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SR20DET S15 drift car

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Creating a little build thread here, mostly for questions as i go. Hoping to get some good input and help during the build.

The car is a Nissan Silvia S15, ex D1 GP car. Everything is pretty worn and sorely needs a refreshment. Everything in the suspension will be changed out with exception of the coilovers. Engine is newly refurbished. It has previously been running the same HKS Fcon pro since D1, but i have just bought a Motec M150 and new loom for engine management.

Just finished removing all the original wiring today. Going to wire everything from scratch.

The first thing i am uncertain about is the injectors and fuel lines. The car has previously been running 520whp on pump gas on 850cc injectors. I am aiming for 550-600. I am thinking the 850 injectors may be struggling to keep up? The fuel rail is also stock, could this also become a limitation?

Here is the chart from ID's fuel flow calculation. If this is correct my injectors will be at 98% duty cycle at 8000rpm (i plan on running up to at least 8000). The only input i didn't quite fully understand from the chart is the difference between a boost referenced fuel system and a constant pressure system. Would someone care to explain this in a little more detail? Anyway, i got an error when i put constant pressure system, so the data below is for boost referenced.

Edit: Noticed the picture did not work so here is the link: https://www.dropbox.com/s/gys2rmr1cx5edzm/Injector%20calc.jpg?dl=0

The car is currently stripped down, only the front suspension remains so i don't have any pictures worth showing at this time. Will post up some pics after i get it all cleaned. Many years on the track with oil spillage etc and no thorough cleaning sure leaves a mess in the engine bay!

This is by the way my first time doing complete wiring, and i have no previous experience with EMS tuning. I am hoping to be ready for the first track day at my local track in the mid of June, so lots to learn in a short amount of time. If i get way behind on schedule i may put the wiring and tuning away to a professional tuner, but i hope to do it all by myself.

A boost referenced fuel pressure system is one which the pressure regulator has a boost line attached, this allows it to increase the fuel pressure as the manifold pressure increases with the boost, it should be a 1:1 ratio, i.e. if you have a base pressure of 3bar and add a bar of boost your fuel pressure should be 4 bar, I've attached a chart of manifold pressure and fuel pressure Vs RPM, this is from a diagnostic session so you can see the fuel pressure isn't stable. This is usually the preferred system for aftermarket/older boosted applications as it keeps the pressure differential consistent.

A constant pressure system is exactly as the title says, it stays at a constant pressure no matter the manifold pressure.

Attached Files

Thank you very much for the clear up. So you are saying that for most applications, mine included, a boost referenced system is preferred?

Sorry for the delayed reply, yes for your type of car a pressure referenced system would be best/preferred

Nothing too interesting going on so far.

Gave her a good clean on the underside and engine bay the other day.

Subframe

Subframe after i welded in reinforcements for the diff mounting points and the mounting points for the arms. And some fresh paint :)

Subframe back in the car with new hubs, arms and solid subframe and diff bushings.

All new front suspension.

New swaybar with bent and adjustable end links for wheel clearance.

New ref and sync setup. Bye bye CAS.

I'm going to start wiring soon. Does anyone have links to good webshops with wiring tools/supplies? Suggestions on good fuse/relay boxes and setups would be appreciated.

Another question. I am fiddling around in the M1 tune just getting familiar with things. One thing i see i am going to need some help understanding is the ref/sync setup. How do i set up the ref/sync correctly to work with my trigger setup? The crank wheel is a 24 tooth with a honeywell gt101 sensor and the cam is a hall wheel. Can i use the Engine speed reference mode "Multi Tooth Four Stroke"? It says the following: "Four stroke engines with evenly spaced reference teeth on crankshaft and one synchronisation tooth.

Reference: magnetic or hall sensor.

◦Tooth pattern: Tooth Count teeth per revolution

◦Cycle lock position: edge before the synchronisation active edge

•Synchronisation: magnetic or hall sensor.

◦Tooth pattern: one tooth

•SIM3 mode: 10 - 1F"

For the sync it says "Tooth pattern: one tooth", but my hall wheel has multiple. How does the ECU know which one?

Here is a picture of the hall wheel

And here is a setup from the Haltech Elite, but i guess here they are using the hall wheel for both ref and sync.

Any help would be greatly appreciated.

Can you show some detail on how the cam sensor mounts and what it is using to trigger? Can that be modified to provide one pulse per cycle (that is one cam revolution, or two crank revolutions)?

Your best bet, is to find a mode that you can modify your triggers wheels to match, then use that.

Not behind a pc at the moment but i can take a picture from the install guide and post up later. On my previous post you can see the wheel temporarily mounted on the exhaust cam. In front of the wheel you can see a blind plug that has been taken out of the head, the sensor goes in there and will be reading the outer ring on the wheel.

I think i can take the wheel apart into two separate pieces and remove magnets, and maybe move them, but i'm not sure if thats gonna help.

Worst case i guess i can remove one tooth from my crank wheel and use only that?

Here are two pictures from the installation guide that shows the mounting of the sensor.

Ok. So if i understand this correctly. If i modify the cam wheel, take out all the magnets except one, measure the CRIP in crankshaft degrees between the one magnet aligning with the hall sensor and piston one TDC i should be good to go?

Did some digging. The wheel has an "extra" magnet, and the supplied hall sensor has two channels. So by just wiring up one of the channels on the sensor it will only read the home magnet.

Interesting setup with that hall wheel, never seen that before!

No updates in a while.

Here are pictures of some of the work.

Engine back in

Temporary marking of the loom

Got a spacer made to go between the plenum and the runners to give space to the top mount fuel rail.

Test fitting of the fuel rail. Bored all the injector holes from 11mm to 14mm to fit my Lucas injectors

Made a block off plate for the IACV, and fabricated a mount for the fuel rail. As you can see i am no fabricator, nor do i have the tools needed for this kind of work, but function over form for now so i can get the car up and running. Also got the bosch TMAP sensor fitted

Dual caliper setup fitted. 2x R33 GTR Brembo's, wilwood 0.625 cylinder and carbotech XP10 pads for the hand brake

Interior is coming together again with brand new takata 6 point race harness

Test mounting of the hand brake

Stocked up on tires for the season so i hope the car gets ready soon