Best Free mod we have tested

[Dave@ddmworks]

So we are back doing some more Sonic development after catching up with some old projects and hiring some new help to cover the growth.

One of the things we have been wanting to test here for awhile is the removal of the air dams in the intake manifold. For those that are not familiar with them, there are some small air dams in the intake manifold that have a small hole in them. The thought is that they are there to introduce turbulence in the intake runners which will help with the atomization of fuel, a more homogenous mixture leading to better fuel economy.

We have received feedback from several people that have removed the intake manifold and removed these walls that seat of the pants "butt dyno" said that it made a difference, so we wanted to actually test it out on the dyno to see if there were any gains.

We bought an extra intake manifold for the testing so that we could still have a stock intake manifold for testing later and give us the chance to do A-B-A testing.

We started out installing the new intake manifold on the car to make sure both stock intake manifolds made the same power, which they did. We then modified one of the intake manifolds and drilled some extra holes in the air dam to see if there was any power difference. With the extra holes in the intake manifold, we picked up 4-5hp consistently which was more that we honestly were expecting.

We then installed the stock manifold back on the car and the car returned back to the stock hp.

Then the intake manifold with the 5 holes in the air dam had the air dams completely removed so that the intake runners were nice and smooth, and that modified intake manifold was installed. The HP increase was very noticeable, the graph below shows the car with a stock manifold (blue line) and the modified intake manifold (black line). The peak numbers increased by 14HP and 11 ft/lbs of torque, not bad for a mod that is free, just takes a little time to do. The gains all the way through the power band are impressive. Our fuel trims still look good on the car and we are testing what it has done to our fuel economy and will report back on that. We are expecting a hit on the fuel economy, but will gladly take it for the new increase in power.

All other mods on the car where not changed during any of the testing and consist of - DDMWorks Intake, DDMWorks prototype exhaust, tune.

 

[sx sonic]

Hey Dave, thanks for dropping in and giving us the skinny on this mod and doing some great testing. It's nice to see our butt dynos confirmed (we know how reliable they can be ).


I don't expect you to see much hit in fuel economy, I never saw a quantifiable change, but you probably have some better metrics to test with than me.

 

[Foxbox]

Does removing the air dams cooperate well on the stock calibration?

I would love to gain that extra bump in power. I just can't sacrifice being able to flash the stock calibration on the car for dealer visits.

Any testing of that Dave?

 

[cndctrdj]

Would love to see the fuel hit. And I cant believe that you gained so much power

 

[SuperFudd]

Dave,

Please confirm you key of the 1.4T.

 

[Dave@ddmworks]

Does removing the air dams cooperate well on the stock calibration?

I would love to gain that extra bump in power. I just can't sacrifice being able to flash the stock calibration on the car for dealer visits.

Any testing of that Dave?

We can flash back to stock and see, however the fuel trims are in an acceptable range so it should not matter.

Would love to see the fuel hit. And I cant believe that you gained so much power

We will see how it does on fuel now, we could hardly believe it also, but we ran several runs in each configuration and the runs for each mod lined up nicely with each other.

 

[Preloader]

Finally some real world data on this mod.

Thanks Dave. This is great news.

 

[Stew]

Does removing the air dams cooperate well on the stock calibration?

I would love to gain that extra bump in power. I just can't sacrifice being able to flash the stock calibration on the car for dealer visits.

Any testing of that Dave?

I have a stock tune and I ported my intake manifold, runs great.

 

[sx sonic]

I have a stock tune and I ported my intake manifold, runs great.

Same. I didn't have an UltraGauge at the time to monitor LongTerm Fuel Trims.

 

[$ub$onic]

What should the fuel trims be under ?

 

[Dave@ddmworks]

What should the fuel trims be under ?

We like to see short and long term combined under +/- 10% in closed loop. Check engine light will not come on unless you get over 25% on the long term if I remember right on these cars.

 

[ScarabEpic22]

What should the fuel trims be under ?

In an ideal world, 0. Usually, you'd like to see +- 2-3 but it would require a tune (usually an in person one to account for small manufacturing variances).

If you're within +- 5-7%, it's ok. Not ideal by any means, but ok. Remember trims account for manufacturing and fuel quality variances and mean the ECM is adding or subtracting fuel to compensate. Ideally, there would be no compensation and the engine would run at the ideal/commanded EQ Ratio (AFR) all the time, but we live in an imperfect world.

 

[$ub$onic]

We like to see short and long term combined under +/- 10% in closed loop. Check engine light will not come on unless you get over 25% on the long term if I remember right on these cars.

Mid-wot is spot on

Idle-light is all over the place. Sometimes light is good depending on condition.

Should I be concerned?

 

[Maddog2020]

Please help a Nublet!

As a novice, I'm not sure how to remove the air dams in the intake manifold. A picture would be great! Please don't laugh too much. I currently only have a full tune from BNR, no other mods.

 

[gdideric]

am i reading the graphs wrong? but it looks like the mod punches a hole in the curve right at 3k rpms...which would be an annoying place to fall on it's face.

 

[cndctrdj]

It does not look like you are reading it wrong. It seems to me that it could be a cam change thing at that rpm. Or a computer related thing. Something a tune could get rid of

 

[sx sonic]

Mid-wot is spot on

Idle-light is all over the place. Sometimes light is good depending on condition.

Should I be concerned?

Check them during steady state cruising, It's the only reliable way to check them without being an engineer or good tuner.

Flat road and set the cruise for several miles or lock your throttle foot to a set position.

 

[$ub$onic]

Check them during steady state cruising, It's the only reliable way to check them without being an engineer or good tuner.



Flat road and set the cruise for several miles or lock your throttle foot to a set position.

In something like that, my long term is 0-1.5 at the most and short is 1-2

 

[sx sonic]

As a novice, I'm not sure how to remove the air dams in the intake manifold. A picture would be great! Please don't laugh too much. I currently only have a full tune from BNR, no other mods.

Maybe this will help

http://www.sonicownersforum.com/forum/do-yourself-articles/4410-porting-intake-manifold.html

 

[Dave@ddmworks]

am i reading the graphs wrong? but it looks like the mod punches a hole in the curve right at 3k rpms...which would be an annoying place to fall on it's face.

There is a dip on both the stock manifold and the modified manifold around 3k rpm's, nothing you would feel driving.

In something like that, my long term is 0-1.5 at the most and short is 1-2

That is pretty good for fuel trims.