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So I've been reading old threads about Weber IDF carbs and the "Cain" manifold. What happened to this concept? It appears that there aren't too many people who have done this in a Pantera. I don't know if it's for me or much about it, but I'd like to learn more.

Corey
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With gas prices rising steadily, and my plans to drive 6018 all around North America, I have reservations about using IR induction. Theoretically if a person restrains their right foot, the fuel mileage shouldn't be too bad. But it never seems to work out that way.

The manifold is available, but priced much higher than what the manufacturer (Aussie Speed) originally quoted.

Aussie Speed 351C Weber Manifold

Weber IDF

-G
No IDF, nor a Cain manifold, but might give you an idea how things might look like Cool

Little Weber manifolds are cast and machined these days, which might influence the price in a for us negative way. Prices went up at the time I ordered mine, and had to wait months for the next batch to be cast.

Been considering injection too (Weber like ITB's), but went for the real 70's thing after all.

Custom build by Jim Inglese ( http://www.jiminglese.com/index.html ).

Paint is a 68 Mustang color, called "Sunlit gold". Some details changed to as the original kit was (like the stacks and fuel lines), and some more still will be changed (like the linkage set-up). Images of the kit with the original stacks can bee found on Jim's site.

I did not install the kit yet - it stays on the shelf waiting for a new engine to be fitted on Big Grin



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The reason, I think, you don't see virtually any 32 IDF Clevelands running around is because 32's are way too small for a 351.

Individual runner manifolds have much different cfm demands then a single plenum intake does.

Throw away that Holley cfm chart for IR's.

The 48's were really developed for Shelby's 289 Cobras.

They start to show restriction issues at around 5,500 rpm's on a 289. That's with 42mm chokes too.

58mm IDA's were actually developed specifically for 427 comp Cobras. Not many were made. Some say only four complete serial numbered sets.

The 351c under comp demands needs something like a 54 of 55 mm throttle. Actually the number is probably the size of the intake valve seat opening or there abouts?

54.6mm, plus or minus, is the maximum the 48 IDA manifold ports can be bored out to and realistically the Hall manifold is the only one available.

That manifold has about that limitation of porting as well.

There are two other IDA manifolds that were made for the 351c that I know of. The Holman-Moody, and the Detomaso lettered one.

Hall was the only individual I know of that had a DT manifold. Years ago I wrote to DT inquiring and I still have the letter somewhere but the entire setup from them was about $865, circa 1980. Coulda', wouda', shouda'. Roll Eyes

I have never had either in my hands but was told that the HM was the first to be made, the DT is a copy of it, and the Hall is a reinforced version of the DT.

So in a nutshell, the 32's are too small and therefore have little attraction to someone who is looking for a max effort performance induction system.

Of course this is all from my perspective which admittedly I am quite a bent individual to begin with, so you need to keep that in mind and take what I say with a grain of salt?
Last edited by panteradoug
The picture in this thread interested me. It appears that with the Cain manifold, the 48 IDF's sit under the engine screen with air cleaners. I love the look of Weber carbs but never really liked the idea of running without an air cleaner. If I argue that the air cleaners are a great idea, someone will report me to the moderator and I'm gonna get booted for arguing with someone.

Jack D. also posted about potential fire hazards if Weber carbs are used with air cleaners due to fuel reversion. I think you'd have to set up the engine for this by choosing or having a custom low-overlap cam made specifically for this.
Last edited by coreyprice
> Theoretically if a person restrains their right foot, the fuel mileage
> shouldn't be too bad.

Fuel economy can be better than a 4 barrel if properly calibrated. Vizard
reported 18 to 20 MPG on his SBC-powered shop truck with 48mm Webers.

> The 48's were really developed for Shelby's 289 Cobras. They start to show
> restriction issues at around 5,500 rpm's on a 289.

