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i have the stock air cleaner on the car right now and the stock flat hood, IMO the stock air cleaner looks hideous with the plastic crap running to the front of the car, but im thinking with the stock flat hood, an open element air cleaner right on the tbi would hinder peformance purely sucking in hot engine air, i would be forced to think the only way to make use of an open element and gain from it would be cowl or ram air no?
Open element all the way. Far superior than stock even with some hot air. The stock one heats up with the thermac anyway and closes the air off until hot. Its one of the cheapest and easiest mods. You can hear and feel the difference.
if you had to choose between enough air or lack of air you take enough air. cold air is a bonus. a lot of people have made cold air induction setups. thier are a lot of threads on here about that use the search feature and you'll see some creative setups.
i was thinking of the open element, then cutting the stock hood and mounting in the trans am and gta style front hood vents for functional air flow...?
I found a single snorkle CAI by a brand called Spectre that worked out great for me. I custom made my CAI from thier parts and it works great, I have it running from the carb to behind the left head light, capped with a K&N cone filter and it gave noticable power gains.
I found a single snorkle CAI by a brand called Spectre that worked out great for me. I custom made my CAI from thier parts and it works great, I have it running from the carb to behind the left head light, capped with a K&N cone filter and it gave noticable power gains.
bahahah all i did was take the spectre filter and attach it to the stock routing.
i figured its sitting in the same spot. so no hotter air than before. looks cool. i took out that little plate that mounts my charcoal canister and filter box. then secured the charcoal canister to the metal under that. (to allow room for filter as it is bigger than the box)
wish i had pics.
but def recommend open element. gta hood vents are only open to inside of hood not underside, but thats my next endeavor making the GTA hood (more)functional. actually been done too. and yes there is a thread on it...
Last edited by jordanandrewkay; 10-22-2010 at 02:38 AM.
Reason: TBI not TPI (SAME RESULT LMAO)
yeah thats what i mean, taking my stock flat hood, cutting it out for the gta vents, maybe a touch farther up the hood so they supply cool air to the element. i see water intrusion being an issue at highway speeds but then again the car doesnt drive in rain unless i get stuck in it
see i have always wondered about that (water) with 4th gen T/A's i have never really studied one. but the guy that cut out his framing under the vents IIRC just used a 4th gen Ram Air filter box and ran routing to his TB. (TPI, but same general idea)
and ditto about the water thing....but i seem to get caught in it alot lol. then again it can be sunny here then drive into houston (bout 30 min south) and it be pouring...so better safe than sorry.
I am currently using a 1975 Corvette lid and air filter 3-1/2" tall on my '88 Formula TBI. Fits under the hood, and sounds great! The stock air filter (2-1/2" tall) seems a little restrictive.
The stock one heats up with the thermac anyway and closes the air off until hot.
Vacuum-powered Thermac? Spring/Summer/Fall, pull the vacuum hose off the snorkel, plug the hose so there's no vacuum leak. Reconnect for winter or trips to cold weather, to reduce throttle icing.
Plumb an air cleaner restriction indicator into the clean side of the air filter. Run the engine at WFO/max RPM. See if there's a lack of air to the carb. Better than guessing. Restriction indicators can be had new from Amazon, or at any junkyard that has Diesel pickups, or '96-newer "Vortec" trucks, or any of the other dozens of vehicles so equipped.
Every "cold air intake" as designed by GM/Ford/Chrysler/AMC that uses "Cowl Induction" or various designs of hood-scoops including the Shaker hoods on Pontiacs, Fords, and Mopars have seals that prevent bleeding "cold" air into the engine compartment, while also having drains to eliminate rainwater/melting snow. They're set up to provide "cold" air often at somewhat higher pressure to the air cleaner ONLY.
D-I-Y yahoos cut a hole in the hood often in a low-pressure area that pulls air OUT of the engine compartment (but it makes more noise, so it's gotta be better...right?) or they wreck the paper filter element with rainwater/road splash (Gotta get a K&N...) or they have enough sense to pull air from a high-pressure area, but flood the entire engine compartment with it which reduces airflow through the radiator.
Take a lesson from the REAL engineers on how to do "cold air induction" properly.
STARTING with looking at how it's already set-up on your vehicle; and the vehicles with optional cold-air packages from the '60s and '70s.
The OEM air cleaner isn't visibly ugly if you SHUT THE HOOD. Are you modifying the air cleaner because you want more power, or because you want to impress someone at the Dairy Queen on Cruise Night?
