[Shan]

Hi guys,

I have searched the forums for a definitive answer, but just wanted confirmation I have the right of it.

I am considering a wider rear wheel option for my Camaro project. Obviously I understand mini-tubs can provide the clearances I would need to run a 10"+ tyre.

In australia, notching or cutting frame rails is a bit of a "no, no". There are a lot of hoops to jump through, and engineering approvals required, before you can legally drive a vehicle with structural modifications on the road here. Also costs a lot of money to get these approvals.

DSE tubs seem to be the clear choice, but I can see you need to notch the frame a little to install them. ideally I would like to avoid this for the previously mentioned reasons.

I have also seen other comments about people moving the tub back to the rail, gaining some clearances and essentially fabricating a panel to fill the gap. This mod does not cut the frame and provides some extra clearance for a 10" wheel.

Do I have that right???

Can the wheel tub width be increased to accommodate a 10" wheel without messing with the frame?

Says something like that here:
https://www.camaros.net/forums/56-pro-touring/366937-mini-tub-without-cutting-frame.html

For the record I have the Ridetech 4-link installed, so got all that covered from the suspension side of things.

I would be happy enough running a 10" wide that did not rub on anything - that would honestly be plenty for me. I am not greedy with my wheel rubber like some others ; )

What are my options?

Cheers,
Shan

 

[pittpens24]

Your theory is correct. One thing that might be a little easier than making a gap panel would be to buy steel wheel tubs and cut them accordingly if you weren't keeping the stock look. Since they are flat backed, they would tuck up nicely to the frame rail.
http://www.shopcompetitionengineering.com/ceb/web/images/C3006_part.jpg

 

[dhutton]

Dynacorn has DSE style minitubs that are slightly narrower and do not require notching of the frame rails. I think AMD sells them too.

Don

 

[DOUG G]

8" fit in stock tubs, so a 2" mini tub should fit 10" wheels without issue....and no messing with frame rails.

https://www.ebay.com/itm/DSE-Mini-T...h=item520c24576d:g:9G4AAOSwNDZbM8ta:rk:4:pf:0

 

[dhutton]

8" fit in stock tubs, so a 2" mini tub should fit 10" wheels without issue....and no messing with frame rails.

https://www.ebay.com/itm/DSE-Mini-T...h=item520c24576d:g:9G4AAOSwNDZbM8ta:rk:4:pf:0

DSE minitubs require frame rail mods, hence the additional pieces in the auction you posted. Dynacorn minitubs do not require frame rails mods....

Don

 

[DOUG G]

DSE minitubs require frame rail mods, hence the additional pieces in the auction you posted. Dynacorn minitubs do not require frame rails mods....

Don

I stand corrected....thank you :beers:

 

[tp_smith]

I bought a set of one piece Dynacorn wide mini tubs. The are 15.25 inches wide. They are 2.25 inches wider than stock. I had to notch the frame rails.

 

[dhutton]

I bought a set of one piece Dynacorn wide mini tubs. The are 15.25 inches wide. They are 2.25 inches wider than stock. I had to notch the frame rails.

You must have got a special extra wide set :grin2: This clearly states no frame rail mods needed for Dynacorn inner minitubs:

https://www.ebay.com/itm/68-69-F-Bo...Camaro&hash=item4d2f644820:g:AUgAAOSw9N1Vw5i4

Don

 

[tp_smith]

You must have got a special extra wide set :grin2: This clearly states no frame rail mods needed for Dynacorn inner minitubs:

https://www.ebay.com/itm/68-69-F-Bo...Camaro&hash=item4d2f644820:g:AUgAAOSw9N1Vw5i4

Don

Maybe. The Dynacorn website does not make the same claim as the Ebay vendor. I was able to fit an 11 inch wide rim with a 315/30/r18 tire. I could have fit a 335 mm tire, but my rim was too narrow. My car is a 1969 Firebird. I thought the Firebird would be the same as a Camaro. I could be wrong.