Vizard's testing on a 350 SBC found that 48mm Webers on a down draft IR
intake showed the Webers to be superior in peak power up to around 480 HP,
after which a larger 4 barrel carb on a plenum intake would make more peak
power but not necessarily better average. The independent runner manifolding
provides better power in low and mid-range so the cross-over point for
average power is higher.

Dan Jones
quote:
Originally posted by Daniel_Jones:
> Theoretically if a person restrains their right foot, the fuel mileage
> shouldn't be too bad.

Fuel economy can be better than a 4 barrel if properly calibrated. Vizard
reported 18 to 20 MPG on his SBC-powered shop truck with 48mm Webers.

> The 48's were really developed for Shelby's 289 Cobras. They start to show
> restriction issues at around 5,500 rpm's on a 289.

Vizard's testing on a 350 SBC found that 48mm Webers on a down draft IR
intake showed the Webers to be superior in peak power up to around 480 HP,
after which a larger 4 barrel carb on a plenum intake would make more peak
power but not necessarily better average. The independent runner manifolding
provides better power in low and mid-range so the cross-over point for
average power is higher.

Dan Jones


Can't argue with either. Best mileage I've seen with the Webers on my car is 15. Best with a 4179 Holley was 13-14. Of course it is very difficult not to put your foot into either.

I would say that the Webers on an IR (people have put them on single plenum manifolds) have a significantly better throttle response the a single Holley, at any rpm or speed. At least that is what I have experienced.

Over 100 mph, nothing pulls like Webers except a supercharger and possibly nitrous.

When you are driving the car, rather then having the engine on a dyno, I think the power with the Webers is much better over 100 mph then the Holley.

HOWEVER, I am usually trying hard just to hold on, trying not to blink as my eyes are watering from bouncing around, rather then sit there thinking, are the Holley and the Webers about the same?

Do you have a print out of that dyno run with the SB Chevy, Webers vs. Big Holley? I'd like to see that.

I have a feeling though that a nice set of two Holleys will yield the response of the Webers with the top end of the big Holley, and better overall drive-ability then either.

That certainly appears to be the case on my 347.

Don't forget that initially you are driving on just a 2v until about 3200rpms, and the secondaries are vacuum.

Lack of a manifold for the C of course is the killer to my theory for now though...just for now. Wink
quote:
Originally posted by Corey Price:
The picture in this thread interested me. It appears that with the Cain manifold, the 48 IDF's sit under the engine screen with air cleaners. I love the look of Weber carbs but never really liked the idea of running without an air cleaner.

Jack D. also posted about potential fire hazards if Weber carbs are used with air cleaners due to fuel reversion. I think you'd have to set up the engine for this by choosing or having a custom low-overlap cam made specifically for this.


In my experience the carbs don't even like having screens over them. The difference with and without is very noticible.

Also, I may be wrong again, but I haven't seen IDF's larger then 32's. Have you seen 48 IDF's?

If you look at some of the '60s muscle car tests, it was very common to pick up a few 10ths by taking off the air cleaner assembly.

To me it feels like you easily are picking up something like 80 to 100 hp in a 1/4 mile run.

All carbs like to run around naked.
I spoke with Jim Inglese about the concept, and he said it's possible. Jim said that he doesn't like the IDF's as much as the IDA's, but the IDF's are just fine. In fact, the IDF's are cheaper than the IDA's. Too bad the administrator likes these things as I think they're sexy.

