Hi all,

I'm just off the phone to Raceline Eng. where we were talking about diff ratio's to suit ZX9R (and 'Busas' I assume) engines. While the Sierra diff guys amongst you have the luxury of ratios such as 3.62, 3.36 or even as tall as 3.14 to choose from, those of us running Timken (English) axles are not so lucky. A 3.54:1 is the tallest I've been able to source to date giving very short gearing in a car with 13 or 14" wheels fitted, although some people claim that there is a 3.1 something out there. If you can find one let me know. After some discussion and experimenting on Excel spreadsheets, a ratio of around 3.1:1 would be seem to the most suitable, considering the ZX9R(C2)'s primary reduction gearing of 1.714:1. (Can someone tell me what it is on a 'Busa?)

This would give you a top speed of just under 130mph on small 6.0/21.0-13 ACB10's (185/60-13 metric equv.) for track days.

Or if you wanted to go to 185/60-14 or 185/70-13 rubber for road use, then it would give more relaxed gearing for long distance work. How does 6500rpm in 6'gear at 80mph sound? This would surely make those longer runs a bit more bareable, save on fuel and the cost of new tyres (185/70-13 Yoko A021's are £40inc from George Polley) as you wouldn't need to splash out on huge 15/16" rubber to get a decent top end speed. And then you have the option of putting the low profile 13" wheels on to give better acceleration and handling for track days. Interested?

Redlines are going to approach the company which manufactures their custom 7" CWP's for use in Sierra Diffs and ask if they'll do a batch of CWP sets of the discussed ratio for English diffs. That ratio isn't set yet so I'm open to arguments for the optimum for our application but it will be around 3.1-3.2:1. Minimum order is 20 I'm told and the cost will be around the £350 mark. A bargain I think. But I need around 10 customers to go to them with to get the ball rolling. Please reply to this posting if your interested and/or contact me at adrianelkin@hotmail.com.

All the best
Adrian

Would have been interested but apparently can't use them on Cortina diffs ....

Why not change back to a Timken (English) axle. It's gotta be lighter than the Cortina item which is a reduction in unsprung weight?

Cos, I've got all my rear suspenion brackets sorted, bought new shoes/fixing kit, handbrake cables, cleaned and painted the entire thing, and don't want to start the process all over again!!! Especially as I really want the car on the raod by next summer and don't want to slow the build down. And I've bought wide wings as well....

Maybe it's an upgrade to do in a couple of years time when I'm gagging to spend lots of money again..

Good news! Just been onto the guys I've been negotiating with to manufacture the custom made diff CWP's. It appears they may be interested in doing a range of ratios and not just the one. I'll keep you all posted.

Regards
Adrian

Ok, back again with more news.

Kinda got fed up with waiting for Raceline to get back to me so I decided to phone Kam Differentials myself. (Their website can be found at http://www.netcomuk.co.uk/~kamdiffs/main.html). Good job I did!

Spoke to Kevin Mason who is the MD of the company. He confirmed that not only has he had several enquiries for a Ford English (Timken) CWP's set to suit BEC applications, but from companies looking for replacment standard ratios. (They just be getting thin on the ground in rallying circles too then) Henceforth, they are currently gearing up to produce a range of English CWP ratio's in a big way.

Once I explained to him about this site and the demand for a taller ratio for BEC use, he sounded very enthusiastic. After asking about timescales ("how soon will you 'ave 'em?") the answer boiled down to the fact that the more enquiries he lets then the higher up the priorty list we'll become.

He therefore invites anyone interested in a 3.1 to 3.2 ratio English CWP to email Kevin Mason personally, stating that you're from the "Yahoo Bike engined Cars Forum" and that you are keen on purchasing a Crownwheel & Pinion set when it is produced. Cost, he quoted me, would be around £320 retail. A bargin in my book.

So there you go. The sooner we make him aware of the interest, the sooner they'll start producing the goods. Send that email to Kevin Mason NOW! These diffs won't get built unless we pester them enough. I've taken things this far so please back me up if your seriously interested.

All the best
Adrian

is it possible to interchange crown wheels and pinnions to get desired ratios on english axles?

Have looked at that, but it's a non-starter for lots of reasons.

We're looking at sometime early summer for them to be available.

Adrian

Have emailed Kevin Mason 4 times now with no reply are they making them? Will they still be available early summer?

Will contact Kam again on Monday to see what the latest news is and report back.

Regards
Adrian

At long last I've received a reply from Kevin at Kam:

quote:

---

Dear Adrian

Still assessing the market and have about 15 people on our database who are
desperate for good quality English gears. Please pass my details onto clubs or
forums and get them to give me their details.

Please find further information on our website, which is
www.netcomuk.co.uk/~kamdiffs. In the next two
months, we will be changing to our new website address, which will be
kamdiffs.com. This new website will be
considerably updated and will have online ordering facilities for greater ease
for the supply of parts.

For further enquiries our fax number is 01483 416009 or email kamdiffs@netcomuk.co.uk.

Best regards

Kevin A Mason
Managing Director
KAM Differentials Ltd
http://www.netcomuk.co.uk/~kamdiffs

---

Does anyone know if this got off the ground? I've emailed Kam and waiting for a reply.