Is my front undertray too long?
 

Is it? Do you think it will trap too much of the under-hood heat? My first test drive with it on showed no overheating problems...

Here are some pictures, I do not pretend to believe it is pretty. I should have made one in cardboard first and then attempted with the ABS but oh well. I know it's ugly, I know it's not symmetrical, etc. etc.

Unmounted
http://img206.imageshack.us/img206/1...00largegb6.jpg

Mounted: front view
http://img237.imageshack.us/img237/4...07largejd2.jpg

Mounted: rear view
http://img527.imageshack.us/img527/7...08largegk8.jpg

i think it looks great and don't think you will have heat issues. should help draw air from the front of the engine bay out that back past the trans

You shouldnt have any overheating issues.

Im sorry for the off topic question, but I see you have an LC1, where is ur controller stashed?

looks good
sam-mine is under the center console in front of the shifter.

^ Really, and it reaches all the way down. That is very very good to know.

looks good to me, what material did you use?

He mentioned it was ABS in the first post.

sorry i should have clarified, i was looking for specs, like how thick itis and how big the sheet you had to buy and where you got it?

i do want.

Looks pretty good. Better than spending big bucks for someone to make one for you. And honestly, how often are you gonna see it anyway?

One suggestion (something I plan to try) is to use some sort of 1/4 turn fasteners to facilitate removal for maintenance access.

looks great
it will help your cooling actually, your engine bay is all about pressure as it doesn get much airflow once past the radiator, this will help direct air out the back

Anyone have measurements of this stuff? Cause my car is still sitting in snow.

Ok, I will try to answer everyones questions.

First of all it's 1/8" thick ABS plastic. I bought a 4' X 8' sheet of it from a local plastics supplier, I think it was about $55 total. I still have quite a bit left over, a 4' X 6' sheet would have been enough. Check the yellow pages for a plastics supplier near you, they should have ABS sheet in various thicknesses.

I'm not sure what rleete means by 1/4 turn fasteners. I do need a better way to fasten the undertray to the front lip. As of right now it's kind of a pain in the butt to take off and reattach.

I know the undertray will help cooling. The whole reason I built it was to help cooling and hopefully increase front downforce. Having an undertray reduces the amount of air that goes under the nose of the car and forces more air to go through the radiator (increases pressure in front of the radiator). My fear was that the tray was too long and would possibly block some of the airflow out of the engine bay. I had read that if the undertray is too long it can cause problems.

Sam: I have a PLX M300 wideband not a LC-1. I have the controller smushed between the center console and passenger seat...

Thanks to everyone for the compliments. I don't think it's pretty but I sure hope it's functional.

I think rleete was refering to Dzus fasteners.

It looks good and will be copying it as soon as i can find a local plastic supplier and cut up my hood.

could you give us a measurment of the finished product?

Very nice, adding this to the list of things to do.

The longer the better, a flat underside = better aero.

Looks good.

I am considering doing one from aluminum.

You should make a cut out for your oil drain plug to make things a lot easier.

But if he got some of those 1/4 turn fasteners, he wouldn't need to because it would already be easy to remove yah?

True but to remove 8-10 fasteners versus having access from a cut out would be quicker/less hassle. To each their own either way great job.

Yes, that's the type of thing I was thinking. But, Dzus is a brand; one among several. I mostly use Southco at work, but they're all pretty much the same.

McMaster-Carr sells them. Can also get them through other places, but I'm not sure if you can find them in the average auto parts store.

I think it's great. If it becomes a hassle to remove, then change it later. Now get some data and show us it works! ;) btw- I don't think it's a good idea to have your WBO2 sensor point up (past parallel to the ground/chassis)... regardless of who makes it.

What sort of fasteners are these? I have a desk job so I'm not familiar with the terminology.

Very nice, I like it.

I have a few questions about undertrays.

