95 civic drag race car project
 

So after many tries to stay competitive with all the faster car, I started to look at what I may be doing wrong.

Horse power was about the same at others and im not a bad driver either.

So my 2000 honda civic that I been racing the last 5-6 years, I decided to put it aside for now and get a 95 civic h/b.

The new car came with cage and race ready, but I want to take it a step further and make it more aerodynamic so hopefully I can get ahead of the competition.

I looked in the drag coefficient and compared the two cars to see how much power it looses at different speeds. The best I could get my 2000 civic is as low CD as the 95 civic.

Cant' post pics yet, so I have to wait until after the next few posts.

Stefan

Taken in consideration the cars CD and frontal area I made a graph of how much hp a car looses at different mph.

Next step and thats where hopefully everyone here comes in, is to help me decide what mods are the best improving CD in the 95 civic.

Front bumper block off
Rear kammback
Under body full flat panels

Here is what I been testing on my homemade wind tunnel.

Stock spoiler on the 2000 civic h/b

http://ecomodder.com/forum/member-on...ck-spoiler.jpg

Kamm back on the 2000 civic h/b

http://ecomodder.com/forum/member-on...-kamm-back.jpg

And the new race car

http://ecomodder.com/forum/member-on...g-race-car.jpg

And the graph of the cars and hp loss

http://ecomodder.com/forum/member-on...-mph-vs-hp.jpg

Does the car have a smooth belly pan? That would be a very important upgrade to make. You could even secure it with hood pins or something for easy removal.

Just how fast is this car? I noticed the ITB's sticking out of the hood so im guessing its pretty well built.

Car is built, motor makes about 350 whp all motor. In the 2000 civic I ran a 10.7 sec 1/4 mile @ 126 mph. All other cars are running about 130 mph.

Car will have a belly pan all the way, working of the right angle and length of the kamm back. Also thinking of a scoop above the itb's so it will get air from in front of the bumper where there is more air pressure.

Stefan

Damn, nice work on the sub 11 sec.

Kammback here ya go :)

http://i43.tinypic.com/34eyqmf.jpg

from the pic it looks like you got some interior you can still remove. and remover the door glass and replace it with the netting. also what class are you running in so i can look up those rules....

I would also get that front end lower or go get some type of chin spoiler put on like some garden edging.

The way they are now the TBs look like they are in the low pressure area.

Yea front will get a make over as soon as the new engine is in and the suspension height is set.

I was thinking the same thing about the low pressure of the itb's. I was looking at making a scoop that will harness the air pressure from the front of the bumper.

Stefan

NICE results with the 'homemade' windtunnel !
Please share with us how you did this ( in a separate post of course )

I noticed the stock front end, and wanted to suggest a fiberglass front end, since you can get one with flared fenders. Right now, the wheels are sticking out in the breeze and are a major drag.

http://i800.photobucket.com/albums/y...PieceFiber.jpg

The TBs look like they stick up in the breeze. A faired snorkel would clean this up and add HP as well.

I made a few flow dynamic set ups to see what it does. Here are a few results.

Stock form

http://ecomodder.com/forum/member-on...3344-stock.jpg

chin kamm diffuser itb no scoop

http://ecomodder.com/forum/member-on...b-no-scoop.jpg

kamm diffuser itb mid scoop

http://ecomodder.com/forum/member-on...-mid-scoop.jpg

bumper kamm diffuser itb scoop

http://ecomodder.com/forum/member-on...-itb-scoop.jpg

This stuff is cool. I can play with it all day. Same thing with my wind tunnel.

Stefan

Looks like you are on the right track. I'd agree that the ITB hole is in the wrong place. Front and center, down low on the bumper would be better place to arrange a RAM air duct. I really like your wind tunnel! I race my car a couple times every year and am amazed at how much the other guys are leaving on the table in the aero department. I got the quickest ATX ZX2 right now and would like to think all the aero mods I've done is one reason why. You can learn a great deal here about aero.

You should consider the front air dam along with your belly pan. I'd also try to get those front tires shrouded and get moon eye disks on the front wheels and make some rear wheel skirts.

dude put a boat tail on it.....

but with the ITB i would fill in the hole and put an Subaru STi scoop on it. its not to big.

