Ok I guess these are better than regular dykes (that's what I normally use, and I'm pretty sloppy and could just cut the ends closer)? I will definitely consider it but I should probably go back and cut these closer with some dykes to begin with.

 

Hmm that's an interesting point and something else to think about... I will definitely look at how close the exhaust is and if it's a problem. Not something I thought about at all or considered but would make sense if it's cooking the tank that it excessively raises the pressure and causes more fumes..?

 

Ya I'm pretty sure I'm running the DW200 sock. I posed the questions on facepage and seems like it's hit or miss with some people regarding fuel starvation. A couple people said the switch to a walbro solved the problem, whereas someone else said running a Holley Hydramat was the real fix. Did any tracks have a long sweeping left hander you visit Zak? I think I recall you have a long right handed sweeper. I haven't touched anything close to the pump hangar so I should probably inspect those. Based on the gas smell in my garage I think the vent is "working," the issue is just how to make it less strong the odor. I will check it though thanks.

 

IIRC, the DW200 fuel sock may be the same shape as the OEM one? Would have to look at a picture again to check. I remember running whatever sock came with my pump and it looked the same as what came out of the car.

We do have one track that has a super long (9-10 seconds) sweeping left regardless of being run CW or CCW. I'm actually fuel starving there at under 3/4 tank in my current car ever since going e85/turbo. The NA never had an issue, though. I should look into a Hydramat a bit more...

Wish I could help more with the odor concern. I've got the same general evap setup as you (tank venting straight to atmosphere and no canister/canisters), and haven't experienced the same thing in my small garage. I'd think it's gotta be the exhaust heating up the tank and causing pressure buildup like Six said...

 

I will literally Venmo you $3 to go buy some .

Death by 1000 cuts


Peace and harmony

 

Even if there's space between them, if there line of sight then the radiant heat will cook the tank. And the diff, and the trans.

 

Ha ok you made your point! I will DM you my venmo now. I guess sometimes the extra sticking out provides me some mental reassurance in case I need to adjust it tighter in the future I can grab it with some pliers and tighten it? I'm grasping at straws, I know..

Oh for sure. I will have to take a peek under there and see how much surface area is close to the tank and what the possible solution is. The easiest solution is just header wrapping the sections that pass close to the tank. A nicer solution would be making some heatshielding material out of the embossed Al, but I'll have to see where I could go about attaching it to the chassis.

 

I'm just giving you a hard time... but they are worth it.

 

I have a small pair of side cutters I use for that purpose, and I grappled with your dilemma too. At first I would cut them long, telling myself I will come back to trim when I am certain I don't need to tighten them - but I never tightened them, and never came back and trimmed them either. So now I just pull them tight, trim them, telling myself it's only a zip tie FFS, cheapest item on the car by a country mile.- and I don't think I have ever had to replace one because it was not tight enough.

 

Happy to report I bought some cutters from Wuhan Freight and my zip ties are all trimmed now!

I also made a boost leak tester and found one clamp that wasn't quite straight and tight enough so fixed a minor leak. Been meaning to do that and finally got it done.




Not too much else to report. I'm not sure if I mentioned it but I swapped the fuel pressure sensor to an absolute pressure sensor rather than a relative pressure sensor so it would more accurately report to the BMM ECU for fuel pressure compensation. I turned it on in the tune. When swapping the sensor I clearly didn't quite tighten it down enough as I just noticed earlier this week it had a small fuel leak there. I'm sure that's partly why the fuel smell was so bad (maybe the tank vent isn't that bad afterall), I'll report back after driving it a few times but that would make sense. I used teflon tape this time rather than paste (not needing to wait for it to cure is nice) and it's not leaking anymore.

I spent some time tuning it a bit better since I switched fuel pressure compensation on but it's pretty good. So hard to get things "perfect" as temperature changes, things heatsoak, etc..There are of course a few minor things I should address one of these days like the fuel starve when < 1/2 tank on left hand sweepers and I need to get more rotation out of the rear (it's at full soft on the front swaybar and full stiff in the rear) as it pushes a little on throttle, but I'm focused on the honda and making the exhaust at the moment so I'll get to it eventually. I think the Miata might need a stiffer rear spring as I think the staggered spring rates were for a "no aero" setup by SM, but it's not bad and minor.

Here's an obligatory pic with the trimmed zip ties.

 

Minor updates are good updates! Glad the issues have all been minor quips. Well I guess a fuel leak isn't a minor quip but at least it was a quick fix haha.

She got any track days planned in the near future?

 

Ya the fuel leak was pretty minor in that it was right in plane sight and easy to fix. Fortunately the fuel lines are on the intake side of the engine so not easy to touch hot stuff and start a fire.

I'm going to do a couple weekends this fall. Really looking forward to it. Shenandoah at Summit Point is maybe my favorite track and I'll do the late fall event at Dominion again. I wanted to do an event this spring but it's pretty hectic with birthdays and events around the end of the school yr for the kids so I opted to wait till later. Last year was so hot at Summit Main in June I don't really have any desire to cook like last year so I'll wait for the fall. I should be able to fix the fuel starve issue before the early October event. It seems like the "best" fix is probably a holley hydramat, but some folks have reported using the OEM filter sock and a walbro pump.. Not sure what I'm going to do honestly but if anyone has 2 cents feel free to throw it in.

Learning to TIG is kinda fun. Quite frustrating as I turned 45 and realized my near vision is going to s**t. I couldn't realize why I was so bad till I realized I couldn't see things clearly. Now at least it's doable. Gonna be real nice getting the Honda all sorted as well. If anyone has good tips for fab work I'm all ears. You can pop over to my thread on s2ki or chime in here. It seems like an angle finder measuring the angle between planes and then cutting mandrel bent tubing is the way to go. Pie cuts seem like they aren't terrible either but obviously requires more welding. Got some good advice from facepage on how to improve my welds and just need to practice a bit.