sc1 aero mods
 

I want to do something like this:

Before 1998 SATURN SC1


http://farm6.static.flickr.com/5122/...c39618cf_z.jpg

After

http://farm6.static.flickr.com/5123/...7a142a42_z.jpg

After to many

http://farm6.static.flickr.com/5201/...c86380a4_z.jpg

I used drywall screws through the bumper and chassis, hotmelt and wire ties to attach the belly pan and rear wheel skirts. I was watching crs and SUVs driving in the rain on the feeway a few weeks ago. There is a surprising amount of turbulent spray coming out of the front wheel wells. The bigger the gap between the tire and fender, the more spray. I saw a UPS truck that had bristols between the tire and fender, filling the gap. I might try something like that with smooth hub caps.

http://farm6.static.flickr.com/5170/...ac0981b7_z.jpg

The belly pan and skirts have made a difference, the car coasts farther, and I have to use more brake, I am driving faster with less throttle. The car gets up to 70 -75 mph with little effort. I am sure I could get super mileage of I had a kill switch to coast with. It would be really nice now if it had another higher gear. I could try taller tires, but handling would be affected.

I had a belly pan on my old saturn wagon and I could see leaves blowing out in back of the car, the air underneath was actually going back wards! I think the pan in the SC1 might be throwing up debris from the tires, as I don't seem to get s many tailgaters and cars stay a good distance behind, about 10 car lengths.

The right side mirror somehow broke off yesterday and I cut wires off. I can hear less turbulence on that side now. It was previously damaged when I first pushed the car into the garage and it was too far to the right.

Tony

Very, very nice.
Funny - just hours ago, I was thinking about aeromodding this very same car in PhotoShop. :-)
I like the full belly pan, but if this year Saturn is like the previous years model, the car is a ' bottom breather ' and you could completely close off the front end without the car overheating.


That is some heavy duty coroplast. Where did you find it ?

No, just regular 4mm stuff from the sign shop, about $ 23 for a 4x8 ft sheet. The grill is blocked mostly, and in winter it is just a hair above 1/4 hot. There are pictures posted of the rear of the pan. Hotmelt gets brittle in 7F weather and i lost a skirt on the way to work the other day. Now it has screws holding it.

http://farm6.static.flickr.com/5090/...37bc89a0_z.jpg

The black coroplast is about 6 to 7 years old, I took it off the old wagon and reused it on sc1, so its seen at least 6 winters. It didn't hold up so well near the muffler so I put some aluminum sheet there. Under the engine, it sagged and curled up. I had to cut openings to change the oil. I think the rear pan has more effect than the front pan, as I noticed a bigger increase in coasting with the rear on.

You can see the hitch in the photo, it hangs down below the bumper. I would like to raise it up into the bumper.

You can form coroplast with a hot air gun.

My next question was going to be how that you planned to have an exit for the air once it enters the engine compartment . I didn't know you had a full grille block.
Without the block, there wouldnt be anywhere for the trapped air to go ( except maybe out around the wheels which might cause even more turbulence in that area.)

I like the look of the car with the wheel covered. Some cars look odd with wheel skirts, but your car looks cool.
( the EV-1 was marketed through Saturn after all )

I think the stripe helps the looks.

The air exits just before the cat theres about a 3 inch gap between the frames about 3 feet wide.

On the wagon I made a shark gill exit from coroplast.

Cars are fine, but my first love is HPVs

http://farm4.static.flickr.com/3351/...44d96eb0_b.jpg

I like the bristle idea to fill the gap around the front wheel.
Something else you could try would be to create a partial skirt made of flexible rubber that just touches the top of the tire.
As the tire moves up and down over bumps, the skirt would flex.

Yes maybe some TPE cut into strips.

