Micro Image/Golden Eagle Intake Manifold Review

[tmontague]

I thought I'd add my own experience to the manifold reviews so people sitting on the fence with this purchase have something else to make their decision even more difficult.

Thanks to YW member fnkngrv for providing the contact to someone who was selling the manifold. Thanks to him I was just able to make the purchase fit my very limited budget.

The current engine based mods I have and have had before the MI intake manifold are:

DC header, TRD Short ram intake, MI lightweight pulley, secondary cat delete with 2.25" piping and aftermarket turbo exhaust to the back. 1ZZ throttle body.

I had a ported intake manifold (which I am selling here) before I installed the MI manifold so I am not comparing it to a full stock set up.

The most noticeable difference with the first drive was the re introduction of the low end torque that I once had. A while back when I had a mainly stock set up with just a DC header I had gained torque down low about 400-500rpm lower on the power band. With the addition of the SRI and the custom exhaust I lost any of the gains the header gave me, albeit with the very large gain in top end power right up to red line.

The MI manifold had not hurt any of my top end power but it has given me back my low end torque. I have not noticed much sound change in my exhaust, although since I have had my exhaust installed the tone has been slowly lowering which is great, I don't know if any of this really has to do with the manifold or not.

I have noticed a change in deepness of exhaust tone at very high rpms (~5k+) it just sounds plain mean now! But normal driving there isn't any difference.

Now with daily driving when I want to shift early to go easy on fuel, I can and the car still moves enough when I can easily shift below 2500 rpm and it's fine.

During hard pulls to red line the power is awesome. For the first time I actually got some front wheel chirp doing a hard 1st gear pull. It wasn't wet out and it wasn't because I dropped the clutch. I let the clutch go slowly how I normally would but then I floored it and for a good 3 seconds the front wheel would chirp every half second or so (not squeal as in fully lost traction). I was never able to make that happen before.

The car almost scared me a little at first when I gave it WOT in first and second because it pulls a lot harder now and I wasn't expecting it.

I cannot comment on fuel mileage change as I already get lower mileage in the winter due to crappy winter gas and my driving varies between conservative and hard depending on my mood. I just put on my winter tires as well so that will hurt mileage a bit. But after 1 full tank with the manifold there doesn't seem to be any change in mileage.

I have used my ultragauge to check fuel trims to make sure I had no vacuum leaks after the install and everything checked out. Short and long term trims are within a couple of percent to one another.

The install is relatively painless if you've done some work on your Yaris before and have a good amount of tools at your disposal. Give yourself an hour or so.

*careful that you don't scratch the manifold on the hood latch when installing* I did a little but since mine is brushed aluminum with no finish you can't tell and it's nothing serious.

I removed the TB from the stock manifold and then swapped the 3 threaded studs from stock manifold to the new one. I installed the TB out of the car and then installed the new manifold w/ the TB already on it to the engine.

Careful when placing the manifold into position, it will seem like it doesn't fit. It will fit in one specific way which you will eventually figure out by moving it around slightly. Just be careful not to jam anything and watch out for the dip stick.

I had to use extra fuel line hose I had for the coolant lines from when I did the TB swap. I can't remember the size but what ever coolant line size fits the TB, it's the same inner diameter size.

The large vacuum line from the PCV valve fits fine on the manifold but the vacuum line that comes from a hard metal line from the block is too short to reach the second vacuum port on the manifold and the vacuum line from the EGR valve is also too short to fit onto the 3rd vacum port on the manifold.

Just use longer vacuum hoses and you won't have a problem.

I had to flip around the coolant hose bracket and add a washer to the stud closest to the bumper. This allowed the top coolant hose to move more to the driver side and then stop rubbing on the intake runner. Otherwise the intake runner will likely eventually put a hole in your coolant line.

*keep in mind that this manifold I purchased was used and may have been a pre production model. It did not come with the spacer that Garm from MI was selling his with. I also haven't heard of anyone else having issues with the vacuum hose lengths. Since MI is no longer in business the only route to purchase a manifold is from Golden Eagle and I'm not sure of they send the manifold with a spacer to move the coolant line over or not. I am also not sure if they send theirs with longer vacuum hoses or not.

Is this manifold worth $750 USD? IMO no, or at least not until you have a ported stock manifold with a 1zz TB and then you get bored and want more. At that point it becomes worth it if you can save the cash because it is that much more performance and it looks damn nice.

Because you get a pretty good performance boost with a 1zz TB and a properly ported stock manifold, I'd recommend doing that all first and drive it hard for a bit. Then when you feel you want more go for the MI manifold to finish it all off. But to go for the manifold out the door, seems a little silly when the $750 could be spent on other things such as a header, 1zz TB and custom exhaust to pair with your virtually free ported manifold.

All in all I'm very happy with the manifold and its performance gains and I'm looking forward to pushing it a little harder this spring hopefully in some autox.



This gives you a close up of the vacuum hose that goes back to the engine block that I had to install because the stock one as too short.


You can see the upper rad hose is about 1-2cm away from the runner after i modified the hose mount to move it over. You can also see the two new black rubber hoses, one going to the EGR and one back to the engine block.