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View Full Version : weber carb setup anyone ?



chev355ci
11-22-2004, 07:26 PM
i have a sbc weber carb setup (48ida)x4 im going to install on my camaro this coming spring after paint job. has anyone run these before
to roadrace or otherwise ? any info would help or tips. alresdy have a
sync meter and weber book,but am working on linkage. anything
would be great. thanks and great board !

David Pozzi
11-24-2004, 08:33 PM
I have them on my Lola T-70.
What manifold do you have? Moon, McKay, Inglese?

chev355ci
11-26-2004, 06:15 PM
its a moon manifold,

David Pozzi
11-26-2004, 08:49 PM
What vernturi diamiter do they have? There might be a raised number on the venturis (chokes)
Do you have any throttle linkage?
Do you have any questions?
David

Twin_Turbo
11-28-2004, 12:53 PM
I have a custom Dellorto DCOE side draft setup but I used to have 48 IDF downdrafts.

If I can give you a good advice, do not use the unisyn for synchronising those carbs. Get a 5 column water manometer (bike stores usually have those) as they are much more accurate than the unisyn.

Webers are a good choice, the jets, holders & stuff are pretty plentyfull (unlike dellorto stuff), RedLine Weber has all the stuff you need.

Larry Callahan
11-28-2004, 01:49 PM
Does it look like this pic below?

If you ever decide to sell it I'd love to get my hands on another Moon manifold.

Twin_Turbo
11-28-2004, 02:45 PM
It kind of looks like that but it's not the same. It's not a moon manifold but a custom cast piece. (It's also 1 piece, not like the moon one 3 pieces welded together, a bottom and 2 sets of runners)

Mine has more spacing between the front & rear runners and I have a pedestal in the middle that holds the linkage. I would have posted a pic but my server hosting it is down at the moment.

Twin_Turbo
11-28-2004, 03:43 PM
It's back up
https://static1.pt-content.com/images/noimg.gif

https://static1.pt-content.com/images/noimg.gif

Larry Callahan
11-28-2004, 04:24 PM
Pretty cool! Thats going to be wild!

I need to find some better shots of mine.

Twin_Turbo
11-29-2004, 04:39 AM
Oh NICE throttle bodies, are those TWM or luninention(SP?) ? I have always wanted a set of those but they are $$$$$.

Here's a pic of a setup one of my buddies runs, the filters have been changed since for custom made billet airboxes w/ long square filters.

https://static1.pt-content.com/images/noimg.gif

BRIAN
11-29-2004, 11:15 AM
Larry, I think those manifolds are obtainable from any of the Weber dealers or maybe even Moon themselves. Try Inglese they even have them on their website.

chev355ci
11-29-2004, 05:57 PM
they did have 45mm chokes but i installed 42mm.the linkage i have is the interconnect between the pairs connecting them.i am trying to figure how and where to mount a bellcrank on side to actuate by pull throttle cable.also air filters are another issue,the K&N's seem to need cutting on the base to clear each other at front to rear pairs.know of any other options besides single foam or the Lynx's ?
dave-do they work and respond as well as the say?did you add the third idle progression hole to help of idle response?
thanks

David Pozzi
11-29-2004, 06:25 PM
I have 45 chokes in mine, they came with 42, some came with 38's, the Moon setup has the carbs sligntly closer togther than my McKay manifold.
42 is OK for a street engine if you don't rev over somethinglike 6000. If you have good flowing heads and will rev to 7000 I think the larger chokes are needed.

Here is some throttle linkage setup info I posted to another site a while back:

Take a good look at the throttle linkage, it should pull from the middle between the front and rear carbs, not the front or rear ends of the manifold, the soft brass throttle shafts can easily twist due to too much load. Make sure the idle speed screw you use is on the throttle arm nearest the throttle cable attachment. Let the other 3 carbs hang on the linkage so when the cable is pulled, the play or flex in the linkage does not change, and throw the carbs out of syncronisation. Attach the throttle return springs to the throttle cable attachment, not the outer ends of the carbs.

