Handbag Legerra Developments

[James Doulton]

After getting the Legerra home a few weeks ago, I have been using it as my daily commute. I have done a few things to it to 'improve' it:

1) I have removed the centre console because I could not take my foot off the clutch with it in place because I have to get my knee next to the steering wheel and my calf was hard against the edge of the console. I have still got to find a place for the dials and switches that were there. When removing the heater controls I found that the outer sheaths of the cables were not fixed, so moving the levers did nothing. I don't think that the heater control works at all. So that is another job on the to-do list before next winter.

2) I have moved the main instrument cluster up about 2 inches so that I can actually see the majority of the dial face of the speedo and the rev counter. The speedo is badly out of calibration - the mile-o-meter is currently registering about  3% low but the speedo is over 25% low. How can that be? It is a Czech dial, not the original Ford one so I guess that it must have always been wrong. I just have to remember that it is 900rpm per 20mph in fifth. Moving the instruments higher meant cutting the dashboard to clear the speedo drive. I now have a gap of about 2 inches below the instruments where I could site the dials and switches from the centre console.

3) I have removed the exhaust and welded up the holes where it seems to have leaked ever since it was fitted. I welded some patches made from bits of bike tube. It was quite difficult with my arc welder but I eventually managed to fill the holes that I made too. The exhaust is still loud and tiresome - it sounds really good when I rant it, but for the other 99% of the time it is an irritation. The local stainless exhaust place will make a bespoke system for £330.

4) I have replaced the original 13" cobra alloys that had 205/65 tyres with 15" wheels from a Ford Focus with 195/60 tyres. They only just fit in the rear arches and one touches the body occasionally over big bumps. The wheels were replaced because the old tyres had very poor grip in either the dry or the wet. The use of larger wheels increases the gearing about 11% and, more importantly, increases the ground clearance over local speed bumps - the exhaust used to touch before.

5) I have removed the radiator in order to cure a leak caused by the way that the electric fan was fitted using bolts through the radiator matrix. The fan had been moving up and down and wore a hole in the front of two of the cores. As a temporary bodge, I fixed it with Araldite. I'm going to weld up a frame to hold the fan in place and fix it on the radiator mounting bolts. I have bought a new in-line thermostatic switch for the top hose.

6) I had noticed that the car sometimes pulled to the left under breaking. I have now found the culprit - a leaking damper. It seems that the leaking fluid drips onto the disk when the car is parked and the brakes pull the first time that they are used. I will have to get the unit off the car to measure it to get a new pair. I don't know whether to change the springs too.

I still need to sort out the seat and I would like to move it back a couple of inches further but I think it is tight against the bodywork.

I also want to get or make a hard top or targa top - I can't be doing with struggling to get the soft top on and off all of the time, with all of those pesky poppers and the stiff locking pins at the front.

[James Doulton]

I checked the coolant and it needed another half a litre. Then this morning I took the car out for another similar run but when I had got about a mile away from home, the exhaust brackets broke so that I was dragging the silencer along the road. I was near to my local car shop so I bought a couple of bungies and got home. That little local car shop (Patchway Autos) is amazing - yesterday I went in for a Cortina bottom radiator hose and they got it in in 2 hours and it only cost £9. They get 4 deliveries a day during the week from a huge depot in Bristol which serves the whole of the west country. 

So after doing a roast dinner for my kids and their partners, I set about fixing the exhaust and fitting my new coil-overs. The exhaust went fine after I cut off the old securing bolt and made a new bracket. The coil-overs are not fitted because they have 12mm diameter holes and the top bolt is 11mm and the bottom stud is 13.2mm. I could make up a sleeve for the top bolt but the bottom stud is welded to the axle bracket. I'm not sure how to resolve that one. Any ideas? Still, I removed (and refitted) one of the old units and measured the spring. Those fixings were a bugger and I am all achy but they will be easy next time.

This evening I went for another drive to check the cooling and it was much better - even though I pushed the car a little it didn't go above 90 C. I had to top the car up again before I went out and again afterwards. I cannot see any leaks but I am now suspicious about where the water could be going. I've checked the dipstick and I have checked around the heater, the inlet manifold is firmly fixed so. There is no evidence of a head gasket leak either but I have topped the car up three times, each time about half a litre, and that seems too much for an airlock.

