11 replies to this topic

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Hello chaps,
There is a kit by MiniSpares called Gear Kit Evolution Helical Heavy Duty Kit which if i'm not wrong it's the helical version of the early "S close ratio, straight cut " 

   Well the question is, even if it is mated with a 3.7 diff , 1st gear is long enough to change down to 1st with 25-30mph, But is it possible ? 

 

[Current state... well... it was a std Metro engine with a Fletcher Lcb-Rc40 fitted and Std Metro gearing with 3.7 diff and some Hif mods as per Wizzard states.

She is in, prepping her for 266°Megadyne@103°/10.4:1CR  std engine bore, 36/29mm-940 head, Hiff44-Metro inlet manifold, 123 ignition, LcB-Rc40.

I really don't mind if she tops to 99mph (as she was) as long as she is doing it swiftly. She is a daily driven, road runner. 

  I was... ah okey, happy as she was roaring with 50hp (i guess) and the 3.7diff but with a useless 1st gear, only good for starts on very steep hill. 

With the new set up opted for a greater torque therefore charging tο the "racing" gearlayer and the long first gear to be able to start at a traffic light.
 I think you 've got the picture. ]
 

thanks in advance 
George. 

 

 

 

[Spider]

This Gearset ?

 

http://www.minispare...px|Back to shop

 

Even with a 3.7 Diff, in 1st, it will still be rather tall, it might - just - be managable for street use, though personally, I doubt I'd be able to live with it.

 

Ideally, to get the same overall gearing as the original Cooper S, in 1st (overall ratio is 12.020:1 which I found about as tall as practical from road use) you need to go to a 4.2:1 FD   though I'm sure you'd be able to get away with a 3.9:1 FD, though, at the other end of the spectrum, it's also getting impractical for road use.

 

I'd suggest given your engine spec. such ratios as these are not warranted, I'd suggest the original S Ratios (in Helical) or even the standard sets as fitted from 74 to 83 with a 3.44:1 FD.

[Sprocket]

It'll be fine.

Ratios are almost identical to the Minispares clubman straight cut gear set and there are loads of people using those in all sorts of configurations on track and the street.

The 3.76 final drive will help first gear for sure.

Ive just fitted the c-stn48 gear kit to replace the clubman gear set. Ive got the 3.44 final drive.

[attachment=194121:C09A7726-E869-4C00-A0D2-7D902D38254A.jpeg]

[attachment=194122:D887E1D9-8D1F-4AC5-B462-FCC16DC02965.jpeg]

Edited by Sprocket, 10 March 2018 - 09:02 AM.

[carbon]

George,

 

Getting the right gear ratios will make a big difference in overall driveability, worth taking a look at Guessworks's gear ratio calculator: http://www.guess-wor.../Tech/ratio.htm

 

Some other areas to consider:

- what size wheels are you planning to run

- is your car skinny (<550kg), 'standard' weight (650kg), or full fat (>750kg)

- what valve lift are you aiming for with the MD266 cam?

 

Reason for last question is my 1293 is using 266 cam, and I have found that the A+ sintered rockers give nice tickover. But if you want a more exhilarating driving experience you need 1.3 or 1.5 ratio rockers. And if you use >1.5 rockers then close ratio gears might be useful.

[Sprocket]

I found even with the 87lbft torque of the 1400 on a standard A+ gear set and 3.76 final drive, first gear was useless.

Gr4h4m uses the clubman gear set and 3.76 FD in his 1070 based supercharger build, and gets along with first gear no problem.

Edited by Sprocket, 11 March 2018 - 08:44 AM.

[Allrounder]

[quote name="Sprocket" post="3526251" timestamp="1520757577"]

I found even with the 87lbft torque of the 1400 on a standard A+ gear set and 3.76 final drive, first gear was useless.

Why was it useless??

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  Hello, 

Τhank you for your views, completely different and with enough distance between them to cover.

 

 Hmm where to start of ... i'm kind of guy who likes it as classic as possible for the modern roads and traffic.

Don't like the "many and complicated things". i love the minimalist aspect of it. 

 I accept tuning to the point of taking things further and make it more efficient but saple. 

Therefore no more gauges than the three clock binnacle ( i see the water temp, watch the oil pressure, understand my engine oil status)

No power electrics of any kind, not an aux electric fan, just 1 big row alu rad with 11 blade fan.

No heater unit, i have 10 months above 20°C why bother with this big black noisy thing, it is blocking my view! Out of the car with all of vents and ducts.
No speakers, no head unit. Cruising down to motorway with 80mph it's like having a ride with wwII Avro Lancaster, which i love the buzzness of it and the noise and smells especially in the summer time with the windows down, air storming in down to my toes. So why bother! Out of the car. I put my headset on my phone and voila!
 

Oh sorry chaps, i carried away... it happens with minis... 

