blackbenzz

Went to a shop today where a tuner was tuning a few benzes. It was a nice AWD mustang dyno with a reallyyy nice fan supposedly able to simulate up to 80mph driving conditions. First car gets on (Renntech SL63) and gets tuned and makes about 370ish whp. I'm thinking wow this dyno reads really low. Next an E55 with MBH longtubes and 180mm pulley makes about 430whp and 620wtq. Hp looks lower than usual (consistent with low SL numbers) but the torque really caught my eye! I did one of these So bth customers go for a spin in their cars and are very happy with the new power. Then this other benz gets on the dyno and makes 683whp and 774wtq! I am in shock at this point. All I keep murmuring is "impossible, that cant be, no way". Keep in mind this car had no nitrous, no icing down, and 93 octane. The dyno operator says he wants to see how much torque the car makes down low since peak torque is made at low rpms in these cars and then falls off as rpm goes up. Ok, so we sit 2 guys in the trunk and strap the car down real tight. Starting from a very low mph the dyno operator starts the pull. The car starts spinning tires on the dyno with 2 people sitting in the trunk I keep repeating what I was saying before. Pull up the graph and look at it... 939wtq before it spun the tires (clearly visible on graph, there's a big dip in hp and trq). I guess this is the smiley to use now I personally am not a big believer in dynos. The dyno operator was also in shock. He said the mustang dyno comes with a diff strap that's used for race cars and if the car comes back later we can try it for free. The owner says ok and agrees to bring it back another day. Take it out for a spin and the thing spins tires HARDDDD at 50mph and just keeps spinning em until you let off the throttle. Hmmm. At that point I say the only way I believe that number is if I see a 1/4 mile pass. So we slapped some drag radials on it and rushed to the closest redneck track. Get there and noone is at the gate. Sit there for 5 minutes, nothing. Ok, we head over to tech, noone there. This place is PACKED but noone at the gate or tech So I ask one of the people that work at the track and they say test n tune was cancelled for the night becaus ethere were too many cars actually racing. Checked the DA and it was near zero

Soooo.... Do you guys believe in dynos? I sure as hell dont. Show me a 1/4 timeslip and you make me a believer. 1/4 numbers to come in the following weeks.

sneakyneon

Is this benz a 55K platform? Any further info on mods...

blackbenzz

Yes it has a supercharged 55 motor. Basically all the bolt ons and cams. Stock bottom end, stock heads (with exception of the cams).

mthis

aftermarker blower?

sneakyneon

Did it appear to be a stock SC?
We all have seen track times for full bolt-on cars (10.7 to 11.2) any dyno # can swing wildly. I'd Love to know if something new has come to the MB world!

MBH motorsports

180mm pulley, headers, and a tune making 430whp? and 620twq? somethings up for sure. Seems like an inertia setting wasn't right.

sneakyneon

I think paying attention to wording is important here.

mthis

blackbenzz

I agree with you guys, something isn't right. Which is why I want to see 1/4 numbers. But, why such a discrepancy between the hp on the cars if the settings were the same for all three cars?

Again, I put no stock in dyno numbers. Just want to see what others think and play devils advocate

Thericker

Thank you! I've seen these type of extreme low HP & Super high TQ #'s on every Load bearing dyno made. IE wrong curb weight entered or incorrect gear ratio, or ESPECIALLY being tooo tightly strapped/weighted etc can set these DD/MD dyno's to looonsville mode..

Can't believe you even slightly believe this Ahmad?

An Inertia based Dyno is a DynoJet... A Load-bearing dyno is Mustang or DynoDynamics as Ahmad describes in OP..

blackbenzz

Is 683whp extreme low hp to you? I saw them enter the correct curb weight. How does strapping a car down tight effect the numbers? Since I dont care much about dynos I never really paid much attention to the factors that go into the numbers

I don't believe it... did you read what I posted?

Thericker

Are you serious? You just posted they loaded the trunk w/two extra people & strapped it down extra tight, Load bearing dynos are heavily skewed by the LOAD placed on them.

Did the Dyno operator weigh the 2 extra dudes in trunk or calculate the extra force/LOAD applied by extra tightening of strap's? Just saying, those are your main reasons for unblievable 55k making said CRAZY HP & 939wtq OFF Nitrous...

