Many bugs were splattered. The grills from the Radiator Grill Store did a great job of preventing or slowing down the bugs before they got to the radiator; I’d guesstimate about a 50/50 split between bugs that got stopped completely and those that made it through much more slowly and in pieces. The ceramic coating I got applied the car the day after delivery made clean-up easier.
The air deflectors before the front tires caught some bugs. The deflector is slowly getting worn down as it rubs nearly every time I leave my complex.
The air turning vane smacked a bug too. The bugs provided proof of airflow patterns.
I removed the center grill screen to vacuum out the bugs that got past to the center radiator; I bought this vacuum after watching The Smoking Tire, so advertising does work. I used the attachment with the brush to help scrub the bugs off the screens and radiator while vacuuming. Because of the screen, no bugs were heavily impacted into the radiator fins and the bugs came off easily. The vacuum has two power settings and I typically use it on max power which sucks down the power quickly, but I can usually vacuum the whole inside of a car on one charge at max power. The only downside of the vacuum is that it takes a long time to charge, like an hour plus.
An indicator that the GT3 vent was working was a number of the bugs were at the very top of the radiator which required flowing upwards after going through the bumper opening; so, I’m assuming that’s due to a significant volume of airflow going through the top of the radiator and exiting out the GT3 vent on the top surface of the bumper. This picture from the center radiator installation shows the top of the duct opening is only around mid-height on the radiator.
7 comments
Khiem-
I have admired your many articles, and enjoy reading and rereading them. The title of this one sounded interesting, and the explanations, pictures, etc. were keeping me engaged, and then you casually drop that “a certain Mr. Coleman” drove your car. With you along for the thrilling ride, I assume. I’ve been onboard with Mr. Coleman’s writing, storytelling, and engineering prowess since I picked up my first issue of Sport Compact Car in late 1998. Yes, a 200-plus-page tangible magazine; remember those? I’m currently shopping for a car (a tree fell on the current ride), and that same certain Mr. Coleman is a major factor in considering the Mazda3 that I’ve been eyeing. Sorry to hijack the comments, Khiem, but I really wanted to give a shoutout to him. I hope that was alright. Thanks again for the always enjoyable and educating articles. Enjoy the drive!
I loved reading all things Dave Coleman as well! I wrote a question into SCC when I was in college and he answered it! I love Mazdas; I have a base model 2016 CX-5 that just turned 90k miles. I recently took it on a road trip with one of my dogs hitting up some of the best roads in California and it was still fun. I had to put the auto transmission in Sport mode on some sections and the transmission shift strategy was great for the twisty roads. Of course in manual mode, it has the proper sequential shifter orientation of downshift forward, upshift rearward. Lifetime average of 27mpg driving around LA. I literally just had a brand new Mazda3 sedan for a rental car and got almost 39mpg over 350 miles of mostly two-lane cruising. A lot of new cars have lane keep assist which is very annoying. Dave helped make the system be as minimally annoying as possible. The only thing that’s not optimal is the brake pad compound which doesn’t have a ton of initial bite. Though it is an improvement over a CX-30 I drove a couple years ago, but not as good as my 2016. Seems to be a bean counter change. Dave can’t fix everything. I’ll recommend anything in the Mazda lineup if you’re looking for a driver’s car.
Doing some research suggests these vanes improve front downforce and don’t do much for the rear diffuser.
https://images.squarespace-cdn.com/content/v1/5d7cfd7b13f6f06e8b55ed5c/1609096469910-BUNFCV10FN32JTZGA418/graphs.jpg
I’d found that before too. I do think it is vehicle/overall package dependent. The only thing I know for certain is that they direct air from the middle of the car outwards. I vaguely remember reading somewhere they also interact with the air swirl coming off the front tires which helps clean up the underbody airflow. I think acting as an air curtain to prevent the dirty air off the front tires from going under the rear.
This link is to an artist representation of the airflow under the GT4RS with the more extensive turning vanes array underneath the car. It does show the vanes redirecting the air outward right into where my rocker panels got hammered. Huh.
https://press.porsche.com/prod/presse_pag/PressResources.nsf/Content?ReadForm&languageversionid=1289808&hl=modelle-cayman-718_cayman_gt4_rs
My 718’s rocker panels aren’t as peppered with rocks like your is. But the under panel definitely is.
Never understood why my 718S water pump started leaking at 20,000 miles and 3 years. Makes sense. Thanks for your 718 articles, they’ve been great reading! PS I have the APR tune and wish I tried the AP…
If the car is bone stock, I think APR is a best option. It’s when you start modifying things where the pro-tune has benefits.