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Re: Rah - JZX91

Posted: Sat Jul 06, 2013 2:52 am
by PSIBRG
Thanks for the offer but I should be sweet :)

Re: Rah - JZX91

Posted: Wed Jul 17, 2013 3:17 am
by PSIBRG
Sooo, was meant to take the car to a drift day this past weekend, didn't make it unfortunately :(

Got most of the shit finished on Wednesday night, primed her, and then fired her up. Started first pop and sounded awesome...

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Thursday was spent putting together the last bits and pieces and tidying everything up. We finished around 2am, hooked up a wideband and went out for a road test to make sure everything was alright. For some reason it was running super lean off boost, like 17:1-22:1. On boost was fine, around 12:1. We quickly bypassed the fuel computer to give the pump a constant 12v and went for a retest, was a little bit better but still around 20:1 when cruising with no throttle input.

We decided to call it a night and replace the 380cc injectors with 440cc Supra's the next day. After getting them in we went to fire it up and it ran like shit, coughing and spluttering. Little puddle of petrol on the runners, so I guess the o-rings on the 440s are fucked. Gonna pull them back out and get them cleaned and flow tested, and grab some new o-rings at the same time.

In the meantime, if anyone has any ideas as to why it's so lean off boost (idle/part throttle/no throttle) I'm all ears. Fuel/computer wise it's basically stock, 380cc injectors, stock ecu, stock 2jz fuel pump. It's fine on boost, a little rich even. I'm stumped...

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Re: Rah - JZX91

Posted: Wed Jul 17, 2013 12:55 pm
by Nathan Malmo
awesome thread man, loved having a scroll through your build! you've done exactly what id like to do to mine! (the engine/trans conversion, but being a starting uni student, ive only been able to do a few cosmetics so far, but in time! can't wait to see a vid of it out there! :D

Re: Rah - JZX91

Posted: Wed Jul 17, 2013 1:36 pm
by luc3unitJZX
I'm pretty sure it the map on the stock ecu that runs it lean on deacceleration. Otherwise you would just be dumping gas into the exhaust. Be able to tune fuel in with piggyback or standalone

Re: Rah - JZX91

Posted: Wed Jul 17, 2013 1:38 pm
by luc3unitJZX
And try get your on boost numbers down to mid 11s. Leave stock 380s and crank the fuel pressure a couple of psi

Re: Rah - JZX91

Posted: Wed Jul 17, 2013 3:06 pm
by PSIBRG
Nathan Malmo wrote:awesome thread man, loved having a scroll through your build! you've done exactly what id like to do to mine! (the engine/trans conversion, but being a starting uni student, ive only been able to do a few cosmetics so far, but in time! can't wait to see a vid of it out there! :D
Haha cheers man! All it takes is time and patience, it's taken me 2 years to get this thing turbo/manual. Can see the light at the end of the tunnel now haha.
luc3unitJZX wrote:I'm pretty sure it the map on the stock ecu that runs it lean on deacceleration. Otherwise you would just be dumping gas into the exhaust. Be able to tune fuel in with piggyback or standalone
Yeah but it shouldn't be this lean surely? Isn't it meant to run more or less stoich (14.7:1) at cruise? I'd be happy with anything up to 16:1 really, but as it is, on deceleration I'm actually maxing out the wideband (only reads to 22:1), and on part throttle cruise it's floating around the 17-18:1 area.

On boost it actually is in the mid 11's so that's fine... I'll be running the 440s cause I'm gonna be getting it tuned once I've sorted all the teething problems.

I probably should have mentioned, there's a nasty flat spot off boost. Also got a check engine light on deceleration during our last test drive. I'm guessing the ecu is detecting knock and pulling timing. Gonna pull error codes if it happens again. Hopefully there's a simple solution to my problem, stuffed knock sensor or something, but the engine came out of perfectly running car...

Re: Rah - JZX91

Posted: Wed Jul 17, 2013 7:34 pm
by luc3unitJZX
I think there complete deaccelration cut off, dont hold me too it, so youre getting it tuned, so will have piggyback??

Re: Rah - JZX91

Posted: Thu Jul 18, 2013 2:56 am
by PSIBRG
Hmm, you could be right, I'll look into it more...
And yup definitely getting it tuned, would be a waste to run this setup on the standard ecu. I have a e-manage ultimate, but thinking about selling it and going with a Link G4. Just means it'll be a few months more downtime for the car cause I'm broke as fark now :lol:

I just want to get it properly drivable before I take it for a tune so I don't end up wasting money troubleshooting problems when it's on the dyno.

Re: Rah - JZX91

Posted: Thu Jul 18, 2013 9:33 am
by Tofu
Don't bother with the Piggyback if you want a nice tune as the factory ECU will always fight against it.
You'll do a dyno run with a perfect map, do it again 10mins later and it's completely different!

For reliability i'd stay away from it. Especially since you have bigger injectors and a larger turbo.

Can't wait to see this thing out destroying tyres! I'm sure Dave is jealous!

Re: Rah - JZX91

Posted: Thu Jul 18, 2013 11:47 am
by luc3unitJZX
That's what I'm going to be running is a g4. Pricey as, by the time it's wired in and tuned ends up costing around the 5k mark, then you can run deacceleration fuel and a harsh limiter and pop some flames!!!!