Should I upgrade carb?

[Nanonevol]

Often hear of people putting on a new air filter, or some additive in their gas and claiming some wonderful performance increase, so I'm a bit skeptical of claims. How about the upgrade from a 32adf to a 34adf? My stock '77 is fun to drive but a bit scary in traffic or on the highway because it's just not that quick or fast. I realize these are sports cars but they are not race cars in stock form. The best feature is the top down. It's really just a weekend toy mostly and I don't have a lot to invest. If it won't make a significant change I'd be happy enough to leave it as it is and try to stay away from our extremely hurried Massachusetts drivers.

[djape1977]

go for 34
well worth the effort

[Warren]

34ADF is a significant improvement.

[Nanonevol]

Cool, thanks. New carb and some fuzzy dice (not seriously) and I should be able to keep up.

[vandor]

You should also consider upgrading to an earlier four into two exhaust manifold with the appropriate downpipe. That and the carb should make a big difference.

[Nanonevol]

Yeah, thanks, I did that. Well, I put in a 4-2-1 but I don't know that it's an early one, in fact I'm pretty sure it's not. I got a downpipe that routed my exhaust down the passenger side of the car rather than the middle and used a 3 bolt cat delete pipe. ANSI muffler was fine. Got everything quite cheaply on ebay. At the time I made some posts and got some replies where I compared the openings on my 4-2-1 and it seemed mine were not as wide as some others. Haven't been able to find the definitive answer on this but a comparison with my original manifold proved it was an improvement.

[carl]

Your 77 spider came with a dual point distributor with the ignition timing set at zero degrees before top dead center. Switch to a single set of points and set the timing at 10 degrees before top dead center. Also, the throttle linkage on the intake cam box has two return springs, a hairpin and a coil spring. Remove one of them. I find the spider return spring set up so strong that you really have to lean on the throttle pedal to get full motion on the carb. A lighter return spring makes the car feel peppier because you are opening the throttle up further and faster. Also, make sure you are revving the motor. When I had my Miata I got a book on Miata performance and the first mod was to rev the motor over 4,000 to double the horsepower! Most folks drove their Miatas under 4,000 rpm and were missing half the horsepower which was found about that rpm. I don't think the spiders are that bad but if you drive it like an old lady you are missing some factory power.

carl

[Nanonevol]

Thank you Carl, I appreciate the feedback. Actually, the PO put in electronic ignition of some sort. I don't know much about that, just that I don't have to set points, etc. I will definitely look at the linkage springs. Haven't actually started the car yet this year but I do want to drive it a bit more as-is to see what I have. I get the part about revving the motor up. I need some practice I suppose. I do love the sound of the motor. Especially when I'm downshifting and going into a curve - it makes this "ring a ding ding ding" sound that is great!
~Nick

[Nanonevol]

This YouTube video of an Abarth Spider has great sound and the driver is really revving it up.
https://www.youtube.com/watch?v=C2M3JRQefOM