Long story short, the IDF's would be fine and can be tuned very nicely. It's not EFI, but here's a guy who will taylor a setup to your engine for maybe still half the cost of the typical IR EFI setup done professionally.
Last edited by coreyprice
Can't really comment of the IDFs. No experience with them at all.
Considering though that the Australian manifolds are for iron 2v heads, I'd say there are no manifolds for the 4v's.
My thought is don't run 2v head stuff unless for some reason you have to.
Port flow on the newer "good" aluminum 4v heads is 330cfm ish. Do those Aussie 2v manifolds flow that? I doubt it? Look at the ports.
As it is Hall's manifolds for the 4v and SVO are the only two really available.
I heard Falconner & Dunn had built one, but one of them 10 years ago said, no, they never had.
I suppose if you can weld, you could make a sheet metal manifold for the IDFs on a 4v I suppose?
The IDAs really are streetable. There isn't much to be gained by running IDFs?
The IDA transition "issue" can be minimized by adding a third transition hole in the carb.
Still there, but almost gone.
The issue for me with Webers on the Pantera is you can't wssh the car unless you cap the velocity stacks. PITA. What do you do if it rains with them? Instant water injection?
Last edited by panteradoug
Great thread that gets me thinking about putting webers on the cleveland again. After doing a set of 48 IDA webers on a small block chevy and after personally tuning a brand new set (not as hard as you would think), me personally, I think I'd bite the bullet and let Jim Inglese do the setup (IDA's or IDF's)if I didn't want to jerk around with it for months and months. But then that is personal preference...if you want a project that consume lots of time there isn't one that is as much fun as putting on Webers.

Keep in mind that getting to the carbs will be a real pain in you back, literally! I did my first set on a mid engine race car where the entire back body section was removable. Everything was right there. On a Pantera....not so much, and you will be taking the carbs apart a lot...four times for every change. Possibly the easiest way to reach the carbs in a Pantera would be to remove the deck lid and laydown on the roof with you feet going toward the front of the car. I'm not joking. It got to be similar to adjusting solid lifters.

If you can get the initial setup for jetting from someone else that's got a set running well ON A CLEVELAND as a starting point (thank you Doug!), then why not save some money, but my guess is if the motor specs aren't identical you'll be making some changes.

I remember doing the IDA's with 44 chokes because many people told me 48's on a on a 360 inch chevy would be too much. There were guys running 427's with 48's. The heads I ran were the off road (as in track)competetion heads from chevy and the motor ran amazingly with 44's in a 11.5-1 compression motor with a mild cam (.520 lift cam). For street cars I remember hearing a lot about IDF's being a smoother transitioning carb from low to higher rpms. There is an additional mid range circuit in the IDF's as I recall and it makes street driving where your going gradually through an RPM range of 2500-3000 rpms smoother. An IDA setup from Inglese shouldn't have that issue. I was able to finally tune out that transition issue.

Haven't seen Jim Inglese's website before....but after poking around it gives me confidence he absolutely knows what he's doing. Make sure you get a GREAT linkage setup...spend extra on a good one. That was one of the issues of the IDA setup on the chevy...the IDA's seem to change ever so slightly, often. It's not that big a deal on a race car because you are usually not idling much, but if it's on a street car and drivablity a stop lights and lower rpm is important, it matters because once carb will get out of sync and throw lower rpm functions off.

Kid, I'm very jealous of your setup....would love to bolt that on to my motor!
Actually the issue with IDA's as would be run on the Hall manifold with linkage is almost eliminated as compared with what you would run on a 289 Cobra.
Some of the linkages tend to twist and get out of adjustment, not from street driving, but from running WOT flat out. When you want to come back to idle the car, that is when you will find out if your linkage is set up correctly.

Most people will build it where they over center it in order to get the car to idle as low as possible. That causes problems because the linkage will not stay there.

As far as getting someone else to do the calibration and forgetting about it from that point on, are you kidding?

The jetting changes from day to day as the weather does.

The air corrector you had in there yesterday at 50f and 20 humidity is now wrong for 95f and 90 humidity today.

Maybe southern California doesn't change like that but anywhere along the east coast of the US will. The changes are often drastic.

I don't know if he still does it but Jim used to send you one size up and one size down along with his dialed in setup.

The real issue with IDAs is that there is just no way that even an average car enthusiast is going to understand what these things are going to run like. You have to experience it for yourself.

I would say that the overall feeling is one of disappointment.

Apparently many people expect the carbs to make their 289 run like a 427? That just ain't going to happen BUT I will say this, driving a set of "well running" Webers is a life experience and regardless how you eventually wind up, i.e., with or without Webers, your life is never going to be the same again.

