Twin 1 1/2 v Weber

[wantafaster1]

Dear InTheShed, the road manners I am concerned with is not going to the shops but rather the behaviour between tests and stages. Something that isn't fuelling quite right is a pain in the rectum to drive if you have to contend with traffic. People weren't stupid 40 odd years ago and I'm not aware of any tuning kits supplied with a weber in period rather than larger SUs. I initially asked the question as I have never had twin 1 1/2 SUs and wondered if I would like them.

Your tartan rug comment is a bit uncalled for as I'm not into polishing competitions or whether I've got the correct thread screws holding the number plate on either. I do hate destroying good or rare stuff though so no bulkhead chopping for me.

[In the shed]

I wonder if bad manners are caused by people not setting things up properly. Clearly, if you are a bit short on your inlet tract with a long cam, or compromise/go OTT with the exhaust, it could affect low down running.

I wonder how a similarly choked Weber with a 6" manifold and 80mm trumpets would fare against a short set of HS4s. I had exactly the same word with myself. I have a 1430 with a 320 cam....so like a 1275 with a 649.....Do I cut the bulkhead or do I fit SU's? How will this affect the way the engine behaves? Sadly, with pokey cams, the bit of the curve most suspeptible to damage is the bit which makes it drivable.

I'd go for the weber and set it up properly, because you will have the best of both worlds. If you set the SUs up, you will not get the inertial ramming and will lose low down torque, no matter how others argue the case otherwise....If you play around with the cam timing to give yourself more low down power, you will compromise the ultimate performance of the cam...in that case, perhaps a properly set up 286 would be better.

As far as using correct period equipment, have a good look at the weird array of gear (particularly exhausts) which were available. I'm also very much a purist, however, something like a modern exhaust/ignition system is an acceptable upgrade IMO.

I used to drive my old rally car to work and it was a bit "testing". I think it irritated other people more than me. I did get pulled over by the police for "driving like a twat" and I said "this is how I have to pull off" (with it sat clanking away in the background). A part of the art of tuning is to set the engine up to the best of your ability and the potential of the machinery. As good as SUs may be and considering how many super successful teams used them effectively, they are inherently weaker than a weber on a long manifold. Of course, you could use a weber and a short manifold, but you'd have exactly the same problems!

[Pete]

If you are worrying about road manners, or whether to cut holes in your dash .

Worth a mention also that it's not necessary to fit an airbox to run a Weber, it's not permitted in HSCC to cut the bulkhead so they speedo aperture is usually 'nibbled' to enable a ram pipe. My Hornet produced 110bhp on Peter Morgan's rolling road (when it was running properly for once ! ) with no bulkhead mods nor airbox, not conventional and not ideal but works for me.

[foxy52]

If you are worrying about road manners, or whether to cut holes in your dash .

Worth a mention also that it's not necessary to fit an airbox to run a Weber, it's not permitted in HSCC to cut the bulkhead so they speedo aperture is usually 'nibbled' to enable a ram pipe. My Hornet produced 110bhp on Peter Morgan's rolling road (when it was running properly for once ! ) with no bulkhead mods nor airbox, not conventional and not ideal but works for me.

..my h4,s with short stub ram pipes run well with a car that has 98bhp..not as much running noise as weber-rising..that was the only consideration when my engine was rebuilt..!!..it never needs tuning since it was set up on Peter Baldwins rolling road... though I don't doubt u can get more power from webers...foxy52

[Smiffy]

Peter Baldwins rolling road... though I don't doubt u can get more power from webers...foxy52

You get more power from baldwins

[wantafaster1]

Pete, I would be interested in seeing what you have fitted, that is if its possible to send me a pic.

[In the shed]

I don't like the idea of running no air filter. Engines are expensive!

Besides, the amount of turbulence you'll get around the whole system will cause some serious restriction!

[foxy52]

Peter Baldwins rolling road... though I don't doubt u can get more power from webers...foxy52

You get more power from baldwins

yep even if he just breathed on it !!..55 years working on and racing minis most of his adult life !! a true legend.. along with my engine builder Black-Mamba off the forum .. engine builder to some of the very top guys in mini-racing..... foxy52

[pad4]

Full race 1380s gonna be wank on single venue rallies anyway , youre only really ever in 2nd or 3rd for most of the venues in the uk and thats where you need the torque so id say its 50/50 on either a weber or twin SU here , dont think youll feel the benifit of a weber here , the su's will give a smoother car in 1st, 2nd and into third anyway

why not try twin HIF's then you get best of both worlds

Plus - lets be really honest here - can you drive the 1380 fast enough to really notice the differance , if you can drive it at 110% all the time and need more then by all means weber it cause youll benifit from it - if not , go the easy route

my tuppence worth

pad

[wantafaster1]

What I really need Paul is the funds to come over and whip Jim Brindles's arse with one of his own engines weber or not lol!
Actually the last stage event I did on sealed surface lanes I got a 3rd in class and set a class fastest time against Novas on slicks. Now, I did do a tarmac sprint with the car and had, I think 3rd in class against Minis with stroked cranks and 13 inch Yokohamas, I'd say it was pulling 6.8k in top on a 4.1 diff and was within 3 seconds of the class leaders. Never did another sprint cos they kicked off about my Perspex windows, never mind that I had a sumpguard, passenger seat, fireater and things they didn't run with.
Haven't competed this millennium though so not sure I can drive any more now I'm over 40....

[pad4]

lets just whip his ass with a bonnet prop - teach him a lesson, Jims always of the SU persuasion on a rally car anyway

pas