2D to PBS Sequential S4 upgrade on a 2006 Desert Dynamics

[JM PRO]

We are upgrading 2 cars in our group with PBS Sequentials this summer. They first car is 2006 4 seat Desert Dynamics Play car built by 3D. Stout car and has been flawless for the last 5-6 years since we have owned it. Engine was a 383 built stroker and the 2D was just not happy. With the Sequential going in, we are also installing a Magnuson M112 Supercharger on the 383 running 8 pounds of boost on the corn. We will get the car dyno'd and I will share results.

Here is the candidate:
2006 Desert Dynamics 4 seat Chromoly car finished by 3D
Upgraded 2" front hollows with RBP 4 piston brakes
RBP big rear micro stub kit
Rear trailing arms we built last year.
Torsion bar installed in rear of car.


Our goal is to install the Sequential, build custom fuel tank, install heat exchanger, relocate current radiator, build new rear cage.

 

[JM PRO]

Cutting most of the rear cage out since we are replacing cage. Tried using the front trans mount but I didn't like where the shift mechanism landed in relative to the inner pivot nut. So we moved the tranny 5/8" forward.

Our CV flange moved 1/2" higher and 3/8" further forward. Not ideal but that is what we got.

 

[Sutton]

Great looking car. I can’t wait to see updates and the new rear engine cage.

 

[JM PRO]

My first rendition using Bendtech

 

[JM PRO]

 

[J Alper]

Nice job, always wanted to get the software, is it pretty easy to use.

 

[Rockwood]

Cutting most of the rear cage out since we are replacing cage. Tried using the front trans mount but I didn't like where the shift mechanism landed in relative to the inner pivot nut. So we moved the tranny 5/8" forward.

Our CV flange moved 1/2" higher and 3/8" further forward. Not ideal but that is what we got.

View attachment 183447

Damn. When I saw the cut in the torsion bar, I was concerned. Now, less so.

Definitely something to watch.

View attachment 183457View attachment 183458

Where will the engine mounts end up? Hanging?

Buddy's DD with S4/6.0 (iron) cracked a bunch until we added triangles. It's a lot of weight hanging off the ass end and the cage flexes a lot.

 

[JM PRO]

Nice job, always wanted to get the software, is it pretty easy to use.

I have owned Bend-tech for 15+ years and have used it occasionally on projects. It has a pretty simply learning curve and is packed with features. After you build something, it will give you a cut sheet with length of each tube, locations to where the bend starts, how many degrees each bend is including spring back and will even do little print out sheets for the notching of each tube end.

 

[JM PRO]

Damn. When I saw the cut in the torsion bar, I was concerned. Now, less so.

Definitely something to watch.

Where will the engine mounts end up? Hanging?

Buddy's DD with S4/6.0 (iron) cracked a bunch until we added triangles. It's a lot of weight hanging off the ass end and the cage flexes a lot.

The car came with the hanging engine mounts and for the last 6 years has been flawless. No cracks and no signs of stress or fatigue. I am personally a fan of the idea of no lower engine mounts. I like the idea of not transferring the energy from a hard bottom out into the engine block. We tossed around the idea of going to traditional engine mounts but decided to stick with the hanging mounts.

 

[Reece Pettersen]

Can I ask why the PBS? I assume he got a great deal on it, but that's a lot of work for a trans that has unavailable parts.

 

[J Alper]

Can I ask why the PBS? I assume he got a great deal on it, but that's a lot of work for a trans that has unavailable parts.

Not sure why everyone is hating on a PBS, they are the same as a Mendi, also if you break a case you would have to replace a case, you would just replace it with a mendi,
the PBS is a little stronger and shorter than a S4, due to the way the gears stack inside,
and if a shift fork had a issue, we are working on make shift forks,

Damn. When I saw the cut in the torsion bar, I was concerned. Now, less so.

Definitely something to watch.

Where will the engine mounts end up? Hanging?

Buddy's DD with S4/6.0 (iron) cracked a bunch until we added triangles. It's a lot of weight hanging off the ass end and the cage flexes a lot.

So far we build so many DD car, just about ever DD car gets the torsion cut out for a S style trans even our car is cut,

Nice Work,

 

[Rockwood]

The car came with the hanging engine mounts and for the last 6 years has been flawless. No cracks and no signs of stress or fatigue. I am personally a fan of the idea of no lower engine mounts. I like the idea of not transferring the energy from a hard bottom out into the engine block. We tossed around the idea of going to traditional engine mounts but decided to stick with the hanging mounts.

Definitely recommend staying this way. Good work.

 

[JM PRO]

Can I ask why the PBS? I assume he got a great deal on it, but that's a lot of work for a trans that has unavailable parts.

You nailed it on the great deal. If he has to update to newest case, then we make the modifications. No biggie.

 

[Reece Pettersen]

Not sure why everyone is hating on a PBS, they are the same as a Mendi, also if you break a case you would have to replace a case, you would just replace it with a mendi,
the PBS is a little stronger and shorter than a S4, due to the way the gears stack inside,
and if a shift fork had a issue, we are working on make shift forks,

So far we build so many DD car, just about ever DD car gets the torsion cut out for a S style trans even our car is cut,

Nice Work,

I had a PBS and didn't have any issues, not hating on it. Good to know you are working on shift forks. To my knowledge, that and the case are the only items currently unavailable.

 

[JM PRO]

Tight fit!

 

[JM PRO]

As you can see in the last pic, the face of the trailing arm tabs have severe wear. The outer tab I am going to cut off and replace with a new tab. The inner tab is integrated to the torsion housing and the 1.5" tube running below. My game plan is to grind down the high spots on the face then JB Weld a .030" heat treated shim into place. I will then tack weld the shim into place in a couple locations just for the added measure in case the JB Weld doesn't hold and the shim wants to rotate with the arm.

I've done this once before with good results. All ears if someone has done something different that has proven to work.

Thanks

 

[ranman5608]

with hanging engine mounts I recommend putting a few gussets on the transaxle tabs I had an issue with my motor and transaxle "swinging" forward about an 1/8th of an inch on a big ass slapper g out that bent the rear removable section of the frame. I wound up boxing the rear mount and adding triangle gussets to the front mount. I also added some triangulated structure around the motor and gearbox I was worried that if i hit the back of the car it would have bent up the removable back end again, also if the upper hanger mounts are not in the node for the back end of the frame and pushed rearward like mine are i would recommend adding a gusset tube to help that area as well, as shown in the red highlights in the last picture.