Done driving for the year
 

Its time to put my car away for the winter and reevaluate.

My plans are to tear the engine down and check for detonation and see how the thermal coatings are holding up. If everything looks good I'm going to make a few adjustments and change the prechamber a little.

Then its time to work on my new aero mod. I'm considering making a whole aero cover that will be made of acrylic sheeting. I will bond it together using a product that help design. All the seams will have a bond so it will look like its a one piece shell. I will use 6 attaching points with aluminum brackets to bolt it to the car from the underside. This is where the convertible part will pay off, and was part of my plan when I bought the car. It will have a tilt front hinged that I will use safety pins with a cable to unlock at the rear. Pop the pins and push up on a bracket from the drivers seat to tilt the whole cover forward. So now I can open the doors to get out.;)

I will also be adding a taller 5th gear to accommodate the new aero mods.

The car so far has been a success with a few 70+mpg at 55 to 58mph. Hopefully I can get to my 100mpg mark next year with the new aero mods.

I'm also excited that i might have a chance at testing a new product built by one of our ecomodders on this site. It will help a ton for in town driving. I will let him tell or not.;)

Anyway this should keep me busy for the winter.

Be sure to post pics of your work with aeromods :).

Screw the aeromods, I want pics of the inside of your engine! ;)

This is a preliminary idea of what it will look like. But I will be taking pics of the whole build.



I'll show some pics of a few parts of the engine.LOL

I just want a rundown of the current mods to the engine, and pics of how each one turned out after a few miles on it!

I lied... I care about the aeromods too... :turtle:

Update, well after working out more details on my aeroshell I decided to do a rear only aero mod from the b-pillar back. I just got a killer deal on some .060 acrylic sheeting. I'm going to have an 11* drop from the roof downward past the rear of the car by about three feet.

My question is on the sides I was wondering what the optimum angle should be for a boat-tail?

Everything I've read (not much, admittedly) on vehicle aero suggests that top and sides be 10-13*, I believe.

Bottom, I haven't found any specific references or data other than that which can be found openly on here, but I see that 2-4* seems to be a playfully tossed about number.

EDIT: If you check out Phil's T100(?), you'll notice the aerocap looks as if he cut the rear window from a Stingray and brought it out to it's logical conclusion on top of a tonneau cover.

update on aero
 

I'm doing some mock up. I have the top sheeting at 11 degrees.



This extends out about four feet from the rear of the car. I'm trying to figure out what the angle of the bottom to the top will be? It looks like between 20 and 30 degrees?

How important is the bottoms tail piece angle.

I dont have a protractor or a program available that will approximate an angle, but I can tell you that if you follow a natural curve, you can keep attached flow beyond 12* and make for a shorter tail with a lower end point, which will allow for a shallow bottom tail angle. Think about the shape of long range rifle rounds, and try to approximate it with the top piece.

If you want the air to stay attached on the bottom, 4 deg. is recommended, depending on the usual suspects. If you want downforce, steeper angles are good. Some say that air stays attached past 12, but I've yet to see the tuft testing. On top, my favourite 1st guess is always 15 deg.

Thanks for both your posts.:thumbup:

I'm trying to get this done this weekend (I only get one weekend off every month)so all the advice is very much appreciated.

I just measured the bottom angle up and it came out to be 28 degrees.

If I make the top around 15 degrees the bottom will be close to 15 degrees also. Is this a better way to go then then 11 degrees top with 28 degrees bottom?

Bottom has minimal airflow, I'd worry more about keeping the top attached. 15* may do it for you, though.

Best to set up a test bed type of mod, that you can tweak and test, rather than going all out on the first iteration, just for this type of question.

I do think that 28* on the bottom is way too steep to even think that airflow will stay attached, so it might be OK to break cleanly, rather than try to keep attached flow. I assume the front will have a lowered stagnation point, so there will be less than normal airflow under the car as well, correct?

Yes the front bumper is only 4" off the ground. Plus I'm adding even more front lip so it will sit around 1" off the ground. The side skirts will be around
1" also.

