Ditched turbo ZX ECU for SDS :-)

I'm working on a customers 77 280Z that I swaped in a spearco intercooled ZXT engine last year. He wanted to use the stock ZXT electronics even though I warned him not to. Well after a year of fighting with it and it's problems (he lives in another state) and trying a RRFPR etc to get it to run good with more than stock boost, he gave in and let me rip all that garbage out.

He didn't want to spend the money to fabricate a crank trigger so I set it up with a fuel only SDS system, some 440cc/min injectors, removed the RRFPR, used a stock 77 single pickup dizzy and an MSD BTM ignition box. I set it up with 40 deg total timing without vac, ran the vacuum advance off the TB and set the BTM to pull out 3/4ths of a deg per pound of boost.

After about 20-30 minutes of tweaking the fuel curve from some base sample maps at the SDS site, this car runs so much better it's unreal. The off boost power is fantastic, the drivability is MUCH better than any ZXT ECU'd car I've ever driven, strong throttle responce and has great power at 13PSI with no detonation using the stock turbo/engine. Of course in hot weather he may have to run more boost retard, but that is there at the twist of a knob, instead of having to retard the WHOLE curve with the stock ZXT system manually turning the dizzy which kills all the off boost power etc.

I'm convinced, the stock EFI system doesn't have nearly enough ignition timing dialed in for off boost use and since it doesn't use a map sensor, it can't know when to do that (or pull it out) if it wanted to. Anyone who argues this ZXT stuff works even decent, has never seen the difference using a setup like this makes.

I don't think I'll ever let someone make the mistake this guy did using the stock ZXT ECU again. If anyone here is doing this swap, --SERIOUSLY-- consider selling all that crap on ebay to at least partially fund a setup like I used on this guys car or use the stock early EFI with a BTM box and bigger injectors! I do love how easy the SDS system is to setup and adjust, I had the car running great in about 20-30 minutes driving it less than 10 miles. This is a no brainer in my book.

BTW here's some shots of his car, will have the most recent to upload this weekend. He's got a super nice turbo Z

<http://atlantaracing.tripod.com/turboz/page3/morepics.html>