Boat tail idea is no go. I can't extend more than 12" behind the rear of the car.

The subaru scoop is a no go either, its been tried and doesn't work. Its been tried and it slows down the car due to air being limited by the dead area.

Best I could do for it is most likely this :

http://ecomodder.com/forum/member-on...-itb-scoop.jpg

Stefan

Make sure you put a ground plane in there! Right now it's acting as if the car's floating in air. (See how the airflow is going outside the frame? Yeah. Also, try taking the wheels out. After all, the rest of the drawing is the centerline and there are no tires in the center of your car. :thumbup:

Looking good. I'll be watching this project. :cool:

Just read the other post that said to put a ground. I made a new car all black and put a ground.

Stefan

Can you gang all the throttle body inlets into a common inlet plenum and run that into a home made Pro Stock style scoop.These have the lowest drag and are high enough to get up out of the boundary layer.It would probably project a bit ahead of the nose.Is that a rulebook breaker?

These are the rules I have to follow.

ALL MOTOR PRO presented by Competition Clutch

PAYOUTS - $700 - Must have 4 qualifiers for full payout. Less than four qualifiers will receive half the normal payout. Qualifiers must run 13.99 and faster.

Winner - $500
R/U - $200
Semi 1 - $50 - if enough cars for a Quick 8
Semi 1 - $50 - if enough cars for a Quick 8

CLASS SUMMARY
Heads-Up, Pro-tree (.400) class for natuarally aspirated 4/6 cylinder or rotary oem frame import/sport compact vehicles. No restrictions on exhaust. Three qualifying passes permitted.

BODY
Import or domestic compact car bodies allowed. Lexan windows allowed. One piece front ends prohibited. Tail lights and head lights required (one may be removed for induction purposes)

INTERIOR
Doors must open and close from inside and outside the vehicle. No center drive configurations. Dash must remain.

CHASSIS AND SUSPENSION
All vehicles must retain factory chassis. Vehicles must maintain stock drive configuration. Wheelie bars and straight axles prohibited.

ENGINE
Import vehicles may run 4 and 6 cylinder motors, as well as rotary motors. Domestic manufactured vehicles are limited to 4 cylinder engines. Engine manufacture must match chassis manufacture.

POWER ADDERS
No power adders allowed. Power adders include turbochargers, superchargers, and nitrous oxide systems. All nitrous components prohibited even if bottle is not present.

DRIVETRAIN AND TRANSMISSION
FWD or RWD allowed. Stock driveline configuration must remain. Any transmission allowed.

EXHAUST
Any type of exhaust allowed.

TIRES
Any DOT approved tires. Slicks limited to 24.5 x 9.5 for FWD and 26.0 x 10.5 for RWD.


Stefan

body
 

I didn't catch any body mod restrictions.An open door?

onefstek can you please tell me the name of that software?
I already see some people using it but i never catch the name.
What's your time on 1/4 mile?
There's no all motor in my country, all motor must be very competitive, so you need to look for details, one tinny detail, close all gaps in your front even the smallest ones, leave only the ones you really need, use duct tape to close them, check under the car, , close all gaps then too and make it smooth, cut your rear bumper to be far from the ground so the air flows faster(some people drill some big holes on rear bumper).
I used to do that on street racing cars, it actually works a lot at high speeds, i dont know how fast is your car, but if it's fast, you should look at those details, because, faster car, bigger drag.

I have to keep the doors on and windows closed at all times. Drag race NHRA rules are also in effect for our class besides the event rules.

Stefan

In my country theres only this classes:

CLASS 1 - PROType(bikes included, so you can run you car vs a super bike)

CLASS 2 - 4x4 TURBO DIESEL / petrol no LIMIT of engine displacement

CLASS 3 - Petrol TURBO +1500cc > no limit cc

CLASS 4 - petrol TURBO <1500 CC

CLASS 5 - Petrol natural aspirated +1600cc > no limit cc

CLASS 6 - Petrol Natural aspirated DE 1300 ATÉ 1600 CC

CLASS 7 - DIESEL OU T. DIESEL no limit CC

CLASS 8 - Petrol natural aspirated <1300 CC

CLASS 9 - womans - No limits for the girls :D

You can use Nitro, water injection, methanol, propane, etc, wherever you want

I like reading your information. thanks

I been busy removing all four coats of paint from the engine bay the last few days. As soon as that gets done, ill get back to some aero mods.

