[dzenno]

Originally Posted by enrita

I dynoed exactly the same as you on stock boost fully bolt on (stock turbos) and 251 completely stock.

dynojet STD numbers? if yes that sounds encouraging...do you have that graph to share?

[enrita]

[dzenno]

Thanks, wish that was a dynojet though..those whp/wtq curves the way they're plotted don't intersect at 5200-5500 rpm..really hard to compare..

EDIT: oh I see it's in NM not ft/lbs..

[jpsimon]

dzenno.. you're looking far too much in to the dyno numbers. does the car feel good/drive well? it obviously is performing well if you did 121mph. Dyno to dyno there can be (and is) huge differences. If it makes you feel any better, there is a dynojet by me that reads as low as that. Stock 335xi made 245..250whp there

[Irishace]

Originally Posted by dzenno

Last time (July 1st) it was pump 94 + 100% meth...when I went alone and did the 121mph I had MS103 and 100% meth as far as I remember...last time (july 1st) my shifting sucked as I was concentrating too much on my launch with those damn DRs

Really what I'm after here is why on the stock tune/boost (map0 for jb3, valet mode on procede) i put down only 272whp/286wtq with full boltons catless DPs/exhaust...This would mean that without them I'd be at 245-250whp stock which is approx 25-30whp lower than avg...

what did you dyno stock with your boltons at Champion Motors (map0)? have that chart to share?

EDIT: I actually ran 80/20 meth mix with MS103 when I ran that 121mph...just checked my old post for details...

I dyno 286 at the wheels with bolts ons and map 0. Graph below:

[dzenno]

jpsimon, if you look at this dyno plot from Irishace, its the EXACT SAME dyno I go to for my runs...i know ALL about different dynos, different days, different numbers but THIS is not the case...this is SAME dyno, similar boltons, almost same weather conditions (~20Celsius)...

The car used to put down 393whp/420wtq on 94 pump (temps in 30s (90-100F)), although 2 years ago...if you've followed some of my threads in the last 2-3 months, I've been down to 340whp because of bad injectors/plugs/fmic boost leak that are all now addressed but even with all that addressed I managed to get the car back to 365-370whp on pump 94...i'm still after at least 15-20whp on these SAME dynos (2 dynos I used all this time where I've done a LOT of pulls , all kinds of conditions)...

I'll do a pressure test on my induction system and see if there are any leaks (nothing obvious in the logs) redyno on pump 94 after that and on MS109 and meth after that...

my current crazy theory is that there are no boost leaks BUT it might be that carbon buildup on the exhaust valves has collected enough to cause compression issues and cause a 15-20whp loss...this isn't something you can feel butt dyno or miss in your day-to-day performance....just f*ckin weird that its happened and I still have no explanation for it...

[jpsimon]

gotcha!

[gian335]

dzenno, sometimes dyno's dont tell the ultimate truth, trust me. If your traps are up there and your car is running strong, then there is no need to worry. I dyno 375/380 on pump 94, no meth at all and I have dyno'd at other dynojets and they all seem to make the same power for me( within 6whp).

I went back to champion with meth and dyno'd 387/417 on 75/25 meth,water. That day my meth was not working properly and I had some flow issues, which was very dissapointing for me, only picking up 12 whp. But I knew that it wasnt switching to map2 which was 17 psi for long, litterally for maybe a second during the run. This is all at champion and STD corrected. What I really wanted was to see how my car drove at the 1/4 mile. With some ms109 and meth (17.5-18psi) And I was able to trap 118 and 119 consistently with my setup, which was a good feeling. And honestly I feel as if theres no point in going back to dyno after, because I know my cars potential. Trust me its all about how your car drives . U got a beast and Im sure that our cars have never been faster then they are now.

[BrianMN]

Doesn't dzenno's TQ seem to drop off fairly early, and fall fast? That really can't be a normal torque curve...

[dzenno]

Originally Posted by BrianMN

Doesn't dzenno's TQ seem to drop off fairly early, and fall fast? That really can't be a normal torque curve...

I know the car's running stronger now than ever but this is true only on meth...on pump gas 94 my car used to make 393whp/ and this is what I'm after and trying to understand..where did this mysteriously disappear, 20whp isn't really negligible, that'd be in boost terms a whole 1psi of boost say, not to say it IS boost..

Don't get me wrong, I'm really happy being able to pull 121mph traps now BUT at the same time there are definitely things to be looked at..Had I not made those 393whp numbers before I wouldn't be left wondering as I am today..