1. Is plastic really the best material to use? Doesnt it get hot in that area?

2. Is this -only- to to increase the effectiveness of the radiator/cooling system?

3. Does it noticably reduce drag?

4. What is the rear-most part of the undertray connected to?

5. What, if any, are other noticeable effects of the undertray?

Would these work to hold it on if they are fit tight?
http://www.pegasusautoracing.com/Images/M/3045-2006.JPG
http://www.pegasusautoracing.com/pro....asp?RecID=779



BTW sorry to thread-jack.

I would like to know and see some data about reduced drag and more efficient cooling as well. Looks like it would be a fun project. Have you guys ever considered putting a triangular shaped piece in front of the front wheels to curve it around them? I read some article about trays and this on a prius and I think I remember something like 33% of the drag in the front is from your front wheels. If you have a splitter does the undertray still help reduce drag?

Found the article here, you guys should check it out. It's definitely a cool read.

Browser Warning

Here are some images from the article that may be helpful...

http://img161.imageshack.us/img161/7945/245624lobs5.jpg
http://img17.imageshack.us/img17/7115/245628mgqo7.jpg
http://img27.imageshack.us/img27/595/245629mgat1.jpg

I'm also curious about this... i googled and found this:
ABS Acrylonitrile Butadiene Styrene

Indicates melting point is a little over 200 degrees F which isn't really out of the question is it? especially if the tray ends up in contaact with some hot pipe or something?

Another site says maximum "service temperature" is 185 degrees.. Wikipedia says the heat from a "wood fire" can cause it to boil and light up in a spectacular way :eek:

I need to build an undertray soon to, but i'm wondering if there's a different material more suitable. Aside from the sharp edges, what's the downside to aluminum?

-Tomaj

I've had no problem with my ABS undertray. It doesn't come in contact with any really hot parts but it is close to the downpipe. I haven't noticed any heat damage to the tray though.

Back on to the subject of the LC-1. I thought that you weren't supposed to mount them below horizontal otherwise moisture would condense and ruin the sensor. Just something to think about if you can rotate that pipe.

Not to mention it would increase the clearance for the awesome undertray. I'm definitely putting this on my list of things to do. I like reddroptop's idea of using aluminium but can I justify the extra weight or more importantly the extra cost!!

isn't the stock undertray abs? I use an abs one I made also and haven't had problems.

It's not an LC-1. It's a PLX M300. Either way it probably shouldn't be mounted like that, bummer too bad...

Seems to be working fine and I have more pressing issues...

ABS is commonly used for under the hood applications. In fact I am making my undertray/splitter/ducting out of ABS right now as well. I plan on posting pictures when it is complete.

ABS is also what most factory sport bike body panels are made out of; they see a lot of heat too. Typically there is only a couple of inches between a body panel and the engine and/or exhaust.

good to hear.. I'm currently waiting on some silicone for my new intake tract, then comes the cold air box. After that, undertray :facepalm:

So, how does it perform?

:withstupid:

I love that smiley :)

but all the fairing on the sports bikes are made from abs as well. Matter of fact my old Ninja had less than a finger clearance (less than 1/2") between the pipes and the fairing and it never got burned.

[QUOTE=ZX-Tex;427833I plan on posting pictures when it is complete.
[/QUOTE]

Anything come of that statement?

Yeah sorry been busy dealing with the engine rebuild and the LS1 car. The splitter is in and working great. I have had it over 100 mph and it stayed put. I'll get some pictures up as soon as I can.

I will also be making another one for the LS1 car soon. That one will be track tested, and will be larger as well, with more forward protrusion.

ZX-Tex, are you also planning on having the splitter stick out or will it just line up with the bumper? Also will the bottom part of it be from the same piece or will they be cut separately (like splitter made from 1/4" abs and 1/8" for the undertray)?

The one I have finished on the street car sticks out about 2" from the bottom of the bumper. It looks good IMO for a street car, not too excessive. The one for the track car will probably stick out an inch more.

It is the same piece all the way back to the front edge of the wheel well. After that, the stock undertray takes over, cut to fit.