Here is a link to the installation of my Dynacorn tubs. Post #56

https://www.camaros.net/forums/133-build-projects/436193-1969-firebird-convertible-photos-4.html

 

[dhutton]

Maybe. The Dynacorn website does not make the same claim as the Ebay vendor. I was able to fit an 11 inch wide rim with a 315/30/r18 tire. I could have fit a 335 mm tire, but my rim was too narrow. My car is a 1969 Firebird. I thought the Firebird would be the same as a Camaro. I could be wrong.

Here is a link to the installation of my Dynacorn tubs. Post #56

https://www.camaros.net/forums/133-build-projects/436193-1969-firebird-convertible-photos-4.html

69 Firebird and Camaro are the same.

Don

 

[3d cad]

Having gone down the mini tub path i think desribing whats under there as a frame is a stretch.....

 

[rodent4]

OP, If you install DSE mini tubs and don't tell anyone, how would they know

You would have to have in intimate knowledge of these rides, and I'm quite sure most of the basic units out here who might take a look at your ride would never know.

 

[schnide]

Having done a 2" mini tub, just get the Dynacorn tubs and massage them where they meet the frame rails so you don't have to notch the rails.

 

[Shan]

Seems to be some mixed messages in this.....

I have been reading around.....various forums. Some people are saying Dynacorn is wider than DSE, others think otherwise.

So we have:

DSE Tubs
Dynacorn Tub
Goodmark Tubs

So I have been doing a little research.....

DYNACORN:
I also notice on Camaro central - they advertise the following:
https://www.camarocentral.com/1969_Camaro_Complete_Wheel_Well_Housing_2_Wider_p/she-516wa.htm
***Note they mention frame rails also need to be modded on this 2" tub option.

Although the specs and dimensions closely resemble this:
http://www.dynacorn.com/ShowItem.aspx?item=1041FD
Images looked like they were pulled from the Dynacorn site, so if that is right - camaro central are saying frame rails need to be altered for the Dynacorn unit.

DSE:
We know the DSE tubs definitely require notching

GOODMARK:
https://www.goodmarkindustries.com/p-18285-wheelhouse-inner-lh-68-69-f-17-h-x-34-l-4020-670-68l.aspx
**Seems to indicate that it is 2 1/4" wider tub.

So if the description is accurate - you would think the goodmark unit is WIDER than the Dynacorn unit??

So out of the 3, would seem the Dynacorn unit is the smallest offering, but if you believe what some websites state, that also need notching of the frame rails.

Other comments here infer the 2" can be muscled and finessed to work without modifying the rails??

Is that the consensus?

Others mention cutting and moving the existing tub back to the chassis and creating a filler panel to close the gap.

That could work, but would be less fabrication in buying a wider tub that simply fits.....be good to get the 100% confirmed.

Can anyone add any final comments on this subject to close it out?

To be honest - I am still a little confused as to the best option to widen WITHOUT touching rails.

....And to comment on the other post about doing it anyway...our engineers in australia KNOW when you do stuff. These engineers have seen guys trying to dodge the rules to get cars on roads for years....they are all over it. Do it right and do it legal.....with their approval. Otherwise all sorts of headaches will follow. So need to do this without notching the rails....

 

[dhutton]

Seems to be some mixed messages in this.....

I have been reading around.....various forums. Some people are saying Dynacorn is wider than DSE, others think otherwise.

So we have:

DSE Tubs
Dynacorn Tub
Goodmark Tubs

So I have been doing a little research.....

DYNACORN:
I also notice on Camaro central - they advertise the following:
https://www.camarocentral.com/1969_Camaro_Complete_Wheel_Well_Housing_2_Wider_p/she-516wa.htm
***Note they mention frame rails also need to be modded on this 2" tub option.

Although the specs and dimensions closely resemble this:
http://www.dynacorn.com/ShowItem.aspx?item=1041FD
Images looked like they were pulled from the Dynacorn site, so if that is right - camaro central are saying frame rails need to be altered for the Dynacorn unit.

DSE:
We know the DSE tubs definitely require notching

GOODMARK:
https://www.goodmarkindustries.com/p-18285-wheelhouse-inner-lh-68-69-f-17-h-x-34-l-4020-670-68l.aspx
**Seems to indicate that it is 2 1/4" wider tub.

So if the description is accurate - you would think the goodmark unit is WIDER than the Dynacorn unit??