Saturn s series tire sizes
tire size aspect ratio rim diameter tire diameter height (in) ratio mpg change %

175 70 14 23.65 -0.41 1.03 -1.7 %
185 70 14 24.20 -0.14 1.01 -0.6 %
195 60 15 24.21 -0.13 1.01 -0.5 %
185 65 15 24.47 0.00 1.00 0.0 %
155 80 15 24.76 0.15 0.99 0.6 %
185 75 14 24.93 0.23 0.98 0.9 %
195 65 15 24.98 0.26 0.98 1.0 %
165 80 15 25.39 0.46 0.96 1.9 %
195 75 14 25.52 0.52 0.96 2.1 %
195 70 15 25.75 0.64 0.95 2.6 %
185 80 15 26.65 1.09 0.92 4.5 %
205 75 15 27.11 1.32 0.90 5.4 %
195 80 15 27.28 1.41 0.90 5.8 %
215 75 15 27.70 1.61 0.88 6.6 %
225 75 15 28.29 1.91 0.86 7.8 %
215 80 15 28.54 2.04 0.86 8.3 %

if Im seeing this correctly on the belly pan, you run the chance of serious parachuting.
otherwise looks pretty good.

No its screwed down and vented in the rear, grill mostly blocked. I guess there are always armchair critics. It's been on the other car for 6 years. There is a net venturi effect pulling it down, though and the skirts get pull out, because one side rubs at low speeds and not highway speeds.

I changed out the front wheels, 40 psi cold.

185/65R15 vs 165/80R15 (165R15)
http://farm6.static.flickr.com/5290/...8d7054ef_z.jpg

The 165/80R15 tires give 70mph on the GPS at 65 mph on the speedometer or 7.7% increase. The car seems to slow up hill, but considering a head wind and 450 lb weight of passengers, not too bad. You defiantly want to drive slower with the skinny tires, since the car doesn't handle as well as the 185/65R15 tires. It seems to coast really far, though. Almost down to 1/4 tank.

15 minute grill block. Note skinny aero tires and forward located headlights. I am hoping to break 40 mpg this fill up.

http://farm6.static.flickr.com/5241/...dfc104d139.jpg

http://farm6.static.flickr.com/5129/...ce4998e8_z.jpg

Before image:

http://imganuncios.mitula.net/1997_s...a_11477940.jpg

When we mentioned the parachuting effect, it's not trying to be critical - merely suggestive.

I really like the look of your new grille block. It reminds me of the GM Impact.
( And the symmetry is nice as well )

http://www.wired.com/autopia/wp-cont..._-GM_sized.jpg

Cd -

Yeah, and another thing to keep in mind is that we are not only talking to the person we directly address in the post. We are also talking to the lurker that may be reading the thread and considering the mod. In that case it helps to mention the pitfalls, even if it's redundant in relation to threads that have already attempted similar mods.

CarloSW2

Pitfalls, like the temp going up in stopped traffic in warmer weather.

Cool image CD, I saw an Insight on the interstate today and it had the mirrors mounted way out on pylons also.

I let my wife drive the sc1 home today, she said it doesn't slow down when you put the clutch in, it just keeps going. I guess she had to break a little harder than normal. She must have been going down a slight grade.

My next mod will be front fender skirts, I bought 4x8ft x 1/16 thick pvc plastic shower sheet for $15 from Menards. I'll rivet on 1/2 of a 700c bike rim for reinforcement, maybe bungie cords to keep it tight against the fender and a hinge at the top.

Bought a new vehicle today, 1991 Honda crx hf for $500. needs some work, should get super mpg.

The Impact back looks cool too:
http://www.carstyling.ru/Static/SIMG...32D52BB36DA89D

Yes, the Impact looked so much better that the EV-1 after it. It's like GM tried to de-style and uglify the car for some reason.
Little subtle style elements like the shape of the front turn signal lights, as well as the rear styling of the car never made it with the EV-1. The character line on the back end of the car above the tail lights really made the back of the Impact more attractive than the EV-1, and the way that the tail lights met up with the body line made the car appear less bulbous. Even the body colored roof looked better than the blacked out version on the EV-1 which seemed to emphasize the jelly bean look.
The bumper opening even looks good on the Impact versus the EV-1 bumper which ended up looking like a pair of swollen lips.
Personally, i love the look of the Impact.

