Weber Carb advice.....

I know nothing about the particulars of weber jetting, though I agree that the size is a bit large for a street 1500.

I'll go all the way back to your original post, because I think the answer is there:

When I purchased the 45 DCOE's they came with 36mm chokes and jetted accordingly. The car ran great with the power really coming on around 4500 rpms and pulling like a train to redline.

I installed smaller chokes to lower the power range to a more streetable application but now it pulls hard off the line but sounds like it's sputtering at the 5000rpm range and won't climb any further.
Click to expand...

Ok, so now to eliminate other variables put the chokes and jetting that worked previously back in and see what happens.

Also, go to a dyno, preferably someone who knows carburetors, and bring a bunch of jets / chokes to play with.

Around here I can get a couple hours of dyno time for less than $100

This is something that is hard to diagnose and tune seat of the pants, but very easy to diagnose on a dyno with a wideband AF meter.
 
The pictures of that plug look way lean to me

At least in some part of the range - the tip looks as though it has been very seriously hot! I have no first-hand experience with these carbs on this car but, if it were mine, I would quickly change the main jets to see if it seemed I was going the right way. Go to larger mains - say 135 - and let us know what happens.

I also bet (based on my experience with my 40s) that the F8-55 idles are too much and should be dialed back to around F8-45. Because of the overlap in the idle and main circuits, larger idle jets will help your lean main condition to an extent but isn't really the way to address your problem.

Did you ever get around to checking the cam timing? For now you can just verify that the marks are aligned correctly.
 
I do agree, that photo is with 125 mains and 210 air correctors and F8 50 idle jets.

I've since changed the jetting to 130 mains and 200 air correctors which will richen throughout the entire rpm range and I've gone back to F8 55 idle jets as it idles much better this way. I haven't had a chance to drive it yet with the changes but will take a picture of the plugs and report back with the A/F gauge readings. No I haven't purchased an advanced timing light yet but I have confirmed that the marks are aligned correctly.

Thanks,
'PeteX1/9
 
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" I've since changed the jetting to 130 mains and 200 air correctors which will richen throughout the entire rpm range and I've gone back to F8 55 idle jets as it idles much better this way. I haven't had a chance to drive it yet with the changes but will take a picture of the plugs and report back with the A/F gauge readings. No I haven't purchased an advanced timing light yet but I have confirmed that the marks are aligned correctly. "

So I took her out for a nice drive after the jetting changes were made yesterday and I was very pleased with the results. It idles at about 12.9 which is richer then before but at WOT which pulled awesomely to 6000 rpms and then I let off the readings never went beyond 13.8 so I'm very happy about that. I do have to buy an advanced timing light so that I can dial it in properly. I took a couple of photos of the spark plug pulled out once I returned and it looks picture perfect accordingy to my Haynes manual, not to rich and not to lean.

Before jetting changes (too lean)





After jetting changes:



'PeteX1/9
 
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That looks close..

I still think I might try that F845, if you have one in your kit. I'm guessing that the black areas on the electrode are from idling in after running pretty good on the mains. That said, it ain't bad and you sound happy so you could just leave it alone - but where's the fun in that? Congrats!
 
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