headlight ram air with a twist

[srtthis]

have a grudgerace with a guy at work coming up

so far he's been 13.2@100 mph in a pretty stock GT with gears

its going to be pretty much my 2nd pass down the track in this car. 1 pass on a slick.
running a B cam 1.72's SN95 ported MAF 65mm throttle body thats been smoothed out. exploder intake electric fan 3g conversion leaving off a 2step around 4500rpm. qa1's up front with 14-175's lakewood 50/50's out back with 4cyl springs UPR pro adjustable lower UPR radius arm uppers. torque boxes are welded and boxed. full length subframes. headers offroad H pipe blowmasters with turndowns. anything not needed in the car weight wise is gone... im pretty much going to win if i hook but since this is only my 2nd pass in this car im looking at easy ways to make more power

old trick i know of back in the day was to pull a passanger head light and let more air in. im thinking taking a old head light run a 4inch PVC pipe to the back of it. cut the headlight to make it more of a funnel then a open hole and pull the filter run a hose direct to the MAF. would this be ideal for a street car? not a chance in hell... is my car a 100% street car? no pretty much i want to make sure i win... there is ZERO money on this all for pride... and a track burger

 

[VibrantRedGT]

This picture is taken from 1996 (camera's weren't that great, car was Vibrant Red not pink). I would pull the side marker out to get more / fresher air to the filter when I went to the track. I also did the 4" dyer hose trick (picked up a lot of dirt through there). Seemed removing the side marker (or headlight in your case) will jam air in the air filter. It wouldn't hurt, just don't drive at night.

View attachment 173284

 

[srtthis]

This picture is taken from 1996 (camera's weren't that great, car was Vibrant Red not pink). I would pull the side marker out to get more / fresher air to the filter when I went to the track. I also did the 4" dyer hose trick (picked up a lot of dirt through there). Seemed removing the side marker (or headlight in your case) will jam air in the air filter. It wouldn't hurt, just don't drive at night.

View attachment 173283

yea ive done it with 03 cobra's before just never actually hooked the MAF direct to it with a hose.. that and 94-98 and 99-04 head lights dont have the surface area of a fox light...

 

[VibrantRedGT]

I have connected a 3" dryer tube running from the bottom of the front valance all the way too the MAF (no air filter). It picked up lots and lots of dirt. I guess you could put the hose on before the race to avoid that. At the 1/4 mile track, the run off to slow down was really dirty and it just picked all that crap up. Stuff stuck to the screen, awful. Ran it through the fender out where the air silencer would go down to the valance.

 

[srtthis]

I have connected a 3" dryer tube running from the bottom of the front valance all the way too the MAF (no air filter). It picked up lots and lots of dirt. I guess you could put the hose on before the race to avoid that. At the 1/4 mile track, the run off to slow down was really dirty and it just picked all that crap up. Stuff stuck to the screen, awful. Ran it through the fender out where the air silencer would go down to the valance.

yea i ran something like that on my 95 and i did notice that it picked up lots of dirt also. thats why i was thinking higher up

 

[jrichker]

I have heard that the cowl area where the wiper arms are located is a high pressure area due to the change in airflow up the windshield. It would be interesting to see what a 3" hose connected from a pickup to the MAF would do. It is high enough off the ground to avoid sucking up a lot of dust & dirt.

Remember the faster you go, the more pressure you build up. It is not a 1+1 =2 progression, it will be either a logarithmic or geometric progression

See Race Car Design Tips and Information - Aerodynamics


To test this theory out without seriously cutting up your car, some simple instrumentation can be built.

