A
Anonymous
Guest
would there be in any benifit in fitting 3 2ltr pinto carbs on an alloy head 250? not entirely sure if i want an every day car or a special sunday drives car.
The devil is in the detail with carbs. Given unlimited resources of time and research (like the amout of time I've researched carbs since I was like 9 until 35...), you can make anything work okay.
If your not using it, its better to just spend up front for a tripple DCOE 45 intake, and use the same spec emissions fittings as the 1976 to 1985 Alfa Romeo Alfetta GTV 2.0. They used three DHLA Dellorto's, and passed ADR 27A, B, and C emissions regs from 1976, 1980 and 1983.
The Weber is found in 75 to 88 hp 1600 OHC Cortinas and Capris in Europe and NZ, so it can be jetted down to run as a wild 200 hp plus machine. Any Falcon X-flow head suffers above 200 hp unless you have extra head work and cam modifications. The stock head at stock lift is only a 145 cfm affair at 25" H20 with 450 thou lift. With as much duration as the stock head can handle, there is only enough for 195 flywheel hp at 4500 rpm if you have as much carby as the engine can cope with.
The issues with the Cortina 32/36 is that it has a very heavy spring load past 2/3 rds throttle to open the secondary carbs. Three opening past 2/3rds throttle would be very heavy. You would need to increase the pedal travel, and have much more mechanical advantage to offset it.
There are a few other options on how the carbs are run. If you just weld two extra 1/75 in ch diameter flanges on the early 1 -bbl XD alloy head intake, you could use three Clifford/Stovebolt adaptors, and run the centre carb as a primary carb to half throttle, and then progressively open the outer carbs. It isn't possible to run a cut up XF carby manifold becasue the distributor gets in the way, and the bolt patterns differ in height over the six intake ports. Fitting a 46 by 93 mm bolt spacing flange on the outer tracts of the XF manifold would take a bit of work, and that is an option if youy want the stock intake.
Secondly, the Cortina Weber auto choke fouls the the rocker cover. The stock ADM electric choke is so much smaller, and fits in a very compact manner.
I'm not poo-hooing the idea. I'd rather use a bunch of side drafts any day before the Corty carbs.
If your not using it, its better to just spend up front for a tripple DCOE 45 intake, and use the same spec emissions fittings as the 1976 to 1985 Alfa Romeo Alfetta GTV 2.0. They used three DHLA Dellorto's, and passed ADR 27A, B, and C emissions regs from 1976, 1980 and 1983.
The Weber is found in 75 to 88 hp 1600 OHC Cortinas and Capris in Europe and NZ, so it can be jetted down to run as a wild 200 hp plus machine. Any Falcon X-flow head suffers above 200 hp unless you have extra head work and cam modifications. The stock head at stock lift is only a 145 cfm affair at 25" H20 with 450 thou lift. With as much duration as the stock head can handle, there is only enough for 195 flywheel hp at 4500 rpm if you have as much carby as the engine can cope with.
The issues with the Cortina 32/36 is that it has a very heavy spring load past 2/3 rds throttle to open the secondary carbs. Three opening past 2/3rds throttle would be very heavy. You would need to increase the pedal travel, and have much more mechanical advantage to offset it.
There are a few other options on how the carbs are run. If you just weld two extra 1/75 in ch diameter flanges on the early 1 -bbl XD alloy head intake, you could use three Clifford/Stovebolt adaptors, and run the centre carb as a primary carb to half throttle, and then progressively open the outer carbs. It isn't possible to run a cut up XF carby manifold becasue the distributor gets in the way, and the bolt patterns differ in height over the six intake ports. Fitting a 46 by 93 mm bolt spacing flange on the outer tracts of the XF manifold would take a bit of work, and that is an option if youy want the stock intake.
Secondly, the Cortina Weber auto choke fouls the the rocker cover. The stock ADM electric choke is so much smaller, and fits in a very compact manner.
I'm not poo-hooing the idea. I'd rather use a bunch of side drafts any day before the Corty carbs.
A
Anonymous
Guest
Triple SUs 
Cheers Steve
The more carbs you have, the better calibrated they must be, and the more sensitive to bad back yard mods.