Beyond LIGHTLY MODDED 55k making ridiculous 620 rwtqYou of ALL people should know this like A-B-C's Don't get bent I'm just relaying what I've pain-stakingly learned thru the years studying dyno's here & around the web/in person etc...

blackbenzz

First pull was done normally. People were added to the trunk and straps were ratcheted tighter for the pull afterwards where it spun tires.

Why are you trying to argue with me? I've said time and time again dyno numbers dont matter, 1/4 mile does. I think I've gone out and ran my slips numerous times. Ive never posted any dyno graphs. You must have missed the whole going to 1/4 mile part. Speaking of which, when are we ever getting any times out of your car?

Thericker

I'm NOT trying to argue w/you, you asked/posted I merely was answering your questions on Dynos... No 1/4 miles as you know, she's a dyno queen/street racer

Re-read what I posted earlier, wasn't trying to argue, you asked for answers I gave mine.. It's all good guy

bassn_07

Dyno's are great for using as a tool but only if it could be properly strapped down. Unfortunately at times this is a problem, ask Sneakyneon and Mo about our cars at the last dyno session....

I'm with you brotha, slips over dyno sheets anyday. As for people believing slips, not always..... I've posted dyno sheets, track slips, more dyno sheets, and slips from various tracks. People still called bs....

Either way let's see what kind of numbers a benz like that would produce.

c32AMG-DTM

What's with all of the "cloak-and-dagger" coming out of MBW these days? At least this thread didn't use the term "hypothetical" yet...

blackbenzz

The whole point of this thread was to show everybody that dynos dont mean much and comparing dynos is not smart. I see it happen all the time, compare one cars peak numbers with anothers. I'm sure one of the settings was off or something in the dyno. Again, I dont believe the numbers.

skratch77

We hit the dyno with my brothers car and his car downshifted from 3rd to 2nd and the torque was in the 600+ for a stock e55,his car was not dynod in the right gear or he sprayed a 200 shot for a quick second.

at 600rwt the car would make over 400whp just from the amount of torque it was making,the ratios and gearing were not right.Here is the dyno from second gear.

Yacht Master

[QUOTE=skratch77;4257447] car downshifted from 3rd to 2nd and the torque was in the 600+ for a stock e55,his car was not dynod in the right gear QUOTE]

+1

Anybody that uses humans to ballast a car on a dyno is a tard.
That said, I would not trust a tard to accurately dyno anything.

KLR CLS

Dyno's should be used as a tool for comparative difference of modifications of the same car, not as an ultimate compartive tool for the power output of two different cars on two different dyno's.

For what it's worth, the same is also true of comparing 1/4 mile times of different tracks. So many variables like elevation, track incline/decline,prevailing winds, Latitude, timing equipmentor calibration, surface prep, never mind driver skill or car variables.

Bottom line is mod your car, enjoy it, repeat...

Benz-O-Rama

Who was the tuner?

bassn_07

Agreed! Nicely said.

This is a great example of why we just can't compare our cars performance from around different parts of the country, let alone the world. I had a conversation with a track official at Sacramento about their traps, they said it was good enough for NHRA..... Can't really argue with that. My point is that NHRA understands that not every track is created equal and some variance is allowed to a certain percentage.

I honestly believe BB's thread is about how useless peak dyno numbers are and should be taken like a grain of salt.

blackbenzz

These guys should consult some of you all to find out how to really dyno a car

http://www.youtube.com/watch?v=N_K4J...eature=related

http://www.youtube.com/watch?v=I2PcF9_vLfs

http://www.youtube.com/watch?v=I95tS...eature=related

http://www.youtube.com/watch?v=DV6siknODUg

http://www.youtube.com/watch?v=UjDGY95nmeg

http://www.youtube.com/watch?v=elSm5...eature=related

skratch77

I just showed you a dyno that was set up to run 3rd gear on a e55,we put in the numbers and drove the car to 3000 rpms and held it there to set the dyno up and looked what happened when it ran in second gear lol

in 3rd the car put down 450ftlb 390whp in second it put down 627ftlb!!!

Karlson

Ahmad, I just can't stop laughing! seriously, 683whp and 774wtq is REAL, I saw that with my own eyes, so I don't know why you blame it on a dyno. That SL got all Renntech goodies and still had low numbers, so if it were all three cars had crazy numbers than I would believe that dyno is wrong. 2nd car was mine and 608ftlb is a lot, and I am sure it was a little off, but still. Sl63 had low numbers, mine was about okay, but "this other benz" guy had the monster car, so I don't know why are you complaining!