Good video Andy. I dyno'd plenty of cars that had exhaust upgrades done on them. Never saw a decent gain unless it was the last of many modifications. The thing that I learnt from that was until an exhaust becomes restrictive, it's not. You can't solve a problem that isn't there. The only gains you can get in an unrestricted exhaust, is from improving the cylinder scavenging, which is all dictated by what is happening in the front section of the exhaust. But you already know all of that. Looking forward to your future videos. Regards Greg

I've got a 2000 Grand Marquis. So far I've snagged and installed a Trick Flow upper plenum and ADTR ziptube. Throttle response is amazing! Next is installing the 2009 CVPI airbox I picked up for $35, a 90mm MAF sensor and a dual exhaust when I can afford it all with a SCT tuner from Marty's Spped Shop. Next year I'll be, rebuilding the bottom end the Manley way (crank, rods and 18cc Street Masters) and adding Trick Flow heads. Bad news is, as a mechanic, I'm a decent woodworker. Good news is, I've got a friend with a 2000 Crown Vic who's teachinng me as we work on each other's cars..

K&N made a cold air system that boxed in the air filter and made it draw thru the headlight...actually works...ask the man who owns one...most important mod for the vic/marquis is at least a 3.73 gear...with a posi...and a free flowing dual exhaust...if you check the size of the tailpipes in the stock ford exhaust it's choked down to like 1 1/2 in the bends over the rear axle...

Yeah man! That's the best secret trick. Cutting the airbox gives the best breathing improvement for free. Definitely worth it. Screwing around with the exhaust is a waste of time and you won't like it.

My testing with removing the silencer on the air boxes I get better throttle response with it on there

Regarding your Ford Crown Victoria, If I were you, I would try to imitate the Crown Vic Police interceptor calibration. You already have the dual exhaust. The next step would be to change your axle ratio to 3.27 or 3,55 . Then, substitute the powertrain control module from a Crown Vic police interceptor. This may require the installation of matching fuel injectors. Replace the MAF sensor and air cleaner assy with one from the police interceptor. The Crown Victoria police interceptor also uses a lhigher stall speed torque convertor, so you may want to change that as well. I spent more than 40 years working at Ford Dealers. Would like to talk to you about this sometime.

Great stuff Andy! Looking forward to this series of videos and applying more mods to our 2011 P71 👍

I used to dislike those cars but they have grown on me. I'd like a black one with a coyote

I enjoyed the testing and I will stay tuned sir

Great video Andy, I did that on my Lincoln town car the air snorkel was so small in diameter it be like us trying to breath through a straw. Tho on the Lincoln they pull air from in front of the wheel well. So I opened up the bottom area more. You could go one step better on your air box and get some of the self stick sealing foam from one of those home improvement stores and completely isolate the air intake from the engine bay.

Son's 97 f150, shaped a piece of 3 in PVC pipe thru fenderwell , picked-up and swapped out intake elbow for PVC, this also helped.

Andy, Go with the OEM intake manifold. Install a 04 and up CVPI air box, intake tube and a 80 mm (Mercury Marauder if you can find one) mass air flow sensor. You will need a tune to make it work. I did my 03 Sport LX 15 years ago and it made a big difference. On the Michigan State Police test, the 04 CVPI (250 hp) ran .6 seconds quicker to 100 mph over the 03 CVPI. The factory exhaust system is actually quite efficient since they redesigned the mufflers back in 1992. The higher numerical RAR will improve acceleration, but you will have vibration from the driveshaft at the end of the 1/4 mile if you are at 90 plus mph.

Always do enjoy your video, off to the family reunion. TTYL

Okay so as far as the airbox goes; the Maurader and 05½+ CVPI airbox supports just over 500 horsepower. There's no need for any of those trash aftermarket intakes, unless you just want more whooshy noises. Last I checked; ADTRs Rocket Couch is still using it. The best and basically only worth while mods, other than opening the box up, is a straighter zip tube and heat protection. All factory air boxes are cold air intakes, aftermarket ones aren't magic and make the air colder. The problem with the Doorman intake is; it's a NPI that's poorly cast. The FRPP intake is just a PI intake. The main failure point of either is the coolant crossover tube. You can get an 80mm throttlebody from Mustangs and Econolines, possibly Mark VIIIs and Continentals, too. If you have DBW, I believe it's Econolines and Expeditions- I forget. At some point you might as well get a CVPI computer because enough of these mods will require a tune to work right. Quite a few things will need a tune, like changing the axle ratio. Also Civvys, exc the LX Sport have single exhaust. The LX Sport has resonators, the CVPI does not. Neither does the Maurader. The CVPI also has stainless steel exhaust. A Civvy might, MIGHT be able to use a CVPI aluminum or metal matrix driveshaft. If I recall; only the CVPI, Town Car and Maurader use the long tailshaft 4R, so it is shorter- as far as Panthers go. I do know the F150 also used the long tailshaft 4R.