-So, yes i think it is more like standard weight but to the skinny side. Somwhere to the 600kg area. 
-10 inch of course . 
-I'll start with the standard rockers and valve springs too. If i'm happy with it, it stays as is. i'm aiming particularly to this tickover. 
(I played with Guess-works speed tables for over a month... but i need your opinions and to share mine)

What i want from my engine is to have a reasnable idle, below 1000rpm, progressive torque curve that tops at 4-4.500rpms and power up to 6500. 
I understand that a standard gearset with a 3.44 diff would be fine (like an average)  but i need to help my engine for my driving habits, let's say that i'm aggressive.
This is why of close ratio. The 1000rpm drop from gear to gear is super sport enough and don't need to push the engine to red line all the time (Well thats a... not so sure but...  well hahaha) 

 I love driving her as fast as kind of cosy racing to B roads (who wouldn't) this is why i need of the long 1st. 

Let's say that i'm entering to a u bent what i need is to be able to change down to 1st gear. 
As per GuessWorks tables 1st would be like a middle gear between 1st and 2nd . So,  instead of having 2nd which would be long with whatever suitable other gearset or a short as 1st gear,  i would have an appropriate 1st gear to drop in and accelerate fast away. But is it possible to change down to 1st with 25-30mph on the clock? Or this is not gonna happen to a mini gearbox. 
(eg. Rs Renaults, you can comfortably kick down to 1st with 30mph)
 

okey from time to time i have to give my mini to my wife too. She can manage whatever you throw at. Very good driving skills but she will go for a couple of ridings downtown, therefore the question about traffic light. 

 

 

George. 

[carbon]

Hi George,

 

You're looking for a 1275 with MD266 to have 'reasonable idle below 1000rpm, progressive torque curve that tops at 4-4.500rpms and power up to 6500.'

 

The MD266 is a great all-round cam and good choice. You can get a good idle below 1000rpm with MD266 using rockers up to 1.65 genuine ratio (10.5mm lift at the valves). With 1.65 rockers i have found this also moves the peak torque further up the RPM curve and good power to 6500 or more... If you have a 'press on' driving style then don't fit the A+ sintered rockers - in my experience they strangle the top end performance regardless what else you do to improve the engine.

 

With the MD266 in 'press on' driving there will not be too many situations when you need to use first gear to get around even quite sharp bends. If you go for the close gearset with 2.5 first ratio and 3.76 final drive (9.4 overall) you will find it is slower away from a standing start in the dry than the GT/S gearset 3.35 first gear with 3.1 final drive (10.4 overall).

[page]

Hi chaps, 

 

So you're suggesting the use of the 1.5 rockers.  Well thanks for that . To be honest i'm looking for the lightest possible valve springs for my application . some 170-180lb

Understood... that the car might be slower from a standing start but this will be the least worry for me . I don't "drag" my car from traffic light to traffic light. Hahaha that's so childish .

 

But the question still remains.

Can i change down to 1st gear during 25-30mph to a mini gearbox. 

Do i need to purchase something more to support this action? ( some bulk rings maybe ? )

 

I can't answer this question my self, cause when i first bought her, six years ago, she was already have the problem with it. (changing down to 1st gear)
During the years this get from bad to worst. Now days i have to be almost stand still to select 1st gear. Obviously this is a problem which needs to be fixed. 

Despite this i would like to go further, therefore the close ratio which i believe will serve my needs. 

 

*As i see it from my view i will have 4 gears to play with (except from standing starts which might be a little problem ) . Or of having three gears!  dispite that the engine will be torquish or like now which i have 1st for hills, 2nd like 1st but long but do the job and left me with 2 gears to play with. 

George. 

[carbon]

I'm using these Minispares AEA-526 valve springs with MD266 and 10.5mm valve lift: https://www.minispar...c/C-AEA526.aspx

 

But if you're looking for maximum torque at lower rpm then 1.3 or 1.4 rockers would be better choice. With these rockers you should be OK using these lighter poundage Minispares AEA-525 valve springs: https://www.minispar...c/C-AEA525.aspx

 

Sounds like you issues with selecting first gear might be worn syncromesh? But if you regularly shift into first at 30mph it will be getting a hard time and syncro probably won't last long even using a new gearset.

[OzOAP]

Re. valve springs
I stock A Series 'conical' springs. Ideal for your application. Have a look.
Strong seat poundage but softer 'over the nose' (full lift).
Smaller, lighter topcap.
Single spring so no frictional losses or heat.

www.facebook.com/ozoap

Edited by OzOAP, 13 March 2018 - 07:27 AM.

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@ Carbon, thanks for all your suggestions. Yes i'm sure that my synchromesh is bad and will be fixed together with a racing spec bulk rings to break the speed and for durability .

 

@Ozoap, i'm so glad that you knock my door. This is exactly what i was looking of !

I'll pm you . 

 

@Sprocket, i will appreciate some feedback or you can upload a video when you drop your wheels on the road . 

 

 

Thanks all
George.