Morris Minor Owners Club

Would anyone be kind enough to plug the following spec engine in to win su for me and tell me the recommended needles?

1275 + 60thou (1330)
Stage 1 12g940
LCB Exhaust with 1.75" Exhaust Twin Box
Alloy inlet manifold
HIF44
Standard Airfilter
Standard Rockers
Standard Ignition
Standard fan

I think thats everything relevant engine related

Thanks!

Something like a BDM will get you going Matt!

WinSU recommends BHD.
Might I also say, what a stonking spec!

Its also claiming an estimated 75bhp at fly and 0-60 of 11 seconds! (assuming a standard 4.2 diff ratio and box)

Hmm - can't find BHD in any of the online charts. Anyone got the spec for that needle - maybe from your Winsu dunketh ??
I can say that BDL was the standard factory spec needle for the MG Metro - which this engine is very close to - and BDM is a later slightly weaker needle also used where economy was a consideration!!
The BDL works -I used one in my 1360 Mini engine (approx 90 bhp) - but the economy is not good!

Theres actually quite a difference between the two needles you've mentioned and the BHD one.
THe BDL one looks a close match but is a lot richer throughout the rev range.

WinSU often picks 'strange' needles. I guess suppliers tend to just keep the more popular types in stock.

Anyways, heres the comparison chart from WinSU.

Yes - thanks dunketh - that's very useful. The BDM I suggested is the economy option - more and more important these days. Whatever is used will only be a starting point - road testing or RR will be very necessary!

Dunketh, would you be able to do the same for my engine spec?

Standard Bore 948
Standard 12g940 head
MG metro Cam
HIF38
Howley inlet manifold
3 Branch LCB manifold and corresponding twin box exhaust system
Standard ignition
Standard everything else!

cheers,
DB

Thanks

Errm just realised (thanks to Mr P. Tee) that I didnt include my cam in that list

I havge a kent 276 in that engine too

Cam makes quite a dfference! In fact a larger capacity/large cammed engine may well need that weaker (BDM) needle because the increased airflow through the same carb sucks more fuel out of the jet gap! Only road testing will tell. What needle is in the carb at the moment?

thanks to Mr P. Tee

Anybody I know?

I am aware of that BMC, thats why I asked for it with the correct cam!

Aye - but waht needle is there at the moment ? I'm sure you also know that the spring comes into the equation - needs to be light enough to allow the piston to rise fully in the bore - but not so light that it's up there long before the engine reaches it's peak revs! Otherwise - the mixture is then no longer controlled by the needle - and it's just a case of the airflow sucking more fuel through the now fixed annular gap between jet and needle stem. Easier to check this on a Mini - drive it flat out and look through the speedo hole - not so easy on a Minor (and revving it up without load is hopeless) - so either RR or - fix up a camera to see what's going on as you leather it up a long steady hill!

With the 276 cam WinSU suggests a BCD needle and a yellow spring.
Another suggestion is BHC which is a little richer top end but a closer match through the mid range. (And frankly, who cares about top end)

I'm surprised you havent played with your ignition though, especially given the measures you've gone to elsewhere.

Scott's WinSU does a pretty good job of pointing you in the right direction, but from Soton, you are not far from Tom Airey near Winchester http://www.aireytuning.com/.

Have been there with a couple of A(+) series Minis a few years ago and was v. pleased with the results.

Not just 'pub BHP' figures, but will talk to you about tuning to get best spread of torque, or peak BHP, or possibly even economy if that floats your boat


Well worth the $$ for a RR on a modded engine to know that you are not going to run rich and wash yer bores out, or run lean and melt pistons etc.

In my limited experience BHP figures are a load of guff anyway.
Its all about how you drive the thing and where the power comes in.

No point having a lairy cam'd-up lump with silly BHP if you can only drive it over 4000 revs.

I can't imagine a 150bhp A series being much fun idling in traffic.

Oh, how true Dunketh!

I had an engine job done on a 1272cc Polo. Schrick 266 cam, gas flowed, weber twin choke. The rolling road printout was eye popping - no suggestion it was a peaky cam. bhp up from 55 to 90. Torque from 72 to 93lb/ft. Both at comparable rpm. On the road it was a different and dissapointing story. Flat out from a standstill it was great. Below 9 secs on a 0-60 sprint (standard was 12. In every other respect it was a complete pig. The response in gear was dead. The torque appeared to have been halved and at 3000 rpm the resonance was dreadful.

Weight for weight there's not much between a (mk2) Polo and a Mog. With comparable engine spec they should go about the same.
I'd love to drive a properly sorted 1275 mog. I've been a passenger in a couple of impressive beasties but you need to be touching those pedals to know how it's responding.

Worrying about peak BHP is great if you're going to be driving flat out all the time, (track, track, track).

But for something usable then the spread o torques is yer friend

Something that will pull cleanly from about 2000 to 5000 will give more relaxing (and quicker real world driving) than a 7k screamer.

Peetee,

I wonder how much of the Polo problem was the twin choke Weber? Normally on our 1380 I run an HIF6, which gives an extremely drivable road car, good idle, but when required, fun at other times. I started with a Kent 266, and the torque was amazing, although a bit restricted on top end, so it now has a 276, which is probably about the limit to give a good performance combination.

I also have a 45 DCOE set up, and we did a back-to-back RR session a year ago against the SU. The 45 gives more power, sounds great, but the bottom end is hopeless. It runs big chokes for the top end power, which really compromise the driveability.

As always, there is no real substitute for cc's (other than turbo/supercharging), but it is possible to have quite a reasonable part of 'cake and eat it'. Will idle and potter along all day in traffic with no temperament, 1,500 rpm to 5,000+ rpm in 5th (20 mph/1000) with very relaxed motorway crusing, or 7,000+ in 1st/2nd/3rd seems quite reasonable to me? The A-Series is really a great little engine.

Anyone passing through/close to Oxford is welcome to see for themselves, but maybe not the 5,000+ in 5th part, as that was on a German autobahn!

I started with a Kent 266, and the torque was amazing, although a bit restricted on top end, so it now has a 276, which is probably about the limit to give a good performance combination

Did you loose much mid range torque?