TheZprojectRed

hey people.ok i need opinions.. i just dropped 3,500 with getting the hks v-con pro and tuned on my greddy twin turbo 350z.. i previously had the greddy E-manage with the TT kit installed..and with that set up..i made 340whp and 331wtq on a mustang dyno...ok so NOW the NEW numbers are 352whp and 318tq... and with the old set up i was running 8psi..now im running 9.5psi.. reason why im on this thread is..can anyone help me with why i lost that much tq?? i spoke to the tuner which is a very well known tuner and he said since i didnt get the A/F knock amp which helps detect knock.. it pretty much didnt help him make the car into its full potential..his assistant told me that he was pretty much tuning the car blind without the knock amp.. i honestly thought my numbers would be better especially with 9.5lbs of boost..any opinions out there?so im a bit disappointed that i spent so much and didnt make more than what i expected..oh and btw it was about 80 degrees outside and i think my last tune with the old numbers it was maybe in the mid 70's.. thank you for your time to reading this..any opinions may help ..

350junkie

iTrader: (5)

get the knock amp?

Chris@FsP

iTrader: (4)

Does your tuner not have his own Knock Amp or other knock listening device that he can wire in for tuning purposes only? 1 hr labor to temp install the with quick disconnects so that he can re-connect easily for future tuning.

str8dum1

iTrader: (11)

the knock amp is needed for wideband O2s as well. But ,the tuner shouldnt have been blind if he had at least a tail pipe O2 sensor. If he had no wideband feedback, well you shoulda never taken your car there for a tuning to begin with..

A HKS tuner would have to chime in about the validity of your tuners concern. Sounds like rubbish to me

Nexx

iTrader: (41)

can you list all your other mods?

Chris@FsP

iTrader: (4)

His dyno should have a built-in wideband.

vdemon311

iTrader: (3)

go to a different tuner asap

TheZprojectRed

ok well he did have a tail pipe 02 wideband sensor.. but that was using only one bank.. here are my mods(greddy TT kit 18G,walbro 255l fuel pump,turbo XS race pipes,greddy true dual catback exhaust,hks v-con vpro. and i think thats it..oh and turbosmart boost controller, and hks ssq BOV..not that it matters..) so ya that is the list of MODS that i have.oh and im still on the standard 440cc greddy injectors..he said he used 120% of its duty cycle which is really high..he said that with a better fuel supply and A/F knock amp i wouldve made better numbers.. but still..i gained 12whp and LOST 12whtq.. i would rather have just stayed at 340whp and 331whtq.. i mean the car does run a bit more smoother but not really in a torque kind of way..

GreenGoblin

iTrader: (6)

Get a different tuner asap. That excuse it pure crap.

TheZprojectRed

well i was told timing wasnt there with the Emanage and now that i have the Fcon there is timing ..but still my brain is boggled by that..i need detailed info about whats going..but i appreciate everyones opinions!!

_ink

iTrader: (2)

I think its a tuner issue here, also think of it as piece of mind as the Emanage is not recommended in the tuning world for FI setups. You should feel good that your timing is sorted out and as you stated the drivability is smoother. These 2 points alone are already worth the investment you made.

Also remember that the dyno is just a tuning tool, you can't get too caught up in the numbers. Too many factors will lead to different results unless you have the same tuner, and that same tuner has a state of the art dyno room with wind tunnel and ambient temperature control etc.

jonnylaw

iTrader: (3)

Get the AFK and possibly look for a new tuner (like other have said). If you do get the AFK, make sure it is properly installed to detect knock and pull timing, and not just displaying A/F. The new AFK can display both banks, buy you'll need to buy 1 extra sensor.

binder

iTrader: (8)

if you're using 440's with nothing to bump up pressure (rising rate regulator with return system) you might be pushing the injectors. 120% i doubt, but probably up by the 90's.

with the potential for your setup i would get at least some 600's and a stage 0 return system. Hell, you could get better fueling just by using a stage 0 return system from CJM since it has a rising rate fuel pressure. You'll be able to use more of those 440's.

TheZprojectRed

ya im sure the injectors are maxed out..because i spoke to various performance shops with my set up and they highly recommended larger injectors..because they predicted that the injectors i have now would be maxed out from its duty cycle. so yea my next upgrades are going to go with some large injectors ,AFK amp, maybe a fuel rail kit,and fuel pressure regulator,..

binder

iTrader: (8)

CJM stage 0 is only like 380$ or something now. It's crazy not to pick it up. And then as you move up in power you can always upgrade to stage 1, stage 2, etc from them. Charles is a great guy.

injectors, 600's will be plenty with a stock block. You can pick up dw 600's for a great price around here.

about the knock amp, i'm not sure you really NEED it since you won't be doing tuning yourself. If you're having a professional tune it he should tune it with no knock, then don't mess with your map and you'll be ok.

jonnylaw

iTrader: (3)

^^If he's got a v-pro, then it can only be tuned by a pro-dealer and v-pro maps are locked and do not allow for any user adjustment, so OP can't mess with the map even if he wanted to.

Even the best professional tuners can be aided with a knock amp--the tuner can connect headphones and listen for actual knock when tuning.

It is also an additional safeguard measure if things ever go wrong/bad tank of gas, etc. It's a worthwhile investment and I would recommend it--it wouldn't be much more than the fuel system. But I would agree that his fuel issue(s) should be addressed first if money is a limiting factor.

binder

iTrader: (8)

it's not a safeguard. Unless they changed it the hks knock amp only displays and records knock. I didn't know it did a single thing about the knock it sees. You would need something like a J&S safegaurd that actually pulls timing when it detects knock.

That warning light/buzzer going off and you taking your foot off the gas won't happen fast enough at high rpm/high power to save your engine.

Blck350z

iTrader: (10)

Depending where you are in austin.... JTran Studios in Houston is a very reputable installer/tuner.... Maybe give them a call and see if they can help out?!

https://my350z.com/forum/forced-indu...-underway.html

mx594

iTrader: (4)

There is no such thing as 120% duty cycle. At 100% duty cycle the injectors never close...they are just wide open. You can't do better than wide open! Not to mention you should never run the injectors at 100% duty cycle for very long because it is very hard on the injector driver circuit, and it leaves zero headroom for atmospheric changes.

Blck350z

iTrader: (10)

^^ I was also thinking this...how can you have more than 100%??? but I did not say anything because I am not educated enough with injectors etc.... to back up my statement....