It will be interesting to see if this drops your intake temperatures quicker once heat soaked from idle time.
I've had my eyes peeled towards diverting air from these portals someone thought would cool the brakes. IMO without plumbing to the spindle/rotor, I'm 99% certain they simply push air under the nose... Sure there may be a low pressure area around the tires circumference but to push air through the rotor with no duct work seems very unlikely. Where is that windtunnel when you need it??

Reference is these ducts in the lower grill (gills).


So far all they have done is made it very difficult to install LED bulbs in the turn indicator sockets. Wait; maybe that was the blinker fluid reservoir in the way?

 

C, take a look at post #58 here for a clean-up tip regarding the OEM applied black overspray. It's like 20 min or less to make the core support a little more appealing.

 

That would require a significant modification to the headlight and the rainy seasons here in Florida could spell disaster if I give the heavy rain a direct inlet to my air intake box. The angled air inlet that goes from the grill to the headlight access hole should be a good compromise and hopefully prevent water inhalation.

It was actually the brake ducts on my lower grill area that gave me the idea on diverting direct air flow from the grill to the large access hole behind the headlight.

BTW, I've collected several days worth of data under different temperature conditions and I'll be able to address your inquiry on the drop of intake temperature on an upcoming post. I just need to compile the data on an easy to digest visual reference for all to see.

In short, it's a worthwhile modification for those that utilize a secondary intake hole within the engine bay.

Thanks for the tip. Sounds like a future project the next time I mess with my intake system. The OEM black overspray on the core support is definitely unappealing but luckily the front trim piece discreetly covers it.

 

As mentioned in one of my earlier posts last week (post #734), I experimented with a ram air duct design to see if it would have an impact to my MAF g/s readings on my datalogs. Below is a pic of the ram air duct I inserted behind the front upper grill which leads directly onto the headlight area via an access hole that I created. The intent is to provide a ram air effect with cooler denser air entering into the engine bay and being utilized by the secondary intake hole located on the F-Sport lower intake box.



Before I go into the results of my findings, I need to reference my earlier MAF g/s results from previous experiments (3IS350 F-Sport Intake Pipe w/ Sound Generator vs 2IS JoeZ intake pipe; F-Sport Lower Intake Box vs Enclosed OEM intake box) which can be found on post #697:

( https://www.clublexus.com/forums/bui...l#post10600672 ).

Here were the results of the MAF g/s comparison between the F-Sport Lower Intake Box vs Enclosed OEM intake box which was done during the summer time last year:



Here were the results of the MAF g/s comparison between the 3IS350 F-Sport Intake Pipe w/ Sound Generator vs 2IS JoeZ intake pipe which was done during the winter time of last year:




With regards to the ram air duct experiment, I did multiple WOT pulls in 3rd gear in various temperature conditions during the past few days which are reflected with the different Intake Air Temperature (IAT) readings. As Florida experienced some of the coldest recorded temperatures within the past two years, I felt it was the perfect opportunity to see what my peak MAF g/s reading would be with near freezing temperatures. Below are my results of the ram air duct experiment:




I recorded my highest MAF g/s reading ever which was 256.32 g/s. Though it was higher than the previous peak MAF g/s reading from my previous experiments, the IAT of 46 degrees was likely the main contributor to such a high number. When comparing the ram air duct MAF g/s readings to my previous setups and datalogs, I did not notice any significant MAF g/s differences that can be attributed to the ram air duct. As such, I believe that the ram air duct I experimented with has no impact to increasing the MAF g/s values.

However (gotta love those howevers), I did observe that the IAT readings were much closer to the outside temperature readings using the ram air duct. With the ram air duct, IATs were typically around 4-7 degrees higher compared to ambient temperatures. Without the ram air duct, my previous IAT was on average 10-14 degrees higher.

Based on my analysis from when the IS350 was heatsoaking while idling at a stoplight and then moving at cruising speeds (45-50mph), the IAT temperatures also dropped significantly quicker using the ram air duct than without.

In conclusion, while a ram air duct (at least the style I built) will not have any noticeable gains to the peak MAF g/s readings, it will greatly help with ensuring an abundant amount of outside air is available for the secondary intake hole to utilize which will keep IATs low and ensure peak performance of the engine and greatly reducing heatsoak. This ram air duct design/concept might also help those with aftermarket short ram air intake systems that include a cone filter design and heat shield.

