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Discussion Starter #1
Why are they mounted at about an 8 degree angle? The twin cam head is wide so I can't see it offers a lower hood. Oil pickup maybe? Restoring my old sports/racer with Alfa 1600, the engine would fit better upright. It has a modified conventional steel sump, not the bat wing.
 

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Weber clearance on the RH inner fender well, and header clearance on the steering column on the Veloce cars only. Special engine mounts and the Veloce sumps are angled compared to the one piece cast aluminum Normale sump.
 

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Discussion Starter #4
Thank you very much for your quick replies, very helpful. Sounds like I can modify motor mounts a bit and mount the engine the way I like.
 

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Do the carbs currently sit horizontally, the inlet manifold angle compensating for the engine tilt?
Will making the engine horizontal tilt the carbs instead and mess with float levels?
The sump bottom would sit horizontally now too. Will messing with that hurt oil pickup?
Just a thought...
 

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Do the carbs currently sit horizontally, the inlet manifold angle compensating for the engine tilt? Will making the engine horizontal tilt the carbs instead and mess with float levels?
Yes, I suppose it would. But when you are re-engineering your drivetrain mounting, lots of things (e.g. how the gearshift comes through the tunnel) are going to require attention - float levels will be the least of it.

The sump bottom would sit horizontally now too. Will messing with that hurt oil pickup?
On a stock Alfa oilpan, the sump bottom does sit horizontally. The oil pan is slightly wedge-shaped. betamark says he has a he has a "modified conventional steel sump", so maybe those modifications take care of this.
 

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Discussion Starter #7
Thanks again. The 40's will sit properly, I may have to mess with the float levels. I will slice and modify the oil pan, should work out ok. I will probably have to fabricate some front engine mounts, but that is doable. The transmission cover needs to be replaced so I will have to fabricate something. The car is an old sports/racer so the interior and mounts are pretty much whatever I want to make them. Rotating the engine to level means the starter will intrude a bit more into the foot box, car is RHD and steering column clearance under the carbs could be a bit of a problem.
 

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I would lower the engine in your car and you want the Webers to be level or you might have carb problems. I also wonder why you used a 1600 instead of a 2000 engine in your sports racer?
 

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Discussion Starter #9
When I bought the car in in 1969 it had a 750 series 1300, the serial number indicated it came from a 1956 Alfa. The cowl to the rear of the engine compartment had been terribly hacked up to fit the engine. The frame rails showed evidence of an earlier engine. The 1300 would run and I drove the car on the streets (it was cop bait) for several years, but the block was cracked. In the mid 70's I purchased a wrecked TI for the engine, the current engine. I installed a quick roll bar and used the car for autocross and hill climbs in the 80's. I used Formula Vee tires which gave the car much better cornering, but the additional strain on the suspension led to breaking of expensive to replace components; halfshafts and stub axles. The additional cornering forces also caused chassis flex and the cracking of the aluminum body. I managed to win TTD at a statewide autocross in about 1984 in Montana the year nobody fast showed up. Just for fun I did a few Pro Solo's with it. I guess that is the long way around on why the 1600. It really does not need any more power. I've had it to 5500 rpm in 5th gear, it gets there quickly and you are really moving in a car this size; wife, two kids and a mortgage, I backed out. The car was unused for a few decades, I have stiffened the chassis, repaired the body and installed a proper roll bar. I will be autocrossing again but with skinny radials 155X15's. The suspension components; ENV diff, transversal leaf strings, magnesium wheels, cast rear uprights are Cooper from the early 50"s. No idea who built the body. Well, there it is, more than you probably wanted to know.
 

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Discussion Starter #10
I checked measurements. When the carbs are level the engine will be canted 2.4 degrees, that should help. If I really need to have it a 0, I can have some wedge aluminum plates manufactured. Again, thank you for your help and suggestions.
 

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Engines tilted different amounts. In Giulietta days, Normales were more vertical, Veloces more canted to make room for carbs. 105/115 cars generally are all the same, but they are some major outliers like the TZ and TZ2, way canted over. So it can work, but you have to think about carb level and oil pick (and oil surge and drainback).
Andrew
 

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Weber published a spec noting that the DCOE carbs should be angled up at least 5 degrees. I recently read that Weber rescinded that spec, but I have yet to find any documentation. They noted the recommended tilt for many decades.

There is conjecture why they made this recommendation, but again, I’ve never seen factory documentation on this point.

Why do you state level would be “correct”?
 

