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FNK
03-05-2011, 08:19 PM
Would 7000 rpm be catastrophic for this engine?
I just came across this Chip tuner and wow 7000 seems high for a V6, then again it's only 500 more from my current 6500...
Past 6000 the power fall, I can feel the engine not pushing as much, I guess valve float... so 7000 is pointless!?
UNITRONIC (http://www.unitronic-chipped.com/main/en/files/90_2000-2001_audi_a4_b5_28l_30v_190hp.html)

To confirm, I came across this RRI Dyno Graphs (http://www.rri.se/index.php?DN=29&List=A-B)

What do you think? It's not a valve float or I should consider that chip and upgraded springs!?

FNK
03-05-2011, 08:35 PM
I found some infos, A 2.8 Passat chipped with unitronic (http://forums.fourtitude.com/showthread.php?3175360#post39714681)
But I'm still wondering about that valve float... or the gears been out of sync with the shift points at WOT

FNK
03-05-2011, 08:45 PM
This thread is now starting to look stupid as I end up answering my own questions...

The more I think of it, the drop of power past 6000 rpm seem like a restriction from the intake air flow or exhaust scavenging.
As I intend to mod the intake and polish the exhaust manifold+ceramic paint it for better scavenging, the 7000 rpm look interesting!

michael66899
03-05-2011, 08:50 PM
7K rpm is no problem for these motors, they don't see valve float until after 7500 ish. Granted there are guys with 1.8Ts running in the upper 7k range with stock heads which share most of the valvetrain components with the 2.8.

2001A6
03-05-2011, 09:07 PM
Well the sock rev limiter is 6800, and if you get the GIAC tune, its raised to 7100. People run 2.8 heads on GT 2.7s past 7k with out changing valvetrains. Just as he said. ^

I am un-familiar with the drop in power past 6000. Mine seems to pull pretty hard to the limiter, from ~4500-6800 is very strong.
The stock air box is pretty good, you wont see any power gains with an "intake" just get a drop in filter.
The heads flow plenty, only thing left is shitty exhaust maifolds. I havent seen any before/after graphs with stock/supersprint headers to see what they do to the curves, but iirc the gains are about 5hp.

Your best bet is a filter, cat back, and if you can afford it, the supercharger. Ive heard mixed reviews on chips, and the headers just insanely expensive. You could get some intake manifold spacers (VAST RS4-RS4) and they will net you some mid-range, but nothing crazy.

FNK
03-06-2011, 06:46 AM
The intake mod, would be slightly bigger tube in SS so the surface would be a lot smoother.
Also the exhaust manifold port polish would gain in CFM tremendously from the irregularities in the casting, Scientific Rabbit (http://www.scientificrabbit.com/node/27)

v3n0m
03-06-2011, 04:58 PM
You guys are crazy, when I drive normally, i dont shift past 3rpm, and when I drive fast/race I don't go past 5rpm (:
I don't think I ever redlined it

FNK
03-07-2011, 06:24 AM
Mine is an Auto, the Redline is automatic... even with a manual car, I would shift near the limit.

somebody5788
03-07-2011, 06:46 AM
I wish my supercharged one had a 7k rpm limit....

somebody5788
03-07-2011, 06:47 AM
You guys are crazy, when I drive normally, i dont shift past 3rpm, and when I drive fast/race I don't go past 5rpm (:
I don't think I ever redlined it

The stock rev limiter is a safe point, there's no reason not to.

I feel like FNK should just supercharge it and be done though. You're not gonna get more then 20hp IMO

FNK
03-07-2011, 09:55 AM
I never had a ride in a supercharged car, I guess the noise and power would be addictive!
But a 3500$ SC kit wont be for this year. I need to get this car in better shape!

v3n0m
03-07-2011, 09:24 PM
Yeah you might be right, but I think its red for a reason!