop and got it welded back up for $75. I use to drag race it. But I think a good body shop can do a better job then a muffler shop. You need to find a shop that has a good welder and a welding machine that can do the job.

Sterndotstern

Bringing this back for a couple last questions. I'm decided -- I'm going to try to repair the thing instead of replacing it. If any fabricator-types want to invest some knowledge with me, I have a few questions.


1) How would you reinforce the part?

2) What's a rosette weld?

3) Are there any "gotcha's" I should watch out for in stitch welding it to the unibody?

Any advice , pictures, drawings or common sense is much appreciated.

--Jon

prkiller

1) How would you reinforce the part?
I personally would weld a piece on the inside of the subframe with rosette welds, then weld the piece back in as best you can exactly where it was located. Next is weld that inside piece to the broken piece you just put back in. Then weld the 2 broken pieces together. Then rosette weld another piece over the broken parts and maybe stitch weld that extra piece as well.
Not sure if this makes sense because it's late, but hopefully it does...

2) What's a rosette weld?
Basically, it's when you drill a hole on the top piece you are welding, set it over the other piece, and weld up the hole!
You can see the "spot welds" in that pic below.. Those are rosette welds...



3) Are there any "gotcha's" I should watch out for in stitch welding it to the unibody?
Just don't burn through the unibody. Everything on the CRX seems pretty thin, and any heat just seems to burns right through it. Go slow, and try not to weld long on any section. Move around a bit on the thin stuff...

Louie B.

Kind of a random question, but do you guys think having a rear lower strut tie brace could have helped the situation, made it worse, or had no effect?

Tom Blaney

I think the rear lower strut brace (like the one I sell (shameless plug)) would have limited the damage, but a hole like that would have still created some damage.

The strut brace will do a lot to keep the crossmember intact, but unless there were a lot of stress cracks (not uncommon and I have braced two of them) on the crossmember that was a serious shot.

When I have repaired them, I bought a replacement crossmember from a aftermarket fender supplier, cut it so that it would fit over the existing piece (cut off the spot welding flanges and about an 1/2" from the bottom rail to split it in half. You want to try and make a sandwich out of it, and then weld the new piece on top of the existing crossmember. I used a lot of stripper and thinner to get all of the undercoat off so that it could be welded cleanly.

The crossbrace will help in the future (or to a undamaged car) to keep the chassis stiffer and to helped (some) from the kind of cracking that normally occurs there.

Tom Blaney