Grimspeed crosspipe

**archer1.8** · #1: 12-23-2012, 12:58 PM

This past week I got a set of STi manifolds from my buddy. I ported them and kept the stock crosspipe. I also installed an STi UP, Bosal DP, and went stage 2.

This thing spools at 2000 RPM's now. It use to spool just around 2750 rpm. Spooling at 2000RPM is way to quick and it is killing my gas mileage

MY question is will a Grimspeed Crossover make the turbo spool a few hundred rpms later??

**underground000** · #2: 12-23-2012, 02:15 PM

no because it is ported out
protuned stage 2? if not then thats why you're burning gas, open source/ots tends to run rich. or talk to your tuner and he can make it spool a bit later.... hmmm not too many people complaining about turbo threshold too soon

**archer1.8** · #3: 12-23-2012, 02:38 PM

Yea it could be that it is running very rich. I am running the 91 octane map, should i bump it up to 93? Yea its only bad because i cant drive the car at all without it being in boost.

Hella fast tho

**archer1.8** · #4: 12-23-2012, 02:42 PM

yea i have a V1 accessport so a protune would be hard with that

**archer1.8** · #5: 12-23-2012, 09:09 PM

ok just got back from a 100 mile round trip with mixed driving. averaged 24.3mpg...thats better than i got when I was stage 1....maybe the ecu is learning more?

**underground000** · #6: 12-24-2012, 12:23 AM

93 tune would make you run more timing most likely and if you're not using 93 then you can kill then engine. run a log and see if youre knocking. i knocked a lot when i was OTS stage 1 & 2

I'll say sell the AP and get a vagcom cable for ~$20 and get a real tune. the OTS is not made for your headers, and youre complaining about bad gas mileage because youre running OTS map which purposely runs rich. the turbo comes on so quick because thats what people want when they go stage 2, a tuner can fix your 'problem' youre having

**iNVAR** · #7: 12-24-2012, 06:55 AM

You know, someone in another thread mentioned this phenomenon before... the turbo spooling quicker causing gas consumption to go up. I can't remember who it was but it was someone whose opinion I respected. They had a larger turbo, and they said they got better gas mileage on the highway because the threshold was higher on their larger turbo than our stock VF40.

If the turbo spools up sooner, thus producing more power, why don't people just back off the throttle to stay out of boost and not accelerate as hard?

Maybe something's not clicking in my head here...

**archer1.8** · #8: 12-24-2012, 12:53 PM

I know zero about the vagcom cable E-tune thing. I need to do more research.

Yea i did my best to stay out of boost but when it is really hilly its hard to drive under 2000rpms