Diff Ratios

Post by **martylemoo** » Fri Jun 04, 2004 8:03 pm

Hi,
About to put a 1340 MED engine tuned to 100bhp with a kent 276 cam mated to a ford type 9 5 speed box and i was wondering what diff anyone would recommend me to run. I am going to fit uprated half shafts etc so it is just the diff i need to sort out.
Thanks
Martyn

Post by **racer** » Fri Jun 04, 2004 8:44 pm

Over to you Cam !!!!!!!!!!!!!!!!! lol

Post by **Matt** » Fri Jun 04, 2004 9:32 pm

Cam is running a ford rear axle.......

Post by **Cam** » Sat Jun 05, 2004 1:43 am

Yey!!! Another MED fan!

I am running an MED 1380 with a Ford type 9 and an Escort MK2 rear axle and a 4.44:1 diff.

Sierra rear wheels, but Peugeot steels to go on.

For more info see:

http://potteries.mmoc.org.uk/Members_Ca ... 9_1000.htm

Any questions, please feel free as I wish I had some advice when I was building mine up a couple of years ago................ I have made some silly (and costly) mistakes!

To be honest, running 100 BHP through a Minor axle is not such a good idea, even with hardened halfshafts. It will be VERY strained.

But if you really want to, then go for the standard 4.22:1 1098 type diff if you want quick acceleration (which I assume that you do). If you want a motorway cruiser then use the Midget 3.89:1 diff.

I tried the Ford 3.89 and it was WAY too tall.

Post by **racer** » Sat Jun 05, 2004 9:06 am

Cam , Just had a look at your site .........Now thats wot I call a real "street sleeper "!........

Post by **Cam** » Sat Jun 05, 2004 9:46 am

Thanks mate! Any chance of a piccy of yours?? or do you have a link to a website or something??

Post by **martylemoo** » Sat Jun 05, 2004 10:31 am

thanks Cam, very useful site. I will probably be in touch with a few questions when i embark on putting my many pieces together.

Post by **rayofleamington** » Sat Jun 05, 2004 9:13 pm

martylemoo,
Are you after accelleration in 5th or quiet cruising?
If you go for the 3.9 or 3.7 you will have a more relaxed motorway cruise in compensation for less all out accelleration.
As mentioned, 100bhp is a little high for the minor axle, although not impossible and spares are very easy to come by.

Post by **Cam** » Sat Jun 05, 2004 9:56 pm

If you go for the 3.9 or 3.7 you will have a more relaxed motorway cruise in compensation for less all out accelleration.

Yes, but with the Ford 5th gear (0.82:1) you effectively get 4.22 x 0.82 = 3.46:1, so it's like a 4 speed Standard Minor with a 3.46 diff which gives some VERY relaxed cruising!

Mine being a 4.44:1 gives 0.82 x 4.44 = 3.64:1, which is almost the same as a standard Minor with the 3.7 diff as mentioned by Ray.

As mentioned, 100bhp is a little high for the minor axle, although not impossible and spares are very easy to come by.

Yes, the spares for the Minor axle are significantly easier to get than spares for the Ford axle and you don't have to worry about making it fit!!

If you are going to run 100BHP then you might want to consider uprated rear telescopic shocks and radius arms (from body to axle) to prevent axle tramp when harshly cornering and accelerating. I have some fitted to mine and it has completely eliminated the terrible tramp I was getting before with the standard axle setup.

Post by **IslipMinor** » Sun Jun 13, 2004 8:50 am

I have a 1380 with the Toyota 5-spd box. The engine has been on the rolling road and has 95 bhp at the wheels, about 112 at the flywheel. I have a 3.9 diff in a standard Minor casing. With 13" wheels and 185/70 tyres this gives 20 mph/1000 in 5th. I wanted a good combination of performance and cruising, and the 3.9 is at the limit of this for the set up I have.

With the Ford 0.82 5th gear, and 14" rims?, I would think that the 4.22 would be plenty high enough.

Strengthwise, after fitting a Tran-X limited slip diff, I immediately broke one on the toughened halfshafts, and had already had problems with the hub oil seals after about 25 enthusiastic laps of the Imola GP circuit as part of the Euroclassic 3 years ago!! As a result I fitted Peter May's double bearing hubs, and EN24 race halfshafts - no more problems on the last two Euroclassics.

I also have anti-tramp bars, Koni telescopics, front and rear anti-roll bars, and poly bushes everywhere - the handling is amazing and shows what could have been done towards the end of the Minor's development. Aoart form the poly bushes, everything else was well known and practised in the 60's.

Post by **rayofleamington** » Sun Jun 13, 2004 12:42 pm

Yes, but with the Ford 5th gear (0.82:1) you effectively get 4.22 x 0.82 = 3.46:1, so it's like a 4 speed Standard Minor with a 3.46 diff which gives some VERY relaxed cruising!

- I overlooked the comment on using a Ford type 9 box, therefore Cams info on final drive ratio is correct, and mine was ok if you are using a 4 speed box