Recently, we had the pleasure of doing the final sorting of a very special Alfa-Romeo—a 1961 Sprint Zagato (SZ-1) of which only 149 were made! The body is all aluminum and all the windows but the front windshield is Plexiglas.

When we first saw the Alfa, a beautiful restoration had been done in California. We were charged with the following request; check it over for the Colorado Grande (1,000 mile rally through the mountains of Colorado). We were asked to make it stand up to the task. We adjusted the brakes, changed the engine oil and filter, checked all of the fluids, set the tire pressures, repaired a sticky throttle, installed heat range hotter spark plugs, adjusted the timing and idled fuel mixture for our altitude and adjusted the throttle linage for full throttle. We detected a very weak charging system (o.e. marelli) and we decided to deal with that after the Grande was over.

Off it went to the Colorado Grande and B. C. reported it performed flawlessly.

When it returned, we checked the cam timing and valve adjustment. We reset the cam timing after locating the proper specs from Megacycle (who welded and reground the cams to take advantage of modern technology). We adjusted the valves which requires removing the camshafts and followers, measuring the shims on the end of the valve stem and replacing them with shims of the proper (calculated) size, reassembling and rechecking the clearance and if you are holding your tongue just right the clearance will be correct, if not you do it again! Next, we adjusted the timing chain. Alfas upper timing chain has a manual adjuster which is a regularly scheduled maintenance item. While completing the cylinder head maintenance, we retorqued the cylinder head.

We removed the tachomemter and speedometer and sent them out to be rebuilt. We got a call from Margret at Moma who said, “I’m glad you guys sent them in before they grenade. Most people wait until it’s too late and for parts for these (jaeger or Veglia) gauges are few and far between.

We installed threaded insets for both door check straps retaining screws that had previously had 3 oversize sheet metal screws installed. A permanent and proper fix.

On to the charging system. The original Marrelli generator was marginal at best when it was new. Almost 50 years later it’s dependability is just not there. The gentleman who used to rebuild our generators and regulators passed away over 10 years ago. We looked high and low to find an alternator that would fit in the confines between the timing cover and steering box. We checked everywhere ever the Kyboda Tractor Dealer and a Harley Davidson repair shop. The Harley generator looked promising, it was really well made (ball bearing, beautiful case) and the mounting ears bolted right up to the Alfa front cover! I called the engineer who designed the replacement generator for the Harley’s and he said the output is thermally limited to an optimum operating temperature of 72 degrees and case is not vented. It is not. Designed to operate in an engine compartment it is supposed to live in the airstream in the front of the Harley.

Next, my friend Jonathan suggested a Geo Metro/Suzuki alternator. We obtained a Bosch remanufactured one and tried it, again the mounting ears fit but the space confines are so tight that we needed to grind the case and we fabricated an adjusting bar bracket. After our first test fit we found there was no room for adjustment. We solved that problem by making a “split” pulley just like air cooled VW and Porches used to provide belt adjustment. While testing the charging system, we noticed steam from the engine compartment, which we noticed was coming from the heater valve. We obtained and installed a new one— wow an easy bolt on/bolt off repair!

We fiddled around with the weber jetting and found it had 32mm choke tubes—huge for a 1600cc engine at this altitude. With a combination of idle jet changes we were able to make it start easily, run properly cold as well as warm, and loose the flat spot at 3500 RPM (which I attributed to incorrect CAM timing).

Next, B.C. decided to go with our recommendation to install electronic ignition. We did that set up for 14 degrees btdc at idle and 44 degrees at 5000 RPM.

Wow it starts and runs almost like a modern car! B.C. then pointed out that the rear end makes a huge “popping” noise on hard left and right turns under power. He was told “they are all like that”—my response was let me try some limited slip fluid additive. Amazing—with the correct additive in the differential fluid, the noise was gone.

Rob performed a precise 4 wheel alignment and the difference it made in the way the Alfa drives was nothing less than amazing.

Lastly, for this visit I tried to check the pressures and really had to struggle to do it. The wheels on the Alfa had aluminum centers riveted to steel rims. It had tubes with solid valve stems that were jammed against the rim. The solution that Frank came up with was to have new valve stem centering collars made that fit properly so the valve stem was not jammed against the rim.

On to our current project. We are working on removing a really annoying buzz from the throttle linkage. Again, B.C. was told, “they all do that.” We are also installing 30mm choke tubes for totally “lag free” throttle response. We ended up removing the carburetors (trying to remove just the airbox would have required an act of congress) we discovered a worn out throttle bellcrank and missing return spring.

Now to try and locate one. After exhausting all my sources for an original return spring (I even had the part number from the original parts book), we ended up getting a spring from our local Ace hardware store. After installing the spring & removing the extraneous one that had been previously installed, the throttle linkage with it’s new bronze bushing for the bell crank worked flawlessly. Since B.C. had charged us with not drilling any holes in the car we glued a throttle linkage stop to the firewall. No more buzz!

After installing the 30mm choke tubes we had to replace the idle jets again. Finally we had a 50 year old car that starts & drives almost like a modern car. No more clunks, no more waiting 20 minutes to drive off after a cold start & no more buzzing from the throttle linkage! With the installation of an alternator in place of a generator everything electrical works better especially at idle. The ignition system makes a more consistent spark as it has a constant voltage supply. The headlamps are brighter, everything electrical is just happier!

What a treat to be able to finish the piece of automotive history!

Mark Weiner
Concours Cars
2414 West Cucharras Street
Colorado Springs, Colorado 80904
Phone: 719 473 6288
Fax: 719 473 9206
www.concourscars.com