Correx (Coroplast) arrived today :) - Gas Savers

landspeed · 03-26-2007, 01:32 PM

OK. I received my pack of coroplast today, and have done some mods.

(1) Lower grille block, and upper grille block (white layer behind the grille)

(2) Small rear wheel skirts (but must do something!) (Also note the folded-back mirror, also to reduce drag!)

(3) Partial front undertray (no pictures yet as it was too dark by then)

I will now have to see what effect these mods have on my FE. Any guesses as to whether I will see an effect?.

I have loads more Coroplast and am considering a rear boat tail, although wonder what response I would get when driving round (the rear wheel skirts aren't too prominent and the rest of the stuff is quite discrete). Any comments on what I've done?

Edit - P.S. It is pretty good having a white car - I can get Coroplast and Duct Tape in the same colour!

zpiloto · 03-26-2007, 02:04 PM

Very nice and clean. Can you come any futher down on the skirts or is that where the buldge starts? Might want to put hub caps on the list, those don't look to aero friendly. I think a boat tail would certainly help also if you're the only one in it most of the time you could duct tape the other 3 door handles. Be interesting to see your results. Did you every get the SMID working?

landspeed · 03-26-2007, 02:32 PM

I'll be able to get the rear wheel trim to just above the middle of the tyre - after that it would scrape the tyre!. It was getting dark so I did the (dodgy) undertray instead. I hope it doesn't flap in the wind (the front is very well attached, so it won't rip off, but the back is attached in various placed with duck tape...

I can't get hub caps, because, those are actually alloys!. If I can afford it one day I would try to get some rims that can take the LRR insight tyres, and use those instead. I would consider getting a shiny disk hub cover, and attaching that to the alloy (probably with 4-8 cable ties through the alloy spokes).

The SMID is almost working - the unit itself is perfect, it is just that my car has a weird injector system. It is going to be a few weeks before we get the time to sort it out completely. Now that I have an Oscilloscope I can see what is wrong with my injector signal (it has two phases, one solid, one 'pulsed', and two peaks, per cycle!!). There are a number of ways to get around this. I can't wait to have MPG feedback too - my MPG keeps going up anyway but it will make such a big difference!

Hockey4mnhs · 03-26-2007, 09:16 PM

wow that looks tight

landspeed · 03-27-2007, 03:44 AM

Drove in today - I think I *may* have sped up down some hills where I usually wouldn't speed up, but I can't say for sure. I have a longer journey tonight where I can coast for long periods (and there is one particular hill where I can drop to 10mph at the top, and get 50mph at a certain point that I know well, so will test it there!). It is a long hill, so the effect if wind resistance should be cumulative down it.

I did notice the engine get warm a lot more quickly with the grille block (and I guess the transmission did too, which should be a good thing). I put the interior heaters on to stop it overheating, but I think having a full grille block and a bin-liner rad block is too much, so the bin liners will come out today!

cfg83 · 03-27-2007, 12:13 PM

landspeed -

Quote:

Originally Posted by landspeed

Drove in today - I think I *may* have sped up down some hills where I usually wouldn't speed up, but I can't say for sure. I have a longer journey tonight where I can coast for long periods (and there is one particular hill where I can drop to 10mph at the top, and get 50mph at a certain point that I know well, so will test it there!). It is a long hill, so the effect if wind resistance should be cumulative down it.

I did notice the engine get warm a lot more quickly with the grille block (and I guess the transmission did too, which should be a good thing). I put the interior heaters on to stop it overheating, but I think having a full grille block and a bin-liner rad block is too much, so the bin liners will come out today!

Do you have an electric radiator fan? If it is controlled by a relay, you can attach a switch to ground that turns the fan on by your command.

cylon.JPG

Here is one example for Saturns :

Manual Radiator Fan Switch
http://www.therob.com/appearance/switch.php

I just did this (pin 86 on my relay) and it gives me that feeling of insurance when it comes to full grill blocks.