I'll follow those basic tests and redyno on pump to see if any changes..then I'll repeat with the right meth mix and MS109 to see peak..

Torque spike at 4400rpm is another thing that's a mystery at this point..

[enrita]

dzenno, just FYI my exhaust valves had a lot of play after 65.000 km and pretty dirty as well. This lead to head renovation. Now i dont know if this was due to the problem i had with the upgraded turbos and the burned cyl 2 piston (my shop says it has nothing to do with it) but since there are not many people around that had to lift the head after so many km its worth knowing this.

[blubyu]

Originally Posted by dzenno

Thanks, wish that was a dynojet though..those whp/wtq curves the way they're plotted don't intersect at 5200-5500 rpm..really hard to compare..

EDIT: oh I see it's in NM not ft/lbs..

I have seen you mention a few times that dynos are intersecting at different rpm ranges. A proper calibrated dyno will intersect at 5252 100% of the time if the torque and horsepower are scaled the same on both sides.

[Former_Boosted_IS]

Originally Posted by dzenno

Ok, point taken. What about the VANOS torque spike? When I tried the JB3 2.0 they richen up AFRs a bit there and reduce boost on purpose to eliminate it. Does proceed do anything similar, any advantage doing this?

In any case, I'll do a prep on the points you raised above and re-dyno soon..

dzenno, the JB3 doesn't richen things up there to remove the spike. As I have tested, the VANOS event is accompanied by a change in boost. That change in boost can cause an AFR change since the AFR is boost related.

[dzenno]

Originally Posted by blubyu

I have seen you mention a few times that dynos are intersecting at different rpm ranges. A proper calibrated dyno will intersect at 5252 100% of the time if the torque and horsepower are scaled the same on both sides.

No, you're absolutely right...I was thrown off by different scales on some charts..some of them have 500rpm increments down the bottom, some of them 1000rpm...

All charts I'm looking at now, including mine, have the whp/wtq (where wtq is expressed in lb/ft) curves intersecting at 5252rpm...sorry for the confusion..

[dzenno]

Originally Posted by Former_Boosted_IS

dzenno, the JB3 doesn't richen things up there to remove the spike. As I have tested, the VANOS event is accompanied by a change in boost. That change in boost can cause an AFR change since the AFR is boost related.

Ok, didn't know that. I made my conclusion by looking at AFR and boost curves on the JB3 logs and this is what it looked like. However, JB3 is for sure lowering boost at this transition to smooth out the curve and balance out the VANOS-shift-induced boost spike, right? On the procede Shiv says they retard timing a bit at that point to minimize the spike...that's all cool but doesn't seem to help on my car when I ran the JB3...with procede the spike in whp is eliminated there on the meth map (higher boost) but its still there on the wtq curve..on the pump gas map however, both whp and torque curves still exhibit it..

This isn't my main concern though, just something I noticed still occurring on my car with latest tune firmware (both jb3 and procede) while I'm no longer seeing it as much with these same tunes on other cars as tunes seem to be addressing it (their own ways)...

[Ilma]

Originally Posted by enrita

dzenno, just FYI my exhaust valves had a lot of play after 65.000 km and pretty dirty as well. This lead to head renovation. Now i dont know if this was due to the problem i had with the upgraded turbos and the burned cyl 2 piston (my shop says it has nothing to do with it) but since there are not many people around that had to lift the head after so many km its worth knowing this.

That's an interesting point.

I believe when Dzenno was told by the dealer he had a blown head gasket (which he did not), they did a cylinder pressure test and found he had some leakage.

Maybe worn valves create such results?

Just throwing that thought out there.

[dzenno]

Ilma, those results, even though nonsensical at the time, have left me wondering as to what the outcome really would've been if they didn't fabricate the results..

I'll have the compression and leak down tests done as well at a rep shop just to get those dealt with properly..

[shifterboy45]

Originally Posted by dzenno

Ilma, those results, even though nonsensical at the time, have left me wondering as to what the outcome really would've been if they didn't fabricate the results..