I would think having David in the car would be good for 40 horse at least! lol! thanks Andy...

Casper is also a work bench!!! Great stuff and FUN stuff Andy !!!

The most effective basic mods for any Panther car are gears and a tune. Specifically 3.73's or 4.10's and a custom Tune by Marty Ochs of Mo's Speed Shop in Dallas, GA. Neither really increases power output BUT combined those two things really wake the car up and make it much more fun to drive. Anything, and I do mean anything, other than those two things would be a waste of your time and money. The only exception MIGHT be a 03+ P71 airbox and zip tube as well as a P71-style dual exhaust (for cars that don't already have those), but even that is probably negligible.

Im really loving this, i have a stock 98 npi mustang gt, i want to get some more performance out of it. So keep it coming, great job Andy!

Andy your videos are great. You speak very well on camera

Always do my friend I usually get hooked up to the end everytime.

I honestly thought the cat deleted would have picked up some power 😢 air induction looks a good improvement, thanks for sharing, all the best to you and your loved ones

Port the throttle body elbow for a solid 10 hp gain. Might as well port the throttle body too.

I noticed the intake as well. I bought an e-bay intake for my P71 and it worked great. I bought another E-bay intake and put it on my other P71 and I lost power above. It fell on its face above about 4 grand. I noticed the runners were flatter on the second one I had bought. The first one I bought had taller runners similar to the original Ford intake. They were both $135.00. I went and bought a factory Ford P71 intake and haven't had a prob since. But it was $315.00 lol. Big difference. The E-Bay intakes seem to last me about 2 years before they have to be replaced. It evens out in the long run. When I replace the E-bay intake on my first P71 I will just go to Ford and get an original. Longevity is also a concern.

I put that same tube without the resonator boxes on my Lincoln and a high flow filter and it definitely has a lot more roar under load

Good info, I'm going to take the fallopian tube crown vic 😂😂😂

You can use HVAC ARMOR FLEX to seal the air box to the radiator support

I have an ‘01 CV HPP. It was regularly faster than the later “250hp” CVPI models and I hardly did anything to it. Airbox was modified like in this video(but not opened as much), K&N filter, I ported the upper plenum, “opened up” rear cats, cheap-o turbo mufflers and resonator delete, stock 3.27 gears but with a trac-lok with the +1 clutch mod and a Jmod on kill…never could get it to hit hard on the 2-3 but almost always barked the tires on WOT 1-2 shift. Bought it with 100k miles and beat it every day, twice a day, to and from work…and basically any other time I drove it…finally tossed the chains at 178k. RIP

Kia forte's have a very restricted intake tract and he made a 4 inch inlet out of drier duct to the airbox from a opening in the bumper. He said that the fuel economy went way up. Performance stayed similar. He kept the mod because it was cheaper to drive.

Andy I just got this video here and let me tell you it was very interesting and informative for me, thank you for your time. And I got a question. I got an 07 town car signature limited, I got a set of mufflers from a 15 mustang GT that I've been wanting to install, I don't want it to be loud and annoying, I just want to be able to hear some when I get on the freeway , do you think it'll be to loud or should I just delete the rear cats. Thanks again brother.

I'm confused, how can removing a restriction (stock muffler) in the exhaust system result in loosing HP? It doesn't make sense, replacing a muffler with a piece of pipe will result in less back pressure, and less back pressure should result in a HP gain or at least keeping the same HP it had with the muffler. There has got to be some other variable that caused the drop in HP.

The intake manifold comparison could be a red herring. There were several versions of the intake manifold. There was a recall for coolant leaks and some other issues. The various intake mods that use Mustang parts will improve the performance in small steps. An extrude honed Ford Perfomance/Motorsport version of the Police Interceptor intake historically makes a huge improvement after the air intake tract upgrades. Gets closer to a Marauder

when you did these tests, did you take account of using same road and checkpoints, wind conditions, and temp?

When I look at the pictures on E-Bay, I can see the difference. The one has tall intake runners like the original. The other one has the runners that are kind of flat on the top like the Dorman intake. The one with the tall runners ran just like the original Ford P71 intake. But they don't last as long as the factory intake

Tossing that engine cover is a free mod that’ll keep it from holding heat over the intake.