I think that speaks volumes?

Use Inglese's setup. Then you can bitch to him and not me, LOL! After all, he gets paid for it...I don't!

Best to everyone. Big Grin
Last edited by panteradoug
I did invest in an Innovate LM2 air/fuel ratio meter, which at the same time is a datalogger too, to get my initial set-up going.

As for the linkage, the connection in between the carbs is one thing, the throttle linkage is an other, as I found out, many people have the latter completely wrong. I brought this to JI's attention, and he changed his linkage design as per my recommandations. It is not only JI who had it wrong, I found similar mistakes at other vendors too.
quote:
Originally posted by Kid:
I did invest in an Innovate LM2 air/fuel ratio meter, which at the same time is a datalogger too, to get my initial set-up going.

As for the linkage, the connection in between the carbs is one thing, the throttle linkage is an other, as I found out, many people have the latter completely wrong. I brought this to JI's attention, and he changed his linkage design as per my recommandations. It is not only JI who had it wrong, I found similar mistakes at other vendors too.


The tower in the center is actually correct for the Pantera, since the pedal pulls the carbs.

Many Clevelands are in other cars such as Mustangs and for them the Pantera linkage is wrong.

The tower actually helps since there is nothing to bend in it.

This actually makes the Pantera simpler since you can hook the left side to the right from the rear of the manifold, left to right directly.

I find this helps a lot. I had this setup in my Shelby and the Mustangs need to be controlled from the drivers side of the carbs.

On that setup it is better to have the four carbs all in parallel rather then opposed. I had Inglese's reversing plates on that set up. One side is just a spacer, the other side reverses the carbs so that all four have the fuel inlets on the same side. This simplifies the linkage. For me on that car it was the only way to correct a geometry issue with the linkage. The Pantera with the pull on the bell on the tower doesn't have that problem. There the tower actually can get in the way.

The throttle body peopl use the Hall manifold but mill the tower out and put a vacuum box there with tower on top. Personally I think that is needless, but hey, what do I know about anything? Seems like not much?
Last edited by panteradoug
Yeah I will admit we in SoCal don't have to deal with as many weather changes unless we're going to an elevation location. Once they're set, summer, winter it usually doesn't change.

My linkage was set up with pedal stops at the bottom or WOT and with a giant flex cable that came in from the side...Don't think it could be much simpler in the center of the four carbs. No bell crank mechanism, just a bracket to hold the cable, yet would.

I notice all the current manifolds don't have a vacuum plenum...my manifold was a Mckay made from magnesium...it had about a three inch tall plenum.

Doug I would agree that once you have Webers, there is no substitute.
quote:
Originally posted by Tom@Seal Beach:
Yeah I will admit we in SoCal don't have to deal with as many weather changes unless we're going to an elevation location. Once they're set, summer, winter it usually doesn't change.

My linkage was set up with pedal stops at the bottom or WOT and with a giant flex cable that came in from the side...Don't think it could be much simpler in the center of the four carbs. No bell crank mechanism, just a bracket to hold the cable, yet would.

I notice all the current manifolds don't have a vacuum plenum...my manifold was a Mckay made from magnesium...it had about a three inch tall plenum.

Doug I would agree that once you have Webers, there is no substitute.


I'd like to see a picture of that manifold if you wouldn't mind posting one. Don't recall every seeing one. I have heard of it though.

My setup is out of the car and on the bench at the moment. Anyone want to see it, let me know I'll post a pic.
Some time back I was pulling together a group buy for the Cain manifold and we were getting a small discount for 5, but I struggled to find 5 people who were definitely on board. Since then exchange rates are worse and the manifold price higher.

One prior member of the group buy did tell me at the Fun Rally he was still interested, so if there are a couple more I could resurrect the contact.

The benefit is that 48 IDF's on a Cain manifold will fit under the engine screen and decklid with no cutting required. Also Mark at Aussie Speed confirmed there is enough material in the manifold to port to 4V heads.

