redursidae

Thank you, Austin. That’s good info! Unfortunately the bead roller was not the right size and didn’t work. In the end I did not put a bead on the pipe and only used a fuel safe rubber cap and a clamp per the picture. Anyways, here is the link: https://www.pegasusautoracing.com/productdetails.asp?RecID=31584

@Austin David Regarding 5w50, is not so much difficulty finding it, as it is how long it may take to warmup in the colder months here. I’ll order some to try it out anyways, and could go back to 5w30 or 5w40 in the winter. I also wasn’t sure if the 5w50 would make the VVT unhappy, but I have been told it would be fine. @Austin David Any chance you could measure the clearance of your pan to the ground? You also have a Duratec which I have to imagine has a different height. Having rocks, branches and potholes on the road is common here. Bridge junctions in New Mexico are also horrible, and I already scrape on those if I’m not careful. Josh Robbins said I could raise the front further, so maybe I’m overthinking how the geometry may get affected by that. It’ll probably be better anyways because of the drastic unsprung mass difference. And since I do have an affliction, a dry sump is possibly happening at some point in the future. Yes to all of those adjustments, and good point about the rake. The ride height dropped an inch in the front going to 13s. The rear dropped about 1/4 to 1/2 inch. I took measurements after your comment and it will need readjustment for the 13s, as it had too much rake. I didn’t jot down the numbers, but it was around an inch higher rake than the 15s. I’ll take close measurements once I’m able to get my own set, since these are only for test fitting and I don’t want to mess with the current setup.

If Road America’s carousel is the bar, then I’ll be fine. I don’t plan on taking the Cat to a big track like that. One of the local Caterham peers lent me his spare set of Apollos to test fit and measure clearances. It’s scary. 2.5” of ground clearance at the lowest point of the oil pan with Apollos and well worn Avon ZZRs. I may still get a set, but it may only be a track setup as it will certainly hit things around here. As far as fitment, the rear section of the exhaust is in the way. I’ve been wanting a side exit anyways, so this is a good excuse: I also re-weighted the car on this setup since I had added the lights and passenger seat. This is with 1/4 tank of fuel and 13s. The front 185/55/13 Avon ZZRs on Apollos are 22.6lbs, and the rear 215/55/13 are 27.6lbs. The 15” Caterham wheels with Toyo R888R 195/50/15 weigh 31.2lbs each. Huge difference, but is it worth risking an oil pan for it…

No oil cooler on mine. Alright, same setup as this one. I’ll think about it. What’s considered a long right in this context? It should be fine in my local track and at Grand Junction, as those are like a big autocross. My concern is Pueblo Motorsports Park and La Junta. Those have longer corners.

Yes I did mean Celsius. Roughly 96-98 Fahrenheit at the track yesterday. Good to have confirmation on this, thanks. I'll run a 5w-40 first, and then a 50 if the pressure still drops too low. Were your Zetecs dry-sump or wet-sump? Man that's kind of a bummer, as I was planning to do a couple of trackdays this year with the local group of Caterhams. Well, only one of the near tracks has long corners, while the others are more like a big autocross with straights. Think it'll be fine for the latter? At any rate, my Miata will continue to be the dedicated trackcar, and the Cat is more of the 4-wheel motorcycle for me. The thermostat is either 90 or 95C, but I don't know for certain. I think the thermostat is working because on the street and for those first 4 sessions it stayed right at 90C, which is near the thermostat temperature. The fan is on a thermoswitch that runs at 90C, and shuts off at 84C. Those may not be the exact numbers but is close. I saw it printed on the switch when I did the radiator but failed to take a photo. But the fan does work, and it starts near the 80C mark on the gauge (which is why I know it reads low), and it was running the whole time at autocross. One thought I had was that there is no baffling between the radiator and the bodywork, so a lot of the air is going around it, and the fan may not be doing much. The new radiator also pushed the fan away compared to the original, which I have to imagine also reduces the efficiency of pulling air through it without baffling. But yes, I'll investigate further, and use the OBD scanner next time to check the real readings too.