[Dave Adams]

i have put ducting under and down the side of my radiator and it has helped with the cooling a lot!

[James Doulton]

Well, I've replaced the radiator. The new one is a Cortina one but with a .double core. Some of the surrounding metal was slightly different and that meant that my welded up assembly for the fan would not fit, so that needed rebuilding (welding). then the radiator metalwork was too wide to fit from below so I had to cut a hole in the under bonnet bodywork so that I could drop the radiator in from above. When I refilled the system, I found that it was leaking from the back of the water pump, so that mean fan belt and pulley of so that I could get at the water pump fixings. Then all set, so I took it for a ride.

I drove sensibly without ranting it, even though it was inviting me. I did about 4 miles and the temperature just kept rising. The car was still running fine but the temperature got to 110 Centigrade by the time I got home. The fan was working. I was pleased that there were no leaks or hissing but rather disappointed that it got so hot while just pottering.

When it cools I will check the coolant level.

[James Doulton]

Well I got my Legerra back from my local garage with a new MOT today. They had to fix a few things, including the Mk2 rear brake adjusters. I know that I should have done them myself but I have had a cold for a few days now and I have been very busy at work, so I just paid instead.

I felt rather guilty because I have only repaired one side of the chassis, so I refitted the under-floor aluminium sheet to conceal the rust - and it worked. I justified it to myself by knowing that I am going to repair it really soon. I did it because I just didn't want to let the car become a SORNed 'project' because it might never get back on the road if that happened and I knew that I could not get the chassis repaired during the crazy period leading up to my holiday.

I can't really drive the car at the moment anyway because of the leaking radiator. It overheated in the 3 miles back from the garage. I have a brand new radiator which is the same Cortina shape but with a higher efficiency double core. However, I am not so sure that was a good choice now as it is a tight fit and I have noticed that the bottom hose is partly kinked and it has been rubbing on the fan belt. It looks like it is very close to rupturing (if the radiator was fixed so the system was pressurised). I might get around to fixing that this weekend, hopefully.

[James Doulton]

I finally replaced the front dampers on my Legerra with the GAZ units that I got a couple of months ago. It has hot and dirty work in my garage and everything was so tight - I'm all aching now! When I looked at my mountings I could see that they had actually been modified before to take the wider eyes on the previous Spax dampers and I needed to fit a couple of washers to fill the 4mm gap. I had to make up some sleeves for the bolts as the dampers have 1/2" holes but the bolts are only 7/16". The damper adjustment is about 50 clicks, so I set mine soft at 15 clicks and that seems to have improved the ride quite a bit. I guess I should think about doing the back too but that'll have to wait until after the MOT in August.

[James Doulton]

The bike that my carbs came from, a Kawasaki ZX7R, produced 123bhp, so presumably the carb can supply sufficient fuel for that as standard. It has 2mm main jets. I'm hoping that the standard main jet will be pretty good for my Pinto because it is a slow iterative process to change them on 4 carbs, so it would be a very expensive session on the rolling road. I hope that by using the carbs from a similar performance bike then the set-up will be restricted to adjusting the height of the needles in the slides. CKC had an article on how one company set up a customers car with bike carbs a couple of years ago, they used a lambda sensor and filed the needles. I thought that lambda sensors only tell you how much free oxygen you have but for maximum power you need to run rich at 12.5 to 1, not the stoichiometric ratio so I don't think that scheme would work properly. I think that you'd want to measure Carbon Monoxide levels instead. We will see how I get on when I eventually get around to fitting them, maybe in the autumn.

By comparison, my Haynes Weber manual reckons that a 2l Pinto should use a 45DCOE with a 34mm venturi and a 1.45 main jet. It has figures for all of the other variables too, so it would be much easier to get the car set-up with Webers - they just cost so much to buy. Also I think they are a little bigger, so they might no fit in the Legerra engine bay.

[Dave Adams]

having owned a new pinto engine and driven it for the last 4-5 years i would say its an OK engine but not great. the kind of money needing spending on it to get over 130 hp is just daft and you end up with a shortened engine life and lousy fuel economy. Not that it was great when standard (for either life or economy).

the bike carbs look like a real alternative to webber side draught carbs, and it is very interesting the information given below.

just not sure that the effort is not wasted on a pinto though....

[Dave Adams]

had a look at that link and isolated this post.....

it has the interesting part.....

Here we go guys.....

