mottati

OK Gang, i just got back from getting my car dynoed again. Same shop as the first time since doing the supersprint headers with stock cats. (and powerchip/discovery automotive header software).All numbers are at the wheels on 91 octane california (oxygenated, in winter gas).

The Results: 353hp +20hp at peak (6600 rpm, according to my dyno graph), my peak torque (323) is only up by about 5lbs ft (at about 4600), but the real numbers lie outside of the peak hp numbers....

HP:from 4500 rpm on, the headers make more hp, about 15 at 5k, 22 at 6k, 28 at 7k and about 30hp at 7300 where my dyno ends.

Torque: again, from about 4500, more torque with the headers. +18 lbs ft at 5k, +25 lbs ft at 6k rpm and about +25 lbs ft at 7k.

Not too surprisingly, there is a bit of torque and hp lost at lower rpms. from 2-3k, i'm pretty much mirroring the stock hp/torque curve, maybe 1-4 units lower here and there. From 3-4k, there is some moderate torque loss, between 10-15 lbs ft, seems like the peak is about 15 lbs ft lost at 3600. Hp drops in that range too, about 10-12 hp lower with headers. This surprises me, as seat of the pants, the car feels stronger, so maybe powerchip plays with the throttle mapping to help hide this loss.

Out of curiosity, i pulled out my dinan catologue, to look at their hp torque graphs for their headers (and all the other stuff up to that stage). Not surprisingly, their 4-2-1 headers make a lot of torque, their graph shows 40+ more lbs ft torque (*their numbers are extrapolated to the crank) between 2-3k where my supersprints are about equal to stock. In the 3-4k range, where I have a pretty decent torque loss, dinan is making a claimed 17-21 more lbs ft torque at the crank. Makes sense, typically a 4-1 header will make more top end, a 4-2-1 more bottom end. From 4.5k+ rpm supersprints pull ahead. Even with the rest of the dinan stuff (their graph shows cai, mafs, exhaust and headers, and software) they make less torque than i got from the headers alone.

Clearly dinan had a good design for gaining low and midrange, at the expense of top end.
The next question, dinan claims 39hp and 30 lbs ft (at 7k rpm)for their throttle bodies! Wonder what that would do to my top end power!
Mike

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Mike

91 M5 Alpine White II, Silver Gray 3/90 production
17x8/17x9 M system with RS3's, Dinan 25mm front, 20mm rear touring roll bar; H&R/Bilsteins; Dinan Camber Plates; Confortti Chip, CD43; bmw/nardi blackline steering wheel, 3.8 Cam Gears

93 M5 3.8 Sterling Silver, Black 5/93 production (euro)

90 325iS, Black/Natur 5 speed, totally stock for now

93 Range Rover County LWB, Roman Bronze

09 335d Japanrot/Black, No I drive, Sport, H&R/Koni, Logic 7

me---> www.diablovalleyeyes.com
my parts source----> www.imbmparts.com

SC'dKellenersM5

mike...

good to hear that you finally got some numbers to validate everything....its so weird to hear a +40 change on the m5 from anything to me, as we both know that the usual changes is like +10 or so

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Im in the highspeed aluminum business

mottati

yeah, while the car does feel much stronger at the top end, i was surprised to see the big increase in the top end on the overlay graph from my last dyno run!
Mike

BKH

Really an outstanding outcome! I'm very impressed with your gains, but they also corroborate what I experienced after my header/Powerchip installation. After a suspension change headers IMO are THE mod.

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2009 Mercedes-Benz C63 AMG
2006 Z4 M Coupe
2000 E39 M5

Pete

Let me ask a question. Now that you have the car exhausting so much better, wouldn't you gain some of that lost lower end torque back if you did something now to help the car breath better? Seems to make sence to me.

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2000 M5..."The Precious"...yup, the wife named it......Democracy is two wolves and a lamb voting on what's for dinner. LIBERTY is an armed lamb contesting the vote.

Sean@D/A

Hi Mike

Thank you so much for the opportunity to work with you on this project. As we shared in the beginning the feel of your car was going to be night and day with the addition of the Supersprint package and Shadowmans custom software.

I’m glad you were able to get some numbers your happy with.

Have a good holiday

Sean

mottati

That would make sense, but other than throttle bodies and maybe bigger mafs (dinan's the only vendor of both of those that I know of) i don't know what else to do. (and i am seriously considering that route, after i save up some more pennies).
Mike

gsfent

Doesn't Dinan just drill out the TB's? Seems like something Shadowman could do without the Dinan $$$. The secret is in knowing where and how much. If there was a used set floating around from D/A takeoffs, maybe we could get this done by Bill and send back the originals as a core exchange after the installation like we do with diff exchanges. Bill, are you listening?
Regards,
Jerry

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'01 Black/caramel
Dinan Stage 3 suspension, SS jet coated headers, ESS SC kit w/ 1 range colder NGK's, 92mm pulley, 440 Big Greens, Evolve MAFless tune, RK plenum plates, CNS 10.5 dual mass clutch, open brake ducts, Hamann front splitters, TEC cupholder, U.S.(Euro style) tilt/slide armrest, 6k HID fogs, 6k super white low beams, V1/Stealth1, dual head LI, 2.65 diff w/40% lockup/2x dynamic, compact spare, Euro trailer hitch, Mocal oil cooler, ACS type rear spoiler, Rogue custom SSK and tranny mounts, ST 355 BBK (fronts), BP sway bar brackets, Bluetooth retrofit, Speedhut boost gauge, Dinan TB's and VS, KB BAP, Howerton/HFS-3 Aquamist WI trunk setup.......

mottati

You're right Jerry.... Lets start a line! I think keith97m3turbo (or something like that) had a spare set that he was going to bore out. I'm sure they could make some larger mafs too, maybe out of carbon fiber.....
mike

gsfent

Mike
I remember reading somewhere that the MAFS were prob good for closer to 500 hp, and they were not the bottleneck. In any event, it sounds like something that D/A guys would know and be able to handle. Line forms to the left.............
Regards,
Jerry