Carl Byck

Has anyone Dynoed 450rwhp or more on a street port using gasoline? If so could we see a dyno sheet, and what your basic set up was? I've seen claims from time to time, but I have never seen an SAE dyno graph. I would be especially interested in a GT3540, GT40, T66, or a hybrid in that size range. I have seen some T51s in that range, but that turbo is a little large for my application. Thanks in advance, Carl

BDC

Not yet but I plan on it. I'm still 25rwhp shy of it.

B

vosko

iTrader: (4)

15psi T78 tuned very rich (10.0 AFR on wideband), street ported engine

Carl Byck

Thanks Vosco, what do you figure the correction would be on that given the temps in NJ? Anyway great job. Can you give me an idea of rpm across the chart? Is this with your current set up(T78)? Thanks, I know you guys are sick of me being cynical about most of the big HP claims, but I'm ready to buy a turbo to replace my TO4. It looks like your just starting to really crank at 90mph, must be a handful. Anyway I appreciate any one taking the time to post. Brian, are you running a 60-1?

Carl Byck

Sorry, missed the note on your set up at the top.

Marshall

Vosko, do you know where those spikes at the end came from (they also correspond to your 459 peak)? Kinda looks like a fluke while the dyno was spinning down.

AJC13B

Vosko - 10.0?! So the hole in the ozone layer is your fault!

RICE RACING

rxrotary2_7

yeah what is that?

es

That doesn't look like a very clean sheet to me. Good #’s, but lots of Squiggle at 5252 which could mean approaching detonation or ignition problems. The spike to 459 at 125 MPH points me to ignition breakup since it's so high in the RPM band.

5252 (Torque & HP cross) appears to occur at 87 MPH. Which would mean this was a 4th gear pull on a car with a 4.33 diff ratio, & close to stock circumference tires. That would mean your top end breakup started at 7400 RPM. A big port + T78 combo shouldn't drop off in power as your dynos did. This reinforces the ignition breakup hypothesis of mine.

Maybe you should have leaned it out to 10.5:1 or 11 with a safe ignition map to see if the squiggles cleaned up at all. I wouldn't expect your power to dip until 8K or higher. A clean stock port sheet builds power up to 7500.

I remember seeing a dyno chart from an F-body where the driver clutch dumped on an up-shift like he was street racing. Torque shot up to 500 or something crazy like that. If you were experiencing sharp ignition breakup I suppose you could have been shocking the driveline & dyno rollers in a similar way...

I’m not trying to flame you Vosco. Just giving my .02 on what everybody is wondering about.

vosko

iTrader: (4)

when i dyno'd it all i played with was my boost controller to keep the boost steady. i am running 4.10 gears and 17x9.5 rear wheels and 255/40/17 tires, it was a 4th gear pull. i was getting ignition break up i was running stock plugs 7's and 9's

the car ran 12.0 @ 118 mph with a broken tranny a few times(shitty driver = me ). the car is running so conservatively right now. timing is conservative. split is conservative. fuel is VERY rich. honestly i don't want to tune the car. i have broken 3 trannies, 3 diffs, 3 ppfs, one set of axles... with the current amount of power it has. i can only imagine if i fully tuned the car up to 18 psi on pump gas!


got some video of the dyno also

http://www.vosko.net/media/dyno/voskodyno-1.wmv


also here is a 10psi run



another 15psi run- this run wasn't very happy on the dyno



anymore questions lemme know

vosko

iTrader: (4)

i have three dyno charts. i did them the exact same way 2k rpm to about 7500rpm. like i said i still have lots of work to do to make those dyno charts nice and smooth

vosko

iTrader: (4)

i guess i'm the only person ??? lol

in2twins

Actually Peter did post as well. However I am still suprised at how few people have dyno sheets to back up there HP claims. It would seem to me that you have to dyno to know how much power you are making to claim it in the first place. Anyway, if any vendors are reading this show us what you've got (XS, A-spec, etc).

vosko

iTrader: (4)

woops i am blind. i didn't see peters post sorry

BDC

Yeah I've got some questions, Vosko man -- what's up with the dips and spikes in the 80 to 90mph range?

