Lancia Motor Club

The planned work on the Fulvia has been moving forward at a glacial pace and I've had very little time available to get on top of the project. Any hopes of entering it in some early season hillclimbs went out of the window due to pressure of work and projects around the house. However, things are starting to look up. After much deliberation I plumped for a mild steel GP 4 exhaust from Omicron, eschewing the various stainless systems on offer from other sources. I'm very pleased with the Omicron system, it seems to be a well thought out piece of kit and came with lots of free advice, always welcome... I've sent it away to be ceramic coated inside and out, this will help keep down unwanted heat sink in the engine bay and of course it won't rust.

(http://i1091.photobucket.com/albums/i384/9JOT/Fulvia%20manifold_zpsvduwlad2.jpg) (http://s1091.photobucket.com/user/9JOT/media/Fulvia%20manifold_zpsvduwlad2.jpg.html)

To go compliment the exhaust I picked up a brand new pair of DHLA 40s on eBay. They were too cheap to turn down and from experience gained building race bikes over the past few years I reckon you can't beat a brand new set of carbs. It takes such a lot of guesswork out of the set-up process. I enjoy tuning carbs and am really looking forward to installing these on the car. As soon as the correct manifold arrives in a few weeks I'll get to work tickling it up to match the Dellorto throats

(http://i1091.photobucket.com/albums/i384/9JOT/DHLA40N_zps3zj5u4wc.jpg) (http://s1091.photobucket.com/user/9JOT/media/DHLA40N_zps3zj5u4wc.jpg.html)

I've always liked the look of those unfeasibly large Le Mans style filler caps fitted to some of the works Fulvias and last week decided to take the plunge and fit one. They look a bit brutal but therein lies the appeal. Of course they look all wrong with the filler flap in place and so I bit the bullet and had it welded over. That's it, no going back now, the Rubicon has been crossed!

(http://i1091.photobucket.com/albums/i384/9JOT/DSC_6845_zpsduprheqv.jpg) (http://s1091.photobucket.com/user/9JOT/media/DSC_6845_zpsduprheqv.jpg.html)

Good stuff Rob. You're going down a route I would probably take if I had any technical skills. Bet you can't wait to get the carbs and exhaust fitted. Like the filler and the flawless welding/repainting of the petrol flap. Look forward to more progress.

Hi Stanley,
I certainly wouldn't be over-egging my technical skills... ;D
The DHLA 40Ns I've bought are very interesting. These are much maligned and viewed as inferior to the earlier carbs. I struggled to get any objective information about these carbs until I came across this written by an anonymous carb guru on the net. This is completely at odds with the numerous 'experts' who pop up on forums, most of whom have never tuned a carb in their life, they've just heard about someone who once knew someone who had! I'd struggled to understand these later carbs until I read this;


"Type 3 DHLA40F-G-H-N-R-S models.  These are called 'emission carbs' but are completely different to the DCOE type emission carbs.  Few people understand them and often try to tune them like the early models. These carbs differ from the early types because they have more progression holes and use the idle jet to feed most of the cruise phase and low rpm/low TP area of the engine AT ALL TIMES when the main jet isn't in operation completely automatically. No jetting needed. The idle jet has a very large fixed 2.2mm air feed, you cannot tune this phase of the carburetor for length like the others, but here lays the secret...