 

Nice R&D there! You should now sell custom cut pieces of lawn edging on CL here as a "ram air intake accessory". LOL!

 

Just plastidip the edging in a carbon fiber design and it will look like a passable aftermarket part.

For those that want to do a similar mod, I recommend trimming a small piece of the panel that resides inside the upper grill/radiator area in order to create a larger opening for cool air to enter behind the passenger-side headlight area. I trimmed just enough for the clip to secure the upper portion of the panel:



For this crude version of the ram air duct, I used a piece of landscape plastic edging that I had sitting in the garage.



The curvature of the plastic is perfect for having both ends of the trim piece secure properly on the horn and partially tucked inside the access hole. For the piece that I used, the height is approx 4.75" and the length (when cut) is approximately 11.5". I just checked the ram air duct this morning and after multiple WOT pulls in third gear, the piece is still secured perfectly at the angle I left it. No added NVH or any negative side effects.



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C, question; when you long press and disable trac, do you notice the trans shifts significantly firmer? Like a big kick in the pants firmer? Not wanting to spin up the new tires I was surprised at how different it behaves....

 

Not sure. My transmission usually shifts smoothly when left in auto and downshifts are firm when in manual mode. No difference that I can tell when stability control is on or off.

It's autocross day tomorrow and what better way to enjoy the event then to bring your kids along for the runs. I have helmets for both of my kids so they'll be strapped and ready for some high-g fun.

 

oh it is smooth and nice, just more nicer, more firmer! Takes on an aggressive touch as it should when playing!


Have fun and be safe....

^^ have the wife take the Convertible and you can both take one! Haha!

 

Hope you all had fun and kept safe! Post pics when able!

 

The autocross event over the weekend was lots of fun, especially since this was the first time I had a chance to complete an autocross in the rain! It was raining cats and dogs when I was driving from my house to the event location and while the heavy rain subsided during the competition, it was still lightly raining and the course surface was completely wet.

As noted on my previous post, I brought both of my kids to the autoX for them to ride along with me on all of my runs and enjoy some performance driving in a safe environment. My original intent was to keep the car slightly below the limits and treat the timed runs as fun runs as my focus was more on the kids than competing for the best time.



As it was unexpectedly raining during the event, I initially decided to leave the stability control on for the first time as I was carrying precious cargo. Nonetheless, the wet surface would give me an excellent opportunity for me to test out both the VDIM Sport stability control setting (which is a feature available from the IS-F Steering ECU) and the capabilities of the OS Giken TCD under wet conditions.





I was pretty impressed at how minimally intrusive the VDIM Sport setting was when I did my first two runs through the course. Though I kept the limits of the car to around 8/10-9/10 for safety reason, the stability control icon hardly flashed and I noticed almost no interference from the braking system or engine power cutoff. The only time I noticed the stability control flashing was when I was in the middle of a slalom portion of the course at the higher RPMs of 2nd gear. Not too shabby.

For my third and fourth run through the course, I decided to turn off stability control to see if the performance envelope would increase as I felt confident at not losing control of the car. Sure enough, the OS Giken was monumentally instrumental at keeping the rear tires planted under wet cornering conditions and I had no abrupt oversteer coming out of the corners (which can’t be said for many of the other competitors).

Though I never intended to go 10/10 at the event for the fastest time (mainly because of the additional passengers), to my surprise, I ended up getting second place that day. I think my attempt at being as smooth as possible through all corners actually helped me be quicker than I anticipated. All in all, it was a great learning experience with keeping the IS350 stable under wet conditions and my confidence in the vehicle build is certainly up there.

Maybe at a future event but I did have my son help out with washing the car on Sunday. I'm getting him used to the life of owning a car.

 

2nd place overall or just in your category/group? Regardless, glad you all had fun and kept safe in the wet! You can really tell who are true "drivers" when you throw a little water on the course.

 

1st place in my group/category and 2nd place overall. A wet course definitely forces the driver to be extra smooth with all pedal and steering inputs.

Maybe next time I'll add a cup of water ala Initial D

 

Nah, no water over the lip of the cup means you're not pushing it hard enough. LOL!

 

Very Nice! Glad you and everyone had fun!

As drivers I think people that don't wreck sh%t typically are smooth drivers like yourself! You can get at more from the car during transitions over sketchy surfaces if you're smooth!

For anyone driving or riding for example a 'street motorcycle'; being smooth is fast and being smooth often times means you walk the next day. Ha!