Just finished my Vortech V3 install with 600cc inj 255 walbro and stage 0 frs it took awhile to start (had been left for 5-6months without moving). Will I be able to safely drive the car 230miles to my tuner when the afr at idle is 10.5ish?
Cheers

 

If I'm you, I'll rather put stock injectors back and swap them with 600cc at the tuner.

 

What are the AFR's when you're Driving normal? How does it feel?

 

you idle should not be anywhere near 10.5 with 600cc injectors. mine idled right at stoich with 600cc injectors on the stock ECU.

what did you set your fuel pressure to?

 

I asked the same question before. It seems that 600cc is near the limit of what the ecu can control in closed loop. When you accelerate anything other than very slowly you will run extremely rich since the ecu has no feedback control of the injectors in open loop mode.

230 miles is a long way, I would put the stock ones back and set the fuel pressure to stock or there about so you can see your AFR's at WOT. Does anyone know what the AFR should be on a stock engine at WOT? 12.5? 13?

 

Today was the first day I started it, so not driven it on the street and was in a garage getting carbon monoxide poisoned so didn't run it for long but I think the fuel pressure was too high ( from what my dad said it could have been around 60 (poor eye sight tho)) so I hope it was this high and I can adjust it when I roll the car out the garage eventually. I presume if I reduce the fuel pressure it should idle a bit better.
Thanks for the post, filled me with a bit more confidence.

 

Stock fuel pressure is 53-63 according to the Haynes manual. So your fuel pressure is around stock. I would definitely change back to stock injectors. Get the car outside, see how it runs, then if it seems fine. Drive it up the street and go from there.

 

From what I have been told/seen some guys on similar setups have an idle pressure of 43-45psi. So hopefully this weekend when I get a chance I will adjust the pressure down and reduce the overfueling issue. But has anyone driven their car with larger injectors without a tune to get to a shop?

 

I drove with 600cc but I had a base tune of 750cc I downloaded and it was just enough to get me there, i drove about 6hrs away. I didn't get into boost though. I know that would probably hard for you since its a supercharger.

 

You will run very rich on the stock ecu at anything except low throttle. Can they make you an approximate fuel map to upload to get there. I would take the belt off the supercharger so you can't boost.

 

Tow and then drive back home?

 

^this

 

^ that's your safest option

 

Yeah I know that would be the safe option but unfortunately none of my familys/friends other cars have tow bars or are able to tow me. Looking at trailer hire but is too expensive in comparison of booking a hotel and geting up early to change the injectors over in the tuners car park =/ will feedback on saturday of how the car drives once I have a go reducing the fuel pressure.
Damage that can be cause from over fueling? Destroy cats(replaced with de-cat so not a problem), cylinder wash/scaring? Ruin the spark plugs anything else?

 

Cost of towing vs cost of rebuild....

I'd either get a safe base map loaded or tow the car.

 

Dude, I had that exact setup for 3 years and ran on stock ecu, stock map, 600cc injectors, idled at stoich, and hit normal targets under easy driving conditions when i drove it 400 miles to the tuner.

Do you even have a vortech car? If not GTFO!

 

Depending on how rich you are would depend on the damages, the usual thing is just fouling out the plugs. Have you start/drove it since you started it that first time?

 

I do not. I plan to but at the moment I do not. Not having a vortech supercharged 350z does not diminish my knowledge of modern fuel injection however.

If I am wrong I am more than happy to admit this. My understanding is that like most modern EFI systems the ecu is designed to use set tables to determine injector duty cycle under moderate to open throttle conditions ie open loop mode, not using the stock oxygen sensor for feedback. Hence I do not understand how you could hit the correct air fuel ratio targets at moderate/WOT when the ecu was programmed for much much smaller injectors and no correction occurs. In closed loop mode using the stock oxygen sensor for feedback correction it makes perfect sense that the ecu can automatically reduce duty cycles to account for the larger injectors ie at low load.

Either the 350z does not work like this or I cannot explain your personal experience. Please let me know.

 

Thanks for the response, I have not started the car since first start up as I need to put the wheel arch liners and wheels back on to roll it out the garage before I start the car again. If I can get the car to run like yours I will be happy to drive it down, just to confirm do you have tuner kit like myself?

Also forgot to mention my car is a JDM and dont have a OBJ connection or know if my tuner can send a UK car base map to put on my JDM ECU. (Not many uprev tuners in the UK thus having to drive quite far.)

 

Just to kill this thread, managed to get the car running good. fuel pressure now 43ish, boost -22ish, and air fuel 14ish. drove round the block and seems fine to drive, just keeping out of boost.
Got the dreaded vortech rattle at idle rpms so will need to get this raised when uprev is done.
http://s1168.photobucket.com/user/ev...baaf3.mp4.html
http://s1168.photobucket.com/user/ev...99450.mp4.html