Wide tracks for an IMP

[nutsster]

Here's a couple of photo's of my friends IMP 1404 that I installed my 33" modified asymetrical tracks on a couple of weeks ago. During the installation we installed new leaf springs and seals in the rear end. The tracks had 6" added to the outside edge of the track and 3" to the inside edge. The mod required 3" widening of the axles, idler and axles. This puts the Imp at about .4 psi on the snow. The flames on the front represent it's performance in deep snow well! It performed great on the first test run.

The pics are not great quality. I'll get better ones this week.

 

[mtntopper]

Here's a couple of photo's of my friends IMP 1404 that I installed my 33" modified asymetrical tracks on a couple of weeks ago.

How does the Imp with an OC4 handle the added stress of asymmetrical tracks? Does it also affect the steering response as I would think it would make it even slower/harder to turn. My experience with the OC4 is you need to plan in advance to execute your turns as the steering response is slow compared to the OC12. I have just been spoiled by the OC12 rear end and automatic transmissions in the LMC snow cat.

 

[nutsster]

I have operated several different Imps and have noticed that some just plain turn easier and better than others. This Imp belongs to my good friend Dale. It is one of the best turning Imps that I have ever operated. My 1402 had the rear end totally rebuilt last year and still doesn't turn as quick or consistantly as Dale's. I'm not saying that it's bad, just more average in handling compared to others.
I know that brake linings, master and slave cylinder set up can make a big difference too. I overhauled Dale's slave cylinders and set up his rigging for steering bands. His brake bands were in good shape ( 80% or better ) so we left them alone and refilled it with 50wt strait mineral oil. It worked very well with the new wide tracks.
I operated my 1402 with these tracks for two winters. At times in soft snow, I believe they turned better than the narrow tracks due to better floatation. In wet heavy snow you could tell that the tracks had more grip and a little heavier steering, but it wasn't surprisingly more. I don't think there is any significant added stress to the C4 differential. It is more important that the suspension is set up correctly. No flattened out leaf springs! Make sure the drive sprockets are slightly off the ground for a smoother ride and a more efficeint turning capability.
Asymetrical tracks on an Imp need to be run with more tension than symetrical tracks. The small front idler wheel and the way the tracks are free spanding across several of the wheels make it a little more challenging to fit with asymetical tracks. These tracks are only 3" asymetrical. The original modification would add 6" to the outside edges only, making them 6" asymetrical. I operated them one winter with the 6" asymetrical and noticed a little more drooping or tilting to the side, but nothing out of limit or undesirealble.
All in all, if you want an inexpensive way to add more floatation to an IMP without spending a lot of cash, this is a good alternative.
Here's some better quality pics of the Imp.

 

[nutsster]

My experience with the C4 in my IMP and OC12 in my DMC would agree totally with MTNTOPPER on their handling qualities. The OC12 when set up properly is real sweet. The C4 is slower to respond and slightly heavier. That's what would scare me from an old Spryte with the C4. However, I do hear that the drop boxes and gearing make up for some of the weakness. I have never operated a Spryte with the C4 to compare. I would love the chance to do it.
Dale's Imp is the closest to OC12 that I have ever seen a C4 operate. I had to look twice to see that it wasn't a Super Imp.

 

[AKdadio]

Hey guys, mine came with wide tracks, but I was wondering if they are set up correctly. Is there supposed to be that much room between the wheels and the belting/track?

 

[Melensdad]

Nutsster, when you guys made the new tracks, what material did you use for the grousers? Is that square tube steel bent to shape? What are the specs on that metal?

 

[mtntopper]

Hey guys, mine came with wide tracks, but I was wondering if they are set up correctly. Is there supposed to be that much room between the wheels and the belting/track?

On my Imp which I do not have anymore, there was considerable room for the sprockets to float in the wheel guides as I recall. I think this was done to allow the track to center correctly between the front idlers and rear sprockets. It almost appears the sprockets should be wider but that was not the case on the factory wide track.
Bill

 

[nutsster]

The original Imp track used a 5/8 square tube with I believe was a 3/32 wall. (maybe an 1/8") It was stamped into the shape to make it perform as a tire guide. A strip of 1/4" strapping was welded over the "drop center" portion for wear and strength. Paddles were added and spaced generously throughout the track. To convert it to a wide track, thiokol recommended installing a 2" solid square strengthener into the tube joint to be welded. I did this to my track, but I think it was a waste of time and unnecessary. A good weld would hold up just fine. "If you were putting that much load on the grouser, it would end up bent in the mid-section."

When I made my tracks, I used 3/4" square tube with 3/32" wall. I welded each section with a 1" X 1/8" paddle to the full lenth. I custom made tire guides that bolt onto the grouser. If I was to do it over, I would just have belded the guides right onto the grouser and saved time and money.
Now my tracks on starting their second season and I haven't had a single problem or bent grouser, even with some pretty agressive use. I have slightly bent a couple paddles by spinning and hitting a rock.

I was cruising around last night following a couple of moose by my cabin when I realized just how much better my IMP performs from what I started with originally. The torsion axles and new tracks along with the more powerful 2.0 liter Ford and automatic transmission has made it a whole different animal. However, like MtnTopper's experience, it's still hard to compare to the 1200 LMC/DMC/Thiokol.

 

[fogtender]

Hey guys, mine came with wide tracks, but I was wondering if they are set up correctly. Is there supposed to be that much room between the wheels and the belting/track?

Mine has the same wide tracks and looks the same, would assume that it is correct or we both have bad track assemblies.....