Lancia Volumex tuning ideas?

[Richard Knowles]

Guy,

First off, thanks a lot for this great website, my family having owned quite a few great Italian cars, it's great to browse through the site.

secondly my question, I currently got an old 1982 Lancia Volumex, I don't know the engine well and I mostly use it for transport (between the Ducati and the Delta) I was thinking of playing around with it to release a few extra bhp or torque, what would you advise me to do or should I leave it as is??

Any help would be appreciated

[Fingers]

Hi there, the best thing to do would be to get a copy of Guy's book, I know, easier said than done. It's given me a lot of useful information and let to the mods I've done on my Volumex.

I have fitted Guy's sidedraft manifold and a 45 DCOE, a smaller supercharger pulley from banned ( I don't think they're still operating) and finally one of Guy's IIIA cams on the inlet side only. If you do both it'll just pump fuel out the exhaust, which on my car has two straight through mufflers. I've had the carb properly jetted by someone who really knew what they were doing, very important.

The extra power and torque is fantastic, best on the open road and through the windy hill roads here, as you know the VX has longer legs than other Betas, not so good on the track, my friend here with a Ginetta G15 almost beat me, and it's got a Hillman Imp engine. Although it does handle much better than my car.

It's given the car the power it should've had from the factory in my opinion, I can't keep out of it, and yes it is thirstier around town, but not much worse on the open road.

I've driven in most directions from Johannesburg, and wished I had the Lancia on many of the trips.

I hope this helps, I may just sound overly enthusiastic about the car but it really is that mch better.

[Guy Croft]

Briefly: The picture below shows my conversion setup with Weber 45DCOE carb and Weber linkage, as close to a bolt-on mod as I do for any engine and + 25bhp or so increase. That said the radiator has to be shifted over but that's fairly easy. 45 or 40 carb? Well, Tom McGaffigan (USA member here) went for a 40 carb (featured in GC book) and got excellent results in his Lancia MonteCarlo conversion, I just happened to use a 45 carb the first time I ever did a conversion, and stayed with it because it worked fantastically well.

I think the 40 probably has the edge up to 180 bhp on low-end torque.

Low back pressure silencers are essential and small chokes (opposite of normally aspirated tuning). For tuning the carb refer to me, setting them up without real prior experience is not recommended. I have read of some people 'drilling out jets' etc because they could richen the mixture etc, massive pump jets, all nonsense, it's not done that way.

[Richard Knowles]

Thanks a lot for the help, I think I will be ordering some stuff shortly.

[Fingers]

Funny you should say that about the jets Guy, the guy that set up my car has large pump jets in it, 90's I think. He put a gas analyser up the exaust and drove it around until the mixture was about right. I've got the jets he installed written down at home, will let you know what they are and see what you think.

[betabob]

My first post here, but what a great forum to lurk on!

I've just noticed this thread and it almost answers my questions.
I was thinking of upgrading to a Weber 40DCOE carb and Weber linkage soon as I've always had problems with the standard setup.
Guy, could you sell the Weber carb already set up for use?
Also, any idea where I could pick up a smaller blower pulley from these days? It'll be installed in my VX coupe - other mods already undertaken include Leda adjustable suspension, CSC exhaust manifold, drilled and grooved brakes.

I was about to say I'll post some pics, but just remembered we were featured in the November issue of ClassicCar magazine if you've got a copy around. I'll scan it and stick it online as soon as I get chance anyway.
rob

[Fingers]

This is the jetting in my DCOE I'm worried it may be way off. The car runs well, no dead or flat spots, it gives the right results on an exhaust gas analyser, but it's pretty thirsty. And just what you've siad about the pump jets not being too big has me wondering.

Mains 165
Air correctors 100
Accel pump jets 70
Idle jets 35
Spill valve closed
Emulsion tube F15

[Guy Croft]

Fingers - hi

Vx jetting on that setup:

Firstly you absolutely categorically MUST use a 4-1 header with two large capacity straight thru big bore (2.5") silencers.
Pretty well anything else will make it almost impossible to jet up, far less make it perform as well as it can. OK - You might get away with a 4-2-1 header but it would need to be a very good tubular one. i'd want to see the spec. Blown engines are super-sensitive to ex back-pressure. If you're not getting a really harsh 'tearing calico' ex note under load from about 3500rpm, you've way too much back-pressure. Looking at your jetting I'd guess either you have the latter, or the chokes are too big. The a/c on any installation will generally be way bigger than the main jet. (Check out my notes on James Bowen's X19 carb thread)

That 45 DCOE jetting is totally wrong. This is where you should start:

Chokes 28mm with 3A inlet cam (maybe 30 but 28mm safer).
Main jets 150
Emulsion tube F16
air corrector 175
Pump jet 55 (and release the spill back)
idle 60F9
needle valve 225
fuel pump Facet Silver Top max line pressure 4.5psi

Change to that and things should start to make more sense.

GC

[Fingers]

Fantastic, thanks very much. The 4-1 exhaust is top of my list of things to do. Currently it's the standard header with three straight through resonators. I'll sort the jets and get it on a rolling road.