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Discussion Starter #21
Wow, that's technical...but sounds like you're happy with the results. I need to first check the VVT solenoid, then proceed...
 

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It seems to be struggling in the higher RPMs.
and have you checked your rev counter is correct? They can under read
to check cruise in 5th gear and you should be reading 1000 rpm per 22 mph (the speedo is probably off too, another S4 weakness so use your sat.nav)

...mine never went over 3000 till I had it repaired...now (also fitted a squadra) I gotta be a bit careful as it feels much more willing above 4000:)

VVT test: to properly test your VVT, remove the two spade connectors from the vvt (under a rubber boot) and when the engine is idling, apply 12v to these connections and hold it there a few seconds........your engine should idle terribly rough, almost stall in fact.
If this happens the VVT is working:)
 

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But Mad North-Northwest
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Yeah, that's a good catch. I generally assume all the monopod tachs are quite slow unless they've been repaired!
 

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Thanks I will check it. What elevation do you live at and what octane are you using?
me?
I am in Köln, elevation about 60 foot sea level....not a lot;)
I use sometimes 95 (US 91) or 98 (US 93) octane here....the eu 98 is quite a bit dearer.
you can also get 100 or 102 here.
 

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But Mad North-Northwest
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So it depends on the car: every individual engine has slightly different octane requirements, which is why the stock timing maps tend to be on the conservative side. Squadra recommends US 93 (Euro 98) with the chip.

I tried the Squadra on my S4 here in California where best we can get is 91. It worked as advertised for torque, unfortunately it caused to much engine knock under load to keep it.

Some folks here in CA claim to have used it successfully. Either their engines have lower octane requirements than mine, or they're not noticing the knocking.
 

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Discussion Starter #28
Interesting how octanes differ. Any idea if at 3000 feet elevation the octane required increases or decreases? A gentleman from Denver mentioned 91 works well there, at 5000 feet.
 

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But Mad North-Northwest
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Generally octane requirements drop with altitude. That's why they typically sell lower octane gas in the mountains.
 

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Discussion Starter #30
Thanks, maybe the squadra will work at 3000 feet with 91 octane, good luck to me. After determining if the VVT is operating correct l will install the chip. Do you think removing the catalytic converter will get results?
 

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But Mad North-Northwest
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Well that would be illegal under federal law and also kind of a jerk move for the environment. But beyond that, no, it doesn't cost you much HP.
 

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Hey Billghon1

Are you sure your fuel injectors aren't clogged from age ? Have they every being off the car?
Bye
 

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Discussion Starter #34
The car has 52000 miles on it and it's been serviced religiously. But I don't think that the fuel injectors have been off the car. If Idols perfectly it starts perfectly. It runs great. It just seems to struggle in the high RPMs and maybe that's just all the pollution crap that's on there.....
 

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your main hold back in making power in the upper rpm's is the fuel injection system itself... the air meter box, just like " L " jet, the flap( air door ) maxes out at about 4500 rpm, at that point the door id fulling open, and all its doing is flowing fuel at a set rate. not accounting for more air passing thru the engine at higher rpms. the o2 sensor is trying to help, but the motronic system has limitations
Reattach the spring on the cog gear 5 teeth looser. When the air flows the "Flapper" door opens , but now it's wider and hits WOT !
 

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this is why when I had my oem engine in my spider I installed a 'LH ' system in the car..lh is digtal,,also lh has air mass meter , motronic had a air flow meter, less effective., I did notic a bump in performance when I installed the lh system, and on a dino air fuel mixture was great up to 6500 rpm. mo leaning out. I did my homework on this when I did the change over
Could you please detail where an "LH" system can be purchased, and is it a rather "plug-and-play" installation?
Thanks.
 

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Wrong, now it just goes full open easier.the ecu has no clue idea how much air is flowing into the engine.think about it, once that flap goes fully open, air fuel ratio goes out the door, how many cars you see nowdays have a l jet systems.
 
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