I have set of 48IDf's on the shelf, just haven't gotten around to ordering the manifold yet.

Julian
IF you already have IDA's I personally see no point in going to IDFs.
The IDAs can in effect have in intermediate circuit created by adding another transfer slot hole to the carb.
In addition, if you are starting from scratch, electronic fuel injection would be the way to go.
The set up would cost about the same except for the addition of the CPU needed for the FI.
I suppose it all depends on how one conceives of the car as either an up to date ultra modern or a retro, period unit from the early 70s?
No matter which CARB system you choose, you still need to deal with the reversion in the carbs from the cam overlap. Not so on the FI.

Can someone explain what the mass is on the bottom of this manifold casting? To me it looks like an exhaust cross over plenum but there is none on this manifold.

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Doug said "The IDA transition "issue" can be minimized by adding a third transition hole in the carb."
__________________________________________
Doug please explain, I've never heard of that.

Also can anyone give their personal experiences on the IDF's on a Cleveland?

Is the Cain manifold a magnesium or aluminum? Looks like pickled mag...sort of like the McKay magnesium manifold I ran on the SBC. I personally wouldn't want a magnesium manifold on a street driven car. I had to drain the cooling system every time the car sat for more than a day because the magnesium corroded so quickly. A deal killer for a street car driven on a regular basis.

Also, will the IDF's WITH an air cleaner fit under the deck lid?
quote:
Originally posted by Tom@Seal Beach:
Doug said "The IDA transition "issue" can be minimized by adding a third transition hole in the carb."
__________________________________________
Doug please explain, I've never heard of that.

Also can anyone give their personal experiences on the IDF's on a Cleveland?

Is the Cain manifold a magnesium or aluminum? Looks like pickled mag...sort of like the McKay magnesium manifold I ran on the SBC. I personally wouldn't want a magnesium manifold on a street driven car. I had to drain the cooling system every time the car sat for more than a day because the magnesium corroded so quickly. A deal killer for a street car driven on a regular basis.

Also, will the IDF's WITH an air cleaner fit under the deck lid?


The IDF is being touted as a street carb vs the IDA, a racing carb.

If you catch the comments about the IDF, "it has a mid-range circuit".

One of the idiosyncrasies of the IDA is that on an IR manifold on a V8, there is an rpm range, observed on most cars to be about a 400rpm spot, between 2,500 rpms and 3,200 rpms where the engine becomes unresponsive to throttle input, i.e., a flat spot.

I do not know if the transition flat spot exists if the carb is used on a common plenum manifold. It may be a IR manifold issue. Don't know.

This is caused by the design of the carb itself.
It has a hole in the throttle bore, below the throttle butterfly through which the idle adjustment screw projects. It has another just above the throttle plate at idle position.

This is usually called the idle transfer slot in other carbs like the Holley. On the IDA, it isn't a slot, it's these two holes.

Now, cut me some slack on this because I am doing this from memory, ok?

I believe there are two holes in there. The access to them is through the slotted brass screw under the idle adjustment screw.

I believe there are two holes, one like I said for the idle screw needle, another above it maybe at 3/16" higher, above the throttle plate and at the notch in the plate.

That distance between the two is the significant part to this transition between idle/part throttle and main fuel system.

That distance also coincides with the "transition flat spot" of the mentioned rpm spread above.

In attempting to eliminate or reduce the flat spot, some "tuners" have added a third hole, in between those two existing.

This lets the idle circuit continue to a higher rpm range overlapping the main circuit kick in.

Now I personally think that because these are hole and not slots (like in a Holley) you can not entirely eliminate the flat spot with it, but you certainly can reduce it.

I do not have this modification on my carbs. Some days my flat spot is there, some days it isn't. That does have to do with a lot of things including the size of the chokes, and most importantly, the WEATHER. Clean, dry low humidity air accentuates the flat spot. More humidity tranquilizes it some.

IDA's change with the weather, like it or not.