When you attach any linkage to the carbs, do not hold the opposite end of the shaft, hold the end you are working on or the shaft can be twisted. A twisted shaft will show up as a vaccum variation between the front and rear barrel of a carb. You can twist it back to even the vaccum readings up.

don't use over 2.5 psi fuel pressure. I use the Holley Red fuel regulator but it can allow the pressure to creep up at idle and when downshifting into a turn, because I use the old Bendix impulse style electric fuel pumps that pulse a lot. I added a Hilborn type fuel injection spring loaded relief valve set at 2.5 psi that helped a lot.

If you want a pick of how my linkage is set up, send me your email address.

The carbs are very responsive if set up right.


Larry, would you be interested in a similar manifold but with larger ports? I think they are made for 58mm Webers so have a wider bore separation. Some were used for fuel injection as this one was.
https://static1.pt-content.com/images/noimg.gif

kmracer
01-01-2005, 09:54 PM
:hail: how much do one of those setups cost? that would be cool to have...

David Pozzi
01-02-2005, 10:22 PM
This one is very rare, was a GM prototype with a /00 part number. It was used by Mickey Tompson on a Stock Block Indy car, and used as a side draft weber manifold on the old Cheeta's. Was also used on old Can-Am cars in 65 up until fuel injection took over around 68.

I had heard some were going to be re-cast outside the US for vintage racers. If there is some interest in these, I'll check into what it would take to get some of them.

I'd expect the cost to be $1500 or so, but that's just a guess.

David Pozzi
01-02-2005, 10:30 PM
Here is the same manifold casting but with 58 webers in a Cheetah.
The FI nozzle bosses are used for carb linkage mounts.

Larry Callahan
01-17-2005, 09:25 PM
David, Sorry I took so long to reply.

Pretty cool manifold. I like the fact that the butterfly doors are part of the manifolds. Any idea who makes these? I could do away with my throttle bodies?

Larry


I have 45 chokes in mine, they came with 42, some came with 38's, the Moon setup has the carbs sligntly closer togther than my McKay manifold.
42 is OK for a street engine if you don't rev over somethinglike 6000. If you have good flowing heads and will rev to 7000 I think the larger chokes are needed.

Here is some throttle linkage setup info I posted to another site a while back:

Take a good look at the throttle linkage, it should pull from the middle between the front and rear carbs, not the front or rear ends of the manifold, the soft brass throttle shafts can easily twist due to too much load. Make sure the idle speed screw you use is on the throttle arm nearest the throttle cable attachment. Let the other 3 carbs hang on the linkage so when the cable is pulled, the play or flex in the linkage does not change, and throw the carbs out of syncronisation. Attach the throttle return springs to the throttle cable attachment, not the outer ends of the carbs.

When you attach any linkage to the carbs, do not hold the opposite end of the shaft, hold the end you are working on or the shaft can be twisted. A twisted shaft will show up as a vaccum variation between the front and rear barrel of a carb. You can twist it back to even the vaccum readings up.

don't use over 2.5 psi fuel pressure. I use the Holley Red fuel regulator but it can allow the pressure to creep up at idle and when downshifting into a turn, because I use the old Bendix impulse style electric fuel pumps that pulse a lot. I added a Hilborn type fuel injection spring loaded relief valve set at 2.5 psi that helped a lot.

If you want a pick of how my linkage is set up, send me your email address.

The carbs are very responsive if set up right.


Larry, would you be interested in a similar manifold but with larger ports? I think they are made for 58mm Webers so have a wider bore separation. Some were used for fuel injection as this one was.
https://static1.pt-content.com/images/noimg.gif

David Pozzi
01-17-2005, 10:38 PM
Larry,
Yes, no throttle bodies needed which would save space and money.

I checked with my contact and this is not the manifold that they are going to reproduce. they will do a downdraft weber manifold reproduction of the McKay manifold.

This one is neat, the only flaw is the runners get a little narrow where they cross each other, but can be ported bigger there, when you turn it over the bottom view looks like "folded fingers" if you get what I mean...
this manifold has a -00 GM part number so it's a GM prototype, was used on road race cars Like Lola T-70's McLaren's and the Cheeta, and Mickey Thompson's indy effort.

