Geez - Jus' statin' th' facts...

BTW, thanks again for the great deal on the exhaust.

Dave

 

color me curious. What are your thoughts as to why not have a catch can? Are your thoughts applicable to only single turbo cars or twins-cars as well?

 

So how are those fender vent meshies workin' out for all you playas?

 

I was thinking of something else, lol too much of a rush to get out the door. Upcoming car show has me going crazy sorry for the rambling mis-placed comment lol

 

Another idea that looks nice that i have done for a few people is Overlay real carbon over the liners or also wrap them in 3m carbon vinyl

 

^ Really interested in that!

 

I'm not totally sold on this yet. All this airflow dynamics stuff is such a black art. And its something that is so hard to quantify. Underhood temps sure. I could see it droping those. Same with the removal of the rear weather strip. But consider this. These things are sealed for a reason. And that reason is the result of extensive wind tunnel testing. As for the pressure of the area at the bottom of the windshield. If you want to see what happens there, tape a few pieces of string to the hood near the base of the windshield and watch as you accelerate and they get sucked into your engine compartment. This stuff doesnt always work like you think.

The only concern i have with this modification is, does it have a negative impact on the aerodynamics of the car. A car that is blatantly and obviously the result of A LOT of wind tunnel testing. I dont have a wind tunnel or much of a back ground in aero dynamics. But i have enough of an understanding to be wearey or people who think they do. I have seen this kind of behavior with ducting of intercoolers and oil coolers. Which had very nice write ups on how to make an improperly designed duct. I'm just saying that without some kind of imperical evidence i'm not sold on anything other than this will drop underhood temps. Snake oil is back in fashion on rx7club.

 

^ I agree with you. There are a lot of engineering aspects to the rx7 we dont know about. I wish we had the chief engineers personal journal so maybe we could have a better idea as to What they were thinking when designing. Although Mazda engineers really spent time designing and engineering, they werent all perfect. With new cars hitting the streets and track, equipped with freakish technology (especially in aerodynamics) I really do appreciate rx7 members who try to constantly improve our 20year old machines.

What I think will be an effective means of "air-tunneling" will be to somehow* duct the back of our oilcoolers over the fender liner and exit where the fender vents are. This MAYBE add a bit of front downforce as well given the routing and size of the opening. Ive heard or read that the stock fender vents are semi-function but I really doubt that.

I do believe that the mesh fender liner idea is good and effective only if air has somewhere to exit. Maybe by the fender vents or like the panspeed fender slits.

 

When a new model of RX-7 is released Mazda commissions a book to be written about it and that is a good place to begin trying to figure out what the engineers were thinking.

Pg 67 of Yamaguchi's 1992 book RX-7 has the airflow schematic for the oil cooler ducts that exit behind the front wheel with the text on pg 68 describing it as such-

"One of the small intakes is for an air-cooled oil cooler (both of these small ducts are used for the R1 model's twin oil coolers). Heated air from the cooler is led through a duct inside the top of the wheel arch and exhausted through the sculptured duct behind the wheel opening. As benifits a car of the RX-7 concept, image and purpose, all inlets and ducts are fully functional."

 

^exactly. The oil cooler ducts are functional and tied into the fender vents. A good upgrade for them likely would be resealing the ducts that are stapled to the fender liners so that the fender vent does a better job of moving air past the oil coolers. I'm not saying anyone is dumb here. Please dont interpret what i was saying as talking smack. I do appreciate that everyone is still trying to improve their 20 year old rotary beauties. Some really great mods have come from this behavior. Howard Coleman has heavily supported and promoted the use of ai which has likely dispelled many peoples fears of the systems. Someone came up with the great find of the fast acting intake air temp sensor. Lots of good stuff. But itis all stuff that you can prove. I'm only trying to make sure that everyone is careful about making modifications like this. Our cars have a great drag coefficient that works in our favor. I dont want to ruin something that so much work was put into. Only now are many cars catching up to the drag coefficient that our car had back in 93.

 

This thread isnt new and many have been running this way for years. Most recently a friend performed this mod and noticed an immediate difference in engine bay and coolant temps. I can ask him this weekend for more specifics.

Edit: being that i started this thread i take offense to your underhand jab hank. You pop back up on the board with comments about snake oil being in fashion.... really? Good thing we have you to keep us on the straight and narrow

 

I'd be very interested in actual water/and or oil temp comparisons. Just read thru the various threads and links and don't see anything concrete as of yet and this issue has been around for some time.

Don't care too much about the aerodynamics issue, but if this did work for lowering temps I'd be all over it.

So for those of you that have done this, how about some before and after comps of temps? Rich, how about taping up your mesh and then doing some tests so we can put this issue to rest?

What I am most interested in are at speed temp measurements. My temps go up when I go faster. So, at 60 MPH they are less than at 80 MPH. Any tests for this would be great.

And yes, I know I need to put my under tray back on and do better ducting. Going to tackle my temp issues in the next week or two and would like info on all possible things that would help, including this mod potentially.

 

water and oil temp comparo's would be nice. Should be relatively easy experiment of before and after....

Cooling advantages win over aero on a DD IMO.

Where can I get snake oil...that better than syn or dyno?...debate....lol

 

^ Yup, that is what I am thinking. My fender flares are looking pretty bad so I might just do the testing on the old before installing new ones.

 

Bumping this up as I am going to tackle my cooling issues next week. Anyone done this with actual results on water/oil temps? Anyone willing to measure temps with the mesh inserts and with them taped/covered up?

Anyone? Bueller, Bueller?

 

David...this is the forum...no one wants to actually back up what they say lol.


just kidding guys...seriously, would be cool to have this documented for the community

 

Well, it appears that no one has done any testing with this regarding water/oil temp improvements so I will probably do it next week if Steve Osley feels it is a good idea or at least won't hurt.

I've got a couple of goodies showing up to help with my water temps and will add this to the list.

 

I meant no offense. Seriously. Internets arent good for inflection and such.

Your welcome!

 

Hank, I've got ya. No hard feelings

I've always viewed this 'mod' as something that would give incremental (read: minor) gains when it comes to things like water temps. It helps to keep the engine bay environment cooler, which is enough for me

 

Anyone have data on this?