The bigger the chokes, the more consistent the flat spot seems to be there...seemingly.

This is probably one of the modifications Inglese will do on a carb that he knows will be used on the street. An IDA that is. The IDF doesn't need it.

As far as the IDF's being shorter, along with the manifold, I will say this, the IR systems are sensitive to ram tuning length. The longer the better.

Have you ever seen the long ram tubes on the IDA's? What do you think they are there for?
The longer they are, the more torque they add, and it is noticeable.

Like I said, I haven't worked with the IDF's, but the entire ram length to the valve is noticeably shorter then the IDA.

I'd bet you a nickle that adds to loss of drive ability of the IDF's? Again, IR carb systems are VERY, VERY SENSITIVE to induction length.

You may be attempting to reinvent the wheel with the IDF's?

Nothing naturally aspirated (carbs)seem to run with IDA's flat out. Maybe the IDF's come close, I don't know?

That's my explanation Tom. Best I can do. Hope it makes sense to you and helps?
Last edited by panteradoug
i tryed IDA48's on a track-Porsche 928 for the fun... all custom build , all for nothing... jetting became a nightmare Eeker quit the idea , perhaps ever again when i have tooo much time Big Grin

no, besides the looks , i wouldn't try it again , sure not on a sub-"daily" Pantera ! i even wonder , IF you can get it right, what difference you CAN feel in a street driven car....???? perhaps at WOT ... 2% a year ? giving up some torque , using the other 98 % of the year ?
but yeah, i DO love the looks ... Cool
quote:
Originally posted by Kid:
There is a short movie of that 928 on Youtube, correct?

I bought a 40 year old car, partly because of the looks, and don't mind the old thing has some "issues", so why not IDA's Big Grin


I actually feel the same way. I feel the modifications should be period correct and I actually use the Gp4's as a target/role model. Wink

Actually on the tuning, Webers being "off tune" is actually a misnomer or an axie moron. If the are off, the car won't move out of the driveway.

What the issue is, is maximizing them for that day, just like you were racing. What ever the setting turns out to be, is the best the car will run on that day, and you leave it alone.

My setting is 140f/160a, F5 mains. .67f idle on the stock 110 idle air holder. The chokes are 40.5mm, which were custom milled down out of 3/16" thick wall aluminum tubing.

I will tell you that it will also run better on 170f/190a, and F7's seem to run as well as the f5's. The car will pull very, very, very hard on that setting and I actually like the color of the plugs better with it then the 140f combination.

Idle set screws are about 5/8ths of a turn out from the seat.

When the transition flat spot is there it is at 2800 to just under 3000 rpm.

I haven't got the courage to try the third hole yet. The problem is if it screws up the carbs, you have to solder the hole back up.

The IDA's have gotten a little pricey to screw around with them.

Here it is. You can see the third hole clearly in this picture. There are those that swear by it.

Here's a discussion about it from Club
Cobra.
http://www.clubcobra.com/forum...ransition-ports.html

This is the article the picture below is from.

http://www.aircooled.net/rebui...-ida-vw-carburetors/

The new third hole is the top one. The article states that the "newer" IDAs come with the three holes.

Anyone here have maybe the made in Spain 48IDAs of which they can check on?

Some have questioned if the third hole makes the idle heavier.

Apparently no, and because the venturi effect only draws fuel out of one hole at a time as it aligns with the throttle plate. The throttle plate moves in relationship to each hole as you operate the throttle.

It makes a lot of sense to add the third higher hole since it is "higher" in the rpm cycle that the idle circuit stops functioning and the dead spot occurs.

To make it operate at a higher rpm, it needs a higher transition hole. Seems ridiculously simple, but carbs are not rocket science.

This "tune ability" or flexibility is why many say the IDA is the carb to run even on the street.

It isn't just the V8s that see this transition issue. Virtually every engine the IDAs are used on exhibits the transition issue.

