701 replies to this topic

[bigchief3679]

loving the work guys! I am sure the better box is a worthy upgrade and worth putting the extra graft in!

is the smaller gearbox weak then? i'm sure bigchief is running the small box with a turbo?

i would say that the limit of the gearbox is definitely the clutch. it is so cute and tiny! but i wouldn't go past 100hp with that configuration. this is why i applaud the efforts to use the bigger box as it also has better ratios. i have only had trouble with one gearbox so far and it was due to a terrible mis-shift going into boost going uphill . the other high powered conversions (blue cg13, toyota 4e) have gone on so far without any problems on the small box

[SukiDawg]

an up date.
all been stripped out and painted and cleand up ready for re fit






more pictures soon. thats all folks!

I know the majority on here will disagree, because they read it on the internet once so they must be right - but do you realise how important the main beam across the front of the bulkhead (that the masgter cylinders mount to) is to the structural integrity of the mini shell? Its is checked on the MOT for a reason - not only does it react the front sub frame loads into the bodyshell, but also in the event of an accident its the main thing that restrains the engine from entering the passenger compartment.

Cutting all the way through it to clear an engine isn't just a bad idea for the shell strength, its pretty foolish from the point of view of your safety.

That shouldn't pass an MOT. Its dangerous. No wonder we are getting hit with more and more stringent IVA regs........

[Artstu]

I know the majority on here will disagree, because they read it on the internet once so they must be right - but do you realise how important the main beam across the front of the bulkhead (that the masgter cylinders mount to) is to the structural integrity of the mini shell? Its is checked on the MOT for a reason - not only does it react the front sub frame loads into the bodyshell, but also in the event of an accident its the main thing that restrains the engine from entering the passenger compartment.

Cutting all the way through it to clear an engine isn't just a bad idea for the shell strength, its pretty foolish from the point of view of your safety.

That shouldn't pass an MOT. Its dangerous. No wonder we are getting hit with more and more stringent IVA regs........

Ok I'll be the first to disagree with your misgiuded view

[drummerian]

I know the majority on here will disagree, because they read it on the internet once so they must be right - but do you realise how important the main beam across the front of the bulkhead (that the masgter cylinders mount to) is to the structural integrity of the mini shell? Its is checked on the MOT for a reason - not only does it react the front sub frame loads into the bodyshell, but also in the event of an accident its the main thing that restrains the engine from entering the passenger compartment.

Cutting all the way through it to clear an engine isn't just a bad idea for the shell strength, its pretty foolish from the point of view of your safety.

That shouldn't pass an MOT. Its dangerous. No wonder we are getting hit with more and more stringent IVA regs........

Ok I'll be the first to disagree with your misgiuded view

im finding this interesting plastic, any reason for the disagreement? thanks!

[SukiDawg]

Thats fine, you are entitled to disagree. I'm not overly fussed that you think I misguided, again you are entitled to think this - we're on the internet. SukiDawg is not my actual name after all... Its not whats written on my Automotive engineering degree certificate for example, or my ID cards from years spent in drawing offices, test labs or proving grounds!

Look - not trying to start a flame war or anything like that, but that beam is 2mm thick for a reason. You see this sort of thing so often though its difficult not to mention once in a while just how dodgy things you see on the internet are! If its totally acceptable to cut in half then why was it there in the first place? All due credit to you guys for what you manage to acheive but removing main structural members from a bodyshell is dodgy ground.

Apologies for the fact that I've something to say other than "oooh thats ACE!" - in most cases there is little to be gained from raising such a concern - but you should google the name "Nigel Gresham" if you reckon there are no potential consequences to an iffy modification. IVA gets stricter and stricter as time passes, and it driven by the desire to avoid folks making things which shouldn't be on the road.

The rules are constantly changing, and it will not be long before we have a system approaching that of Switzerland or Norway, where you have to go through type approval.



Many MOT inspectors would pass that because they wouldn't know any better. However, an accident investigation officer would spot it everytime. All the strength's gone from the bulkhead now. I'm not expecting anyone here to take any notice, so I'll butt out. Point made, or vocalised at least.....

[drummerian]

am glad this point has been made, will make careful considerations when i get around to making cut outs!

[johnjamessims]

Early in this post he said he did a micra brake conversion?
i didnt see a answer, anyone know?

[drummerian]

i believe bigcheif has said he did a micra brake conversion but i havn't seen any pictures on how he did this latest magic I am personally going with metro 4 pots for ease but will be nabbing the micra servo off and seeing if there is a possibility of using this!

[Artstu]

im finding this interesting plastic, any reason for the disagreement? thanks!

I'm not saying it isn't perfect or as strong as original, but if done properly I don't think it will make much difference with reguard to some of the points raised, after all there is a dirty great piece of box-section subframe holding the two sides together and I hardly think the engine is going to get past that box-section. Of course not cutting the bulkhead would be be preferrable.

Edited by Plastic rules, 04 March 2010 - 09:39 AM.

