air box solutions for twin Weber DCNFs on Alquati manifold

[RobM]

I have an 1800cc Scorp with twin DCNFs on an Alquati intake manifold. That is how the car came when I bought it in 2011. Air filtration is handled by a tiny pair of "Bayless Racing" 1.75 inch high paper element filters. Years later, I concluded these have insufficient air flow volume. Even worse, they are drawing in hot air off the cylinder head.

Earlier in 2020, I bought a pretty Monte Hospital air box and associated ducting to enable use of the stock air filter assembly. I was taking some measurements the other day to buy the bolts necessary to secure the air box to the carbs, when I noticed that the air box is too tall to fit under the shelf under the back window. I would need another 0.75 inch to provide adequate clearance.

TMH website makes no mention of space requirements, but they sell a Guy Croft intake manifold with short, horizontal runners that would sit much lower than my Alquati manifold (with longer runners that are angled upward). The GC manifold is a pricey $730. In looking through some old Bayless and FAZA books, I see that Alquati must have offered a metal air box of their own design, probably made of unobtainium. It doesn't look like it would be too efficient, as it is short and draws all air from the left side, making that right side carb work harder for air. TMH air box intake is in the middle of the plenum, which seems logical.

While I'm waiting for Rod and Linda at TMH to answer my questions, has anyone else has the same experience trying to fit this air box? What solution have you come up with? Did you make your own air box?

 

[lanciahf]

You might have a Beta manifold vs the Scorpion version. I've read they are different. Also the manifold at the Monte Hospital is for DCOE carbs not the DCNFs you have.

 

[RJ80]

I've read that the TMH airbox should fit with the proper Alquati manifold. Look for "Beta M.C." cast into the manifold where front-engine Beta versions say "Cremona." That said, a custom airbox has been on my to-do list for a while. It will also have to contend with the distributor for space (I've seen one period airbox with a cut-out there. Will post a photo if I can find one later.)

My plan was to just build a hollow airbox taking filtered air from the remotely-mounted stock filter. The factory mounted that filter to the driver's side of the car on our Scorpions and Series 1 Montecarlos, but S2 Montes had the same filter mounted rearwards, on the rear shelf by the rear grille. Height is a concern as well and I've thought about creating a bulge on the engine lid to accommodate a taller design. Unfortunately, as always, time and money are at a premium so I haven't made any real progress.

It all sounds good in principle to get cooler air in greater volume, but in the end I don't know that you'd really be able to feel enough of a difference (or any difference?) to make the investment worthwhile.

 

[fiatfactory]

Alquati Monte setup.

(no it's not for sale)

alquati beta setup

and yes I'd say there would be around 3/4 " difference in manifold height between a beta coupe / hpe and M/carlo manifold, they also made a manifold to suit the beta sean which is taller again.

SteveC

 

[kmead]

That is not a thing of beauty.

 

[BEEK]

does your car have a 2.0 or the 1.8 engine? the 2.0 block deck is taller and that might be the issue. I built a custom air box for a customer a few years back and had the same clearance issues. His was a 2.0 The issue is the top needs proper clearance to the air horns. That will kill the power band if you aren't careful

 

[flaviaman]

A word (or three) about Alquati airboxes for Tipo 137’s. In November 1979 as a young lad I took the train from Modena to Cremona and walked to the Alquati works unannounced where I was greeted be Sig. Alquati himself. I bought a set of high compression Borgo pistons, cams and DCNF intake setup for my Scorpion (#1153 if my Alzheimer’s ridden brain is correct), the price for all this was approx $730 USD with no receipt. The dollar was very strong against the Lira in those days and $730 was worth much more than today, still I thought it cheap.

The airbox had louvers on the RH side, when I asked Signor Alquati about this he stated this was a recent modification as the airbox could not flow enough air from the air filter can past the cut-out for the distributor. Unfortunately as supplied from Alquati there was no filtration where the louvers were. I ended up with a piece of cut down air filter from a 308 held in with 2” L brackets. Not pretty but effective.

I had a huge amount of fun with that car....

 

[Ulix]

Yes, I remember the louvered inserts on my buddy‘s Monte back around 1990.
We wondered about these letting in unfiltered air.
Also the hose connecting the left and right sections past the distributor is „interesting“.

I would much prefer the TMH airbox I think.

 

[MikeHynes]

Wow, that cutout in the filter housing looks like a great argument for distributorless ignition!

 

[Hackerjay]

Why not make your own? When I need some thing like this I make it up in cardboard and tape. Then in my case I hand it to my foreman and tell him to encase it in fiberglass and get rid of the cardboard. Easy when you own a small factory however doing fiberglass work is not all that hard and there are also many shops that do it.
Jay

 

[RobM]

I've read that the TMH airbox should fit with the proper Alquati manifold. Look for "Beta M.C." cast into the manifold where front-engine Beta versions say "Cremona." That said, a custom airbox has been on my to-do list for a while. It will also have to contend with the distributor for space (I've seen one period airbox with a cut-out there. Will post a photo if I can find one later.)

My plan was to just build a hollow airbox taking filtered air from the remotely-mounted stock filter. The factory mounted that filter to the driver's side of the car on our Scorpions and Series 1 Montecarlos, but S2 Montes had the same filter mounted rearwards, on the rear shelf by the rear grille. Height is a concern as well and I've thought about creating a bulge on the engine lid to accommodate a taller design. Unfortunately, as always, time and money are at a premium so I haven't made any real progress.