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Last edited by panteradoug
I bought a set of Webers long time ago for mine. They were purple which wasn't going to do. I have been tearing them down and rebuilding them which is good. I don't believe they have ever been used but they needed cleaned up. hings like bearings not moving well, dry gaskets, etc.

I drilled the 3rd hole and tapped it for a plug. I have been sandblasting and powder coating the carbs.

The Hall intake for the 400 needed spacers which I was not going to do. I started building my own intake but time got the better of me. I cut the Hall intake in half instead.

I did find the Hall intake put the carbs a little too close together. Linkage had to be slightly bent not to bind and the fuel rail barely went on with a little pushing.

I'll be laser cutting a plate to go in between for linkage.

What fuel pump do you guys prefer? Do you have a minimum size fuel line?

I am going to put in an O2 but the best spot or me is right against the head. I need to see if the O2 can be that close; I am not sure it can.













I like it. Nice solution. My Doug Nash intake was just like that with a plate underneath.

I don't find issue with the linkage on the Pantera. I did run that set up on my 68 Shelby when I had the Boss351 in it and I did have linkage issues there.

The simplest solution on it was to the linkage was to use Inglese's adapter kit to have the carbs parallel rather then opposed. The throttle input also had to be put on the drivers side of the manifold and the pedestal was useless.

theoretically the Hall manifold is correct with carb orientation because of line of sight to the valve. Does it really matter? Probably not much.

For the Pantera, the pedestal works perfectly for me.

I had binding initially with it on the Pantera but moved the left to right bank connection to the rear. That made a very simple linkage connection at all points.

So what's wrong with purple? Big Grin

I use a Holley electric fuel pump and find -6 hose are fine. 3 psi max. You do not need high pressure with these things. That is Holley think.

I don't use those fuel rails. Those are the ones made by ISP in Colorado. I use 3/8 ss tubing with tubing nuts and the Earls Weber T fittings. I like the sorta retro/techo look and they make great handles for hauling the manifold around.

How much off center are the fuel holes on the rails? 30 thousands? Gotta leave the carbs loose, align the rails, then tighten the carbs I would think...not like you wouldn't already know that?

Check out Jay Cee web page for the Weber parts you need.

http://www.jayceevw.com

The bearings are sealed. There should be no way the throttles should bind. White lithium grease here and there is all that you need.

The real question to me at the moment with Webers is the camshaft.

You need to remember that these things were run with race duration cams and overlap that blew the fuel out like a geiser.

I can tell you that my heads need lift to work. The "Weber" cam with 586 lift and hydraulic lifters isn't going to cut it for my heads. Try 6 something.

That is the part that is unresolved for me.

I still feel that using the Weber cams gives away 100hp needlessly. This is the part of the race vs. street that I may never be able to resolve?
I am afraid I did not consider the webers when I built the engine. I figure at this point it is what it is. The engine was built as a low rpm torquer engine. My goal was very good tq limiting rpm to 5500rm. By doing so I figured I can get by with much less valve spring problems. We dynoed it with a Deamon on a CHI intake right at 500hp with 534lbs tq. The engine had 434lbs of tq at 2000rpm and the dyno could not start any lower with he tq. I can also tell you the exhaust primaries on the dyno were pretty small.



Cam is crane 529721
276/284 seat to seat
214/222 .050
.562/.586 lift
111 center

If I ever get caught up I have another 400 I want to go hog wild on. We have a draq strip a couple miles from my house. I have an old nascar I want to use as a rolling dyno and would like to play use that to set up another motor. We'll see if it happens. Life is pretty damn busy right now.
How close do you think I can mount the O2 to the head? I have completely different type of headers with all 4 primaries going to the back. The primaries land in a common muffler far down the line.

I am afraid if I put it in the muffler section it will be too far away and not heat up adequately. Since they need to be mounted at least partially upward, this limits my location to the top of the runners here. My concern is that the O2 sensor does not get too hot:








In the headers I made for the MG I run them about a foot off the head. You can see the port on the right side of the right header here:


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