Time for a new dyno run

[FunkyBuddha]

I'm going to dyno my car again after the failed dyno the 1st time producing higher than normal whp numbers. And the fact that I'm going to put in an order for the Ion p5 catback. Let me get a checklist going and you guys can help me out too on stuff I am missing and what I should ask.

1. run in 3rd or 4th gear
2. make sure a fan is blowing
3. corrected for altitude
4. corrected for humidity


what else? I dont' really understand the corrections thing. Someone want to explain it to me? What do I tell the dyno operator?

 

[twilightprotege]

personally i prefer running in 3rd gear

and run with the hood closed

 

[Gen1GT]

I run in 4th with the hood open. Running in 4th will give you a smoother power band(on the chart), and a more accurate measurement. The dyno operator should automatically correct for temp, humidity and air pressure.

 

[twilightprotege]

i like the hood closed because that way it's like you're on the road and the perrils of heat in the engine bay play a role

 

[scorch70]

I run in 4th with the hood open. Running in 4th will give you a smoother power band(on the chart), and a more accurate measurement. The dyno operator should automatically correct for temp, humidity and air pressure.

I have to agree with Josh on this one. I run in 4th gear with hood open. Where I go, they dont have a great fan, so running with the hood closed would be death. If the place you dyno at has a huge freakin fan, then maybe you could go with hood closed. Maybe someone should do a comparison and see how much diff it makes. Should make less of a diff on n/a cars than turbo I would bet.


just imho,

 

[vindication]

run in 4th, it's the closest gearing we have to 1:1

 

[twilightprotege]

see i've always heard that we need to get as close as possible to 1:1 but not under. 4th is under 1:1, so 3rd is the gear of choice

 

[FunkyBuddha]

Booked my dyno time on a dynojet for next Thursday. Hope this goes better than the first time.

 

[Gen1GT]

My 4th is 1.030. Why is it you shouldn't do a run when it's less than 1 Andrew?

 

[Fear]

see i've always heard that we need to get as close as possible to 1:1 but not under. 4th is under 1:1, so 3rd is the gear of choice

all dyno runs should be made in the gear that is closest to 1:1, whether it be a bit above or a bit below. if you go to a shady shop, they may try to convince you to run in 3rd gear because, uncorrected, it will appear you have made loads more power. it happens, not all dyno shops are honest about things.

 

[twilightprotege]

i dont understand the reasoning behind not going below 1:1, but i have read it several placed and a few different shops around have said the same thing.

in terms of loads more power, that's not true.

 

[Gen1GT]

What gear you're in doesn't matter. Torque is multiplied by gearing, but wheel speed is directly inverse to that, so it cancels it out. My experience is that 4th gear is the best compromise between time and a good smooth run. In a lower gear, a driveline shutter shows up as a huge blip in the powercurve.

 

[twilightprotege]

i guess the main thing is stick to the same gear for ever. i've had all mine done in 3rd and will continue to do that

 

[srad2drag]

I have dynoed my car in 3rd gear and 4th gear.From my experience my car has more hp dynoing it in 3rd.
For example I went to the dyno last night and what I do is I tune my car in 3rd,why because its a shorter run and its also easier on the motor ie:10 sec run in 3rd compared to 20 sec run in 4th. Then When I finished with my tuning I will make a final 4th gear pull.
Just so happened lastnight I made 142.6 hp in 4th gear and 143.9 hp in 3rd gear.
This is with some tuning. I had baselined at 124 hp so we made 3rd gear pulls while changing ignition timing and fuel pressure.

 

[Gen1GT]

I have dynoed my car in 3rd gear and 4th gear.From my experience my car has more hp dynoing it in 3rd.
For example I went to the dyno last night and what I do is I tune my car in 3rd,why because its a shorter run and its also easier on the motor ie:10 sec run in 3rd compared to 20 sec run in 4th. Then When I finished with my tuning I will make a final 4th gear pull.
Just so happened lastnight I made 142.6 hp in 4th gear and 143.9 hp in 3rd gear.
This is with some tuning. I had baselined at 124 hp so we made 3rd gear pulls while changing ignition timing and fuel pressure.

Hey, nice to see you on here! It's good to see another BP tuner on the NA Tech forum. You should make a post telling your story, mods and gains etc.

How far did you go with ignition timing, and what were the gains? It looks like you got gains with those cams now...

 

[srad2drag]

Hey, nice to see you on here! It's good to see another BP tuner on the NA Tech forum. You should make a post telling your story, mods and gains etc.

How far did you go with ignition timing, and what were the gains? It looks like you got gains with those cams now...

Yea I often visit this siter when I'm surfing...Just so happen I seen this thread and thought I would reply also.
As for the timing I started off with 16 degrees.I already knew the
car was going to ping on the dyno but I did not want to change anything after doing the cam work.
So the first pass was 124 hp and it pinged the whole run.
The next pass we backed the timing off 14 degrees and we made another pull
the numbers rose to 141 hp.So with that much of a increase we backed off again to 13 degrees timing adn we also added a couple of pounds of fuel pressure...The result was 143.9

I had 87 oct. in the tank(you know me) I thought about putting in 89 but,with this car I make the most hp on 87.

 

[FunkyBuddha]

Sweet^^....thanks for all the info. The day is near.

 

[Gen1GT]

Yea I often visit this siter when I'm surfing...Just so happen I seen this thread and thought I would reply also.
As for the timing I started off with 16 degrees.I already knew the
car was going to ping on the dyno but I did not want to change anything after doing the cam work.
So the first pass was 124 hp and it pinged the whole run.
The next pass we backed the timing off 14 degrees and we made another pull
the numbers rose to 141 hp.So with that much of a increase we backed off again to 13 degrees timing adn we also added a couple of pounds of fuel pressure...The result was 143.9

I had 87 oct. in the tank(you know me) I thought about putting in 89 but,with this car I make the most hp on 87.

Dude, we need to see you on 94 octane. You're seriously held back there. My car didn't ping at 22(but also didn't make any power there). Another 5 of timing with good fuel, and there's no reason you won't have close to 150whp.......

Still, 144 is pretty darn good for the stock bottom end and ECU....