Congrats on the CRX. I certainly jealous !

Oh look at this:
http://farm5.static.flickr.com/4088/...b94ecafb_b.jpg

arcosine -

Oh yeah, we have talked about that before, but that might be a better side view than we have seen. I'll wait for aerohead to chime in.

Here's another picture from one of aerohead's albums :

Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com - aerohead's Album: Other vehicles 1

http://ecomodder.com/forum/member-ae...-duct-tape.jpg
CarloSW2

I found that foam weatherstripping gasket works really well to seal up the hood gap.

Ive got the sticky sided foam on the front of the hood and around the lights.

There are those swollen lips that I was talking about ( the front end of the EV-1 ) :p

Have you guys noticed how much that the 'tail on that EV-1 goes upwards ?

You can see it from the side of the car, but it is also even clearer on the 3/4 front picture.
If you follow the trunkline on the side shot of the car you can see how there is a definite upwards rise to the 'tail.

About the Saturn, you are lucky because your tires don't protrude much. You will be able to have some pretty flush skirts.

I didn't notice if your SC1 is a stick or auto.
IDK why you shouldn't be up past 40mpg already; the SOHC S cars w/ 5speed were rated for 40mpg stock, and I've read of lots of guys beating that. I had a '93 SC1 w/ a DOHC swap that I was able to get 36mpg in, mostly 32-34 w/o trying.
you might be running too cool also if your temp gauge is only at 1/4. do you have the brass ECTS in there? saturns should be running at 1/2 gauge.
I would suggest lowering springs and try to fit those 80series tires. I don't see why 45+mpg wouldn't be attainable.

mpvue -

It's a stick. I clicked on the his car's name and it took me to the garage for his sc1. The brass ECTS are a must. I would guess it already has that. I also have a 192-195 degrees F Coolant Thermostat (Napa Part #THM268)

CarloSW2

In case you haven't noticed it's winter outside in the teens, 39 mpg is what GM claims for highway mpg, probably at 55 mph, not mixed driving in winter temps and 75 mph highway speeds. Sure I could hypermill but thats a pain. You can also view the fuel log and then I wouldn't need to explain.

My stock 93 SW2 got 36 mpg and you did all that work and only got 32-34? 3 previous Saturns all ran at 1/4 gauge stock temp.

No lowering springs man.

If you want a higher temp thermostat than 195 you can take the center pin out and grind it shorter. This will make it open at a hotter temp. I suggest using a thermometer to calibrate it in hot water on the stove, when your wife isn't home.

yeah, winter here too.
I remember seeing 40mpg on the window stickers when I was selling saturns in '02; the twin cam cars got 36mpg hwy.
my '93 SC1 had a '94 twin cam swap and a '92 header and a SPS exhaust and I hardly drove it gently, so my numbers are real world. I could get 36 if I was careful, and that's what they were rated for.
as for the temp, I have seen lots of S cars run at 1/4, but IMO they run better at 1/2 temp. if the ECTS is cracked or the wire is corroded, it might not give correct readings.
don't know why you wouldn't want lowering springs. S cars sit too high and could benefit from an 1" or so lower IMO.
regardless, I like what you're doing.

sc1 mpg was 39 for 1998 for some reason 40 all other years.

Yes I had the headers also on the 93 SW2 and 2 inch exhaust.. Had TotalSeal gapless rings. Had a diode on the MAP sensor to advance timing at low rpm. Other than that it was stock. It had some go compared to singe cam saturns. Diode didn't seem to help on sw1, haven't tried it on sc1.

I added a low drag antenna to sc1....


http://farm6.static.flickr.com/5083/...defa2967_z.jpg

for foxhunting...

HOMING IN -- Radio Direction Finding (Radio Foxhunting, Transmitter Hunting, ARDF) for Amateur Radio and Public Service

I made a front skirt and tried it out, the wind ripped it off the first time I hit 55 mph. I was able to retrieve it. The rivets pulled out of the poly tube and the bungie cords pulled through the holes. Thinking of a better design.

arcosine -

That's the inventor's life. I like zipties where applicable because they're solid and quick-cut-removable.