OR, if you don't like the looks of your air cleaner, just go to the junk yard and grab any one of a number of late model, sexy, large plastic slabs of "engine covers". You know; the ones that don't look at all like engines, cover the stuff we WANT to see (the parts that make it all work), and some times, even saw through vacuum lines causing leaks. Don't forget that they also hold in heat, and make working on the engine more difficult. Don't limit yourself to "Chevy" branded plastic slabs, either! You could get some major upgrades for only a few bucks! Cadillac, POL-sha, Jaguar, Land Rover....BMW, Lincoln....all make big, dumb slabs of plastic, too! It's the fast/easy way to solve an "engine appearance issue"!
The next video in that series is one of several reasons folks need air cleaners.
The four Q-jets are on an isolated-runner manifold, with huge amounts of reversion. The cloud of fuel vapor above the carb "should" be contained with a tall air cleaner housing so the fuel isn't blown around the Earth creating HC pollution. But then the carb jetting/metering valves would need to be leaned-out because the air is pulling fuel when it goes down the carb, when it's pushed back up the carb, and then when it goes back down again.
The ideal situation would be to not use an air-valve carb on an IR manifold. The air valves are quivering like they're having an orgasm. Some severe damping of the air valves MIGHT help.
I loved those Quadrajet Madness videos. Watched all I could find back in the day and I think they had a website too.
Love the idea of 4 Q-jets in full song. Don't know if they ever got it to work right. If they could get all 4 Q-jets to run like dude's one Q-jet does on his 400 Pontiac they would be in business.
Except even in 40F ambients I was seeing 140F IATs stopped at a traffic light or in traffic. In summer you will be getting ~200F air. Especially running headers the air in the engine compartment is absolutely oven like in summer at a stop or lower speeds. You want a sealed filter with air intake outside of the engine compartment. On my TBI car, I used a Cadillac bonnet and a TPI airbox with the baffles cut out and scoops under the filters. On my 87 G20, I put the stock TBI air cleaner and ducting back on mine after seeing those 140F IATs in 40F weather. A couple of days ago I was able to snag the absolutely massive G30 van 454 TBI ducting and a lid for the 5" tall filter used on the 80s square body trucks. I also made an interesting discovery after installing my a/c condenser pusher fan setup. The air duct pulls air from between the condenser and radiator. Idling in traffic with the a/c on my IATs dropped a solid 20F from where they were running. It was 103F a couple of days ago while I was testing the pusher fans operation and effect on a/c pressures as well as optimizing the ac charge. The engine ran for an hour while stationary. I never even saw 120F IATs.
I have also seen guys use the Grand Cherokee 5.2/5.9L air hat to use the TPI air cleaner on a TBI car. The later speed density V6 and V8 air cleaners have a larger opening where the MAF resided on mass air cars. The picture was actually a carbureted car, but TBI units use the same 5-1/8" air cleaner flange. I have also seen the low profile Spectre elbows used as well that have a 4" duct opening.
Stock TBI setup with the thermac deleted and the hot air tube blocked off this is what I was seeing after the engine ran for an hour in 103F ambient temperature. It was 117F.
Stock TBI setup with the thermac deleted and the hot air tube blocked off this is what I was seeing after the engine ran for an hour in 103F ambient temperature. It was 117F. That being said the ~400 hp L31 in this pulls 2 in/hg vacuum at 5,000 rpm with the small block TBI air cleaner and ducting thus my change to the 454 setup. Even with the restrictive small TBI air cleaner it is still making decent power though. That was a 1st gear pull from 0-60 brake torquing against the stock TH400 torque converter. TH400/3.08 gear.
The intake vacuum builds as the engine revs out and the larger 454 air intake will prevent that from happening.
https://youtu.be/UjEKGehu1M8?si=aDY6dAzBGdDfjIKl
You want a sealed filter with air intake outside of the engine compartment.
Exactly right...and exactly like the GM-engineered air cleaner system (already on his car) that isn't sexy enough for him.
It would be worth his time to verify that it works like it's supposed to--the thermac diaphragm isn't leaking, the air valve actually moves, the hot-air and "cold"-air hoses are in place and connected, the air filter isn't plugged, etc., and then disable the thermac for warm-weather use as described above.
Exactly right...and exactly like the GM-engineered air cleaner system (already on his car) that isn't sexy enough for him.
It would be worth his time to verify that it works like it's supposed to--the thermac diaphragm isn't leaking, the air valve actually moves, the hot-air and "cold"-air hoses are in place and connected, the air filter isn't plugged, etc., and then disable the thermac for warm-weather use as described above.
They are hard to find now, especially the ducting, but the L82 Corvette and L69 Camaro dual snorkels are a nice upgrade.
...or get an additional air cleaner and "cold" air ducting from any Treasure Yard, then graft that snorkel and ducting onto the air cleaner he has--a home-made dual-snorkel unit.
