I wanted to take it off so I get a nice amount of fresh air cooling the intake manifold/intake elbow. Thanks.

 

Very carefully

I used a dremel tool on mine with the flex extension... using cut-off wheel's and the sanding drum...

I also used a pneumatic body-saw, but that's because I was at my brother's shop when we did it..

 

I used a dremel also!!

 

rain baffles???

the ram air holes in the hood are blocked ???


can't be...

 

Someone explain the theory behind removing the baffles.

So everyone thinks that a more direct path is going to create greater HP? Does anyone have any dyno proof of this?

At such low air flow speeds this HP advantage will be unlikely.

 

On a Dyno you would see nothing because #1 your hood would be up and #2 no air is moving over the car. I know on my 97 it completely stock ran a 13.97 @ 100 mphwith nothing but a flowmaster cat-back. I removed the baffles and on a hotter day (approx 8 degrees hotter) I ran a 13.74 @ 102 mph.

 

That's a pretty stout difference. Out of curiousity, would you be able to post the timeslips for comparison? If that's a legit gain, then I've really been holding myself back. 2 tenths and 2 mph is a heck of a gain.

 

I'm sorry I dont have a scanner but I can send a copy of them to you through the mail if you wish.

 

No offense, but I don't believe for a second that was all because of the rain baffles. 1st of the runs wheren't the same day so pressure, temperature (you said it was close), and humidity changed way to much for that to be scientifically significant. Even air quality in terms of O2% can change. Your car cooling off in the staging lanes just a couple of degrees more could account for a lot if not all of that gain. Did you note the wind direction and speed? Heck, you didn't even post the 60' times for comparison.

-brent

 

Ok , let me post the 60 foot times etc. the 1st run was a 2.06 and the second was a 1.98, there is a diff there that could account for maybe 8 or 9 hundredths, its allways windy in Oklahoma so only the direction could matter, and August in Oklahoma is extremely dry and hot. I also know the SOTP meter was quite pleased. Of course wether you beleive me or not is irrelevant to me, I was pretty pleased with the difference.

 

FYI 60 foot doesn't relate direcctly to ET, but those are very close 60'. Your car temperature/heat soak alone could account for most of that, and barometric pressure does change even in oklahoma.

If your happy though, I'm happy nuff said.

 

Actually yes, I do think that greater airflow will be achieved by removing baffles in the airflow path. Second of all, my car is supercharged so I don't use the ram-air, i want the cooling effect.

They don't just clip out or something? I wanted to remove them but not if I can't put them back in when winter comes around...

 

Oh you mean the plastic peices at the openings? Yeah there wont be much of an improvement from that and I beleive they are simply clipped in. I was refering to removing the wall inside the hood.

 

Well the .08 difference in sixty foot times could be as much as .13-.15 up top depending on what you hear, but that doesn't explain the 2 mph difference. I'm sure that there's a little bit to be had by removing the baffles.

There's two baffles in the hood, same direction slant, front one up top and rear one on the bottom. That's two approximately 180* bends that the air has to make to hit the filter, and there's no more than a couple of inches at most between the two baffles, thus causing a greater restriction. Removal of the baffles would allow an almost direct shot through the filter into the throttlebody, so yeah, I could definitely see some kind of gain coming from that.

 

Getting back to the original topic.....

I think the original question refers to the two rain "baffles" that are built into the hood, immediately behind the openings in the scoop. I do not think he is asking about removing the little clip-in plastic grids that cover the openings (nostrils??) in the scoop.

You need to think carefully about how you plan to use the car. My first approach was to take about 1/2" off the bottom of the front baffle. For those who never looked, the front baffle is attached to the upper part of the hood, and forces the air that enters the nostrils to make a 90-degree bend toward the bottom of the opening. When the air hits the bottom (lower surface of the hood), it is forced to make a 180-degree turn, so it is now flowing straight up. That sudden bend forces any entrained drops of water to fall out of the air stream, and impact the bottom of the passage, where there are drain holes that allow the water to drain out near the latch mechanism.

I remove the 1/2" from the front baffle by reaching in with a flex cable on a Dremel, cutoff wheels and sandin drums, as was described above. Be sure to put a lot of masking tape around the nostrils to prevent damaging the paint.

The back "baffle" is actually part of the inner skin of the hood. I just cut about 1" off the top of the rear baffle. Again, a cutoff wheel on the Dremel. Since you can now see the inside of the hood, and my SLP hood was white inside, I painted the inside of the scoop flat black.

The above cuts left a small amount of "overlap" between the front and back baffles. I figured that way, the water would still tned to get knocked down out of the air flow. Driving in a couple of heavy rain storms confirmed this was OK, and no rain got to the filter.

Does this help.... I sereiously doubt you could measure it, so I have to go by my engineering training, and some work I've done analyzing air flow in ducts. Reducing the number or magnitude of the "bend" the air makes will reduce pressure loss.

After my car graduated to "track only" car, I cut the front baffle almost completely out (now I could access it from the back), and took the back baffle down aobut 2" below wher it was originally. Doesn't pay to go any lower than this, since this point is already below the top cover. DO NOT DO THIS ON A STREET CAR. I found that the first tijme I towed the car in the rain, there was water all over the air filter. And that was without the engine even running. Now when I tow, I stuff a Moroso foam rubber intake scoop plug in from behind.

Just to keep "ram air" in perspective..... the gain is the result of "velocity head"... pressure that builds due to the fact the car is pressing into the air stream. But at very best, that effect is only about 1% pressure gain at 100mph... and that's 3HP in a stock LT1. And since a 1/4-mile pass only spends a second or so at 100mph, you will see very little gain in "area under the curve". You aren't going to pick up 2/10'ths with the Ram Air in the first place, no matter how much baffle got cut out... .defies the laws of physics.

Cut baffles, before painting