mk1-forum.net

I am at last at the age where I am preparing a road car for my son.
He has told me he wants it to “sound like your race car, dad”
I don’t think a S/C box on the road is a good idea but do you think we can get the sound he’s looking for by just swopping the drop gears? Apart from the noise (which he’ll grow out of when the girls will inevitably start getting lifts from his mate with a 2013 Golf with heated seats) what are the potential pitfalls?

No pitfalls apart from the noise. Depends on the journeys really.

I wouldnt worry too much, when he starts tuning it up (which he will!!!) as hp increases the helical drops can chew in through the side of the gear casing, not a huge issue as you can get them bored out and sleeved but a set of SC drops lessens the risk of that happening. I actually like the noise, deafens out the other half's moaning about my driving! Got a set of SC roller drops to go in my next engine sat on the bench along with a set of SC gears

Modern S/C gear sets are not nearly as noisy as the old ST ones. We have 2 minis, both with S/C gearboxes. I like the close ratios and my wife likes the noise! Go figure.
They are not heard in 4th at all as it is direct drive. Fitting S/C drops on a road car will not be very pleasant. Screaming noise in every gear and no point fitting a radio or ICE into the car. Just ear defenders to stop the headaches.

Son will still pull the Birds in a Mini .. however maybe not if you fit straight cut drop gears .
just stick on a RC40 Exhaust & they will be happy ever after

Following this thread carefully as I will be fitting a SCCR box into my 998 Cooper (with a 1330 engine) and have acquired what I think is a NOS set of ST drop gears ...

I think one trip out in it will put the Mrs off, so I can then have some fun on my own.

Whatever, it will surely sound better than those awful ST's, RS Audis and VXR's popping and banging at every opportunity

Thanks chaps. I'm sure I can lash up something suitable...until he sees sense and buys a Golf

Just built myself an engine. Straight cut box and roller SC drops. Love the noise...and reliability as the car is a bit heavier than a Mini.

If you really want it to scream use a straight up crown wheel and pinion.
They scare woman and make little kids cry.

Straight cut gearset, roller drops and straight cut crown wheel and pinion in my car, the noise really seems to excite dogs!

Three out of three for me then!

Sc gearset and old school timken roller drops in my 1430 Rover turns heads to an embarrassing point......but sounds great

When I'm serious about cutting noise I have my gear set REM treated. It's a polishing process and leaves every gear looking like a mirror. A Vintage race customer after a few laps with his new gear box pulled in wanting to know why I removed his SC gears ? I like to play with trannys and have several DAM 5626 rod changes with 2.76 CWP and two O/D drops. I have had the gear set, drops, CWP, spiders and diff outputs all REM treated. At 3000 RPM and 70 mph wind noise just begins to become the problem. I have two NOS dog box gear sets a JKD multi spline standing start and a Swift rolling start. The Swift is such a delight to use I'm thinking about a 4.65 CWP and running it in my new Mk1 street project. Steve (CTR)

CooperTune wrote: ↑Thu Jan 07, 2021 3:16 pm ,,,,,,, I have my gear set REM treated. It's a polishing process and leaves every gear looking like a mirror.,,,,,

It's an interesting process and one I'd not heard of before, but looked it up;-

https://www.remchem.com/applications/co ... s/gearing/

I can see it's advantage and potential to reduce noise, but I would think to get the benefit from it, the gears themselves, when fitted would need to be quite finely aligned to each other, what's been your experience in this regards ?

I'm not sure how one would go about aligning the gears. I began using the process years ago when the shop that cryogenic treats my disc offered it. There have been claims of a 2 hp per 50 hp reduction in power loss though the gear box. Nick Swift flew over and drove our Vintage car to a VIR Gold Cup win. In our classing system Group One has five classes the classic mini runs in the middle class. Nick lead every lap of every practice, qualifying race and feature race setting a lap record. That was for the entire group. I believe Swift Tune offers the REM treatment with their gear sets. Steve (CTR)

I think both Swiftune and MED offer their dog kits in a super finished option.
Don’t know what the price premium is.

GraemeC wrote: ↑Fri Jan 08, 2021 8:03 pm I think both Swiftune and MED offer their dog kits in a super finished option.
Don’t know what the price premium is.

MED was a couple of hundred quid more for superfinish.
Companies are super finishing a lot of stuff now days. Gears, cranks, followers, cams....
I found one 'cheating' company had superfinished a Mini 7 cam, when regulation stipulates you must run an "unmodified CAM6648 as supplied by the club".
The scrutineer passed it as ok...clown.

[/quote]

MED was a couple of hundred quid more for superfinish.
Companies are super finishing a lot of stuff now days. Gears, cranks, followers, cams....

[/quote]

I've got a 'super finished' MED cam and followers.
I is an exceptionally smooth feeling finish.

I'm running s/c drops on my coooper, yes they are flippin' loud and i would not recommend them for a daily drive to work.
However , my car is for fun weekends and the odd track day and i love the sound.

Anyone got an 'in car' recordings of their straight cut drops they can or want to post a link to ?