Over the past couple months I’ve been getting the fuel setup organised for the S13.
It is a pretty simple setup, nothing worth millions of dollars. I didn’t have a fuel tank or a boot floor anymore, so I needed a frame, a fuel tank, a surge tank, some pumps, lines and some fittings.
I went with a 48L (12 Gallon) Jaz poly tank with a recess at the rear. They come in a variety of sizes, they are quality pieces and they had an option suited to my setup.
To help with fuel stability I’ll be packing it with foam so the surge tank doesn’t have such a hard job.
One of the more expensive bits to the fuel setup was the fuel rail. I had a few options to think about, taking into account what I’ve used in the past and what I could make work. Options were a Plazmaman rail, HKS rail or a new Tomei rail. All 3 are top quality bits, some more expensive than others. I haven’t had much experience with Plazmaman or HKS so I thought I’d stick with the name I’ve used before.
An unused Tomei rail popped up for sale in Sydney and it turned out to be a lot cheaper than buying it brand new. For obvious reasons I grabbed it, the only things missing are the pair of spacers and bolts to mount it which is easily fixed!
Pumps were an easy option. I wanted an external pump and one that wasn’t super loud. Walbro 255’s are quiet, inexpensive and will do the job perfectly. I went with two pumps so I’m not running a single pump on the limit when I’m driving. This way they will be under a lot less load, which means they will last a whole lot longer.
One piece that I was in two minds about was the surge tank. I was always going to have a tank with a recess and would also mount my pumps below the lowest point of the tank. But, I wasn’t 100% sold on the idea. What would happen if I was down to ~2L of fuel and driving the car really hard? Obviously fuel would move to a corner of the tank and the pumps would starting leaning out. I’ve never used a surge tank in the past purely because I’ve never needed one. I know how they work and I know the advantages, but I was never keen on spending extra money if it wasn’t needed. Long story short, I bought a 2.5L surge tank with twin pump mounts.
Buying the parts is the easy part. Then you need somewhere to mount it all. That’s where this bit comes in.
I needed a complete rear frame to hold both the fuel and surge tanks, but I also needed a jacking point around that point to change wheels. So why not incorporate all of it into one piece? Also added a bit of strength to the rear of the car so if I crash into something it will take most of the impact. I’ve since changed my mind about the surge tank tube, instead of being 30mm in the photo, it’s now 40mm to match the rest of the frame. And I’m mounting the surge tank facing down not up, that way I don’t have to run a lift pump.
Last things on my list are fuel pressure regulator, injectors and some lines. I have the day off work tomorrow so I’m going to pick up the injectors, get some lines and try to get heaps of work done on the car. FPR should be here in the next 2 weeks I hope, then I can make sure everything is plumbed properly and get it mounted in it’s final position.