It all sounds good in principle to get cooler air in greater volume, but in the end I don't know that you'd really be able to feel enough of a difference (or any difference?) to make the investment worthwhile.

My manifold does say BETA MC, so correct for the Scorpion. However, I don't know if I have an 1800 or 2000 block. I've seen the Lancia logo cast into the block, but never checked casting numbers to verify that it's an 1800. (How would I distinguish between the two based on casting numbers?) The guy who sold the car to me said he got it with an engine that had a hole through the side. He believed that was the original engine and that my car has a replacement engine. It's possible it could be a 2 liter with an 1800 head. I'll have to check further.

 

[RobM]

Alquati Monte setup.
View attachment 40573
View attachment 40575
View attachment 40576
(no it's not for sale)

alquati beta setup
View attachment 40574

and yes I'd say there would be around 3/4 " difference in manifold height between a beta coupe / hpe and M/carlo manifold, they also made a manifold to suit the beta sean which is taller again.

SteveC

Thanks for the pictures Steve. I would like to make something like that, but with the air intake central between the two carbs, like TMH's air box. Seems like the right carb would be at a disadvantage for air with the Alquati design.

 

[RobM]

Thanks to all for your comments!

 

[BEEK]

this is the beginnings of the base for my air cleaner housing for my scorpion. I cant make the sides until it is in the car so i can determine the height I can use. I will make it as tall as i can. Even if it means I have to do a little body surgery. These cars arent worth so much much that a properly made hump or cut out will kill the ultimate value. (I do have one that I will be keeping stock) Note the heat shield below the carbs, the shield between the carbs and the cam housing. The air cleaner housing will also be covered in "aerogel" and another layer of aluminum. I will also use heat reflective paint. I will use an insulated hose to bring the fresh air in from a remote filter can. Something like the original one, but aluminum and way cooler. (LOL) then the fresh outside air will be brought in from the outside. I have 2 areas I am considering. 1 is the side vent, which was originally used as a cabin air inlet/outlet. the other is tbd. The whole goal is to bring cool air in for combustion.

 

[RobM]

You might have a Beta manifold vs the Scorpion version. I've read they are different. Also the manifold at the Monte Hospital is for DCOE carbs not the DCNFs you have.

They have two styles of air boxes, one for DCOEs and another for DCNFs. They look quite different.

 

[RobM]

I verified by measuring the stroke that I have an 1800cc engine. As I said above, the Alquati manifold states BETA M.C. Did they have one specifically for the Scorpion? It seems like I'll have to make my own air box. No problem, just a matter of finding the time.

 

[RJ80]

I verified by measuring the stroke that I have an 1800cc engine. As I said above, the Alquati manifold states BETA M.C. Did they have one specifically for the Scorpion? It seems like I'll have to make my own air box. No problem, just a matter of finding the time.

They are one and the same. I have the Beta M.C. manifold on my Scorpion as well.

I do remember the late, great Guy Croft saying that even the TMH airbox is not optimal (too short) and therefore robs some power. A custom solution is definitely the right solution if you're serious about optimizing airflow. Keep us posted on your plans, I'm sure many of us would love to see what you come up with when you find the time.

 

[Rupunzell]

Something to consider with any air box, distance between air horn or velocity stack to top of the air box. If there is not enough air space between the air horn / velocity stack air flow will be affected in a negative way. Adding to this problem, intake runner length (including the carb or injection runner) has an effect on power band area. Longer tends to favor power at lower rpms, shorter tend to favor high rpm power.

~IMO, make the air box as needed with a LARGE air filter (much about surface area) from a production car.

At this point in the process of getting# 209 back on the road, the cylinder head is back from the machine shop.. Initially the idea was to just make it go, project creep happened. The initial single DCNF carb on a stock intake became looking for a twin DCNF intake manifold.... to not much avail. Current idea is to make a twin 45 DCOE intake manifold for the 2.0l Lampredi twin cam. It's been done more than a few times, except the problem of an air box and intake runner length is very real. The set up might end up with a "U" bend to gain intake runner length to aid in lower RPM performance. Will try to figure it out once the twin 45 DCOEs are in place.

Depending on how this Lampredi TC works out, it is still a mid-way plan for the power train. If all goes well, a different power train could end up in# 209.

Bernice

 

[stradale67]

A question for BEEK: I am fitting twin Weber DCNFs to my Monte... where did you source the bell crank arm for the cable linkage?
See photo. Item next to spring on far left

.

Thanks for your help.

Mike

 

[BEEK]

A question for BEEK: I am fitting twin Weber DCNFs to my Monte... where did you source the bell crank arm for the cable linkage?
See photo. Item next to spring on far left

.View attachment 53962

Thanks for your help.

Mike

I am trying to understand the exact part you are asking about. The linkage is basically a stock linkage assembly. The rod that goes to the carbs came with the set up many years ago. I took this off a salvage car i bought. Monday I will look deeply at the parts and see if anything is other than modified oem parts and get back to you. I have been busy teaching and have not progressed with this project in a long time. It still sits on the lift in the shop.