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I 2006 I decided to start modifying the engine.  When I first did my restoration I thought I would keep the engine looking completely stock.  After driving it that way for a couple years I wanted more performance but still wanted to stick to "vintage" performance improvements.  I thought about EFI, and several friends told me I should go that way, but I decided against it.  I decided to install a set of Weber DCOE 40 carbs.

I got the carbs from Ebay.  They needed rebuilding but were otherwise in good shape.  The manifolds are from Cannon.  Several people suggested that I go with a traditional cross bar linkage and not try to use the center-coupled linkage that is so popular in today's carb kits.  The cross bar setup allows for multiple adjustments to each carb's throttle lever.  I learned that the throttle linkage needs to be very solid and precise to get the carbs to stay in sync.  Small adjustments of just a few hundredths of an inch on the linkage made a big difference.  I went with a single common air filter to avoid carb balance problems that can be caused by slightly different air flow from multiple "sock" filters.

I originally went with a Carter fuel pump but did not like the noise it made.  It also ran at too high a pressure for the Weber carbs.  Most "carb" fuel pumps are set up for American carbs that like 4-6 PSI fuel pressure.  Webers like about 3 PSI and no more.  The higher pressure from the Carter pump was causing problems with float levels.  Since I would need a fuel pressure regulator anyways, I decided to re-install the OEM Kjet pump (75 PSI) and get a good quality bypass style regulator that would provide the 3 PSI I needed.  This solution appeared to work very well.  I do need to make sure that the return line is very solid as a blocked return line could cause very high pressure to the carbs which would flood and cause a possible fire hazard.

I taught myself to tune the carbs, I purchased several books on the topic and was able to buy jets off of Ebay for a reasonable cost.  After about 3-4 months of trial and error and several hundred dollars worth of jets later, I had the carbs running pretty well.  They were not perfect, I had a stumble off-idle if I opened the throttles too fast.  I needed to wait until I got the RPMs above about 2000 before I could stomp on it.  After 2000 RPM, the carbs responded great.

I drove the car with the carbs for a full year.  I made a 700+ mile trip from Rochester New York to Greensboro North Carolina for Octoberfest without any problems.  The car got about 24 MPG on that trip.  I kept trying to fix the off-idle problem but I could never get the carbs "perfect".  I almost got into an accident on two separate occasions when I was too fast on the gas trying to jump out into traffic and the engine almost stalled.  I ultimately decided that my friends had been right all along and I should go to EFI for the type of performance and driveability I was looking for.