The idle jet doesn't feed from the float bowl, it feeds directly from the main jet stack, what happens after this is what gives these Dell'Ortos the sweetest road behavior and dead easy tuning. You see, when the main jet starts to emulsify fuel in the tube, the idle jet is feeding from it, so the gassy airy fuel shuts down the idle jet and sucks backwards, yes BACKWARDS through the idle, using every drip of fuel efficiently without ANY waste in circuit cross over where one is going after the other...this happens the moment the main jet fires, so there is NO need at all to tune the length of the progression and idle phase.
This is pure magic they are automatically calibrated, you simply keep the idle jet above 59 up to 62 and not make the mistake of fitting numbers suited to the early DHLA or DCOE - with this simple technique you can tune anything from a 1300 to a 2000cc without really doing anything.
The emulsion tubes in these carbs are always 8-10-11 and have to stay that way - which are really rich and have a hole straight down with loads of air holes, these atomise the fuel to an massive degree, also they have to be used because the idle jet will not run correctly using the DHLA40-E type tubes (1-6-7-5) as the idle jet needs these airy tubes to function and cut out as designed.
Often people install the DHLA40 idle holders with the air holes into these carbs, add the 1-6-5-7 style tubes and wonder why they've got a massive lean spot off idle. It's simply because they missed the point completely!
These carbs use a .3 vent which has a very small signal tube to the main jet stack, this is because the holey tubes are basically ready to go from about 1250rpm (on my car using an 8tube 1 vent it was on the mains at 1250rpm!) so the holey tubes need holding back with a signal killing venturi...These carbs are wicked if you want bolt on power, they tune themselves!

The early types are better in respect of punch and tuneability in certain applications but dont' really do anything these late types won't do on all but the most highly tuned engines...I have run em all! These later carbs will give the maximum power available on any engine if you take time to tune them right. Be aware they are a bit more suited to standard motors , motors with mild cams or standard cams and they operate best if you are using 30-33 chokes. They hate full race engines, mad cams and mad chokes . They they are designed mainly for hot production engines with a clear pulse strength to suit the retarded venturi and tubes - great where good manners in town driving is still important, they also give superior economy to the early types.

So the DCOE is the same as the DHLA40, but the DHLA40E and F-G-H-N-L-R-S are all evolutions of a principle and provided the application is matched to the carbs best qualities you have the ability to cater for everyone's tastes and requirements using Dellorto..."

Meant to ask - why will the manifold need 'tickling up' to match the Dellortos? Are they slightly the wrong type or you just want to get it spot on?

Hi Stanley,
 The manifold is coming from Omicron and I would imagine it will be sand cast from what is known as loose patterns [I could be wrong and it might be investment cast, but I would doubt it] Sandcasting components in small batches can often introduce small variances between individual components, this is perfectly acceptable from a QC issue in this application.

On something like a manifold the port apertures will be created by inserting cores into the pattern, these effectively fill out the void and cut down on material waste and post-production machining operations. The positioning of these cores can vary slightly between castings and could potentially introduce a lip or a step for the gas as it flows out of the carb venturi. before fitting a set of carbs it's good practice to check the alignment of the chokes with the inlet ports on the manifold and remove [ie tickle ;D]any obvious impediments to the progress of the gas.
I'll also be checking how the manifold ports  line up with the ports in the head.
Investment casting would be a more accurate way of casting a manifold but the cost of tooling be prohibitive.

Be careful if you decide to gas flow the head as you can get into the waterways and head bolts esp on no.4. A bit of a tickle at the port edge though should be fine. Its the junction between the manifold and head that is important as well as the juntion with the carbs....

Also dellorto tops can foul the bonnet.....as higher than solexes.

On the topic of getting the bonnet closed:

http://www.lancia.myzen.co.uk/forum/index.php?topic=5639.0

Thanks Rob, I understand now. Back in my motor club in the UK was an ex-Rolls Royce engineer who used to do a lot of work on competition engines and inlet manifolds. I'd always imagined they'd be polished super smooth to aid airflow. In fact he said the finish was relatively rough to cause the air to swirl.

Bit of a black art that Stanley, and you're into the realms of boundary layers and laminar flow!  The theory is , if you can upset the layer of air next to the surface of object the air is flowing over, the main bulk of air will flow faster around the object. Think dimples on golf balls ...

I won't be gas flowing the head Tim, experts tell me Fulvia heads are pretty good in this respect. My main priorities will be optimising the ignition and valve timing in conjunction with the carbs and exhaust. They'll be enough mischief in that little lot without delving into the head. ;D

Lifted from the 'CUC 20H Fanalone thread:

"Jonathan has stripped and rebuilt the 48 Dellortos using comprehensive overhaul kits, checked the pump filter, overhauled the Filter King fitting new gaskets and spring, fitted a new set of points and she's running better than ever.  Smiley Another case of not knowing which was at fault or maybe it was a mix of all.