No oil temp gauge at the moment, but I have the parts to install a switch and make the coolant temp gauge read oil temp too. Just haven’t gotten to that yet. I have AMSOIL 5w-30 in it now, since that’s the weight the manual called for. I see Caterham recommends a 5w-50 for their Motorsports engines, even the 485, and that’s why I’m leaning towards trying that. Yes it is odd. It even happens after a spirited drive in the mountains, although not as low as I saw this weekend. Sure seems temp related, but I suppose it could also be the sender or gauge reading low somehow. It wasn’t worth the gamble to me this weekend though

Yesterday was the autocross, and the new alignment (and more confidence) did wonders to the handling. The car was happy to oversteer at will, and was heaps of fun! The engine is so fun to rev out. Unfortunately I had a couple of issues in the hot day. The weather was 36C and after 4 runs the engine was on its way to over-heating territory. I shut it off with the gauge indicating 100C, but it reads about 7C low, so it was really about 107C. The most concerning part was the oil pressure dropping near 0.6 or 0.7bar at idle unless I held the throttle open a bit. However, I called it quits once I saw it struggle to build over 2.5bar at 3k RPM. All returned to normal after the engine cooled down again in the afternoon, but only did 3 more runs before oil pressure started to dip at idle again. At any rate, it was an awesome day. Fun time with friends, and feeling great about the car overall. I could do more changes to the alignment but I'm happy enough at this stage. I imagine 13" wheels will change it a little too, so maybe I'll wait until then. I'm going to look into using a heavier weight oil to see if it helps the hot pressures. It seems the stock Focus SVT has an oil cooler, so I wonder if the oil tends to get toasty on these with 5w-30?

Sun hoodies are awesome.

The Spectra L066 did the trick! No more smell and no more fuel seepage. I’ve run out of time to work on the car and adjust the caster before Autocross but that’s ok. Don’t know about 150, but luckily my cutoff is much higher! Fun fact, my SVT and my friend’s 485 are the same weight. We don’t know the reason as we expected the iron block to be heavier. Maybe the diff+trans?

Returning from Cars and Coffee on a stormy afternoon.

Thank you for all this information Croc. It's very helpful and gives lots of food for thought. I'm going to increase the caster angle by a couple of shims (it's at the minimum now) before the next autocross and see how that feels before I change much more. I'm enjoying the current settings on the road, and have been experimenting with the balance. Having a passenger really changes things for obvious weight distribution reasons, but riding solo the rotation is there. I'm about to hit 1k miles since purchase, mostly backroad miles and many smiles. I'm still dealing with a strong fuel smell out of the tank when it's over half, and seeing wet spots around the fuel level sender. The culprit appears to be the fuel level sender gasket, so I ordered the Spectra L066 part I found here on the forum and will see if that works. The EVAP delete and simplified vent are working great however. I'll make a post on the General forum later for any Zetec owners that may experience something similar.

I would appreciate more information on what was required for the swap as I intend to do the same eventually.

Thank you, Croc. No insult taken, and I appreciate verification on anything I post. I didn’t know understeer was the de facto behavior as this is the only Caterham I’ve pushed hard enough to find out, and I’m still learning how to dance with it. My expectation was that it would oversteer naturally and I would have to manage it. At Autocross I did a better job of balancing the weight, but didn’t do great every time and it showed. I’m no professional and still got much to learn. Yesterday I admittedly chucked it into a hair pin expecting Chapman’s hand to give me rotation. It’s good to know about the high speed understeer too, although that sounds like aerodynamics may be playing an effect too? Greatly appreciate you sharing your specs! Good to hear that you shim the rear as well. Are there a set of recommended shim kits? Could I bother you with sharing a picture of where you measure the ride height? I thought I measured it at the right place but every time I look I get more confused. I set it to 145mm front and 160mm rear with me in the seat, mainly because of oil pan clearance but it will be lower with 13s once I eventually do that.

Took the Cat to get an alignment today expecting it would be bad after raising it so much. It was kinda bad with -1.2* camber and 0.45* of toe-out up front, 5* caster. Rear was -1.5* camber and 0.1 toe-in. To help eliminate understeer I asked them to set the front to -2 camber, 0 toe. Went for a quick blat and it feels better, but it still understeers when pushed hard enough. I’m going to shim it to try and get 6 or 6.5 caster and try again. Next step might be trying to stiffen the rear roll bar but I would rather not because likely that the tires have some blame in this. At any rate, I’m loving this thing .

This is a common misconception about oxygen sensors and gauges. Oxygen sensors don't read AFR, they read Lambda. Lambda doesn't change with the type of fuel, and Lambda 1 is always stoichiometric regardless of fuel. The gauge converts the Lambda reading to AFR based on a user configurable setting which is a multiplier of stoich AFR * Lambda. By default this setting tends to be 14.7AFR = Lambda 1 for the gasoline scale we are used to. As a result, an engine idling with an AFR reading of 14.7 but running E85 doesn't actually have a 14.7:1 ratio in the exhaust, but instead 9.8:1 . The sensor is reading Lambda=1 (9.8:1 for E85), but the gauge has converted it to the gasoline scale. This of course changes if you modify the scale in your gauge. @Mudder The AEM X series gauges are good and reliable. Install the oxygen sensor behind the collector of your 4-1 header. It's also a good idea to wire the controller in such a way that it doesn't heat the sensor until the engine is running to prevent condensation from damaging the sensor.