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MG Midget and Sprite Technical - To straight cut, or not....
Ok, I'm planning to rebuild my spare box, and contemplating a straight cut gear set from mini spares (for spridgets ofcourse) Question is; do they make as much noise as rumoured? Because Mr. Keith Calver has written an article in wich he states that a quality cut gear set won't make that much noise. In a race mini it's mostly the drop gear, wich we don't have. So to straight cut or not. |
Alex G Matla |
If im not mistaken .. I think straight cut gearboxs are only good for the race track, and will wear out fast on normal roads under normal driving... dont hold me to that. but thats my understanding. id certianly consider a 5 speed box for what it will cost you for a straight cut box Prop |
Prop |
LOL - not that I'm trying to get rid of it or anything - but - I've got a type 9 ... ;)! Why are you changing? |
rachmacb |
Straight cut induces less friction, meaning more power at the rear wheels 8^O I will NEVER put a ford box in my midget. I've got a Mondeo, and I don't like it. |
Alex G Matla |
I guess the noise level could be reduced in the Midget compared to the mini - but, let us know how it works out if you do it :)!!!! |
rachmacb |
Ofcourse. It's a bargain at 400 euro's, if it not ok I'll just bin it... Nah. BTW, you're up bright and early, busy day with horses and courses? |
Alex G Matla |
hmmmmm - bargain ...?! No - the dogs were whinging very early, so let them out, and now it's raining, so I'm hiding from that now! Plus, looking for parts ... :) I think today will be a bit cooler, so I might get away with not having to muck out by 8am! |
rachmacb |
Figuratively speeking ofcourse :) |
Alex G Matla |
LOL - on a serious note, I am probably going to sell the type 9 - but - for not that expensive :)! I have my eye on something else ............. |
rachmacb |
Sjeez, same gear set in the states, almost triple the cost!!! 1200 bucks!!! |
Alex G Matla |
hmmmmmmmm - shall we fill my container and make a mint? Who needs house belongings and clothes at that mark up! |
rachmacb |
Im wondering if the gear box sound wouldnt resemble that of 1st gear in a ribby 4 speed,,, thats a non-syncro gear ....has a whinny sound. So im guessing it will whin in all gears if the gears are straight cut...Trust me, Im just guessing, I have no info to back up what Im saying, so Im probably wrong. You might give mark T. a shout, they have whats known as a "T2/T3" toyota transmission (5 speed) in AUS, with a nice conversion bolt-in kit, you might give that a looksy if you dont like the ford 9 tranny Unfortantly I cant remember the name of the compaany that makes the toyota tranny conversion, but they are in the land down under, OZ, AUS. So mark T should be able to help you out. |
Prop |
Rach, Even better, wear all your clothes. I'm sure they will let you pass at customs, they are very friendly and gullable in the states... Prop, I'm willing to go the datsun way, but that not very easy to find. |
Alex G Matla |
LOL - I would look like the michelin man having eaten a diet of McDonalds - obese! Plus, I hope that, if it does finally all work out ever - to travel with the horses :) Watch out though - coz that's via Schipol ........ |
rachmacb |
So, put the house belongings with the horses. Or, take a huge container, sell at enormous profits and get a nice fully furnitured ranch. Or a little house on the prairie.. |
Alex G Matla |
LOL - I've already thrown the car out to drive it ...! Better go and feed the aforementionned - while I still have stables left to sell - the rain seems to have stopped now :( |
rachmacb |
Alex, they are rare, but come up about once a month on ebay...Good news, with the economy dropping thur the floor, they are once agian resonably priced Ive seen them go this year for as little as $250 to no more the $700 tho thats rare ... on avg about $450, compared to where they where 3 years ago of around $1200 I saw several times,,, thats insane and mind boggling. 2 on evil bay currently Prop |
Prop |
Got the numbers? I don't exactly know what type(s) are ok. And I'm a visual guy, if I can see the pics its better |
Alex G Matla |
heres for the 2 listed on evil bay 330445543420 230492319670 here is a descripition of what your looking for http://rivergate5speed.com/desc_of_trans.html |
Prop |
