The 440s while they could have been tuned with the Unichip I decided to go 400s because after some good advice I felt that would be sufficient. While the car was drowning rich with the 440s the 400s cleared it all up and the car is running great. I have the WMS intake and runners on order and after they are installed I will do a custon Unichip tune. Then I am done with the engine.

Special thanks to Peter at M7 and Josh at Unichip for unbelieveable service and advice. Peter I should have listened to you in the first place...thanks.

 

Great news for you. So, what unichip map are you running? One Josh provided?

 

Yes...Josh providd me with his best guess and it is doing pretty well. We may do a custom fter the intake manifold is in

 

Is there not a Unichip tuner near you Spider? You absolutely should be getting yours tuned on the dyno by a licensed tuner with the amount of mods you have. Well worth it!

 

The closest one is Hesco in Birmingham and they did a dyno tune for me. I am going to do a dyno tune after the intake is installed . I am working on flying someone into Atlanta for the tune. Airfare is cheap to Atlanta


The engine is screaming after 5k but the low end needs to be tuned....it's taking to much time to wind up. I want a few more pistons in this engine....I really want the low end to come up. I see these guys with torque numbers that are hard to believe for the mods they have. Either I am not doing it right or there are some squirly dynos out there or both.

 

I just put a 19% pulley on with the JCW software and the cars haaaaaaauls ***....My injectors r goin in tomorrow to get somemore fuel cuz it sounds like its detonating on the top end. Im yankin 350z's a new *** and STI's ( from a roll ) . I should be getting it dyno'd in a week or 2 so ill post the results then

 

Im confused on why people have the need to go with bigger injectors.

What tuning have you done to compensate for more fuel b4 you did a injector swap.

 

Injectors are only reliable up to about 80% of their duty cycle [the amount of fuel they are rated for]. Adding a pulley, CAI, etc will increase the amt. of air in the combustion chambers, which requires that fuel be increased too or else there will not be enough fuel to combust efficiently. That is why injectors with a higher output are added, so that the engine will not lean out. Leaning out causes pre-detonation if bad enough [gas combusts before spark due only to pressure], which will ruin your valve seals.

 

Detonation ruins the components in the combustion chamber ( pistons ).... valve seals are not in there nor would i think they would be harmed. I can see leaning out is an issue but you can lean out any engine ( injectors shouldn't matter ) without the right tuning ( fuel mapping ) . But this falls back on....WHO came up with the fact we need bigger injectors just because were adding these mods? And where is everyone coming up with there conclusions on what size to use?

 

jcw has larger ones dont they?

 

380cc. Retail $113 ea.

 

larger than stock though, no?

 

I put in larger injectors because the dyno wide band showed me running a bit lean and the Unichip had no more headroom for more fuel with the injectors that were in it. A very practical solution.

 

Yes

 

 

And why did you change out your larger ones for smaller ones?

 

Thats what i wanted to know......An injector will only put out as much fuel as you tell it too so changing it to a smaller one wont really fix your over fueling problem.....the chip is whats messing your car up and giving you to much fuel.

 

I dont know half as much as most of you, still learning b4 i say much but... i would just think naturally that if the engineers that made the jcw kit think it needs bigger ones, than so would mine with similar mods plus some. simple logic, maybe off but idk

 

Absolutely, the 440s needed a new map....which would have been a hit or miss scenario because there is not a Unichip tuner in Atlanta. This means I have to send it off and get a best guess from someone. This has proven to be less than desireable in the past. I looked at what Randy and a few others were running and they were running 400s. I figure if their engines ran well with 400s with similar if not the same mods...mine probably would too. I also noticed a few posts about people having trouble with 440s. Not wanting to bother with a custom map at this point because I am waiting on a modified intake and runnners and will do a custom tune after it is in, I made an "educated" guess that if I went o 400s (the 440s were drowning the engine..ran like crap and there was a "rich" code) that it would work fairly well. I was right...the engine with the 400s and no new map is running very well......waiting for the intake etc.

 

kewl

 

Hubie was the first to report using larger injectors for his initial twincharger setup. He then put 440's in my rig, using the apexi to trim them back at lower rpm's and high rpm', reading power and A/F on the dyno. 400's would have had enough headroom, but you still need a way to trim the fuel.

 

YEP

 

aaaaaaaaaaaaaaaaaah w/e