Larry Porter Posted July 1, 2015 Posted July 1, 2015 (edited) I have just finished building a rear conversion plate for my R160 diff out of steel. To insure that the ears won't come off, I used 7018 (70k pound) rod for strength, instead of MIG welding. The hardest part was stepping up to the 1-3/8" drill bit for the bushing hole in the ears. I have about 5mm between the ridge of the relief area and the chassis when mounted. Fits up nice. The only problem is heat distortion from welding. When welding on one side of a plate, the steel molecules actually shrink as they cool. This causes the plate to bow in slightly on the weld side, hence the back of the plate will still need to be skimmed. Comments? Edited July 1, 2015 by Larry Porter
Nick Jones Posted July 1, 2015 Posted July 1, 2015 Like it! You done what I've thought about doing for a while. I was going to put a couple of short bolts through into the "ears" as well as welding 'cause I'm not so confident that my welder is powerful enough. How much of a bow do you have? if it is flat enough to seal with a gasket and a bit of sealant, it's flat enough IMO. Bolting it to some heavy plate or even a scarp diff casing while welding might have held it flatter? Keep up the good work Nick
Larry Porter Posted July 1, 2015 Author Posted July 1, 2015 (edited) Laying it on a flattish steel table, I am reading about 10 thou gap on each end of the plate to the table. The sides are slightly less due the weld placements across the narrower section of the plate. Basically, it is slightly concave in the middle at top, and slightly convex in the center on the bottom. This should only cause less clearance in the middle, although, laying the plate on the diff, there is still ample clearance to the internals. I will try to mount when the gasket comes in. It may still need to be faced by about 10 thou to prevent any leaks. Nick, Even bolting it down, the metal still shrinks on the weldment side and will spring up when released. Although, it could minimize it. Will try it on the next one. I used 1/4" plate. Thicker plate (say 3/8") will have less shrinkage over the same length due to heatsinking, but just increases weight. Still may need skimming. Edited July 1, 2015 by Larry Porter
Spit131 Posted July 1, 2015 Posted July 1, 2015 Good to see Larry , You get lots of extra points for doing something different you know . To make you feel better , I had to have my NZ plate skimmed , no big deal . M
Larry Porter Posted July 3, 2015 Author Posted July 3, 2015 (edited) So after building the rear plate out of steel, I decided to tackle the front mount for the R160 diff gong into the convertible GT6. I like Rocky's original layout, but decided it needed to be reinforced to reduce flex. I started with the original Rocky layout. Then I made a front reinforcement plate and welded it on, bending it around the ends. Then, using 2" pipe cut to 1/2" length, I made the bushing cups and welded them on. Should be as strong as the original. I'll mount it in the morning when the paint dries and I get some 3-1/2" grade 8 bolts from the hardware store. Edited July 3, 2015 by Larry Porter
dggt6 Posted July 3, 2015 Posted July 3, 2015 Great work Larry! How have you been cutting the shapes out? Angle grinder, laser? Have you tackled the spring mount yet? Cheers, Doug
Larry Porter Posted July 3, 2015 Author Posted July 3, 2015 Starting on the spring mount today. I am using a grinder and oxy-acetylene torch.
Larry Porter Posted July 3, 2015 Author Posted July 3, 2015 Starting on the spring mount today. I am using a grinder and oxy-acetylene torch.
Spit131 Posted July 4, 2015 Posted July 4, 2015 No stopping you . Lovely work . Could you not have just used a thicker plate though and considering it is bushed is slight flex a problem ? M
2.5piman Posted July 4, 2015 Posted July 4, 2015 Hello Larry, "oxy-acetylene torch." One of my favourite tools, so versatile I can't think of one other single tool that beats it. Alec
Larry Porter Posted July 4, 2015 Author Posted July 4, 2015 Does the plate flexing make that much of a difference? Probably not. I just wanted it to be more integral to the diff and let the bushings do the work more like the original.
Larry Porter Posted July 6, 2015 Author Posted July 6, 2015 Finally got all of the R160 parts finished and test fitted. Fits good and everything lines up well... surprisingly the first try!
Nick Jones Posted July 6, 2015 Posted July 6, 2015 Looks very good. Just one thing...... have you tried the spring on it yet? You plate is quite wide and may not accommodate the natural arc of the spring? Probably not a show stopper as even a moderate lowering block (which you may well want anyway) should solve the issue. Cheers Nick
Larry Porter Posted July 6, 2015 Author Posted July 6, 2015 Nick. It will need a spacer for that reason. Already thought of that and left the sides of the spring plate 1/4" short to accommodate one. Will probably use 1/2" to start. We'll see once it's on the ground. The car is going to be the same Dodge Viper blue. Maybe some silver stripes.
Larry Porter Posted July 9, 2015 Author Posted July 9, 2015 Got the spring mounted on the diff. Made a 3/4" spacer block to account for the 1/4" shorter spring perch and add 1/2" for a little lowering / camber change. May have to change that once on the ground with weight. Still need to get the axle spacers made for the CV axles.
dggt6 Posted July 10, 2015 Posted July 10, 2015 Hi Larry, you mentioned you have put a 3/4" spacer under the spring. When I was comparing measurements of the R160 Suby diff and the Triumph diff, I seem to recall I found about a 1/2" difference between the height to the spring base and the axle centre. My Suby measurements were estimates based on clearance required between the nuts or bolt heads under the plate used for the spring mount. I gestimated that by placing the Suby dif axles centre at the same height as the Triumph axles centre (so the axles didn't touch the chassis) would raise the height of the spring mount by about 1/2". If my calculations are somewhat correct, your spring mounting surface with the 3/4" block could now be 1 1/4" higher than the original Triumph height. Regards, Doug
Larry Porter Posted July 10, 2015 Author Posted July 10, 2015 Well hell Doug! After reading this, I went out to the shop and measured again... you're right! I measure about 1-1/8". I checked my drawings, and for some reason I am off on measuring the original unit from axle center to top of spring plate. I'll take the spacer out and just put in a narrow shim, say 1/8" to allow for spring movement. Cheers for that, saved me some work later. Going to have to get a ruler not made in China!
Bobbyspit1 Posted July 11, 2015 Posted July 11, 2015 Great work, the extra strength on the plate looks a great idea, do you have any drawings or plans for the work? What driveshafts are you going to use? Standard or upgraded units, CV? keep the photos coming they are great Rob
Larry Porter Posted July 12, 2015 Author Posted July 12, 2015 Rob, I am using the Canley CV axles, as we don't have the MGF here in the states. I made templates for all of the parts. Larry
Bobbyspit1 Posted July 14, 2015 Posted July 14, 2015 Thanks for the reply. I may have the top plate and lower plate sorted? I am just waiting for the nod. I think I will add a side plate to the lower plate to add to the strength. I am looking at having the driveshafts made for this conversion. The more pairs made the cheaper they will become. I will take a look at suppliers and get a few quotes. Anyone interested? Rob
Larry Porter Posted July 16, 2015 Author Posted July 16, 2015 I need to get the axle spacers made so I can get the Canley axles installed. Trying to find someone to machine them at a decent price.
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