wow, DID YOU SEE THAT... if you read the bottom of the page in my last post link... there is a recent add-on, apperantly these tranmisions are avialable in the UK |
Prop |
Hey alex theres a datsun sunny that may have the correct tranny you want... its 250GBP, that would be worth it take the tranny and sell the car to the scrappers...and its only got 69,000 miles on the clock...certianly worth a call esp. for a break even/ free transmission Prop 290446536433 |
Prop |
If you look at the interior shot of the Sunny, you can see a 4-speed gear knob. |
Dave O'Neill 2 |
I ran a straight cut box with an FJ engine in the Frog for several years. Initially I loved the noise and at high revs (and especially through tunnels) the thing sounded amazing and it drew a lot of attention. Later with work and longer journeys it became tiresome, and was swapped for a regular box. I think the pleasure/pain threshold for me was when I was 28. Incidentally, thanks for the diff Dave - I'll be putting it in this afternoon. |
F Pollock |
thanks dave...I didnt see that, that sucks Prop |
Prop |
If you've ever been to one of our Midget races you will have heard the noticeable and pronounced whine from the straight cut 'boxes as the cars move around the paddock. At 'manoeuvering' rpm I notice it even with a helmet on. At race rpm it's not so marked owing to the noise of the engine/exhaust. I doubt very much that I could live with it for any length of time on a street car. |
Deborah Evans |
I have a sccr box in my turbo car,BUT no windscreen,so wind noise drowns gear scream.Running with a screen ok,but i guess with a top on it would be too much. |
steve cowling |
why not have the first 3 gears SC and the 4th helical that way you still get the comfort when cruising |
Onno Könemann |
Onno, remember that 4th gear is straight through (no gear reduction), but the whine is still there because all of the other gears remain in mesh, singing away (though, without any load). ":o) Norm |
Norm Kerr |
Straight cut gears are noisy, no doubt about that. Most large lorries use straight cut gears in their transmissions and you have certainly heard those. The first gear in your box now is a straight cut gear and we all know what those sound like, imagine that in all four. Wear should not be an issue, in fact it is probably better on the straight cut gears than on the helical type as there are less sliding motions between teeth involved. The problem that might arise is in the type of synchronizers. Most straight cut racing gears are designed for dog engagement without synchros from what I've seen. That would make for a very rough shifting box on the street. If you can get straight cut gears designed for standard synchros and don't mind the noise it should work fine and be a bit stronger than the helical box. |
Bill Young |
Many - but not all - Spridget first gears are noisy. This is more often than not due to wear/damage to the gears, not because they are straight cut, but because it is a crash gear and they get a lot of abuse. |
Dave O'Neill 2 |
damn Norm had not thought of that! :) But Alex ever driven that MG C with straight cut box in servcice at the WS? a good indication of the noise |
Onno Könemann |
Onno, no, I've never even knew there was a C like that at the MGWS. Maybe because I'm not interested in C's. But I'll ask the managing director... |
Alex G Matla |
Prop The original *ahem* Frontline *ahem* 5-speed kit was a Toyota 5-speed T50 box. This box is quite large and requires custom mounts and some cutting of the transmission tunnel floor + the chassis rail that runs infront of the front seats. The T2/3 box from the 5-speed Starlet requires much less in the way of cutting and as such is preferential in our books as it is smaller and weighs less. We have our own T50 conversion in development, but the boxes themselves are hard to find in a good enough condition to resell, on top of that some of the major parts of the box are no longer available, as such making life very difficult when it comes to reconditioning them. However, we have yet to encounter any problems whatsoever with the T50 and as such will continue our development in very small numbers for our own cars to begin with. Again, everything is alloy to save on the collosal weight involved with the typical steel backplate, mounts and we are still arguing over cost effectiveness and of course longevity of propshafts. Either way we will keep people updated, that way they are welcome to use what information we gather together for the conversion. Pete |
