So I got my car tuned at functiontuned and my car seems to be having some issues here and there....

1st off my check engine light keeps coming on and I found out code means "bank 1 running too rich".... I bought a scanner and erase it but now it is a daily process.... Comes on, and I erase it.... everyday.

2nd issue is when I take off from first or any other gear at low RPM, the car feels pretty boggy until I hit about 3500K... Is that normal?

3rd issue is cruising in 6th gear has become impossible because the power at low RPM is not there. If i'm not going 75mph, I have to be in 5th to have a little bit more power at average HWY speeds.

4th... not a issue but just complaining.... my gas milage sucks!

Other then these issues, the car seems to run very strong. Any suggestions?

 

.. need more details.... mod list.. etc.

 

Reading your sig, Fully built, tuned, 300hp Why didnt you just go F.I? But not trying to get into that, seems like a tuning issue, this is something you need to discuss with your tuner, as for gas miles, maybe cause you have a fully built motor? I dont know, update us and good luck

 

Wiseco Pistons 96mm/11. 0 : 1 Pistons
Eagle/SCAT H Beam Rods
ARP Rod Bolts
Block inspected and cleaned
Block redecked
Block Bored and Honed using a Torque Plate
Rotating assembly balanced
Crank magnafluxed and the journals micro-polished
New Moly coated Race Spec main bearings installed
New Moly coated Race Spec rod bearings installed
Block assembled
New OEM Head Gaskets
Heads inspected and cleaned
Heads redecked
Ported exhaust and intake runners
Oil Pump - VQ35 RevUp
JWT S2 Cams
JWT Heavy Duty Valve Springs
5 angle radius cut valve job
New OEM Valve stem seals installed
Valve Stem Heights set
Cold Clearance set for stock cams
Heads assembled
New OEM Rev-up Oil Pump
ARP VQ35 Head and Main Stud Kit
Z-tube
JWT popcharger
Copper iso thermal spacer
Strup Headers
Strup Testpipes
Fast Intentions exhaust
Unorthodox Pulley Kit
ACT HD clutch and pro lite flywheel

 

gonna go boost... just wanted to see what it can do NA first.... now a 3.6L

 

You're cams have totally killed power below 4000rpms. That's the downside to running cams in these cars. Cams are tuned to specific rpms ranges. The only way to develop any real significant HP gains without increasing displacement or adding forced induction is to increase operational rpm. This is usually done by increasing the volumetric effiency of the motor, specifically cams, intake manifold work, and head work. The trade off is often low rpm performance in hurt in order to make big higher rpms gains. I wouldn't be surprised if you car is missing 25 to 30whp over stock below 3500rpms. Maybe more. The bank issue you're experiecing is most likely related to the cams as well. You've totally changed the low rpm/part throttle operation of the motor with cams, specifically the emissions system.

That lightened flywheel isn't helping things at all either. You've lost a lot of moment of inertia which means 0-40mph performance will suffer greatly. With the cams and flywheel, it's probably bog city all the way to 50 or 60mph and then the car takes off. Great for big road course racing, but horrible for 0 to 100mph acceleration.

Did your tuner/builder not warn you about the downsides of all these mods?

 

^^^ don’t be too sure... with proper headers and proper tune (cam angle/timing) the low end issue "could possibly" be addressed... the cam he has is not real aggressive - not a real high lift...

I have not confirmed this yet with my car - but much research is being done and some tweaking will follow if/when I go this route.

One thing is for certain - there aren’t enough VQs doing cams and headers and definitely not many with cam timing to give definitive’s about the performance characteristics.

 

i dont get it though when i had my flywheel put in i didnt feel a sluggish off the line. it actually buckled me back in my seat (using bfg kdw2).. but yes after 40mph it really pick up especially 50 to 80mph i noticed the needle jut swings up ..

 

I'm with Dave on this one. I don't have cams, but I know from experience that running a lightweight flywheel, headers, test pipes, and exhaust all combine to make the car harder to drive. My car totally opens up at ~2800 or so, earlier than your but like I said, I'm not running cams.

BTW - stick your stock airbox back in for a couple of weeks.

Also - are you running O2 spacers in your test pipes? What code exactly are you getting?

 

wait so your saying it car drive harder. im running the act prolite flywheel.. It chatters till 1500k car really feels like it opens ~3000k and consistent through all gears..

Launchin from line on brand new BFG KDW2 and it spins for a blink of an eye and buckles down hard in first...n tugs the hell away before 3rd and beyond...
(everything other than headers is installed)

but i didnt notice a slower effect on the car... i got the act just a good friend of mine had it and it felt way more responsive than my factory flywheel



LEMME ADD I NOT DISREGARDING ANYONES BELIEF OR EXPERIENCE CAUSE I KNOW ALOT OF PEOPLE OUR ON THIS FORUM THAT SPEAK FROM THERE A**CHEEKS..

I am a stickler for noticing differences in cars..

 

Just go FI, then wait and see the #s, if it aint the right #s, theeeeeeeeeen you should start to really worry

 

All Trey and Dave are saying is that when you have a light-weight flywheel, you gain more drivetrain efficiency at the expense of bogging of the line due to the lack of rotational mass to launch you off the line (in other words, you have to rev higher to achieve the same launch).

With a similar effect, when you run headers, test pipes and especially aggresive cams, you are trading high rpm power for low end torque. In in other words, the torque curve basically shifts towards the higher rpm range, which means more power up top and less down low (since HP is basically torque x rpm divided by a constant).

I hope this will help explain your confusion about their statements.

 

makes perfect sense

 

3.9 FD might help?

 

sounds like you need to take it back to where you had it tuned and tell them that, there seems to be a problem.