Soild floor mount reforcing(sp?)
Discussion
I fitted solid mounts on my trackday car with no additional plates on the floorpan and had no problems.
For a roadgoing car I wouldn't say it's worth the expense of fitting solid mounts. The normal type are fine if in good condition, but fitting a solid bush under subframe tower bolt is a worthwhile modification.
Neil
edit to make it make sense
>> Edited by Neil8p on Sunday 25th April 21:40
For a roadgoing car I wouldn't say it's worth the expense of fitting solid mounts. The normal type are fine if in good condition, but fitting a solid bush under subframe tower bolt is a worthwhile modification.
Neil
edit to make it make sense
>> Edited by Neil8p on Sunday 25th April 21:40
You are fine to just replace the rubber mounts with solid ones, so long as you do all 6 places. If you only changed the floor ones I would suggest that some additional plating would be necessary as most of the loads would then come out through those 2 points and the floor could develop fatigue cracks. With all 6 done you are really just going back to what the Mk1 & Mk 2 cars had. Use the aluminium spacers at the top mounts rather than the nylon ones.
When you go solid all-round the difference on a twisty road is incredible. the car actually goes where you point it. The trade-off is a bit more harshness and vibration, but well worth it IMHO.
When you go solid all-round the difference on a twisty road is incredible. the car actually goes where you point it. The trade-off is a bit more harshness and vibration, but well worth it IMHO.
Hi Jay
While I would recommend solid mounting the subframe towers and the front "tear-drops" I would leave the lower mounts standard. Two reasons really; firstly it increases vibration and noise transmitted to the cabin considerably, much more than the towers and tear-drops do, and secondly you have removed the last mechanical "fuse" from the subframe mounting system.
What I mean by this is you have already been told that you have to reinforce the floor in the area of the mounting when going solid mounted. If you don't you run the risk of pulling the bolts/mounting through the floor, which is bad. Failing that you could break all the welds between the bulkhead and the front floor sections, which is worse, and is more likely to happen if you have reinforced the floor. All for the sake of upgrading the cheap rubber mounts, which will break if subjected to excessive movement or stress, and hence the term "mechanical fuse".
Unless you are routinely breaking the lower mounts(which would indicate another problem to me anyway), I'd stick with the standard ones. When performing an upgrade on a supposed "weak" part you should always consider the consequence of "strengthing" that part.
Edited to say : Bugger, beaten to it by Cooperman !! I'll second his sentiments that if you are doing the floor mounts, then do ALL 6. I was thinking you were only doing the floor mounts.
>> Edited by phil hill on Monday 26th April 09:50
While I would recommend solid mounting the subframe towers and the front "tear-drops" I would leave the lower mounts standard. Two reasons really; firstly it increases vibration and noise transmitted to the cabin considerably, much more than the towers and tear-drops do, and secondly you have removed the last mechanical "fuse" from the subframe mounting system.
What I mean by this is you have already been told that you have to reinforce the floor in the area of the mounting when going solid mounted. If you don't you run the risk of pulling the bolts/mounting through the floor, which is bad. Failing that you could break all the welds between the bulkhead and the front floor sections, which is worse, and is more likely to happen if you have reinforced the floor. All for the sake of upgrading the cheap rubber mounts, which will break if subjected to excessive movement or stress, and hence the term "mechanical fuse".
Unless you are routinely breaking the lower mounts(which would indicate another problem to me anyway), I'd stick with the standard ones. When performing an upgrade on a supposed "weak" part you should always consider the consequence of "strengthing" that part.
Edited to say : Bugger, beaten to it by Cooperman !! I'll second his sentiments that if you are doing the floor mounts, then do ALL 6. I was thinking you were only doing the floor mounts.
>> Edited by phil hill on Monday 26th April 09:50
I was quick off the mark today Phil!!
Seriously, I would just change the lot. All you are doing is going back to the Mk 1 type of attachment and the loads are then shared between 6 solid joints which must spread the stress transfer into the monocoque better. You shouldn't then need to strengthen the floor either. I'm going all solid on my Enduro rally car and I don't intend to beef-up the floor.
Seriously, I would just change the lot. All you are doing is going back to the Mk 1 type of attachment and the loads are then shared between 6 solid joints which must spread the stress transfer into the monocoque better. You shouldn't then need to strengthen the floor either. I'm going all solid on my Enduro rally car and I don't intend to beef-up the floor.
Wasn’t just Mk1, I think it was mk4 when they went over to rubber mounts, the solid mounted subframes do locate further back which I would imagine spreads the load more. I’ve gone solid all round on my Mini after finding it vague compared to my earlier cars, it mad a lot of difference and noticeably sharpens the steering up.
Paul
I think you're right, "rubber mounted" front subs came in with the Mk 4 circa 1976. The easy way to tell is if you have a large single tower bolt, then it's rubber mounted, if you have two smaller tower bolts, then solid mounted.
I have seen some of the large tower bolts with holes bored through them to allow adjustment of the original Hi-Lo, the one with the interal "hex" adjuster. Of course the later Hi-Lo can be adjusted externally.
Phil.
I think you're right, "rubber mounted" front subs came in with the Mk 4 circa 1976. The easy way to tell is if you have a large single tower bolt, then it's rubber mounted, if you have two smaller tower bolts, then solid mounted.
I have seen some of the large tower bolts with holes bored through them to allow adjustment of the original Hi-Lo, the one with the interal "hex" adjuster. Of course the later Hi-Lo can be adjusted externally.
Phil.