B

vosko

iTrader: (4)

i am running stock plugs 7's and 9's and it is WAY too rich so its breaking up in the top end. that is the answer to the break up

in2twins

Brian, at what boost are you making 425, and to what boost is that turbo efficient? Is that a P trim .96? Maybe I'll change out my .81 for the 96. Should I be able to make the same power with the .81, just earlier, or will the 96 make more power as well? Thanks

es

That's why I don't make any claims! I tried to get on a Clayton about 4 weeks ago, but they had an issue with their WB O2 setup, & A/F #'s was the main reason I wanted to get on it.

There's another dyno in town, & I may try to get on that one but I'm moving in a month so things are kinda silly right now.

in2twins

One word of caution to all that would dyno to establish your proper AF ratios, Most dyno places have O2 sensors that are beat to ****, and may not be particularly accurate. Ask questions, like when was the last time the sensor was replaced, how often is the o2 sensor used, etc ? Just be careful, if a shop regularly tunes rotaries, that's alot better, places that are used to pistons are used to adding a little fuel when they hear detonation. Also I think amny guys have their sensors too close to the turbo, this can be just as big a problem when your tuning. Carl

Wargasm

How do you know having your sensor too close is a problem?

Brian

vosko

iTrader: (4)

my car has a FJO WBO2 in the car at all times. i used my own wideband on the dyno even though i didn't even. i should have! oh well

RICE RACING

yeah no one noticed

I'm sure there are more boys out there who have over 450rwhp on a street set up/fueled 13B ?

I f*cking hope so, because there are about a million supras out there making a ton more than that in street trim

in2twins

This is from the TE site, in addition there have been several threads on this forum following the destruction of motors while on the dyno. In a couple of those cases the circumstantial eveidence was that the motors were far leaner than the wideband had indicated. Basicly both excessive temperature and excessive heat have a substantial adverse effect on accuracy. In one thread on this forum, and in a discussion I had with Peter at TE the inaccuracy was on the order of a full point(13:1 vs 12:1). I cannot remember the original topic of the threads that support this info, or I would do a search. Either way, there is no adverse effect to locating the sensor 18" or so away from the turbo. Better safe right?

"Wideband Sensor Positioning
The wideband sensor must be carefully placed in order to prevent damage to the sensor itself and to maximise accuracy. Also, if you use the sensor's output directly (via the simulated narrowband output) to drive your ECU then you should be doubly careful. Please follow all of these "rules" :

The sensor should always be placed on the engine side of a catalytic converter, unless you are testing the effectiveness of the convertor itself.
The gas temperature to the sensor should never exceed 850 degrees C (about 1560 degrees Fahrenheit).
The sensor should never be run without power to the WB unit (a hot sensor burns off carbon residues)
Always have the long axis of the sensor perpendicular to the gas flow (stops sensor clogging)
Position the sensor vertically or at most between 10 o'clock to the 2 o'clock position (this avoids cracking the internal ceramic structure should moisture condense internally)
We don't recommend using a short sections of exhaust pipe shoved up your tailpipe. A specially welded additional bung is the best mounting strategy.
The sensor reads the partial pressure of gases in the exhaust and infers the AFR, rather than by measuring some magical AFR directly. This may be an issue on forced induction, and in particular, on turbo-charged engines.

AFRs will indicate richer than they are, causing you to run leaner than you think.
Lean AFR's will be richer (or less lean) than indicted.
A solution is to ensure you locate your sensor away from the turbo, and certainly on the exhaust (low pressure) side of the turbo rather than the engine side. "
Hope this helps, Carl

in2twins

Yea, Peter, My 97 Supra makes 430 with a boost controller, fuel controller, and exhaust (~1500.00). That said my supra cost 30000.00, for that money I could certainly build a world beating TII