L78396
01-16-2006, 01:23 PM
David,
I'm new to the forum but have been reading your messages about the 00 GM prototype weber manifold. I'm planning on building a 63 Corvette Grand Sport Replica. They came with the 00 prototype manifold and 58mm DCOE Webers. I would love to know where I could get the complete setup. This would be the bomb for my project, to make it as authentic as possible. Any help would be greatly appreciated. In the future, I will need some advice as to what suspension parts to use and how to best set it up for road racing.
Darrell

David Pozzi
01-16-2006, 08:21 PM
There is another manifold that was used on the Grand Sport Corvettes. The difference is, the runners run parallel in pairs, not alternating like mine or the Moon version. They don't have the restriction where the ports cross but have a little more angle to the pairs.
This pic shows the GS mainfold, the throttle bodies are Hilborn. A 58 mm Weber side draft carb will also bolt on, and was used on this type manifold, but may need an adapter.

Damn True
01-17-2006, 12:07 PM
That is way cool!

David Pozzi
01-17-2006, 08:11 PM
True,
I've crused the net looking at cool intakes! :)
Here's a Gran Sport web page:
http://www.racingicons.com/gs/gs002.htm

Here's a cool injection pic I took at a vintage event, the car was parked under a red canopy and it added a red tinge to everything.

https://www.pro-touring.com/forum/attachment.php?attachmentid=1821

Twin_Turbo
03-08-2006, 03:19 AM
nice, a crower w/ lucas injection..very cool. do you have more pics of stuff like that? I'm collecting pics of IR intakes as well as the intakes themselves(I have a crower injection setup) also.

Impala58cvt
05-15-2006, 07:56 PM
Hi All,
I have a 1963 Chevy Weber crossran intake manifold that Chevy ran on an Indy car. I am looking for info. Mickey Thompson got involved with this design somewhere in time and the Moon Weber crossran was developed from it. This mainfold uses the 1963 Rochester F.I. base and has individual runners welded to it that cross at the top. It sits about 16 inches tall from the top of the engine block. It's about the same size as a 60s or early 70s dual qual tunnel ram. The extra height was needed to clear the headers. 58 mm Webers were used and it looks like the Moon Weber crossran but 8 inches taller. Does anyone have any info on this.

Thank You
Tim

David Pozzi
05-28-2006, 10:07 PM
Do the tubes cross each other in alternate order. IE the LF cyl, then RF cyl, then second left, then second right?
Like this? Yours might be a prototype to this manifold. Kinsler built a lot of manifolds based on the GM fulie manifolds. It would have an index pin hole in the distributor base hole.
https://static1.pt-content.com/images/pt/2006/05/GMmanif-1.jpg

Or do they cross in pairs, two left, then two right.

David Pozzi
05-28-2006, 10:44 PM
Here's some nice intakes, too bad the chev one is only 50mm, a bit small, 2 inches.
http://www.verycoolparts.com/Stack.htm

Impala58cvt
05-31-2006, 06:23 PM
This manifold has alternating order runners. There is a picture of a manifold on that looks like it on the 1st page of this thread. I think its a blue Vette with a Moon style manifold, mine is just taller. My manifold i think is made out of Alu. and it is not 1 piece cast made. I took it to Blower Drive Service where there do lots of retro work on old 1 off types of manifolds and the owner told me that he remember that style and setup running in the early 1960s at Riverside Raceway. When i aquired it years ago the owner called it a "Mickey Thompson Ram Jet mainfold" and told me the story about the Moon and M/T history. Also i got 2 sets of short velocity stacks with butterflys and linkage that bolt to where the Webers were. They were made by Kinsler because someone wanted to convert this to F.I. along the way and never did it. The linkage is newer but the stacks look older. It might be made by Kinsler as David has suggested. I am confused about the index hole. Is there a hole in side of a hole? I can't see anything that looks like an index mark. How do i measure or figure out what kind of Weber will fit this?
Thanks
Tim

Impala58cvt
06-01-2006, 06:10 PM
I took a look at my manifold today (its been since the 90s that i even picked it up) and i noticed a milled slot about 1/8 inch thick and 1/4 inch long that starts in the dist. hole and goes toward the front of the block. I would of filled it in to prevent it from leaking oil, thats if i every saw it. Whats it there for? Do all Rochester F.I. bases have this slot or just the ones that Kinsler used. I also forgot that the base has the Snowflake Foundy cast into it.

Impala58cvt
06-16-2006, 06:31 PM
Any one with more info on this Manifold?