I was right on the money with the best guess, the 40mm R1 carbs at WOT with the variable venturi fully up and everything else sealed off (vacuum lines etc) are flowing just a tiny bit more air than 45's with std 36mm choke and 4.5 aux vent, when 37mm chokes are fitted to the 45's they clearly flow more air

I also tested them again the unique ventutri's I am developing and it is very clear the 45mm carbs can flow WAY more air with better designed venturi's I am not going to say any more than what I have right now is flowing a little more air than 48DCOSP's with 38mm chokes, that is pretty epic flow from a 45mm carb which having the same bottom end power as 45's with 38mm chokes in terms of throttle response

I was surprised to see that the variable venturi's in the R1 carbs get sucked up out of the way quite quickly when the flowbench is turned on

I believe the reason why bike carbs do not have an accelerator enrichment mechanism is because with the variable venturi they simply don't need it! in truth fixed venturi's work a lot different to variable choke, both systems have their pro's and cons

For a road engine these bike carbs appear ideal, twin 40's will never flow as much as a 40mm bike carb that is for sure and at the same time 40mm bike carbs are very going to flow enough air for an engine that was needing 38mm chokes in 45mm carbs or greater, don't even mention 48mm carb flow that is in a totally different league when it comes to airflow, only the heavily modified 45's I am working on can compete and beat 48's

As for larger race bike carbs they are incredibly expensive, did anyone price them, have a look and makes sure you are sitting down when you hear the price of anything race orientated lol! mega expensive and imho not making any sense at that stage as TB's and ECU could be bought for the same price or less!

I do think that the best carbs on earth are slide throttle RACE bike carbs which have 45mm ID's, they would out flow 48's no problem and have higher air speed through them and more tuning potential, but the cost is just insane for carbs, TB's make way more sense when spending that kind of money

The advantage you would have in a road engine with 40mm bike carbs would be that they flow just a tad more air than 45's with 36mm chokes (practically the same air flow) but the 40mm throttle plates would make a more progressive throttle when driving at low speed and the air speed through the 40mm carbs is going to be a lot better than 45's with their larger 45mm trumpet ID, throttle plate bore and inlet manifold entry, getting the same air flow with a smaller CSA always means higher air speed, cylinder filling would be better with bike carbs than 45's with 36mm chokes no question about that and I would certainly expect higher mid range torque and peak power 40mm bike carbs vs std 45mm DCOE with 36mm chokes

But if we want more WOT air flow for competition engines 40mm bike carbs are not going to cut it on a high spec 2.0 pinto or 1.6 16V engine and up

42mm bike carbs would be interesting to test, they would no doubt flow similar to 45's with larger 39 or 40mm chokes I am sure and be more suitable but there isn't a hope of them out flowing the new venturi's I am working on for the 45mm carbs, watch this space as you will soon be able to upgrade 45mm DCOE's to flow the same air as 48's but with no loss of low end response and finer fuel atomisation

So now we can lay to rest some of the claims that bike carbs are as good as 48's etc and also it is clear that for fast road engines they are a very good option imho and better than some people might have thought

There is one thing that I will add about bike carbs that is very important, using an inlet manifold with port runners as straight as possible that match the head ports, the carbs can flow all the air they want but if the manifold is reducing flow and air speed then this changes the situation and they cannot compete with 45's in terms of peak torque and hp

Ideally the bike carbs would be spaced out to match the bore spacing of the engine and a simple inlet manifold made with one mandrel bend in them at most, that will give better results than using them with the original spacing that is much too narrow to suit most car engines, the straighter the port runners the better even if they flow well on a flowbench, flow and velocity are two different things, both are very important.

[James Doulton]

Another weekend with no opportunity to work on the car - I'm fixing a leaky flat roof and repairing the damaged floor beneath it. However I did find an interesting link comparing bike carbs with Webers, see post #29 in this thread 

here

Purely by chance, my Haynes Weber Carburettor manual recommends 2 x 45DCOEs with 34mm venturis for a 2 litre Pinto. In the article above, the guy finds that a 40mm bike carb has the same air flow as a 45DCOEs with 36mm venturis, so my 38mm bike carbs should match the 34mm venturis recommended by Haynes. Result.

[Dave Adams]

The cheapest power gain is to loose some lard.....and the pinto is a lardy engine another engine of exactly the same power would perform better because of the weight saving.