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Discussion Starter · #1 ·
So, my car went on the dyno and came back at 367bhp. Or 312 whp, I'm worried as its a little low, had a compression done and it came back reasonably okay, ranged from 175psi to 200 psi, one cylinder was 160psi, just wondering what other S62s have put down on a dyno? Car is on 170k
 

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Sounds reasonable to me. 170k, you lost a few ponies.
 

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Vanos is the number 1 culprit for down on power. Mafs can cheat you a few hp too. Little air leaks a few more.
You just posted the punch line as I type this, but I was going to ask have your CPS been replaced and have you done the VANOs board maintenance?
 

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Discussion Starter · #5 ·
So I quoted on the post at the time if the dyno the vanos was orignal. I've literally just picked the car up form having it done, and cps were done about 8 years ago
 

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Discussion Starter · #7 ·
Sorry I've explained it bad. So a few months ago I had the dyno and everything was original. I literally have the vanos work done this week. That's the confusing part. But at the time of the dyno it was original. I had TCG all vanos seals. And units rebuilt
 

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Get it dyno'd again. No sense worrying about a dyno test when your vanos needed maintenance. Beside those results are near average for an average car. If the car was on a super maintenance program you might expect more but lots of little stuff steals a few HP here and there.
 

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Discussion Starter · #11 ·
Thankyou, so does warn vanos cause a power loss? Now the repaires have been done the car dosent feel any faster but now does feel more responsive and sharper
 

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so does warn vanos cause a power loss?
Wear is not the issue, slow responding and lack of accuracy of the hydro system is the issue. The timing of when the valves open and close is very important. In short the vanos returns exhaust gas to the intake side to reduce NO2 emissions. I does this by closing the exhaust valve early and lets that trapped exhaust gas, be compressed, this consumes power. It then holds opening the intake valve until that compressed gas returns that power on the other side of TDC. That balance is critical because of the power consumption. Vanos really is only active for the most part between 1000 and 3000 rpm, by 3000 rpm the car wants the cylinders full of air so it can add max gas. Those are the simple terms it is more complex than that but I am not going to type for 2 hours to explain it all.
I have explained it several times but can't point you to a specific post, but if you are reading old posts from time to time you will likely come across a more detailed explanation.
The short answer is you will see this on a dyno but not in your butt. You will not feel 25 hp in your butt unless you know it is there and still that is just your brain not your butt. Lots of people have complained they are down on power after X amount of work only to find the dyno says they are producing more now than before. You get used to things.
The fact that you have noticed sharper and more responsive is a very positive thing and likely means you are producing more power.
A friend of mine made a 100hp find in his car but it is 1800 hp engine. It took 2 tenths of his 1/8 mile time, he says he feels it but I doubt it, it is so small. I change my Audi from 12psi boost for daily duty to 20 psi for dragging and I feel that but that adds likely 1/3 to 1/2 the HP again. Just a guess never had the car on a dyno so those numbers are best guess from math.
 

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Thankyou, so does warn vanos cause a power loss? Now the repaires have been done the car dosent feel any faster but now does feel more responsive and sharper
Wouldn't it make sense to put it back on the (same) dyno and share results? That way you can address what, if any, power changes exist. By using the same dyno, you limit the variables.

Regards,
Jerry
 

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Find a healthy e39 m5 and race with it from 50 or 60 miles .. till end of 4th gear ..if you both stay nick to nick ..that is mean your car making good power ..even if your car behind by half a car .,still your car in a good shape ..

Thanks.
 
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