He also machine tapered the two faces of the inlet manifold which has lowered the carbs, had the radiator re-cored reducing the height by 20mm and lowered the height of the water manifold and the temperature sender. All of  which has resulted in the bonnet shutting level with the wing tops without fouling the carbs and radiator.  :)"

Robin.

All interesting stuff. So if you dimple the entire bodywork of your Fulvia with a hammer you get an extra few mph out of it!

Getting a bigger exhaust valve will help match your Gp4 manifold and get a real gain. You cannot go up by more than a couple of mm but the surface area is a square of that....

Anyone got a favourite YouTube link for an inspirational sound track?

The engine sound is quite low but you might forgive that for other aspects:

https://www.youtube.com/watch?v=hDXRnEuQgbo

Great clip!

This is the soundtrack which convinced/inspired me to start looking at the Fulvia's exhaust and induction!

https://www.youtube.com/watch?v=cGiZR23VyhQ

Lovely! This is nice too...........

https://www.youtube.com/watch?v=7qnbM6KSNns

Must stop watching................now I want to fit Dellortos etc too.

Great sound...those 1.3s can be made to go quite well!!

Got to hand it to yer man at Targa Florio classics, he hunts out and posts some great videos on You Tube.

Maybe ten years ago there was a 1300 Fulvia coupe at HSCC meetings that kept all the 1600s honest.  From memory the builder and driver were not the same guy and the builder was from near Oxford.  I can remember it hanging its inside rear high in the slow corners.  Can anyone help me out as to who they would have been and when?

David

Nobody seems to have commented about casting but the one pictured is surely welded up from tube and the manifold flange will be plasma cut steel plate to a high degree of accuracy. However, along with the rough surfaced inlet tracts, I have come across manifold flanges with a deliberate step to the ports to encourage swirl.

you pays your money and you make your choice.

The one in the picture you are referring to is the exhaust manifold, not the inlet. And yes that will be fabricated...

This is the one we're discussing, and this looks like a sandcast item to me.

(http://i1091.photobucket.com/albums/i384/9JOT/fulvia_dhla1-300x264_zpsdk7ahhlg.jpg) (http://s1091.photobucket.com/user/9JOT/media/fulvia_dhla1-300x264_zpsdk7ahhlg.jpg.html)

Hi Robin,
That's a very interesting point about machining the mating faces of the manifold. It should be possible to pinch a couple of degrees off the angle of the carbs by altering the relative angle of the manifold mating faces. A couple of degrees could potentially equate to 15 or 20mm off the carb height.
 The exact amount to machine off could be established by loosely assembling the carbs and manifold on to the head and leaving a bit of slack in the upper mounting bolts allowing the carbs to droop. If they clear the bonnet then all that needs to be done is to measure the gap, divide it by two and machine an appropriate sized wedge off each mating face.
In theory you'd only need to machine one face but it that would depend on how much meat is on the mounting flange. Machining the face which mates to the head [as opposed to the carbs] will give the most bang for your buck in terms of reducing the overall height of the carbs.
I like it!
Omicron's advice regarding the rad was a little less complicated than having it re-cored. They suggested altering the length of the upper mounting strap and tilting the rad forward a few degrees. Obviously there's no clearance issues with the rad to bonnet , it the rad to carb clearance which is compromised by the new manifold.

           
I had a Volvo 265 in 1987 which, as everyone knows has the aerodynamic qualities of a sand faced fletton. The hurricane caused a large number of tiles from the house roof to be deposited on the Volvo, giving it the required appearance of a golf ball. It made no apparent difference. If it does not enhance the aerodynamics of a 265 then I fear it will fail with everything!!!

                                 Andy

Stanley's post reminded me of the Father Ted classic when Ted planished an entire car a hammer
https://www.youtube.com/watch?v=8mdwAkWvWMw

I must admit I had that in mind too. One of my favourite lines 'I thought I had it there for a moment'.

Did Omicron give you any sort of idea of power increase from the carbs and exhaust? I take it you're leaving the cams alone for the time being?