You're right, Paul. All the early marks had solid mounts. When they put those nasty rubber ones in it really spoiled the handling and imparted a sort-of vague feel to the whole car. Maybe I'll look at welding some reinforcing to the floor when I re-fit my rally car front sub-frame. I haven't got to the point of removing it yet, that's a job for very soon when the engine and box are being re-built. I wonder if it's worth using 3/8" bolts instead of 5/16" with bloody great washers under the heads. I'll have a look at this.
Current problem, which I think I've just resolved, is how to fit the FIA approved seats, with the side-mounted frames, when the transverse cross-member is in the way. In a rally car you need the seats with the backs fairly vertical and the squab well forward. I'm going to cut away the flat frame section to sit over the cross-member, then re-weld the flange back onto the frame but higher up over the first 3" of frame. I'll make up two 3mm steel plates about 4" x 3" with a 3/8" nut welded to the underside and weld these plates onto the tops of the cross-member after cutting a 3/4" hole for the nut to sit into. I can seam weld the edges and plug weld through the plates. Then each seat mounting can have 3 off 3/8" bolts each side. That should do it.
Current problem, which I think I've just resolved, is how to fit the FIA approved seats, with the side-mounted frames, when the transverse cross-member is in the way. In a rally car you need the seats with the backs fairly vertical and the squab well forward. I'm going to cut away the flat frame section to sit over the cross-member, then re-weld the flange back onto the frame but higher up over the first 3" of frame. I'll make up two 3mm steel plates about 4" x 3" with a 3/8" nut welded to the underside and weld these plates onto the tops of the cross-member after cutting a 3/4" hole for the nut to sit into. I can seam weld the edges and plug weld through the plates. Then each seat mounting can have 3 off 3/8" bolts each side. That should do it.
Miniman
I got my solid towers and tear-drops from MiniSpares, in fact I seem to get most of my stuff from them.
Some people (not here I hasten to add) have been bad-mouthing MiniSpares recently, but I have found them to be about the best supplier I've used.
MiniShop of London advertise solid mount kits too, as tested by MiniWorld in about 1996............ I'm sure just about any of the speciallist suppliers will do a variation on the theme. Pick your prefered supplier and give them a call.
Phil.
I got my solid towers and tear-drops from MiniSpares, in fact I seem to get most of my stuff from them.
Some people (not here I hasten to add) have been bad-mouthing MiniSpares recently, but I have found them to be about the best supplier I've used.
MiniShop of London advertise solid mount kits too, as tested by MiniWorld in about 1996............ I'm sure just about any of the speciallist suppliers will do a variation on the theme. Pick your prefered supplier and give them a call.
Phil.
Thanks for the info. I usually do my shopping online as it's easier to do it at work without attracting attention! All the sites I've tried seem to list the individual bits, but not a kit. I'll call a couple in the morning. Seems to be a good time to do it whilst the engine is out. If I can get a weekend lined up when I don't have to go to a damned wedding, I'll start the engine build. Spent most of Saturday trying to clean the damn thing up. God only knows how much water I've managed to get inside it... only time will tell! Maybe I'll strip it down totally. Got to get back on the road while the weather is nice, though!
Both Keith Dodd who owns Mini Spares and Chris Wooden who owns The Mini Shop are great blokes. I have the pleasure of knowing them both personally.
Mini Spares is better (for me)for special competition parts and Keith has re-manufactured several original 60's comp bits, even though he'll never make a profit on them, just to keep historic Minis in active competition. Parts like the '11th bolt' for Cooper 'S' heads, 'S' drive line parts and Hardy-Spicer coupling bits, etc.
Mini Shop is great for the more usual parts and keep an excellent stock at Enfield.
If there are any problems with parts supplied it may be because the manufacturers, not the vendors, are using inferior materials. I know Mini Spares had a problem with pistons some time back and now do their own range to their own material spec for the bigger engines.
Why anyone should bad-mouth either is quite beyond me. I find both places excellent and all their staff to be dedicated Mini enthusiasts who will provide advice as well as parts. Whenever I go to either I usually find some sort of conversation going on as to how best to fit certain parts, or how to modify your car.
I heard someone complaining about another Mini parts supplier some time ago. Apparently he had bought a modified head for a 1293 cc car and the comp. ratio worked out too low. Now, as most people know, the combustion chamber size is specific to each car and depends on the distance from the top of the pistons to the block deck as well as the combustion chamber volume. If you just buy a modded head to bolt on you must expect to have to do some machining to get the c.r. correct - you can't just bolt it on and hope that the head modifier had a crystal ball. That's just an example of how some folk criticise when they know not what they do.
Mini Spares is better (for me)for special competition parts and Keith has re-manufactured several original 60's comp bits, even though he'll never make a profit on them, just to keep historic Minis in active competition. Parts like the '11th bolt' for Cooper 'S' heads, 'S' drive line parts and Hardy-Spicer coupling bits, etc.
Mini Shop is great for the more usual parts and keep an excellent stock at Enfield.
If there are any problems with parts supplied it may be because the manufacturers, not the vendors, are using inferior materials. I know Mini Spares had a problem with pistons some time back and now do their own range to their own material spec for the bigger engines.
Why anyone should bad-mouth either is quite beyond me. I find both places excellent and all their staff to be dedicated Mini enthusiasts who will provide advice as well as parts. Whenever I go to either I usually find some sort of conversation going on as to how best to fit certain parts, or how to modify your car.
I heard someone complaining about another Mini parts supplier some time ago. Apparently he had bought a modified head for a 1293 cc car and the comp. ratio worked out too low. Now, as most people know, the combustion chamber size is specific to each car and depends on the distance from the top of the pistons to the block deck as well as the combustion chamber volume. If you just buy a modded head to bolt on you must expect to have to do some machining to get the c.r. correct - you can't just bolt it on and hope that the head modifier had a crystal ball. That's just an example of how some folk criticise when they know not what they do.
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