There is no way six carbs is an easy option. The Mikuni set-up Jack Clooins was running on his X-flow was very hard to tune. That is the only option for a six carb set-up, any thing else won't work. Options like the ancient Amal, Lectron, or more modern Kehien or other motorcylce carb is fine, but you have to know how to patiently dial in the fuel and air right througout the rev range without holing a piston through a lean patch or goingover rich and wetting cylinder bores and creating significant hard starting.
The worst thing is that six carbs isn't just harder than a triple carb set-up. With needle combinations and jets and air correctors, there is 50 times the work of setting up three Webers when using a bucnh of six motorcylce carbs. There are something like 2500 needle combinations in the Mikuni carbs alone, but only about 100 valid SU needles for a set of 2" HS8's. You can custom make needle settings easily, but the Mikunis are tiny and need much more effort. Cost is an issue. Get the wrong basic size, and it'll never work well for the cam and rev range of our sixes.
There is just no basic information avaliable to make even an educated guess on what the ideal jetting is. The carbs run on about 0.5 psi of fuel pressure from a header tank, so the stock 6 psi fuel pump with kill the delicate calibration and throw another curve ball on getting it sorted. More money to spend.
We've got to face facts. Even the stock single carb is a problem to tune for 90% of us, and it takes a while to gain the skills.
Scaling up the difficulty 6 to 50 times isn't smart.
Carbs like triple set-ups (Webers DCOE,DHLA Dell Orto's and espically SU's and Stromberg CD175's), these are simplicity itself, and there are basic jeeting starts and information to draw on to make it work.
If you are prepared to grab an old engine, and experiement at the speedway or in a bush bus, you could make six of them work okay if you had time and were able to invest in a couple of wide angle oxygen sensors or pyrometers. You could invest in a syncrotester and colortune, and adjust the basic mixtures, then set up the mixtures more accurately on a chassis dyno.
There is no short -cut.
Check out these from http://xpfalcon.kicks-ass.net/Engines/Original Six.htm!
There is no way six carbs is an easy option. The Mikuni set-up Jack Clooins was running on his X-flow was very hard to tune. That is the only option for a six carb set-up, any thing else won't work. Options like the ancient Amal, Lectron, or more modern Kehien or other motorcylce carb is fine, but you have to know how to patiently dial in the fuel and air right througout the rev range without holing a piston through a lean patch or goingover rich and wetting cylinder bores and creating significant hard starting.
The worst thing is that six carbs isn't just harder than a triple carb set-up. With needle combinations and jets and air correctors, there is 50 times the work of setting up three Webers when using a bucnh of six motorcylce carbs. There are something like 2500 needle combinations in the Mikuni carbs alone, but only about 100 valid SU needles for a set of 2" HS8's. You can custom make needle settings easily, but the Mikunis are tiny and need much more effort. Cost is an issue. Get the wrong basic size, and it'll never work well for the cam and rev range of our sixes.
There is just no basic information avaliable to make even an educated guess on what the ideal jetting is. The carbs run on about 0.5 psi of fuel pressure from a header tank, so the stock 6 psi fuel pump with kill the delicate calibration and throw another curve ball on getting it sorted. More money to spend.
We've got to face facts. Even the stock single carb is a problem to tune for 90% of us, and it takes a while to gain the skills.
Scaling up the difficulty 6 to 50 times isn't smart.
Carbs like triple set-ups (Webers DCOE,DHLA Dell Orto's and espically SU's and Stromberg CD175's), these are simplicity itself, and there are basic jeeting starts and information to draw on to make it work.
If you are prepared to grab an old engine, and experiement at the speedway or in a bush bus, you could make six of them work okay if you had time and were able to invest in a couple of wide angle oxygen sensors or pyrometers. You could invest in a syncrotester and colortune, and adjust the basic mixtures, then set up the mixtures more accurately on a chassis dyno.
There is no short -cut.
Check out these from http://xpfalcon.kicks-ass.net/Engines/Original Six.htm!
TCSTEVE
Well-known member
xtaxi":2r8el78f said:
X you got me in your first line.