So out of the 3, would seem the Dynacorn unit is the smallest offering, but if you believe what some websites state, that also need notching of the frame rails.

Other comments here infer the 2" can be muscled and finessed to work without modifying the rails??

Is that the consensus?

Others mention cutting and moving the existing tub back to the chassis and creating a filler panel to close the gap.

That could work, but would be less fabrication in buying a wider tub that simply fits.....be good to get the 100% confirmed.

Can anyone add any final comments on this subject to close it out?

To be honest - I am still a little confused as to the best option to widen WITHOUT touching rails.

....And to comment on the other post about doing it anyway...our engineers in australia KNOW when you do stuff. These engineers have seen guys trying to dodge the rules to get cars on roads for years....they are all over it. Do it right and do it legal.....with their approval. Otherwise all sorts of headaches will follow. So need to do this without notching the rails....

What will the engineers say when you relocate your shocks?

Don

 

[Shan]

Fair question....

Guidelines here for modified vehicles in Australia are COMPLEX to say the least.

Each engineer authorized for certification of the modified vehicles applies their own understanding to these guidelines. Which makes it tricky. Everyone has s different opinion.

Majority are ok with triangulated 4link, although some testing and materials approval is often involved.

For some reason engineers dislike frame modification discussions. You are then looking at all sorts of stress analysis, likely CAD FEA testing.....potential chassis flex testing. Gets crazy.

And yes - does not make sense I know. I do not make the approval rules here....wish I did. Oz is very different to USA in this regard.

If I can extend without chassis mod - will be a LOT easier.

Just need to select the easiest path.

 

[tp_smith]

The DSE tubs come with extra parts to cover the frame rail that has been notched. You would be buying extra patch metal that you won't need.

I know the Dynacorn does not come with the pieces that covers the frame rail notches. Perhaps Goodmark is the same.

I would buy either the Dynacorn or Goodmark tub. The price and shipping would be an important factor.

I would cut the center flange off the new tub and fit the tub inside the car. Then I would mark a long line where the excess metal overlays the outer wheel house. Take the tub out of the car and bend a new flange using the line as the bend vertex. The modification would be invisible.

Cutting the tub in the middle and adding a strip of sheet metal would require two seams that need to be butt welded together. That would be a lot of welding and grinding to make the seams go away.

The center flange that I am talking about is shown in the photo below. The upper half is the inner tub. The flange is the part that has many shiny circles that are cut spot welds.

mini tub 7 by Patrick Smith, on Flickr

Mr. Dutton makes a good point about the shock tower. The 1969 model stock shock position is very close to the factory tub. Another point is the actual frame rail. It has a flange on the frame rail that is bent outwards. The frame rail flange is very close at the rear of the existing tub.

If you are planning to change the rear suspension, there are vendors that provide the suspension upgrades that includes new frame rails that will accept wider tires. The suspension vendors might be able to provide the necessary documentation required by the inspectors. Art Morrison is one that comes to mind.

Art Morrison Enterprises - Camaro Information

 

[Shan]

I actually purchased the ridetech 4-link some time ago. Was not thinking about widened tubs at the time unfortunately.

So my path is fixed in that regard.

I purchased the: https://www.ridetech.com/applications/musclecars/1967-1969-chevy-camaro-firebird-airbar/

So I gotta make all this work somehow.

Thanks for the advice guys. Will think on the matter.

 

[schnide]

I was always told that both Goodmark and Dynacorn come from the same stamping supplier. I've actually seen boxes at Carlisle with both labels on them. Makes me wonder if the tubs aren't the same...

BTW, you realize you will have to modify the rear seats to fit around the new tubs. It's no big deal, but needs done even with a 2" mini tub.

 

[Shan]

Interesting.

Wonder if the Goodmark and Dynacorn are the same then? Beginning to sound like they could be?

Other info on websites says one is 2" and the other 2 1/4. Would be great if that could be clarified by someone?

Rear seats - yeah - had read they need to be tweaked. I currently have all the interior out and have the TMI Sport R for the front and rear seats to go in. I am getting that done by a shop, so ideally prefer to tub the rears now so they can accommodate for the changes in the install.