PeterJMoore |
Hey peter The T50 is a bullet proof box, but like you said, Itsa lot of cutting and welding and I fear beyound the avg. shade tree twicker (okay me...LOL) besides I think that would work better for the 1500 or an MGB, But I think better then the T50 tranny would be the 5 speed tranny from the Mazda 280ZX ...there common as rat poo, and super cheap for a low milage box, but its gonna take some cutting and welding...I know rivergate does the 280 zx kit for the MGB, but i got to say the MGB engine (B-series) is just a bit bigger then the A-series engine So Id think it could be adapted without to much fuss... if you can make it fit into the tunnel (But Im just purly guessing on that idea... Im sure there are 299 reasons why it wouldnt work) But from what Ive read the toyota T2/T3 box is the way to go in that part of the planet |
Prop |
Alex, SC gbox is noisy (except in top)but not so bad in Midget if you have the hood down a lot. IMO not practical for non competition use. Pete, I run a T50 (I agree with you an excellent box) I would be interested in purchasing an alloy backplate to replace my steel one, I will keep an eye on your website. FYI mine is fitted without cutting the floor, only the X member is removed, but my battery tray is removable to accomodate fitting. Ian |
Ian Webb '73 GAN5 |
Straight cut gears are MUCH stronger, and yes, they are noisy, but only the first three, and the noise is fantastic!! I ran a straight cut box in a Westfield (Lotus) Eleven, after stripping the gears in two standard boxes, and it all adds to the thrill of a good car.................. in my opinion. |
D le Versha |
OK - Ian and Pete - a serious question since I know that both of those cars are pretty darn good (and I know that Ian runs in 2nd hard!) Doesn't it being a 5-speed gearbox affect this running - and how does it react in 2nd gear - especially with a slip dif? Yes - you know I want exact explanations ...! |
rachmacb |
Rach I'm not sure what you mean by this: "Doesn't it being a 5-speed gearbox affect this running" It runs just like any other gearbox really, the most useful thing on the autosolo is being able to change down to first gear on the move when I got to those 360 degree turns around the single cones. At the solo where we chatted I was seeing just below 6K rpm in second, but I do run the earlier 4.2 diff, but that speed would be the similar with any gearbox. The LSD makes no difference to the gearbox, mine is a Quaife which is quite a "soft" type anyway, I suspect Pete and his autotesting experts in NI run plate diffs which can be set up to have much more aggressive locking, it certainly appears that way when I have watched them, can you confirm that Pete ?? Alex apologies if we muscled in on your thread. Ian |
Ian Webb '73 GAN5 |
A Westfield XI is a different car to a Spridget despite it using them as the donor car to build them I bet the XI isn't used as a regular or daily :) I've been in a Mini with straight cut gears but everything was noisy in that the double fuel pumps were the noisiest things betting even the pespex windows If you can put up with a loud sports exhaust noise everytime you drive then you might put up with the sc gear noise I'd love a ride in an XI Many years ago I parked next to one at a show in my Westfeild SEiGHT (Lotus 7 copy) Photo doesn't really show how low XI are, it would not have got over that marker plate in front of it |
Nigel Atkins |
Nigel calling an SEiGHT a lotus seven copy does not realy describe it a lotus seven copy with big lump of V8 is a better description ;) |
Onno Könemann |
You're right about an Eleven being a different car to a MIdget, but it was used every day, and for very long distance runs. My Sprite is noisier than almost anything I've ever had, but it does have a side exhaust and a stripped out interior. An Eleven is the BEST car in the world for driving fun, so I'm building another one now. |
D le Versha |
LOL Ian - perhaps THAT would explain why my car was acting a bit strange coming out of the spins ... I thought you did it ALL in second!!!! Oh well, seemed to work for Primerose :) Alex muscled in on changing the thread days ago - about 3am - when it was raining and too miserable for me to decide to go and work ... ;) I think his wonderful suggestion was that I could wear all my clothes when flying with the horses, so I could fill my container with car parts ... Thanks for explaining - it's always good to learn from people like you - and one of the great things about being a member of a club who put on lots of things like this - Sheila has said they'll have more if people ask ..........;) |