I did say i was feeling crazy.....but not stupid. Thanks for putting me straight on which one i was and wasnt.
Anyone got a Tripple set up for sale?? I want something different. maybe i can mod up a manifold for 3 sets of fuellies.
Cheers Steve
A
Anonymous
Guest
"its better to just spend up front for a tripple DCOE 45 intake"
Hello XTaxi,
I also, think about cuttin, drillin, millin, honein rubbin, cuttin and so on and so on all the time. A Dremel or small air grinder is one of my favorite tools. The dual carb set ups are just bitchin. Your right though in that unless you have have the time and tools, a single carb just works better. It's been proven in a lot of magizines. The exception to the rule though applies to our small sixes. Especially the US log versions. They need more air so the thought of cutting in a couple more carbs sounds appealing. And for the US motors, it works. A bunch of carbs is just...sexy.
So back to my DA, Where do you get an intake for tripple DCOE's?
Hello XTaxi,
I also, think about cuttin, drillin, millin, honein rubbin, cuttin and so on and so on all the time. A Dremel or small air grinder is one of my favorite tools. The dual carb set ups are just bitchin. Your right though in that unless you have have the time and tools, a single carb just works better. It's been proven in a lot of magizines. The exception to the rule though applies to our small sixes. Especially the US log versions. They need more air so the thought of cutting in a couple more carbs sounds appealing. And for the US motors, it works. A bunch of carbs is just...sexy.
So back to my DA, Where do you get an intake for tripple DCOE's?
Why stop a tripples, when you can have sex?
Um, six!
(Sorry, I'm A Kiwi)
With the log, you have to do the Speedway cut like the old timers did in Austrailan speedway. Befroe 250,s and 2V heads, there were Blattman and Lynx cut-off log adaptors which gave the option of SU's on Falcons. no Webers came about until the Cortiona Six of 1973, and then suddenly the odd DCOE 221 or 250 came out in oval track.
Your best bet is to cut the log as per the early practice, and place some 45 DCOE 16's on a 5 degree rake with your own intake tracts welded on. Keep the exhast tangs as the are, and cut the log in two.
Adam and others here have made detailed plans for 2V 'Faker' heads, and it's not as hard as you might thing. Basic rule is keep all the cast iron exhast as per its original design, drop in the Clifford port divider, and then make up an intake out of steel pipe like Hotrodbob's. The inner tracts are very widely splayed because the centre ports spacng is twice that of the outer ports. There is very limited space in an early round body Falcon for the 200 tripple carb 2V Weber, but the 250 is better as the carb comes up to clear the shock tower more. You then get to use stock FSPP headers rather than get stuck making an exhast as well.
Untill the Argie stuff becomes more commom, I can't think of a better option than Webers if you don't have unlimted time to tune it. Check AzCoupes posts, and see if he will do you a deal on one of his 2V Weber DCOE intakes.
Um, six!
(Sorry, I'm A Kiwi)
With the log, you have to do the Speedway cut like the old timers did in Austrailan speedway. Befroe 250,s and 2V heads, there were Blattman and Lynx cut-off log adaptors which gave the option of SU's on Falcons. no Webers came about until the Cortiona Six of 1973, and then suddenly the odd DCOE 221 or 250 came out in oval track.
Your best bet is to cut the log as per the early practice, and place some 45 DCOE 16's on a 5 degree rake with your own intake tracts welded on. Keep the exhast tangs as the are, and cut the log in two.
Adam and others here have made detailed plans for 2V 'Faker' heads, and it's not as hard as you might thing. Basic rule is keep all the cast iron exhast as per its original design, drop in the Clifford port divider, and then make up an intake out of steel pipe like Hotrodbob's. The inner tracts are very widely splayed because the centre ports spacng is twice that of the outer ports. There is very limited space in an early round body Falcon for the 200 tripple carb 2V Weber, but the 250 is better as the carb comes up to clear the shock tower more. You then get to use stock FSPP headers rather than get stuck making an exhast as well.
Untill the Argie stuff becomes more commom, I can't think of a better option than Webers if you don't have unlimted time to tune it. Check AzCoupes posts, and see if he will do you a deal on one of his 2V Weber DCOE intakes.
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