Origin7

@IamScotticus fingers crossed. I'd rather be than wrenching at the moment.

That sounds quite manageable, and much easier than taking the head off. Looks like I'll be going after this as soon as the seals come in from Burton. Hopefully, they are the right ones

Has anyone replaced the valve seals with the head on? Trying to gain a better understanding of what's involved.

@IamScotticus All good points. Thank you for the feedback. I am with you 100% on the catch can. I've got one on the way. Also, I may eliminate the heater/hoses. I'd like to use that space for other things.

I am new to this, so feel free to critique my approach or tell me if anything here seems incorrect. I tried increasing the advance at idle, but the engine didn't seem to like it. It showed the obvious signs of too much advance. Long story short, I went back to the timing curve shown above. It's also worth noting that I confirmed with a timing gun that the timing value and RPM at idle matched what the engine was actually doing. This was just to confirm that the 123 system was set up properly. With a reasonable baseline timing curve, I then jumped into the carbs. The shop set me up with 28mm chokes, 55f8 idle jets, f16 emission tubes, and 120 main jets. Idle mixture screws were set 2.5 turns out. The emulsion tubes and mains jets matched what @JohnCh kindly sent me for the factory setup. The shop insisted 28mm chokes and larger jets were a better setup than the Caterham factory setup . The plug color and the way the car was running indicated this was not the case (way too rich). So, I installed 32mm chokes and 45f9 idle jets. I also changed out the idle mixture screws, which showed some signs of overtightening or corrosion (maybe both) on the needle portion. I backed out the idle mixture screws 1.5 turns and fired it up. I adjusted the idle mixture screws per the procedure. Next, I adjusted the idle speed, then synchronized. Long story short, the engine is running much better. It idles more smoothly, no spitting back through the carbs, little to no smoke, and pulls through the mid RPM range really well. I have to say, setting the idle mixture screws is a bit difficult. I think I need to work on this more. I do get some hesitation/bogging when I am driving and crack the throttle from low rpm. It's not terrible, but I hope to eliminate this. My understanding is that this could be caused by being either too rich or too lean with the idle screws. I like @NSXguy's recommendation to add a wide-band O2 sensor. For someone just starting out tuning carbs, I think it would be nice to see the result of the changes I am making. This may be the next step for me. Anyway, I'd welcome anyone's feedback, especially on getting the idle mixture screws set well. I am definitely in the ballpark, but shooting for perfection .

I'm working on establishing a good, safe baseline ignition curve before I start working on the carb setup. I am getting a lot of smoke after idling for a bit, so it seems like it needs to be advanced at idle. Hoping to do a quick sanity check here. Here is my current setup: This is what I am considering - Fewer plotted points, adding advance at idle, and all in at 3k. Look about right as a starting point? RPM Advance 500 12° 1000 16° 1500 22° 2200 28° 3000 32° 4000 32°

I’m looking for a roll bar for an ’89 Super Sprint (imperial, De Dion). Ideally something in the New England area so I can pick it up and avoid shipping. I’m after something taller and more substantial than what I currently have. Preferably, a bar that’s better suited for track days. It doesn’t need to be a perfect bolt in. As long as the geometry is close, I can handle any modifications needed to make it work. If you have anything that might fit the bill, please let me know. For reference, here’s what I’m currently running. It doesn’t exactly inspire confidence.

This is a valid point.

Thanks! That's a great idea. Much easier than remodeling it in various sizes.

I needed a plug for the port in the firewall that allows you to access the speedo cable connection. I designed this with a flange in the back to keep out moisture. When printed out of flexible TPU, it pops right in. File attached. Feel free to use, share, and modify. Speedo_Plug_Rev1.STEP

Thanks @CBuff. Great feedback. I like the idea of the bedliner under the seats. Seems like the perfect solution. I just carpeted under my seats (because that's what was originally there). That probably makes me even more of a polishing queen.

Thanks @Croc. These are pricey, directly from Caterham. For the price the CBS offers, it makes a lot more sense for me to replace all of mine. After 37 years, I'm probably due.

Does anyone know if these rockers have improved over the years? I am thinking about replacing mine from an '89, but I am not thrilled with the "action" or weatherablity of the older ones. Curious to know if the newer ones are the same.

Great idea! That's much closer to what I'd like to spend too. Thanks!

Carpet on dash? Is that actually something people do?