Im working on a scoop for my ITB's that will not have a bunch of drag.

Stefan

Check the rear of this car:

http://www.youtube.com/watch?v=G5VWo...eature=related

I can tell that this really works on a high speed car

Are you referring to the bumper being cut all the way up?

Stefan

Yes.
I tried this on a turbocharged honda crx(b18 + big turbo) and a slightly more discret version on my dailly golf mk4 tdi, this mod with a lower front and all gaps closed you higher top speed or get there, i also smooth all the under car side and use lightweight magnesium wheels with a very "closed" design for better aerodynamics, i noticed all this mods on my dailly car, i get better fuel economy and the car is faster.
Sorry if i can't make me understand well, i'm not english fluent, sometimes i have some difficulties to express myself :)
I reccommend you to check photos of well builth cars, big winners and big thinkers spend a lot of time looking at details that no one looks, thats why not everybody can be a winner at drag strip, you can use the fuel saver design technology in a drag strip, because fuel savers, save a lot of power, allways remeber that.

http://ll.speedhunters.com/u/f/eagam...456%20copy.jpg


This is a car builth for high speed records, take a look at the duct tape, all gaps are carefully taped.

http://ll.speedhunters.com/u/f/eagam...e/IMG_1070.jpg

http://ll.speedhunters.com/u/f/eagam...e/IMG_1053.jpg

Yea I already have the rear bumper cut and have the holes in it. Im looking at stuff that I may have overlooked. I plan on doing the flat bottom of the car and close front bumper.

I was also just reading about the tire spouts and how much it helps. Every little thing will help above 60mph.

Stefan

Gurney flaps on the front wheel wells might help a bit. I re-read your rules and it never said you couldn't use them. It never said you couldn't boattail behind tires either.

A little update on the car since the race season is getting closer and closer. Engine is almost done.

Car is getting the front bumper closed with sheet metal. Im leaving a little lip up front.

http://ecomodder.com/forum/member-on...ont-bumper.jpg

Soon I will get a chance to tackle the rest of the car.

Stefan

Well I been MIA for the last few months but I been really busy with a new shop, but I also had a little time for the race car.

Ended up reusing the same motor from last year and just refresh it a little bit to do some more testing on the car. We dyno tuned the car and it made about the same hp as the motor last year.

For the most part the set up is the same, with a few exceptions.

Weight is 2050 instead of 2150
Intake manifold instead of ITB's
Under car belly pan
Rear diffuser

Car ran a best of 10.9@ 126 mph.

This year first time out we were in for a surprise. We were expecting the car running a 10.8 or a 10.7 due to being 100 lbs lighter.

Fist run off the trailer car ran a 10.69@127mph.

Through out the day we tested a few different tire pressures and launch techniques and by the end of the day we were able to bring down the time to 10.65 @ 128 mph.

A week later and a few more improvement on the car, including a few more hp from some changes we did on the dyno we were out to another race.

Again first pass off the trailer was to be a surprise. With a very fast car lining up to us I decided to go all out and see what I can do. Car bogged in 1st gear from our 8000 rpm launch down to 4000 rpm where power is very limited. But the car came out ok and on the return road I picked up a slip that was 10.56@130.2 mph.

Not sure what of the changes worked yet, but im assuming that my long search for the aerodynamics of the car had allowed me to run some good times in conjunction with a well set up suspension and a not so bad power from a small motor (my 2.4 vs 2.7l comparing to other faster cars)

So I wanted to thank this forum for being so open about mods that work and willing to help others.

Stefan

thats very good!
You're running N/A engine?

Yes sir car is all motor making about 330 whp.

Stefan

Very nice! i must say, your all motor is faster than some turbo civics in my country :thumbup:
And they strip all the interior(and everything lol).

Thanks guys, I hope to get it a little faster this year on the same motor.

Stefan

Looking at your pictures (didn't read alot of detail) I can see a few more aero improvements.(dont know if they are against the rules)
Boattail the rear of the tires,
Smooth wheel covers,
Side skirts,
And make the splitter a ground scraper(if it isn't already)