Here's a photo of a 1600 I found. Without checking against my car, it looks as though the relationship between the standard radiator and alternator etc is all pretty standard and there's still space for the original dipstick inbetween. According to the caption these are 48's. Perhaps you won't need to move the radiator?

Stan that HF has a manifold adaptor which has different geometry.

I have a pair of 45's on such an adaptor which I have yet to fit as I like the standard 42's too much........

I like the colour co-ordinated bungee cord retaining the battery!

Interesting to note that car also seems to have adequate distributor clearance, Tim, is this due to having the aforementioned adapter?

Stanley, in answer to your query, I haven't a clue what power increases could be expected and am always skeptical about bolt-on power claims. In my experience most amateur-modified vehicles [and a few professional-modified ones!] tend to go slower than stock. This is because it's common for people to bolt on stuff which looks sexy but then fail to address the really important stuff such as ignition and carb timing, not to mention the general overall health of the engine.

The main motive behind the carb change is to make the car a bit easier to set up and optimise due to the availability of jets/chokes etc It's also dead easy to change jets on DHLA/DCOE type carbs.

If you asked me what my target power output would be, I would be delighted if I could get a 1300 Fulvia putting out a reliable 105 bhp at the wheels with a commensurate increase in torque. To me, that would be a realistic and potentially achievable objective, others might disagree.

 The general plan is to get it performing well on the carbs and exhaust and if I feel some extra power would be handy then cams and pistons are an option for next year. Small , incremental improvements is what I'm aiming for.
 

Well, the original 1.3 HF's put out 101bhp and they went pretty well.

Herewith a couple of photos of the carbs (48 Dellorto) on the Fanalone after Jonathan's modifications. The radiator is pulled as far forward as possible by the top rubber mount otherwise the large alternator which is fitted would foul the rad core. We've fitted a metal plate to the core to make absolutely certain that the alternator dosen't ever hole it!

Robin

Rob the adapter bolts onto the existing inlet manifold so clears the distributor. Jason and Louise use this on their racy 1600 Sport with good effect even though the inlet tracts are considerably increased.

Re power to wheels this would be impressive as manufacturer power is at flywheel and I have seen 15% power loss quoted through the drive train....

I'd have to agree Tim, I didn't appreciate Lancia BHP figures were quoted at the flywheel, I'd assumed the figures I'd seen for the various HF derivatives were taken at the road wheels and assumed a carefully built unit of similar spec must start to approach the factory figures.
 I shall downgrade my estimate accordingly! If we get 90bhp at the wheels I'll be very happy... this would equate to approx 15% increase.

Robin,

where's the cooling fan?

Brian
8227 8)

Brian, I think it is on the front of the radiator when I looked at Brooklands.

Thanks Neil,
didn't think of that ::)

Brian
8227 8)

Yes, that's right Neil, the fan had to go in front of the rad and blow instead of suck!  The size of the alternator leaves no room for a fan.

Robin.

Fitted one of these bad boys (the lower one) to my 1600 Sport. 19mm stiff FARB. Twice as stiff as the standard 16mm bar.

I know how it will handle as I have one on my HF.....Just waited a long time before asking for another batch to be made.....

Just for interest here's a pic of the manifold with its freshly applied ceramic coating . It's been coated inside and out which should hopefully keep rust at bay for many years. The other advantage is reduced heat within the engine compartment.

(http://i1091.photobucket.com/albums/i384/9JOT/manifold_zpsdg9n3jr9.jpg) (http://s1091.photobucket.com/user/9JOT/media/manifold_zpsdg9n3jr9.jpg.html)

Very nice !
The ceramic coating, it's a DIY job or specialist ?

Hi Simon,
The coating was done by these folks... http://www.camcoat.com/main/ their website tells you all about the process.
Bob

Just returned from 2000 mile round trip and can say this anti-roll bar upgrade is well worth it. No negatives, just positives on the handling front.

That's good to hear Tim, will one fit in the Fulvia cabin? If so I will collect the one I've ordered from Omicron when we visit this weekend..,
My GP4 inlet manifold arrived today, very tasty...

It will go in the cabin maybe even the boot...