TR6 and triple Webers

[SteveM]

I have just got a CP car that was completely rebuilt by Racetorations in 2003 and done about 3,600 miles since. It has an unleaded head, 'fast road' cam and the original PI was replaced by triple 40DCOE's. It was set-up on a rolling road and measured at 150bhp at that time.

Now, as the number of times I have it out on the road decrease with the wet weather, it is becoming increasingly difficult to start when left for a few days, otherwise it's pretty good, hot or cold. I've tried every kind of choke setting from none to full but it seems to need to churn over for a long time before it shows signs of starting to fire. When the weather gets really cold, I expect the battery will give out before it runs!

 

Is there a knack for starting this set-up, otherwise does anyone know of a good tuning company on the Hampshire/Surrey borders I can turn to? Could probably do with a re-tune now, anyway.

Cheers

 

Steve

 

PS, it seems to drink fuel, but is that a characteristic as well? - I am well aware that I have become a modern car softie now and forgotten what it was like in the early seventies!

[Guest Wyn]

Mine runs on triple 40 webers. I've never used choke. I turn the ignition on and leave it for around 10 seconds to ensure there is plenty of fuel pumping through, give the throttle two or three pumps and starts first time. Thirsty? depends how I drive it, pedal to the metal and you just watch the guage going down, but I don't do excessive milage therefore try not to let it bother me. Try and get into contact with some rally boys in your area, they'll soon put you in touch with someone who understands webers, one of them is much better that someone who thinks he understands webers and there are plenty of those around.

 

Good luck

Wyn

[Rhodri]

Steve- the usual way to start Webers is to switch on the ignition and wait a few seconds, for the electric pump to fill the float chambers, four prods of the throttle pedal to the floor, to squirt in petrol, about 1/4 throttle and start. No choke. Once it fires you will need to keep it going with prods on the throttle until it's warm.

 

Lots of the early choke mechanisms on the Webers were not very good. However, I have a set of DCOEs on another engine. To start this I use the same procedure as above but have about half choke. I believe Webers to be a thirsty carb, but I am sure Tom and others will contradict me !!

[oily]

Hi Steve,

I run Triple 45's on my 6. Same as the guys have said. Properly set up webs do not need choke. I have tried on mine and found it does not like it. Starting, i have found the best way is to let the facet pump run until it changes note. Two short pumps of the pedal to about half travel. Turn over with about a third travel on the pedal. Once started keep te pedal at about 1200 revs to let things settle and bobs yur uncle. To start with i used to pump to much and had to turn over quite a bit. Flooded for sure. Dont forget that with the pump running any pedal movement will send gas through. Dont flood it

 

Regards

 

Noel

Edited November 5, 2007 by oily

[D1070]

My 5 is Racetorations special as well and has the triple 40 webers, the key to a quick start is to pump the accelerator 2 or 3 times when cold.

Starting when warm/hot requres more modest pumps and the engine should fire cleanly.The webers will always be thirsty if car is used enthusiastically-is there any other way?!,

best,

Laurence

[Tom Fremont]

Hi Steve,

 

Sounds like your carbs aren't primed when you fire it up. I always pump mine up ( I've got the mechanical pump used on U.S. cars which has a priming lever ) before starting after sitting for more than 1 day ( the bowls do go dry, or at least low ) and use the choke as Weber supplied them on 40DCOE18s for Lotus. I too floor the pedal twice before ignition but don't touch it until unchoking it ( about 5 seconds after starting, max ). This procedure fires in ~ 2 revs or less.

 

Once hot it starts in a fraction of a rev with no throttle. Note that my brand new engine takes a few turns more, but the same procedure applies.

 

The veteran car gets 20 mpg U.S. overall which equates to about 22-23 mgp Imperial. Never had it on a dyno but it has the P.I. cam, Racetorations head with under 10:1 c/r and a Racetorations exhaust besides the Webers. For the era and considering the cam overlap I think it's pretty good. A stock TR250 engine in the same car got about 4 mpg more ( ~3 mpg Imperial ) with lots less performance. These are O/D equipped examples, btw.

 

If you want to tweak the fuel economy you need to focus on the idle jets - despite the name they govern the fuel delivery under 3000 rpm, so for most folks they define the fuel economy of the beast. For this sort of exercise it will behoove you to do a little research. For what it's worth I'm using 60F4s in mine but I've got a unique crankcase breather set up which I believe necessitates a step richer than would otherwise be best. The standard approach is to " suck it and see "

 

Welcome to the Weber-equipped TR fraternity! It seems to be growing since I backed into them in 1994 because my emissions Strombergs weren't tuneable.

[Bald Rick]

Hi Steve

 

I've never had Webers on a 6 but have done a fair bit of work with twin cam Alfas which were often as not fitted with Webers and the prodeeure was the same. No choke, switch on, pump the pedal a couple of times to squirt a bit of petrol in, then turn over at about half throttle they always started.

 

Cheers

 

Tony

[SteveM]

Thanks a lot, guys, you've all been amazingly helpful and all seem to advocate roughly the same technique!

 

I'll give it a whirl.

 

Steve

[SteveM]

Just an update: car's been standing for a few days, went out, let the pump settle down as usual, gave 2 full strokes on the accelerator and turned the key at about 1/3 throttle. Result - started almost first rev!

What a revelation, thanks again guys!

 

Steve