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Discussion Starter #1
Hmmm... i don't know what to expect. I have very light modification to the car so i don't know. I never dynoed anything in my life before. Do you go through all the gears? Do you do all gears independently? Do you only do a few gears, only one? It's a mustang dyno, i heard i should expect low numbers, true?

Here are the mod list. Not very long. Its a 92' Gt with 150 000kms. Original block rebuilt head from the previous owner. 2.5inch exhaust from to back no cat, open filter. Straight powersteering belt(no tensioner) 12lbs on stock chip and turbo. Forgemotorsports subaru impreza bypass valve. Center force Dual friction clutch kit, lightened flywheel(done by a local shop, about 1\3 of weight off) Mbc to 12lbs. sometimes 14 and i don't cutoff in first through 3rd.

I think thats all the mods that can be accounted for on the dyno.
The rest is prep and light weight reduction: relocation of fuse box to far right of engine bay, hood latch removal(hood pins on) make some space for front mount.
A\C delete and tensioner delete. More space for....you'll see...hihi.

That's it. I'm expecting maybe 150hp 200tq. I hope i'm not expecting to high. Maybe more torque because of the flywheel? I rather expect low and get higher than let my ass lead and crash.
 

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make sure your boost is set to just below 12psi, or you might hit cut when you do the dyno run. what will happen (assuming you're getting a wideband as well), is they will swap out your 02 sensor with the wideband sensor. they will take off in 3rd gear at a rolling 30mph until redline. someone will be doing this for you....or they should.

make sure you post your AFR or A/F numbers. i'm curious to see what they are. you have basically the same mods as me when i ran it, except for the ps belt, and lightened flywheel. i'd expect between 155-160whp and 215-225ft-lbs.

good luck on your dyno run. :tup: your car also has 80,000km less than mine when i did my run...haha (146k miles)
 

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Discussion Starter #3
What if i don't have a speend sensor? Can the dyno calculate speed. Probably does logically thinking about how it works but as i said, this is my first time so...
 

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you don't have a speedometer in your car? but since your in Canadia, they'll do a roll from like 50km/h probably, and go to redline.
 

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lol

but isn't the 02 sensor taken out of the equation in your A/F when your at WOT?

this was taken from a site concerning chrysler imperials of all things...but all sites i visited had the same verbiage about WOT and O2 sensors..

At WOT, the computer will keep the A/F VERY rich. That way there is no chance of engine knock, or a lean condition at WOT (both of which would be harmful to the engine!). The TB position sensor is used to tell when WOT occurs (and thus when things need to get so rich). Since WOT is programmed to be as rich as the computer can make the A/F ratio, the 02 sensor is ignored (though it still operates, its just that the PCM ignores the signals).
http://www.imperialclub.com/Yr/1990/Repair/fuel.htm
and why in fourth gear and not third?
 

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Discussion Starter #7
my speedo is is busted. Not the gear the wire from the back to the the gear, the clip that supposed to clip to the cluster is busted.
 

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HotAss6GT said:
lol

but isn't the 02 sensor taken out of the equation in your A/F when your at WOT?

this was taken from a site concerning chrysler imperials of all things...but all sites i visited had the same verbiage about WOT and O2 sensors..



and why in fourth gear and not third?
Dyno's are done in 4th gear because thats the closest to 1:1 gear ratio.
 

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hmm...mine was done in 3rd gear. could i have gotten better numbers if it was done in 4th?
 

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HotAss6GT said:
hmm...mine was done in 3rd gear. could i have gotten better numbers if it was done in 4th?
Quite Possibly.
You may have seen 5 more horsepower.
Not alot really.

I was at a dyno, we did some tests with a 1st gen LX.
3rd gear was 5HP less than 4th.

A WHOPPING 120WHP 140WTQ!

Which isnt really that bad.
Lightened flywheel, and bolt ons.
 

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werd up....but i might go to a different dyno...well, a dynojet. i've heard that they give "better" numbers, but the mustangs give real world hp numbers. it's something i've assumbed since so many i've talked give me the same feedback....is this truth or a rumor?
 

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The numbers *should* be the same regardless of gear because the dyno measure the ratio of accelerating of both the tires and engine speed. This is why you can't "fool" the dyno by putting tiny 14" tires on or something along those lines.

As far as WB goes.. I have only seen dyno shops use a tail pipe sniffer. These work completely fine if you don't have a huge fart can (lets air in around it to throw off the reading) and at idle (but who cares about idle A/F... read your plugs for that).
 

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the shop i went to took out my o2 sensor and put in the wideband sensor.
 

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Don't give us this crap that the Mustang Dyno gives "real" numbers and the Dynojet gives "<notreal>" numbers... :rolleyes:

They give their own accurate numbers when compared to the same dyno.

The Mustang dyno is known to read lower, but who cares since *maybe* 10% of the dyno's I have ever heard of were Mustang Dyno's. So why go to a Dyno which won't be the same as everyone else. Unless you want to introduce the guessing game where "well I hear it's 5% lower so add 5% and that's my 'real' numbers". At that point, go get yourself a GTech and guesstimate those instead, save yourself the $$ of the rollers.
 

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HotAss6GT said:
the shop i went to took out my o2 sensor and put in the wideband sensor.
Were they smoking something in back when you weren't looking? WB O2's should be considerably further downstream than your O2 housing. :freak:
 

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why would it really matter since the ECU ignores the o2 sensors voltage at WOT
 

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You don't have to tell me this.

What really matters is that the sensor could read falsely (plus dramatically shorten the lifespan of the sensor but who cares since it's not yours) when placed in such hot exhaust (so close to the head).
 

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Were they smoking something in back when you weren't looking? WB O2's should be considerably further downstream than your O2 housing. :freak:
YEA!!! Talk about messing up a $80-$100 sensor.......
 

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Discussion Starter #19
Alright, I dynoed tonight on a mustang dyno, say what you will this guy has been doing it for some time and he stated that it was true that mustang dynos give lower number. 15-25% on fwd and 20-35% on rwd cars. anyway, heres my plot. [email protected] and [email protected]. To calculate an average of 20% higher would make it, 146.16whp and 204.24wtq. Happened in 4th gear.
I wonder if the weight of the car is considered on other dynomometers. The mustang dyno does take into account weight.
Before the dyno i checked my plugs and i noticed that i have been running lean.
And the man could tell me i was running lean after seeing the graph without a wideband plugged.Lean on the stock ecu at 11lbs of boost??? wtf? Yes lean. which would explain torque spike and inefficieny at the end of the board. Hotter combustion chamber, bad combustion, motor total efficiency goes crap, of course the turbo is no good there either. I have a gt28r in the mail and i will be comparing with appropriate fuel mods.
Link to my dyno plot. - http://photobucket.com/albums/d36/blackxrockx/?action=view&current=dynorobsmxgt01-11-05.jpg
 

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Congradulations on having a plot you can't compare to anyone else unless you say "well just add 15-25% to mine and we can compare it to yours". :lol:

Is this car stock?.. stock boost on the stock chip that might be "ok".
 
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