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Who's running a single 40 DCOE?

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GeorgeOhr Nonya Business
Yes, confused, USA   USA
Thanks for the heads up Bobby. I'm gonna pull the trigger on one soon but since Moss Europe has them too (thanks Steve) I'll see if I can get Moss US to carry it. I know a couple of guys over there and they've been able to get euro stuff into regular stock when I asked them to before.

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vancouver, WA, USA   USA
I think you might be happier in the long run with at least a single 45 on that 1500. That's in lieu of dual SU or a dual 40 Dcoe. I have a single 40 Dcoe on my 1147 engine. With siamesed ports it flows well, pita to tune. I would think dual side drafts of some sort would be preferable on an eight port head. No scientific proof.
Mike C

GeorgeOhr Nonya Business
Yes, confused, USA   USA
In reply to # 1507124 by mike crane I think you might be happier in the long run with at least a single 45 on that 1500.

No need for it. Ideal venturi for it is 28-30 for my motor and rpm range. That choke size can be had in both carbs. I've always felt a 45 was too big for even a 1500. Think about the euro SUs at 1.5", that equals 38mm so a DCOE 40 should be fine for what I'm doing....not to mention I have 5 of them... winking smiley


Here, read this: http://www.s262612653.websitehome.co.uk/DVAndrews/webers.htm



Edited 1 time(s). Last edit at 2018-01-12 07:54 PM by GeorgeOhr.

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GeorgeOhr Nonya Business
Yes, confused, USA   USA
Just ordered my intake and brake stuff. I hate spending money but love buying parts for my car!

vancouver, WA, USA   USA
George
Thanks, good information. BTW, I am running 28 chokes on my 1147. Ported head, 9.5 CR, 270 cam, 4 into 2 into 1 header. But, it's still an 1147, as I am always reminded on long inclines. Please keep us posted on progress. As an afterthought, Geez, five DCOEs. That's justification for a pair right there and they look so cool whether they work or not.
Mike C

GeorgeOhr Nonya Business
Yes, confused, USA   USA
Two from an Alfa, two from the dual Spit kit and a Dellorto from the manifold that's on the car now I bought on ebay. I think I have 3 DGVs w/ 2 manifolds, the HS4s and a injector/SU hybrid thing I was making up. With the crossover I think I'll have pretty much everything made for it.

clshore Carter Shore
Beverly Hills, FL, USA   USA
In reply to # 1507189 by GeorgeOhr Two from an Alfa, two from the dual Spit kit and a Dellorto from the manifold that's on the car now I bought on ebay. I think I have 3 DGVs w/ 2 manifolds, the HS4s and a injector/SU hybrid thing I was making up. With the crossover I think I'll have pretty much everything made for it.

You've left out the various Spitfire manifolds for quad motorcycle carbs; Mikuni, Kiehin, etc.

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claytoncnc Avatar
claytoncnc Gold Member Marcus Clayton
Melbourne, Ivanhoe, Australia   AUS
Just to recap, and repeating what others have said:

Twin 40DCOE work brilliantly, (the jetting/venturi sizing article referred to assumes 1 choke per cylinder), giving fantastic torque through the range when set up correctly.
Twin SUs work very well, smooth and easy, but lose torque through the range compared to twin webers
Single DCOE on 8 port head, a compromise, that does not work as well as either of the other 2 options.

Not opinion, plain reporting on results of different options tried since 1974.

The best manifold is the crossover type, I have used this before

https://www.weberperformance.com.au/product_info.php?cPath=29_49&products_id=133

I do have jetting for single DCOE on a 1300, I can look it out if necessary

I know you have already decided on a course of action, and hope you are happy with, and will share your results.



Edited 2 time(s). Last edit at 2018-01-13 06:37 PM by claytoncnc.

GeorgeOhr Nonya Business
Yes, confused, USA   USA
In reply to # 1507313 by claytoncnc Just to recap, and repeating what others have said:

Twin 40DCOE work brilliantly, (the jetting/venturi sizing article referred to assumes 1 choke per cylinder), giving fantastic torque through the range when set up correctly.

The best manifold is the crossover type, I have used this before

https://www.weberperformance.com.au/product_info.php?cPath=29_49&products_id=133

I do have jetting for single DCOE on a 1300, I can look it out if necessary


Really, better than the SU's? Hmmmm, might have to give them a shot and go ahead and put them on. Problem is it's a stock wore out motor (I do have straight exhaust though). That's the same type of manifold I'm ordering. I think I'm close if not on the jetting already. I thought I had 115 mains but checked and have 130s. I'll go ahead with the crossover just to see and then maybe put the duals on after all just to see as well. Problem with the duals is they'll have to be spot on as they are as I'm not putting a ton of money in them. From what I've read from others using them I should be real close. If it's not too much trouble to check what yo have that would be great to know.



Marcus, which has better low end, the duals webers or the single w/ the crossover intake? Thanks.



Edited 2 time(s). Last edit at 2018-01-14 12:27 PM by GeorgeOhr.

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Born Loser Avatar
Born Loser Silver Member Matthew Taylor
Land O Lake, FL, USA   USA
In reply to # 1507319 by GeorgeOhr

which has better low end, the duals or single w/ the crossover intake? Thanks.

I think several people tried to tell you in the beginning, and you just didn't want to hear it. That's fine, just truck on with your decision at this point.



Matthew
1960 Triumph TR3a
1970 Triumph Spitfire MK 3
2012 Mini Cooper SS Convertible
2018 Jaguar F-Pace

79bluespit Avatar
79bluespit Rick Lazio
Burlington, ON, Canada   CAN
The best set up on a street motor IMO is a single carb, but not a single dcoe. Grab a 70-71 single inlet manifold, as it has larger runners equal in size to the head intake ports. You can use a stock cd150 carb, but IMO the best carb to use is the mikuni HSR 42. If you use the 42, then enlarge the inlet carb hole to 42mm. Short of fuel injection this mikuni will put a smile on your face and is simple to tune.

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