Rostra Cruise Control - running off the HEI distributor Tach signal

[Kelvin]

This is a great post! I am replacing my OEM cruise with a Rostra once I switch out the steering column. The existing OEM Cruise is missing parts anyway and likely leaking vacuum.

I believe there is a post on this Forum about correcting the +- 2 mph creep - it’s a dip switch setting on Rostra. If I find those instructions in my notes, I will share here.

Ed

UPDATE: You may have already seen this dip switch setting but it has to do with 1 mph drop kwhen setting cruise.

View attachment 11526

Make sure the slack in the cruise control cable is minimal. It's a chain at the throttle bracket, so maybe you can take out one "ball" in that chain. I use Rostra in the GMC and my Datsun towd. I removed the slack, and they both worked better.

 

[pilondav]

On the Rostra website I only see the GlobalCruise model. I don't see a WorldCruise and it doesn't come up in a Google search. Is that the name JimK has given the kit he sells?

I confused the GlobalCruise with the WorldCruise model. My mistake. I believe the WorldCruise is obsolete and given that, I assume Jim is going to ship the GlobalCruise model.

At first I was wondering how Todd set his controller to 10k PPM when the attached DIP switch documentation (which appears to apply to the WorldCruise model) only went up to 8k PPM. Then I pulled up the GlobalCruise manual and found Rostra added two more DIP switches for more PPM options.

I think I'm going to follow the tried-and-true method with the speedo transducer instead of the tach-as-VSS method after all. I thought about the downshift issue as well, but I couldn't figure out how the controller could prevent rapid deceleration. Apparently it doesn't. Even with the torque converter slip, I don't think it's possible to avoid that deceleration.

 

[pilondav]

I'm looking over Duane Simmons' (RIP) installation notes for the UltraCruise II controller. He says to ground out the tach input signal instead of connecting it to the distributor.

What's the current recommendation on this for the GlobalCruise controller? I like the idea of having some engine overspeed protection, but I think I can tell by ear if it's really overspeed.