Dyno Run #2 with modded exhaust

[Jeff Williams]

Less HP 7 More Torque. Exactly the opposite of what I thought it would do.

I need to clean the air filter, and buy some higher octane gas. That should be worth a couple HP.

I made sure I bought the same gas as last week, from the same country station.

The intake temps were around 104 to 110 degrees, with the highest on run #3 of about 120 degrees. Run #4 looks the best, even though run #2 was a bit higher. We let the car cool a bit before we did that run.

I disconnected the TCU before we did the run, so it would stay in 3rd gear.

[qsiguy]

Less HP...Thats got to be dissappointing

[Jeff Williams]

It was a good 10 degrees hotter at the intake, even though the dyno room was close to the same readings. Another good thing, is that the overall HP averages were about the same, and the HP curves looked similar.

I didn't expect a lot of HP gain from the exhaust, but was suprised we coudn't get to the first run number of 244.

I was more worried about torque loss, but that didn't happen either. The before and after graphs are very similar. I did blow away the torque on the second run, but that was because I disconnected the TCU, and the car didn't try to shift into 2nd gear, so Sam could get on it WOT earlier.

It just goes to show how well INFINITI engineered the OEM exhaust.

If you are looking for power gains, look elswhere, if you are looking for some growl, just wait for my new sound clip post..... ... John's camera fouled up yesterday when we were goig to get a clip. Now I have to wait for the camera to be repaired.

I jsut spent an extra $150 so you guys can see what the results are from a custom exhaust change. Please use this post as reference whenever somebody says they are going to put Flowmasters on their Q to get "more HP". It is more like "more noise". More noise sometimes wins races, too.

[CrimsonQ]

The facts are there.

Let it be known I did mine for the sound. Which is worth more to me than the 25-30hp gain most will claim with catbacks.

Nice work Mr Williams. Sticky this one

[redmanfx]

Well, not exactly what I thought, but not that far off. The next step on the NICO Q45 information docket would be the same thing for the ------ and you knew it was coming ------ 1st Gen.

I guess that will be me sometime down the road...

[elwesso]

to be honest these dyno numbers arent really sage because the car needs a new Tstat..

[jamesmost]

to be honest these dyno numbers arent really sage because the car needs a new Tstat..

probably other maintence as well

[Jeff Williams]

Yeah, like a new LS7!

The purpose of these dyno pulls were not to show the raw HP of my engine and drivetrain, but to show you guys what the exhaust mods netted.

Do the math. 244 RWHP is not that bad, considering the engine only put out 278 at the crank. That is a 12.2% loss through the drivetrain. The 248 ft/lb of torque is a 15% drivetrain loss from the 292 at the crank.

It could use new plugs, the do have 20,000 miles on them already. It has only been 5 days since the dealership did a complete fuel rail flush, filter change, and checked all the sensors. The knock sensors do have almost 10,000 miles on them now. The injectors have nearly 40,000 miles on them as well. I saw a few specks of dirt on the air filter, which I do not accept.

I checked the temps on the pulls. The ambient temp in the room was around 90 to 94. The thermostat housing was around 194 to 198, and the water pump was about 204 to 212. The intake temp was around 102 to 112 depending on which run we were on. After the run, it went to about 120.
Modified by Jeff Williams at 8:13 AM 5/24/2006

[maxnix]

It just goes to show how well INFINITI engineered the OEM exhaust.

If you are looking for power gains, look elswhere, if you are looking for some growl, just wait for my new sound clip post..... ... John's camera fouled up yesterday when we were goig to get a clip. Now I have to wait for the camera to be repaired.

I jsut spent an extra $150 so you guys can see what the results are from a custom exhaust change. Please use this post as reference whenever somebody says they are going to put Flowmasters on their Q to get "more HP". It is more like "more noise". More noise sometimes wins races, too.

Good data, Jeff. Thank you. Now get the stock CAI and box back on!

[redmanfx]

Yeah, like a new LS7!The purpose of these dyno pulls were not to show the raw HP of my engine and drivetrain, but to show you guys what the exhaust mods netted.

That's why you da man right now in my book!! And it's very good information! Exactly the base info that will hopefully lead to more dyno runs from others to show what effect mods have to HP.

[Q45tech]

As I pointed out earlier, without data on ignition advance [stock and NICO ecu] during a dyno test impossible to say very much about such a run as the KS/ecu may be significantly cutting power back across portions of the rpm curve.

A few degrees less advance at 6,000 rpm probably only drops power by 1%, HOWEVER THE A/F ratio must be adjusted if the timing advance changes otherwise additional losses may occur.

[Q45tech]

Notice the effect of leaning a factory rich AF ratio something close to what Robert's work accomplishes percentagewise.

[RobertsnewQ]

That still seems freakishly lean to me - almost exactly one point.

Try it with the stock ECU and see what you get. On mine the stock ECU was around 11.0:1 all the way at high loads.

[Jeff Williams]

His sensor is reading the A/F ratio off .5, so it is not as lean as it appears.

Also, the stock air box will go back in on Tuesday, after I get another video for you guys. I don't need the intake noise, now that I got the noisemakers under the rear.

The next dyno runs will be with the stock ECU & NICO ECU, to show the differences. I just need to get another $150 bucks. I guess I need to make more front strut tower braces.

I had the initial timing checked Wednesday at the dealership. It was spot on.

Dennis, I noticed on that printout, the smothing was set to 0. When we changed it to 0 on my run, I got about 5 more HP on my peak.

[Q45tech]

That was just a graph I found [911] to show the effects of leaning vs power gains..............smoothing =0?

Hopefully the NICO ecu will show 24 units [hp or lb/ft] RW gain at 60F!

[sijoko]

Here's a dyno graph for a Q45 that I got off the internet a while back. Don't really have any info on the car but I am posting for reference.

[sijoko]

Here's the air/fuel graph for the same vehicle.