PACE 427 Unveiled

[sambo]

I love the stance with the 100mm ride height Craig, plus the wheel sizes/offsets look great. I haven't seen those wheels before, who are they made by?

One question about all that beautiful aluminium work. I have an al. fuel tank which dulls very quickly, being exposed to road grime etc. Do you use any sealants or treatments to prevent or slow the onset of corrosion? I can see all that latticework in the engine bay being a pain to polish. Also with regards to physical stress, what has been done to prevent cracking over time? We know this was a problem with the original Cobra bodies.

[400TT]

Sambo, the wheels are Vintage brand, just BRM(GT40) style instead of Halibrand. We have a few Cobra guys going with that style due to the timeless appeal of spoked centre design it features.

With the alloy material, total different grade of alloy than what your tank is made of and features superior corrosion resistance etc. But in saying that, for the show type of guys, we have great success with the cleaning and protective wipe on finishes like Shark Hide etc. They just leave a very clean bright aluminium look that is protected from stains and you can't tell the treatment is on there. Easily re-applied if required.

We have analysed the stress areas of the chassis using FEA and measured the stress using Safety Factor of the material and welds, Von Mises etc. Basically we have tortured this chassis design using simulations on the computer over and over with different scenarios. Same with intrusion bars, mount points, suspension pieces, brackets, you name it. We know the simulations are accurate as we can predict the outcome of a physical street registration chasis torsional test for example within a few percent. All stress areas have stronger design incorporated i.e. gusseted and/or heavier material used. This is obvious when you see the chassis in the flesh.

Weld quality is a critical element and we utilise a top of the range Miller Dynasty 350 Watercooled Pulse TIG machine with all the extras(fingertip control etc), correct filler rod and an expert welder etc.

We also have a much stiffer chassis construction and I would say a much more consistant twist and flexure compared to other chassis designs out there. A lot of hours, expertise and expert tools have been used to design an efficient and reliable chassis structure. Of all the chassis I have seen tested, our PACE 427 design has much, much better consistancy. The numbers are publicly available for comparison.

We have also needed to get our own custom extrusions manufactued as there was not extrusions available in the grades of alloy we were looking for.

Won't even comment on the quality of the original Cobra bodies, give me a Kirkham body any day. Same approach, you won't see any issues with Kirkham bodies, quality approach to materials and construction used. We are not supplying 60's quality products.

And the great thing about an aluminium semi-monocoque chassis is that it makes it very easy, clean and efficient to construct into a vehicle as the heavy wall aluminium is a breeze to drill and tap and it is everywhere, even the panels can be drilled and tapped.

I am happy for any scrutiny. I can't stress enough that we have left no stone unturned.

We are still waiting for some of our production parts to arrive for the first batch of 10+ kits, so some aspects will look and work different once the final production parts are available.

Hope that has answered the questions. Did I miss anything?

[Dazza70]

Originally Posted by 400TT

Sambo, the wheels are Vintage brand, just BRM(GT40) style instead of Halibrand. We have a few Cobra guys going with that style due to the timeless appeal of spoked centre design it features.

With the alloy material, total different grade of alloy than what your tank is made of and features superior corrosion resistance etc. But in saying that, for the show type of guys, we have great success with the cleaning and protective wipe on finishes like Shark Hide etc. They just leave a very clean bright aluminium look that is protected from stains and you can't tell the treatment is on there. Easily re-applied if required.

We have analysed the stress areas of the chassis using FEA and measured the stress using Safety Factor of the material and welds, Von Mises etc. Basically we have tortured this chassis design using simulations on the computer over and over with different scenarios. Same with intrusion bars, mount points, suspension pieces, brackets, you name it. We know the simulations are accurate as we can predict the outcome of a physical street registration chasis torsional test for example within a few percent. All stress areas have stronger design incorporated i.e. gusseted and/or heavier material used. This is obvious when you see the chassis in the flesh.

Weld quality is a critical element and we utilise a top of the range Miller Dynasty 350 Watercooled Pulse TIG machine with all the extras(fingertip control etc), correct filler rod and an expert welder etc.

We also have a much stiffer chassis construction and I would say a much more consistant twist and flexure compared to other chassis designs out there. A lot of hours, expertise and expert tools have been used to design an efficient and reliable chassis structure. Of all the chassis I have seen tested, our PACE 427 design has much, much better consistancy. The numbers are publicly available for comparison.

We have also needed to get our own custom extrusions manufactued as there was not extrusions available in the grades of alloy we were looking for.

Won't even comment on the quality of the original Cobra bodies, give me a Kirkham body any day. Same approach, you won't see any issues with Kirkham bodies, quality approach to materials and construction used. We are not supplying 60's quality products.

And the great thing about an aluminium semi-monocoque chassis is that it makes it very easy, clean and efficient to construct into a vehicle as the heavy wall aluminium is a breeze to drill and tap and it is everywhere, even the panels can be drilled and tapped.

I am happy for any scrutiny. I can't stress enough that we have left no stone unturned.

We are still waiting for some of our production parts to arrive for the first batch of 10+ kits, so some aspects will look and work different once the final production parts are available.

Hope that has answered the questions. Did I miss anything?

Hi Craig,

Firstly I must say that you've turned engineering into an art form with your Pace 427 Chassis and I'm extremely impressed!! I have been a little shy of the thought of aluminium construction chassis due to the material's nature of (work hardening) fatigue and cracking from stresses but by the sounds of it you've put a hell of a lot of thought and engineering into the design and manufacturing to counteract this from happening!

Please forgive me for my ignorance as I'm not really familiar with the Push-Rod Suspension set-up; would a sway (or anti-roll) bar enhance the handling of this type of setup or would the addition of one be considered as of no real significance?

Hopefully in a year's time I'll be ready to place an order for a Comprehensive Kit as I'm blown away with the quality and quantity of the parts supplied in this kit!!!

Congrats on what looks like one hell of a Cobra Kit!!!

Cheers,

Daz

[400TT]

Daz, no issues at all with reliability with our chassis. High quality product from design, material types, weld quality etc.

Still use Sway bars for the track orientated cars. Cool thing by utilising pushrod suspension is that the sway bar links just need to connect to the inside of the bellcranks. So a very short, simple and lighter weight sway bar setup needed.

We also have the ability to adjust the push rod suspension design to operate as a rising compression rate. It would just be a bolt on change.

Thee whole suspension design is based on the fundamental principal of bolt on changes, you can change virtually any aspect of the suspension geometry, ride height, anti-drive, anti-squat etc. with just different mounting brackets.