Dude doesn't want the ugly snorkels, ducting, and scoops. He wants the clean look of a open element air cleaner but realizes ingesting super heated under hood air is not a great idea.
The closest idea that I can come up with without putting a much time & effort into it is...
A GMT400 truck air cleaner assembly like from a L05 5.7L TBI engine rotated 90 degrees from its normal orientation in the truck so that it faces the cowl of the car's body where the car's HVAC system ingests air. Right in the area where the MAP sensor is on a V8 TBI 3rd gen. Where the fender to cowl Pencil Brace attaches to the cowl pinch weld on a Camaro or Firebird that is equipped with a Pencil Brace.
This cowl plenum ducted air cleaner setup will allow for a clean looking air cleaner system. Will ingest much cooler outside air, will be in a high pressure area at speeds above 35 MPH.
The almost 1 inch taller air filter and air cleaner lid off a GMT400 truck will fit on the air cleaner housing of a 3rd gen TBI F-body. If you want to dress it up a little K&N makes a chrome air cleaner lid kit for the GMT400 truck that comes with the taller K&N air filter.
If a guy has metal working, welding, and finishing skills he can make something that looks great and functions great.
Dude doesn't want the ugly snorkels, ducting, and scoops. He wants the clean look of a open element air cleaner but realizes ingesting super heated under hood air is not a great idea.
The closest idea that I can come up with without putting a much time & effort into it is...
A GMT400 truck air cleaner assembly like from a L05 5.7L TBI engine rotated 90 degrees from its normal orientation in the truck so that it faces the cowl of the car's body where the car's HVAC system ingests air. Right in the area where the MAP sensor is on a V8 TBI 3rd gen. Where the fender to cowl Pencil Brace attaches to the cowl pinch weld on a Camaro or Firebird that is equipped with a Pencil Brace.
The almost 1 inch taller air filter and air cleaner lid off a GMT400 truck will fit on the air cleaner housing of a 3rd gen TBI air cleaner housing. If you want to dress it up a little K&N makes a chrome air cleaner lid kit for the GMT400 truck that comes with the taller K&N air filter.
If a guy has metal working, welding, and finishing skills he can make something that looks great and functions great.
GMT400 truck air cleaner assembly.
The TBI S10s, Astro vans and fullsize vans have one that is opposite of the fullsize truck. I have used one to build a dual snorkel for a GMT400 truck with tubes to both inner fenders. He could have dual rear facing snorkels into the cowl with a little fabrication. Also as mentioned the 454s have a HUGE snorkel on them.
I edited my reply above to show with pictures what my idea would look like in general.
@Fast355 A dual snorkel cowl induction system would have the driver side snorkel running into the busy area by the wiper motor and other stuff.
A guy going to have to have some metal fabrication skills to pull this off.
No way I would use the hot air stove piped to the Thermac system on the air cleaner snorkel with the shared air plenum with the car's HVAC system. Not worth the risk of exhaust gas leak allowing CO and CO2 into the passenger cabin. Probably wouldn't fit anyways.
I edited my reply above to show with pictures what my idea would look like in general.
@Fast355 A dual snorkel cowl induction system would have the driver side snorkel running into the busy area by the wiper motor and other stuff.
A guy going to have to have some metal fabrication skills to pull this off.
No way I would use the hot air stove piped to the Thermac system on the air cleaner snorkel with the shared air plenum with the car's HVAC system. Not worth the risk of exhaust gas leak allowing CO and CO2 into the passenger cabin. Probably wouldn't fit anyways.
Most of the heavy duty trucks do not have the thermac stuff. The 454 air cleaner base I have did not have it to start with nor did my factory GM built 8-lug 2500 1998 Vortec 350 TBI suburban I owned.
The "Power Bowl" you are talking about on the 5 inch tall air filter 454 TBI air cleaner assembly is it on the base or the lid?
Also remember we are talking 3rd gen F-body here not GMT400 Truck and Vans. We don't have hood clearance for a 5 inch tall air cleaner.
On my Firebird with the stock TBI air cleaner base and the taller GMT400 LO5 TBI air filter and lid there is sufficient hood clearance and a Camaro would have somewhat more with its higher hood line.
The "Power Bowl" you are talking about on the 5 inch tall air filter 454 TBI air cleaner assembly is it on the base or the lid?
Also remember we are talking 3rd gen F-body here not GMT400 Truck and Vans. We don't have hood clearance for a 5 inch tall air cleaner.
On my Firebird with the stock TBI air cleaner base and the taller GMT400 LO5 TBI air filter and lid there is sufficient hood clearance and a Camaro would have somewhat more with its higher hood line.
Powerbowl is in the base. 5" lid is a squeeze as well for me.
10-21-2010, 09:50 AM