"Yes the front bumper is only 4" off the ground. Plus I'm adding even more front lip so it will sit around 1" off the ground. The side skirts will be around 1" also."

That sounds like a maximum downforce setup. I suppose it might be useful on ice, but it will probably raise rolling resistance.

That would be a nail-biter setup around here... I've seen guys with 3-4" of clearance trash their bottoms out here, and I rode around with about 2" for awhile, but I decided it was just too hard to negotiate every pebble in the road at the correct angle and raised the 'Scort back up.

OK I think I will leave the bottom clearance at 4".

I thought that the idea was to keep as little air from going under the car.;) I was wrong this aero stuff is killing me.LOL

The only time I will need down-force would be at the track and the hill climb.

For the most part it will be used for hopefully 1000 mile road trips across the great western United States. I will be mostly on the Interstate Freeway system but you never know when I have to stop to get food etc. what the roads will be like.

So today I will see what a 15 degree drop roof angle will get me for the bottom rear piece.

Check out the nose of vetter's streamlined bikes - it's curved at the nose to allow some air to still get under the vehicle. Not much, but you need enough flow to fill the space between the car and the road, else you get the same effect as the wake behind the vehicle, which will create downforce by means of a vacuum under the car as the air rushes over and around the vehicle, but not under it to equalize the negative pressure.

No matter what you end up doing, make sure it can be changed without too much frustration, because after you test it, you may reveal a weak point in your design, such as a portion with detached flow or a turbulent vortex.

Hey, you never know. :)

I just looked at his bikes. I think I'll raise it to 5" and start there.

I wish I could do some testing with my setup, but now may engine is apart so I can't drive it.:( But I should have it back running in about a month.

You promised inside the engine pics! Let's have 'em!

I will have a ton of pics at a later date with a thorough write up on my engine design.;)

baited breath...

Update I got a little more work done Saturday.

The aluminum frame work is built for the top piece and the brace work from the deck lid to the top is done.
http://i147.photobucket.com/albums/r...eencoded-2.jpg

Today I'm going to make some patterns for the sides and the back tail section.

The top drops 11-degrees. The bottom piece will come up at 15-degrees.

The sides will come in to the back piece at 12-degrees.

Wanna see more!! That looks cool. What is the material?

I'm interested in hearing about your engine, because I have a 95 Civic EX with the same engine. But I'm trying to sell it. I've gotten up to 50 mpg with the auto trans, but nowhere close to what you're getting.

I started a aero thread because i needed to break it up into two category's.

You can see my aero mods here;
http://ecomodder.com/forum/showthrea...tml#post142600

The engine is a 1.6L D16
It has Suzuki Vitara pistons with Eagle rods.


Stock port
New Skunk2 intake manifold
New Zex Stage 2 cam (59300)
New Supertech valve springs
New Supertech valves
OEM 60mm LS throttle body
New ARP headstuds
New OEM valve seals
New OEM retainers
New OEM valve keepers
New OEM headgasket
New OEM valve cover gaskets
New OEM cam seal

New OEM timing belt
New OEM timing belt tensioner
New OEM alternator belt

D16z6 block
New 75mm YCP vitara pistons
New Eagle rods with big bolts
New ACL main bearings
New ACL rod bearings
New OEM main seal
New OEM oil pan gasket
New OEM water pump
New OEM oil pump
New OEM oil pickup
New OEM main bolts

I'm running a P28 ECU with Neptune RTP management.

Turbo Setup:
Greddy 15G turbo
Greddy cast turbo manifold
Greddy cast elbow
Greddy downpipe
Ebay intercooler
Ebay SSQV BOV
Ebay intercooler piping
Hallman Pro MBC

I'm also running a home built lean burn prechamber. I can run as lean as 25:1

This has been the biggest contributor to my mileage but I max it out and need aero mods big time since my car has crappy Cd of .035

Hopefully I can get the Cd down to .025 or less.

You could cut down you tail by probably 2 feet if you curve it. Just throwin' that out there for ya :P