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Discussion Starter #14 (Edited)
I found my Haynes manual on Webers "thru 1979". It states "...it is permissible for the carburetor to be inclined upwards 5 degrees from horizontal; the angle being measured from the engine side flange face through the centre-line if the barrels." What is odd is the drawing on the next page shows the 5 degree line upwards from the center line of the barrels to the throttle shaft, I guess the illustrator got it backwards.
 

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I found my Haynes manual on Webers "thru 1979". It states "...it is permissible for the carburetor to be inclined upwards 5 degrees from horizontal; the angle being measured from the engine side flange face through the centre-line if the barrels." What is odd is the drawing on the next page shows the 5 degree line upwards from the center line of the barrels to the throttle shaft, I guess the illustrator got it backwards.
My time with Webers started in the early 70’s, when I worked for BAP/Geon, which at that time was the sole US importer. The factory documentation didn’t use the word “may” for the inclination, it said “should”.

Whether one or both of those words were correct translations, I dunno. I’ve seen installations of more and less than 5 degrees that worked ok. Nevertheless, changing the angle of the engine installation in order to achieve a flat carb angle would be flawed thinking.
 

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Discussion Starter #16
I engage in plenty of flawed thinking but not so much in this case. I want to get the engine to a more upright position so it fits better in the car, that is my primary objective. The carb situation can be dealt with as necessary. If I can get the engine to a more favorable position within the operating parameters of the carb, that would be best and least expensive. But if not then I will have to shim as mentioned above.

At this point, as Ranz mentioned earlier, I should be concerned about oil pickup also.

Years ago I purchase a set of 40's and an intake for my Triumph TR4 from the BAP/Geon in Billings, MT. I had them on the TR for several years, I could never get them to operate properly at the elevations I traveled; sometimes sea level, the midwest, Billings at 3100', Beartooth Pass at 11,000" and Yellowstone Park at 8000'. I went back to using the SU's for flexibility, the Webers were great for autocrossing though: good power and instant throttle.
 

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We have been chasing issues with Webers on our old 2000’s (cast iron) for decades. These cars originally came with two morphidite Solex two-barrel carbs that couldn’t decide if they wanted to be two-barrel or one-barrel carbs. Changing to Webers looked like it should be easy, but wasn’t.

The Solex were mounted horizontally, and were infamous for dribbling fuel onto the frame structure below, peeling the paint, and leading to rust. Installing Webers directly onto the Solex manifold was mechanically easy, but required major steps to get even passable driveability.

A bespoke “Weber” manifold is now produced for these cars, and works beautifully. It tilts the carbs slightly upward. I doubt that is a major element in making the carbs work, but I don’t have fuel pouring out into the engine bay.

There is a long history of.... interesting.... Weber installations on Sports racers. I once saw a picture showing a manifold that appeared to place the carbs a foot or more away from the engine. Performance was reportedly great. Close mounting may have been more dictated by wheel well clearance than airflow dynamics.
 

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There is reasonable thinking for having Webers tilted s l i g h t l y toward the manifold today, and probably yesterday as well. All DCOE's and other carbs as well, on engine shut down, suffer a bit of heat-soak from the hot engine as it cools. This can cause some fuel expansion, particularly today, with gasses like iso-propane and iso-butane in the mix for FI. As carbs are not sealed-systems like FI, this goes "somewhere". Webers perfectly level measured at the bottom cover, with correct float settings and filled with modern fuel will ooze or drip fuel on hot shutdown. Years ago, Alfa wanted that in the manifold, not the cold air box, or with stacks, not on the lower part (starter motor and solenoid) on the engine inlet side. It's WORSE with modern "fuel", where the condition can be a fire hazard. On my own race-engines-on-the-street, when I park after the engine is HOT, I'll open or crack the hood before a hot re-start as the evaporated fumes under-hood are plentiful! Under hood fires are never good entertainment.
Alfa fitted drains to cold air boxes and Normale manifolds years ago when gasoline was in use. Todays fuel is more hazardous. A little DCOE tilt toward the engine is a good idea. This is only my opinion from my own experiences. I don't like the "whUMP!" sound of fuel ignition under hood on restart of a hot engine.
 

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Gordon--good comment.
Did not have that concern when I started my Giulia Spider at 49 below F.
In the horrendous cold of Winnipeg in 1966.
:)
 

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Discussion Starter #20
Thanks Gordon, this is all making more sense, now I know what I cannot do. Thank you all for your help. I know how to proceed.
 
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