Butler Cobra with Mustang II IFS

[Tom Howland]

cdcofer, thanks for the kind words. My front clip was built to slide into the existing frame rails.

Just to the left of the oil pan is the new joint of the old level frame and the new angled frame.


I inverted this picture so you can see the frame in the correct position. The level pieces to the left slide into the old frame. The radiator sits between the wide level pieces to the right.


Arthur, I was never happy with the MGB suspension. The new suspension performs 100% better. Rat_rod_Russell has done a better job of fabing the a-arms to the frame. He put them at the correct front to rear angle where as mine are level. That angle would change the castor with wheel rise and fall. I don't know what difference that would make.

[decooney]

Arthur, Tom,
If either of you run across a decent rod/custom shop in California who's experienced, available, reasonably priced, and willing to do a Mustang II or C4 front-end changeover on another Arntz/MGB front end on a Cobra, please let me know so I can pass it along to a friend looking to do same type conversion on his Cobra. I wish I could help him but just don't have the time, so I thought I'd put a post here for him on CC just in case someone comes to mind.

[lal Naja]

cdcofer, Thanks for the status report on your Cobra and the links. I'm leaning towards the Mustang II as there are tons of after-market Mustang II components available at reasonable prices + you can buy upgrades like: larger brake rotors, multi piston calipers, etc. etc.

Tom, Great job on your IFS. Did the track width change? Any problem with connecting the steering column?
FYI the angle mounting of the upper wishbone is for Anti-Dive characteristics. The angle is about 3 + - degrees higher in the front. It prevents the nose from diving down under hard braking forces. The engineering on anti-dive is complex and involves vector force calculations. And it seems that the 3 degree incline does the trick.

Duane, I don't know of anyone who has done a Mustang II for the Butler Cobra. I'm here on the Forum looking for that. Unique Cobra has a system ($3,230.00) that they say should bolt up to the Butler and I understand that the design/geometry is based on the original AC Cobra. I don't know if Unique takes into consideration the bottom radiator hose of the Butler, but I'm sure they can answer that and other issues.

I'm going to try to find the time to take a serious look at designing a replacement IFS using Mustang II components that will bolt directly to the Butler chassis. If and when I get it done and it works, I'll post it here.

Regards,

Arthur

[decooney]

Arthur,
Did Unique send you any pics of what they offer?

I'm pretty familiar with their front ends as I had mine in out/of my last Cobra a few times which was a Unique, replacing the springs/shocks to a better setup than the Carrera's they offered back then, and playing with the mounts a bit to try and make them stronger... It was like a tubular Mustang II type setup, with their own bushing/mount system on the uppers and and something similar on the bottom. I'll have to call them and see what they are offering. Haven't spoke with the Weavers in a while... On my last Unique it was a giant bolt-in setup with a complete lower cross member tube mounted butted up to the front frame rails, whereas i think my friends is a lower half subframe that splits apart on his Arntz. I'll call them and see what they have. Thanks for the tip...

[lal Naja]

Duane, I just posted a photo to my gallery of the Unique IFS. Take a look and let me know if it's what you have, Arthur

[lal Naja]

Tom, how did you insert the photos in the body of your message? Arthur