Building a Manometer: You can use a Manometer to measure pressure of a gas. It could even be used to measure exhaust back pressure.
You need 8' of clear plastic hose with about a 9/16" ID. Cut a piece of lightweight plywood into a 18" x 36" rectangle. Fasten the plastic tubing onto the plywood in a big U shape with pipe strap, duct tape or ty-wraps. When you are done, you should have a 2 ½ -3 foot high U with a little left over. Fill the tubing with enough water so that it is 16”-20” from the bottom of the U to the level of the water. Connect one end of the tube to the hole in the cowl and the other to you homemade water manometer As you drive, the water level will decrease in one side and rise on the other. The amount of rise is an indication of pressure. Divide the number of inches of rise by 2 and you have the number of inches of water pressure if you use the 9/16” tubing. If you use 1 1/8" ID tubing and it is a one for one translation.

View attachment 173225

See http://www.engineeringtoolbox.com/pressure-units-converter-d_569.html for a inches of water to PSI converter

 

[reldla1996]

I cut a 4" by 6" hole in my front bumper cover, below the black "bumper stripe", about where the fog lights would be on a GT car, and custom made a fiberglass tube from there (inside the fender) up to the airbox. I put a screen on the front to keep out leaves and larger debris. With the foot or so rise from the bumper hole to the filter, I've had zero issues with anythng getting in the filter area. I've driven it like this for years without any issue. With it, vacuum drops to near zero with any significant throttle input to speak of, above about 20 mph, indicating the tract is pressurized.

 

[srtthis]

got a few more things to do with it. mainly smooth out the cut in the head light, knock the nubs off. fiberglass the headlight lens to the tube to make more of a funel. should be done next week at the latest since ill be at a race this weekend

 

[VibrantRedGT]

So you built a dummy passenger side headlight? That's pretty damn good. Many need that functional but if you're just racing who cares. Good work.

 

[srtthis]

So you built a dummy passenger side headlight? That's pretty damn good. Many need that functional but if you're just racing who cares. Good work.

pretty much yea... took an old light cut out the back around a 4 inch hole but the hole in the light itself is 3.5" right now its in the car drying so i can pull it out and epoxy the tube in from the back then i will lay fiberglass from the outer lens down into the tube to make more of a funnel since the tube isnt square into the housing. i also had to trim the core support to get the tube through.

once it drys tonight i will put my good light back in it so i can drive around on the street. have a 200 mile road trip on friday to make it in so i need lights... actually i hope not to take it since 200 miles and 4 hours is way past my limit in the car

 

[srtthis]

some stuff has come up between the wedding and everything after the race didnt have much time to dick with it. but i got all the sheets of fiberglass layed to fill the gap between the front of the light and the tube to make a funnel shape and started laying the thicker fiber hairs to make everything nice and smooth. should have the rest of this layed tonight or tomorrow and bust out the die grinders with sanding drum to smooth everything out

 

[srtthis]

when it was 3/4 wrapped in sheet fiberglass

working with fiberglass sucks

 

[srtthis]

i will have new pictures of this posted tonight or tomorrow with it in the car

 

[srtthis]

Still have more to do with it

 

[hoopty5.0]

LOL I hope the 1 hp you get from this is worth 5000 man hours of labor

 

[srtthis]

Haha your not kidding... I honestly don't think if input it on a dyno you'll see anything but going down the track it may help but only one way to find out

 

[jrichker]

Nice work on the headlight scoop...

Get one of your buddies to ride along with you. Find a level stretch of road where you can do some testing. Watch for the wind speed and direction, it can have a definite impact on your test results. Do a pair of runs with and without your mod.

Don't choose a speed range that will make you shift gears, the shift quality & speed will affect your results. Use 2nd or 3rd gear and do a run from 2000 RPM to 5800 RPM. Call out the RPM as it increases and have your buddy record it and the elapsed time. If you have one of those cheap digital watches like I do, a stop watch is built in.

 

[David Pepiton]

I'm thinking this might come in handy for this project:

http://www.summitracing.com/parts/spe-9833

http://www.summitracing.com/parts/spe-9832

 

[srtthis]

who said anything about a filter? i want to shove as much air down the motor as i can get

 

[David Pepiton]

hey just putting the idea out there.