karth

To some extent, I see what you're saying. One pound of unsprung weight is equal to 8 pounds of sprung weight or something like that. Dinan says almost 30 hp gain from the stage 3. I had about 16% driveline loss before based on the BMW quoted 325 crank hp on a 545i. So assuming the 354 crank hp for Dinan's stage 3 is accurate, 84% of that is 297.3. So 18hp gain at the wheels. Let's assume the R10s are 10 pounds heavier than my stock wheels and tires each, which I seriously question, as my stock wheels/tires are plenty heavy (I might break out a scale and the wrenches this weekend to find out for certain ). So the equivalent of 160 pounds of sprung weight. That's still not going to make you lose 27hp on a chassis dyno.

I owned a 2006 Evo 9 prior to my BMW, and did some mods to it. Each time I did a predyno at this facility, the hp number was within 3-4 hp of the number the last time I was in there, so obviously there's some fluctuation for conditions, etc. Not 27hp loss though, especially with the same ambient temp and humidity within 2% of the prior runs. Plus no matter how you slice it an AFR of 10:1 on a naturally aspirated car at WOT is rich as piss. Hell, on a turbo car that's running rich.

I'm not disputing that throttle response is improved from stock, and that the exhaust is louder. However, assuming the answer back is, everything is as it should be, are those two factors worth $3000 in parts, plus labor for less horsepower? The answer is obviously no. Not even no, but more like &!#@ NO! However, my dealer is committed to taking a look at the car and sorting it out if there's something to be found. If they say everything is fine and/or Dinan isn't forthcoming with assistance, you can bet I'll be sure to trumpet to the winds about my experience. I did plenty of searching on the web last night and didn't find any other pre and post dyno numbers for a 545 Dinan stage 3 except those from Dinan themselves. Maybe in the three weeks and change since my Dinan install something like an o2 sensor started having problems on my car. I'm not accusing anyone of anything yet, but for the cost involved I think some investigation is in order at least.

/rant off until my dealer appointment

heezy545i

I'd be upset too if the numbers weren't to my liking. I'm not familiar with the dinan software, but expecting 27rwhp from an intake, exhaust and throttle body is really asking a lot, especially on a NA car. I'd expect some improvement, but no where near 30rwhp.

It's difficult and may be wrong to compare the dinan software from one car to the next, but the dinan software for the e46 M3 did little more than increase the rev limit. Almost no extra power was found with the software on that car.

The dinan claims are just that, claims and I wouldn't expect to reach those numbers. Not sure what dinan or the dealer can do to appease you, but good luck.

karth

I wasn't expecting 27rwhp. I'm guessing their quoted numbers are crank hp. I figured that Dinan would be less likely to exaggerate since their stage one tune only promises 8hp, as opposed to guys like Powerchips who claim like 20 cramk hp from nothing but a flash. Looking the predyno, with the AFR at 13.5:1, I don't think BMW left a lot of power on the table from the factory. The European 545i was listed at 333hp I think ,which is 8 more than the Us model, which BMW probably did to account for some of the piss gas we get in parts of the US. I'd have been happy with 10rwhp, when you include the better throttle response and sound of the exhaust. However, -7hp is pretty much unacceptable, especially with a 10:1 AFR. When you're running a car that rich you're not going to get proper combustion inside the cylinder consistently.

I just think that the only way we can get any brand's aftermarket manufacturers to deliver what they claim is to test and call them on claims that aren't true. I'll be sure to share whatever the outcome is once I have information. Thanks for the replies!

vegastrashed

You're not alone with being disappointed with Dinan. Folks over on M5board aren't too happy as well.

JetBlack

Ok just like I told the guys in the other board Dinan uses a HUGE dyno fan(size of a mini cooper) and sees different A/F ratios than you do and will ALWAYS show that a car makes more horsepower at their facility then the one you went to.

Please read the white paper on their website. www.dinancars.com or call Eric Bateman at 408-779-8584 x105

karth

Apparently Kelleners is having a problem with their tuned cars losing power with PROGMAN 25 installed. They've been reverting cars back to version 24 and reflashing. I wonder if this is the same issue. I'll call the suggested number though and ask.

sirch

I guess I'm going to get the powerchip.

rpav

This is BS! Where is there a dyno here in SoCal? I wanna dyno my biatch and see wtf kinda hp i have now. Good writeup!!!

karth

Update: After several days going back and forth with Dinan through my dealer, sending dyno sheets and asking, do you flash a 10:1 AFR, etc, and getting back, here's Steve's white paper on dynotuning so any dyno run not done here is meaningless, then me saying, even if I'm not getting good airflow through the radiator because I don't have your magical happy super fan my first run wouldn't be heatsoaked so my AFR shouldn't be 10:1 since I wouldn't have knock on the first pull when it's 77 degrees in the shop (plus I've been in plenty of dynotuned Evos that are at 11.5:1 or so on a dyno and a wide band at WOT at 80mph shows nearly the same AFR as stationary on a dyno, there is not this magical leaf blower straight into your engine hoodscoop on most cars), getting ignore the rich AFR man behind the curtain lalalalala type stuff back, and the, no other 545 or 550 owner has ever complained ever never ever, etc etc, even after providing forum posts from m5boards and other places showing rich AFR and loss of power from PROGMAN 25+ reported by Kelleners and other tuners, my dealer is going to put my car back to a pre-v25 PROGMAN and reDinan flash me, and I will dyno again. I'm gonna monitor the knock sensor this time too. And if my AFRs are magically all better I'm gonna chew someone's ass out at Dinan. Argh. /rant off

Do I sound like a satisfied customer yet?

vegastrashed

You should read this experience of a M5 owner who had the Dinan software.