What is the brand/model of antenna? I can't glean it from the URL you posted.

CarloSW2

I've always thought the SC's would be sweet to aero mod.

Smooth wheels helps a lot, especially on the front since the wheels are not (easily) covered like the rears. My Scion xA has larger than normal wheel openings, but doing this sort of skirt might also help on other cars:

http://img.photobucket.com/albums/v7...d/DSC_3666.jpg

Antenna is a home made (and designed, on NEC) 2 meter, 3 element x 2 broadside beam, > 10 dBd gain at 5 feet above the car. (rubber neck attractor) I will be painted black and used primarily in the dark.

Neil, That looks good, I was thinking of something like that but haven't worked out how to fill the gap behind the tire without it catching the air. I have screwed in 1 1/2 inch black poly tubing around the opening which I formed into an arc in the oven using a bicycle rim. (pictures later). My current thoughts would extend the fixed part over the whole wheel well with circular slots cut 2/3 around and something elastic for tension, but maybe the top hinge is the way to go. I think that the Bonneville wheel covers won't attach to the aluminum wheels.



.

I was trying to mimic the original Insight -- fix what you can, I say.

You can use foil tape to cover allow wheels, to make them smoother. Blocking the holes is key.

arcosine -

Thanks for the antenna info. That's an Arcosine-1.0, ha ha.

That's been my problem for years. I finally solved it here :

http://ecomodder.com/forum/showthrea...isk-11838.html

However, that thread is out of date. I have since simplified the parts and moved to alimuinum wheel covers. This pan has a slight gap, maybe < 1/2" :

http://ecomodder.com/forum/member-cf...-cover-gap.jpg

I will publish a new thread with all the details.

CarloSW2

http://www.carstyling.ru/Static/SIMG...94A23753312969

http://www.carstyling.ru/Static/SIMG...38A43CBA8DAF80

"The GM Aero 2000, one of the most aerodynamic automobiles ever developed, was unveiled in 1982 at the Epcot Center World of Design display. The experimental four-seater featured sliding doors, front wheel skirts top-hinged for access to wheels and tires, and a speed-regulated rear foil to reduce fuel-costly air turbulence. Many of the design concepts are evident in GM's electric car, EV1."

The hub caps look like pie plates to me...top hinged it is...

It has a 3 cylinder TDI engine...


The difference between style and aerodynamics is aerodynamics never go out of style, cool a pop out boat tail...

Tony

http://1.bp.blogspot.com/_jv-dS4NpxP...Photograph.jpg

http://1.bp.blogspot.com/_jv-dS4NpxP...2000+Specs.jpg

http://www.lostepcot.com/images/transaeroskeleton.jpg

http://www.lostepcot.com/images/transaerocar.jpg

http://www.lostepcot.com/images/worldcarshowcase.jpg

http://books.google.com/books?id=75d...202000&f=false

This one has a longer tail:

http://deansgarage.com/wp-content/ga...hcenter650.jpg

I'd buy an SC1 and re-body it into that.

TOWMBO however, would disagree.

I put a front wheel skirt on one side and It hasn't blown off yet:


Poly tubing ready for baking at 220 for 15 minutes:
http://farm6.static.flickr.com/5248/...d273bff2_z.jpg

Poly tube formed attachment screwed into inner fender:
http://farm6.static.flickr.com/5084/...aa06bba5_z.jpg

Wheel skirt mounted on fender:
http://farm6.static.flickr.com/5209/...7e5fe3dc_z.jpg

I used 4 cable ties on top around the poly tube and a bungie cord on both lower corners to pull it in. I can hear it rubbing the tire sometimes. I think a spacer pushing at the wheel center would help.

arcosine -

A picture of the whole car with the front wheel skirt would be great!

CarloSW2

Maybe this afternoon I can get a picture with road grit streamlines.