LS1 ECU to 240SX S13 speedo

There has been a lot of mis-information on the web about exactly how the S13 gauge cluster operates.  Hopefully this article clear things up.

First of all, everyone that said 2k, 4k or 8k ppm for the gauge cluster is wrong. 60Hz AC sine wave, ~3V p-p into Y/L with Y/B grounded gave me 13mph.  This means the gauge cluster needs 16,000 pulse per mile by the following calculation:

60Hz * 3600 sec/hour * 13 mile/hour = 16,000 pulse / mile

You also don’t really need a Dakota Digital box, unless you like to blow $70.  Reason being the LS1 ECU can be configured using HP tuners to give the correct 16,000 PPM output.  (VSS Output Pulses per mile)

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However, the LS1 ECU send out a DC square wave, 12v p-p.  It looks like this:

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The s13 gauge cluster needs to see 0 crossing on the Y/L line.  Instead of using a dakota digital box, go to radio shack and build this.

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The  circuit is not all that complicated.  I crammed it all together, put some heatshrink tube around it and tied it into the main dash harness.

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Voila!  Although it is not a perfect sine wave, the s13 gauge cluster will happily give you an output using the following waveform.

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Beware of people, not eBay

It used to be cool to roll with the windows down in 100 degrees of heat, knowing that saving 40lb from not having AC is awesome. Not anymore. How can I drive when I’m sweating faster than the US budget deficit increase?

Unfortunately, some idiot decided to yank out all the HVAC pieces and sent them to the dumpster in St. Louis. No worries. People are parting out 240s all the time. I bought me all the interior HVAC stuff from a dude on eBay for $175 shipped. For $175, you would think the guy could at least throw some newspaper in there to pad the box. I guess someone is cheaper than I am

Naturally, the pieces got a little beat up. I thought no sweat, a little duct tape never hurt anyone. It was before I spotted these little critters crawling around

Good god, what kind of person let fleas infest his car? This really put me over the edge. Damaged parts ok, I can deal. Fleas crawling everywhere? No. Homeboy total refused to fund me the $175, stating that damaged shipping is not his fault, and one can expect fleas from “slightly used parts”.

You might say wait, you bought this through eBay / Paypal, aren’t you covered under their buyer protection program? Well yes, but lets remember eBay / Paypal only makes money if you complete a transaction. I filed a complaint and am still waiting to hear back after a week! Ended up picking the phone and calling Visa. Got my money back with in a day. What did you learn?

Do not trust anyone
Never pay paypal transactions by bank transfer. BOA can care less about how you got screwed

Gah, too short

As part of the garage re-org, I moved the work table to the back of the garage (where the tire racks used to be). The floor drops off 6 inches right where the table ends, so I end up being 6″ shorter to the table than before. Good thing I had a giant pile of 2×4 from taking down the old shelves and a box of 3″ deck screws. How about an indoor deck?

The shot shows the deck 50% done. I added additional planks down the slope afterwards. The complete product was nice to walk on bare feet, and smelled good.

Cleanness is next to godliness

Before getting to involved (or re-involved) with the car, I figured I take a good solid month to make sure my working condition is acceptable. The 2 car garage will never look like that of a real shop, but some part of me really wanted things to be organized.

After some research, I decided on the 36″x18″x72″ wirerack shelves from Target. These bad boys were on sale for $36.99 a piece. Why not, I walked out with 6. Some serious elbow grease and the garage is looking much better.

Proudly made in China

Sometimes in life you need quality hardware. Hand tools, welder, beer… For everything else, there is Harbor Freight:

How does it work? Great! The only problem is the 36 grit wheel must’ve been made by someone who came to work with a hangover, because it was about 10tho out of round and makes the grinder walk around. Time to buy a dresser… where is that coupon?!

Scrap VQ35HR IM, but…

If I was going to make a hood hump, I’m going to stuff something cool down there dammit! How about VG30DE style, custom designed dual plenum intake manifolds? and there is even some remote chance that they will fit under the hood without modification!

Intake Manifold

Now this would be a truly custom part… VQ30DE-K mounting flange with RWD style IM…