rachmacb |
D le - you use your XI as everyday and distance runs, wow hardcore, well done And you're building another one, let me know when it needs test driving I know of one part built now that probavbly will never be completed unless it's sold on but don't know if it will ever be sold on either Rachel - I thought you were touring Canada and stopping over the winter to return later so now feel foolish about some of the stuff I put, I should have checked with you Onno - my other SEiGHT had a slightly bigger lump - but I chrashed it so decided to get the slightly smaller yellow with the insurance |
Nigel Atkins |
Nigel bigger lump?! then it should just have been called rocket right?! |
Onno Könemann |
Nah, only soft 4.6 and 3.9 factory built Euros with carpets and heater for weekend touring My mate has a 4.3 former hillclimber (that started life as a 1.6) now that goes like a rocket even before he removed the windscreen And I know of a serious race built 4 litre it's heavy in weight and overpowered but boy does it roll up the tarmac in summer (it's for sale) |
Nigel Atkins |
Naw - don't be - I never tell the whole story anyway - I reckon I'm probably the one who gets most people confused most often - and then whinge when I'm confused :)! Perpetual confusion is a good state to be in!!! As ever, the Canada thing is always one of the things that sits in my mind regarding any changes I make - YES it would be good to have the 5th gear to cruise in, especially over longer distances, but ....., well, I know her as she is, and can't always get my head around "new" and worry I can't do it myself - oh my brain hurts! Truth is - the Midget50 committee all want to have my guts for garters, so, I'm making my escape BEFORE it - that way they won't realise I've gone when they come baying for my blood afterwards :)!!!!!! |
rachmacb |
I have a straight cut box in my B for 25 years, used it as everything from race & rally through to daily commuter and family car. Love the noise, nothing like it. :-) Definitely not overpowering. We have 5 speeds in 3 of our Midgets (one Toyota Starlet, one Datsun Sunny, one Supra). The first two fit without any tunel mods at all. The 5th gear is a definite plus, but spares are a definite problem. On the other hand, they last a lot longer than the original ... we have one other Midget still with an original ribcage box, but it has started to get growly after 5 years of autotests. Lovely to drive though, if only it had 5th! |
Paul Walbran |
Well, seems like a winter job has become a job wich can't wait. This afternoon first gear was jaulting, so decided to skip first on the way home. Carefully tried when home, no good. Put in reverse to back up into garage and clunk drive, clunk drive, clunk full stop gearbox stuck in reverse, no more movement! It will drive in second, but not in first or reverse. Any ideas? I will first rebuild my other box and, depending on state of laygear, decide to go straight cut or not. |
Alex G Matla |
LOL - not sure you can have mine now - even if you did want it :P |
rachmacb |
Whatever you do get your car running first(reasonable 2ndhand box) and then take your time to decide what to do. Btw, a Ford box isnt so bad, admitting driving a mondeo is tho. LOL!! |
Arie de Best |
I was thinking - IF I were to do the conversion which I'm now quite tempted to - do you want my old one? Can't remember which year you are though Alex? |
rachmacb |
(reasonable 2ndhand box) is what I thought I had bought, after I broke a tooth from 1st gear at Assen. So I'm not going to that again, two gearboxes is enough for me. Rach, do you mean me or the Midget? 1967 and 1973... |
Alex G Matla |
LOL - I meant the midget - I don't know if you need to change gear, but, that might cost more in session than one for her ;)! We can talk about my rates though ...! Nice to know that you're older than me though :) Rach - doesn't need any more mad clients! |
rachmacb |
This thread was discussed between 29/06/2010 and 04/07/2010
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