[evansisgreat]

Surely we're all dancing round the fact that if you crash your mini at anything over 30 you're gonna die. I'm sure the car is not going to fall apart, and 2mm or even 200mm of (solid) metal arent going to absorb much impact in any case.

[SukiDawg]

I can't help it.... I said I wasn't going to post on again, but if we're gonna have a sensible discussion rather than just being condemmed for disagreeing with the common belief (as is usual) then its interesting and useful to talk about it.

Not all bulkhead mods fall under this - so long as the beam is left alone you should be OK. The panels above and below do contribute to the torsional stiffness of the shell, but very little to strength in bending of it. By that I mean the resistance to force acting horizontally from the front of the car. That was the single point I really wanted to make.

In my project I am actually going to remove that beam alogether beleive it or not, but it is being replaced with something of equal or greater strength, and the attachment points to the internal roll structure are orders of magnitude stiffer than the original would have been. I have to do this to get my engine mount in at the back of the head (North / South installation). If the strength is being put back then of course you can do whatever you like. I have spent a lot of time thinking about this for this very reason.

The point about the subframe adding the strength back isn't really valid I don't think. Looking at it, there are two peices of box section joined in the middle with a peice of plate orientated vertically. Again - in horizontal bending this doesn't have much strength, and would fold in the middle under quite a low load. Also the strength of the weld, and flexure of the suspension tower to which this beam is welded all contribute to the overall bendyness of the design.

We're using coilover suspension here yes? All suspension loads get fed into the ends of the beam we're talking about, where only the shock absorbers would have mounted in the original arrangement. When you hit a bump, a great big force acts vertically on the end of the cut beam, and the only thing holding it in place is the thin material that makes up the rest of the bulkhead - this is going to flex! With the beam intact you have a box section running across the full width of the vehicle, and if you imagine jacking up the car on one wheel (i.e. going over a bump) you're effectively trying to support the weight of the car and occupants on that beam. Just like a wheelbarrow supports the load between the handles and its single wheel. Cut the beam and its going to flex and twist plenty.


Nobody wants to crash their mini - they are not the best car for this to happen in at the bst of times - but to say that something like this won't make much difference is a bit silly I think.....

[Ethel]

The dreaded IVA may be the biggest practical issue in chopping in to the bulkhead.

I'm not sure coilovers need make a huge difference. If the subframe tower is in place you're transmitting the same load as a moment around the upper arm into the same area of the structure: a combination of subframe tower and the end of the bulkhead cross member it's bolted to. Dissipating the force out around the perimeter of the monocoque is the objective, if you're twisting the shell it's much more flimsy behind the bulkhead in a section that cuts through the door apertures. You can see by lots of structures (airframes being a good visual example) that it's the perimeter hoop that matters.

[richardsoniscool]

sorry if its been mentioned but iv read through this a few times a while ago and cant remember.

couldnt you run bike carbs or throttle bodies to clear the bulkhead?

i have liked this conversion from the start the only thing stopping me is my lack of welding skills and the above discussion about body mods.

[harespeed]

sorry if its been mentioned but iv read through this a few times a while ago and cant remember.

couldnt you run bike carbs or throttle bodies to clear the bulkhead?

i have liked this conversion from the start the only thing stopping me is my lack of welding skills and the above discussion about body mods.

Yes Mike your right. Have a look at this thread. Page 6 for the carbs but the whole thing is very interesting (talented guy).
http://retrorides.pr...?...0267&page=1. I know this is not the right way to post threads but I am getting on a bit now. will try to learn how to do it properly soon.

Edited by harespeed, 05 March 2010 - 01:15 PM.

[bigchief3679]

an up date.
all been stripped out and painted and cleand up ready for re fit






more pictures soon. thats all folks!

I know the majority on here will disagree, because they read it on the internet once so they must be right - but do you realise how important the main beam across the front of the bulkhead (that the masgter cylinders mount to) is to the structural integrity of the mini shell? Its is checked on the MOT for a reason - not only does it react the front sub frame loads into the bodyshell, but also in the event of an accident its the main thing that restrains the engine from entering the passenger compartment.

Cutting all the way through it to clear an engine isn't just a bad idea for the shell strength, its pretty foolish from the point of view of your safety.

That shouldn't pass an MOT. Its dangerous. No wonder we are getting hit with more and more stringent IVA regs........

sukidawg, with all due respect, why have you chosen of all places to vent in my thread. have you not been to other websites such as:


http://www.ausmini.c...orums/index.php
http://www.16vminicl...orums/index.php


Do you realise that in 90% of conversions done in minis a rear bar is added between towers to compensate for the removal of part of the crossmember? in original form the minii's towers are connected bya dimpled rear panel that contains many holes and curves which usually become cracked and compromised.
These also reside quite low. The section that is removed from the firewall is made of sheet metal box section which gets narrow at the centre, its weakest point and crumples upon side impact.
It is my belief that the addition of the thick bar at the rear, between towers is a vast improvement over the original design.
i am hoping that this thread does not head in this direction:

http://www.theminifo...x...125736&st=0