CarloSW2

landspeed · 03-27-2007, 03:02 PM

I think I will fit a switch to it pretty soon! I'm probably going to have to cut a hole in the grille block to let enough air through as well. I'm thinking that, once air has entered the grille, most of it will leave under the car. So, If I put a hole in the upper grille block, then air that would flow over the car will instead go under the car (not good), so the hole is going to be in the lower grille block. I'm also going to see if I can make some kind of sliding 'door' so I can adjust the amount of block for different situations (e.g. on my commute to work, the engine is fully warmed up now (in fact, just to the point where the electric fan kicks in). This means it will be warmer on the drive home, while for motorway driving I would want more cooling).

On the hill I was talking about above, I still only got 50mph, but I had to brake from 52 to 40 shortly before it due to a sheep running across the road, so actually my car was quite a bit faster down the hill. I did notice much better coasting when I was driving today - I suppose it will be due to improved aero, but maybe also to the transmission warming up more (as the output shaft always turns, even in neutral with the engine off).

I'm going to have to do more aero mods - they seem to make a big difference (although I will have to wait to fill-up time to see if there is an objective difference).

Bill in Houston · 03-27-2007, 03:23 PM

Quote:

Originally Posted by landspeed

I'm thinking that, once air has entered the grille, most of it will leave under the car. So, If I put a hole in the upper grille block, then air that would flow over the car will instead go under the car (not good), so the hole is going to be in the lower grille block.

I agree with this way of thinking. I think that my top grille block will be a year-round thing. The bottom one will be the one that gets adjusted. Plus, if I remember correctly, my A/C condensor coil is in front of the lower opening, and I do want for it to function very well.

On a separate note, I also want to try to find a way to get some air flow over the battery, since I think that the heat of the engine compartment is the reason they have such short life expectancies down here.

landspeed · 03-28-2007, 12:59 AM

Mmmm. I wonder if I should relocate my battery to the boot / trunk of the car?

brucepick · 03-28-2007, 04:07 AM

Some details please on how you attached the fender skirts?
I want something that can be removed for tire changing.

Your work looks very nice and clean.

I'd like to make skirts - on my car they can cover nearly the complete opening since the tire only protrudes at the very bottom.

landspeed · 03-28-2007, 05:33 AM

Bruckpick : This is my experimental setup. Therefore, I used white duck tape

. My wheel arches are a bit rusty anyway.

During the last summer I will make metal versions and attach them with
screws, so that they can be removed when needed. I actually have a trim panel that can attatch to the top of the wheel arch, and make it the same level as the rest of the bodykit. I could use this as part of the base for the screws, and the other screws could attatch to metal plates I could install just behind the bodykit to stop me having to drill into the bodykit (as it is very rare - only 60 left in the UK, the only place they were used).

brucepick · 03-28-2007, 06:33 AM

Duck tape!?!
I think you're all quacked up!

Anyway, that makes sense.
I could easily use screws to attach a panel to the sheet metal. Maybe a dozen screws per wheel. Of course that would reduce the resale value of my 18-year old, 288K mile car.

To avoid screw holes on the surface sheet metal I could screw a bunch of angle brackets to the inner face of the wheel arch, so the brackets' other legs are even with the body sheet metal. Then screw the skirt panels to those brackets.

Gotta find some coroplast/colorplast around here in the eastern US. Hopefully not too pricey.

Bill in Houston · 03-28-2007, 06:37 AM

Quote:

Originally Posted by brucepick

To avoid screw holes on the surface sheet metal I could screw a bunch of angle brackets to the inner face of the wheel arch, so the brackets' other legs are even with the body sheet metal. Then screw the skirt panels to those brackets.

Gotta find some coroplast/colorplast around here in the eastern US. Hopefully not too pricey.

You can attach angle brackets by putting the screws into the existing holes that are used to attach the fender liner, thereby preserving your resale value. :-)

Coroplast should be about 2 bucks for a 2'x2' sheet, I think? That is what I paid, anyway. It seems like you could get it cheap at a sign company. Or, gather signs after election day...

brucepick · 03-28-2007, 07:49 AM

Anybody used velcro or hot glue for coroplast?