I'll have the compression and leak down tests done as well at a rep shop just to get those dealt with properly..

i wouldnt give credence to any of the results or conclusion inferred by the shop who performed the diagnosis of a bad head gasket. they did not follow the traditional methods of problem elimination, therefore any talk of valve leakage can be tossed as other ploy to get the work performed.

i remember that whole incident and it was pitiful to say the least...

so you have an understanding of the two different test --

1) a compression test is taken usually to qualify a low spark line in ignition -- like a cylinder balance test except the engine plugs are removed, the engine is cranked over, and the individual reading are compared with engine specs; such as 180 - 200psi - a 10 to 12% variation/margin is acceptable per cylinder -- a cylinder that is unusually low, and the spark line (on your occilliscope) is short (not the proper height based on rated ignition system output) could be consider low or a dead cylinder. on the other hand if the car has a bad detonation problem, and the cylinder compression reads well above rated numbers -- could possibly have serious carbon deposit problem decreasing the CC volume, raising the compression.

2) a leak down test is used to qualify if there is a cylinder sealing problem,
rings or valve. this test requires that all the plugs be remove and each cylinder is brought to true TDC (for that cylinder) since the engine works on a "720 degree principle" -- takes two revolutions to complete one combustion cycle -- so making sure the valves are closed on the compression cycle is mandatory - since there is also a time when the valves closed, just momentarily, during the pre-exhaust phase -- the cylinder is then pressurized with an compressed air supply.. this will reveal if there is excessive leakage past the rings or the valves. --- this is measured on the value of percent of loss over a specific time. it will also reveal audibly if there is a valve/ring seating problem. you can hear the air discharge through the intake manifold if the valves are not seating/ or through the oil filler cap area if the rings are leaking --

thats just a quick explanation -- both test are a little more detailed - it gives you an idea what the shop is supposed to be doing --

[dzenno]

Great info shifterboy45, appreciate it..

I'm thinking of trying this on my own as well to see if I can pull it off...I'm pretty comfortable with it except I don't know how I'd crank the engine over when the plugs/coils are out..I'll still have a shop do it as well though to make sure it's done right..

EDIT: anyone have a pic where the crank nut is located and the best way to crank the engine over to set the piston at TDC.

[Former_Boosted_IS]

Originally Posted by dzenno

Ok, didn't know that. I made my conclusion by looking at AFR and boost curves on the JB3 logs and this is what it looked like. However, JB3 is for sure lowering boost at this transition to smooth out the curve and balance out the VANOS-shift-induced boost spike, right? On the procede Shiv says they retard timing a bit at that point to minimize the spike...that's all cool but doesn't seem to help on my car when I ran the JB3...with procede the spike in whp is eliminated there on the meth map (higher boost) but its still there on the wtq curve..on the pump gas map however, both whp and torque curves still exhibit it..

This isn't my main concern though, just something I noticed still occurring on my car with latest tune firmware (both jb3 and procede) while I'm no longer seeing it as much with these same tunes on other cars as tunes seem to be addressing it (their own ways)...

I will go through some logs to look at the boost in that rpm to see. I will report back. I was more concerned about AFRs there because of nitrous, so that is why I have studied the VANOS event quite a bit.

[R1000K3]

Originally Posted by enrita

dzenno, just FYI my exhaust valves had a lot of play after 65.000 km and pretty dirty as well. This lead to head renovation. Now i dont know if this was due to the problem i had with the upgraded turbos and the burned cyl 2 piston (my shop says it has nothing to do with it) but since there are not many people around that had to lift the head after so many km its worth knowing this.

Interesting, but real bad news if the valve guides normally wear as fast as on some other engines with major design flaws in the valve area. High loads and RPM's will contribute to the wear but 65.000 km's on a modern car should not cause any issues like this. The lubrication of valve steams is always difficult so a low viscosity oil should be better in this respect.

[shifterboy45]

Originally Posted by dzenno

Great info shifterboy45, appreciate it..

I'm thinking of trying this on my own as well to see if I can pull it off...I'm pretty comfortable with it except I don't know how I'd crank the engine over when the plugs/coils are out..I'll still have a shop do it as well though to make sure it's done right..

EDIT: anyone have a pic where the crank nut is located and the best way to crank the engine over to set the piston at TDC.

sorry for late response...

if youre gonna do a compression test be sure to render the ignition system harmless.. get a remote starter to crank the engine over. youll have to jump the hot lead (+) and ignition lead terminal on the starter.. of just have someone in the car and crank it over for you. plus it cheaper... pull all the plugs and test in cylinder order 1-6 and note you readings.

as for the leak down test -- is best if you have a shop do it for you, and watch them if they alllow you in the shop.. and absorb the knowledge.. sometimes books dont give you the little nuances that make working on cars fun..