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Discussion Starter #1
Throughout the course fo thinking right now, I finally have a response to the comments left to others about raising a redline on a motor with stock internals.

It comes to my attention that most people say "Your engine does not make more power above the stock redline, so your doing nothing by raising it but possibly causing damage to the internals" and other such things when you tell them you want a higher redline, or you are running one. I have a good response and I want feedback =)

I have found that my current motor loves the increase (from 7400-8400RPM's) and with a slight cam timing change, the car really pulls through the higher RPM range. I have noticed better speed increases and performance by doing this. When people come out with their typical response... they forget: The motor most likely (in my case does) has a very free-flowing exhaust and intake to go along with the RPM and cam changes. It is theoretically possible to get more power in a sense if not in the actual sense of HP.

When I shift out of a high RPM (8K+) into the next gear, I am now left more into my powerband (which is thus risen by the timing change as well) , and accelerate through more of a steady and costant powerband then when it is normal. When I upshift, I am now left at around 5-5.5K RPM's.... really a sweet spot for my motor.

I do know this because before my adjustment, on a slight rolling start I am now able to stay side by side with my friend's audi.... when before he would slowly creep past me.... very slow creep. I have now since been able to creep past him.... big difference in my eyes, as I am trying to get my D15B to be able to be equal (not off the line, cause he's AWD... thats almost impossible at this point) or slightly greater while still being N/A before I switch to a turbo setup. Most of the runs against this audi started with a slow roll side by side up to 15 and 20 MPH where we would both punch it on a honk of the horn. [Car info: 01 Audi A4 Quattor 1.8T, mods:none but lowering springs/bilstein shocks]


Ok, gimme some feedback on this.... cause I know u got it in ya =Þ

Ill try to get some audio/video of the sounds this beast is making now!
 

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well on my old setup i droped .3(in the quarter) by raising the redline but it was camed. The power kinda died after 7k but it was still faster when i took it to 8k because it put the next gear back in the powerband like you said. That and it wasnt hitting stutterbox before crossing the line.

your motor must be a z6 or at least vtec.
 

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Retarding my cam timing 2.5 degrees raised the power band and allowed me to rev to 7200rpm with power. The drop during gear changes now as you said helps the next gears pull. D16A6 rev limit is 7000rpm? I dunno but I reved well past this and the engin eloves it, if it breaks then i get a new engine, pretty cheap now. Around US$100 for a good motor (Hong Kong).
 

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I would... but I flat out just never put the car into redline. I make it to around 6700 and then shift if I'm racing. It's my only car, don't need it blowing up on me, and I don't find it reasonable to be taking the car to 8000rpms on the street anyway.
 

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Discussion Starter #6
My stock JDM redline is 7400, but higher is easy/ok because the short stroke of my motor works well with it =)

I need to get on a dyno to fine tune my shiftpoint, reset my redline, and adjust the tard for the sweet spot... it aint quite there... once I was able to feel it.. but I need to get a dyno =/

The Ostrich is workin great though, and everytime me and my friend are drivin, people always watch me go by... damned loud =P Audio to come soon... I just found out tonight my camcorder fits perfect into the gap between my headrest and the seat =P Built-in!

But my main stay with this is: I am getting more power out of the plain and simple fact:

My powerband drop-off when revving 1K above my stock red (7400), is nothing compared to the difference of my powerband when shifting out of gear into the next... being higher in a more constant/steady powerband is better than being behind the powerband I'd say!
 

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I think people dont like to over rev because of Valve Float. Valve float happens when the valvtrain inertia is too great for the valvesping to overcome. When this happens, the lifter no longer exactly follows the cam profile. Thus, the valve does not close when it supposed to, or "floats". The downside of this is that if you have raised compression or larger valves they may now interfere with the pistons, and cause bad things to happen. Another problem is that when the lifter leaves the cam, it wil "slap" back down, possibly galling the cam or the lifter.

To cure this you need stiffer springs, but not to stiff.
 
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