Andy I could sit around ALL DAY with you and DV. The man that got me started use to race against Bill Grumpy Jenkins. Anyway my question is where do I put a balance pipe when tuning my exhaust

I replaced that silencer with a piece of pvc & definitely felt the difference

Those gears you got will help a good bit paired with a sct x4 tuner would wake it up, it might not be fast but more fun to drive. I guess if you really wanted to get faster for cheap you would buy a eldelbrock victor jr and a nitrous kit and a stall converter. Or maybe a on 3 turbo kit for 2600.00 anyway nice video see ya in the next one.

Regarding the Dorman intake, when I was researching it to replace my OE 2005 intake (cracked heater nipple, of course) I read that the issue is that they used their older 4.6 design, which was actually an improvement on those engines, mated to the later intake port design, but of course Ford had also improved the entire intake along with the ports. The video you included really shows the difference - the older intake design is more optimized for hood clearance, so tighter, smaller, shorter runners, and a smaller plenum makes for less flow. I ended up getting a Motorcraft OEM replacement intake, in light of all that.

Right on

my 2001 merc grand marquis runs good, but not much acceleration with 2:73 gears. on the highway, it runs pretty good. thanks for the video Andy!

That head liner is boss what model panther is that

I thought those Factory mufflers what special mufflers made by a muffler manufacturer for quietness and horsepower Andorra maximum flow

Hey Andy, is there anyway to get up with you or DV to get some help specking out a cam?

I OWN A MINT 03 4.6 EXPLORER, ENGINE WAS REPLACED WITH A NEW ONE BY THE PREVIOUS OWNER, AND HAD A FEW 1000 MILES ON IT WHEN I BOUGHT IT. FIRST MOD I DID WAS REMOVING THE MAIN MUFFLER, IT IS HUGE AND HEAVY, DON'T THINK IT MADE MUCH OF A DIFFERENCE POWER WISE, BUT NOW IT SOUNDS BETTER THAN ANY V8 IN TOWN, AND MANY PEOPLE ASK ME ABOUT IT. BEST MOD I DID WAS FITTING A BIG MOUTH HOOD SCOOP THAT RUNS 2 AIR HOSES TO THE FACTORY AIR BOX, TO THE FACTORY AIR INTAKE, AND MADE THE ENGINE MORE RESPONSIVE AND YOU CAN HEAR IT BREATH WAY BETTER WHEN YOU FLOOR IT, LOOKS GREAT AS WELL, AND YEAH PEOPLE ASK ME ABOUT THE SCOOP AS WELL, JUST BY LOOKS IT IS AN IMPROVEMENT. IT IS STILL SLOW, BUT THAN AGAIN IT IS A SUV AND HEAVY. I HAVE BEEN THINKING ABOUT FORCED INDUCTION, AS IT IS STILL THE BEST BANG FOR YOUR BUCK, A SMALL TURBO AT LOW PSI (NO MORE THAN 6PSI) IS STILL THE BEST WAY TO GET POWER OUT OF ANY V8, SURE YOU WILL HAVE TO MAKE UP YOUR OWN KIT, BUT THERE ARE VIDS ON HERE ON SIMILAR FORD ENGINES HOW TO DO IT. THE BEST MOD I DID FOR MY EXPLORER WAS THE BROWN WIRE MOD, AT LEAST NOW MY EXPLORER IS REAR WHEEL DRIVE ON THE STREETS, PUSH THE 4X4 BUTTON FOR OFF ROAD USE. I WISH THERE WAS A BOLT ON SUPER CHARGER KIT FOR MY EXPLORER, ALTHOUGH COST VS TURBO IS WAY MORE.

I changed the box with a bigger opening and got a engine light on. I put it back to stock the light went out

Andy I would try a KAM reset and see what it runs for a number. Throw a can of BG 44K in the tank as well.

And sounds great

Only thing that is free is hand me downs, friendship, and your labor/time. I am not sure if the time is included anymore but a wise old woman told me this. She has passed on but the factual basis of this is from the the Great Depression and the war years.

You may want to try the J MOD. KZfaq has a killer video.

I think I would have put some chicken wire mesh over that hole to stop large objects from entering the air box!!

Looking at 60ft times, the last was best, in worse air than 1st. So maybe picked up lower rpm power and lost up top? Long tubes are about the only exhaust improvement at this point I'd assume.

Hiya Andy, I just ot a 03 Grand Marquis, practically the same car. Do you remember the under valance discreet ram air from the late 80's early 90's? It'll be a meatball job but I think I can make it happen. Also will be going with dual exhaust on mine, to reduce resistance from this single pipe one (was yours in this video single or dual factory exhaust?)

But the cars came with 235 horsepower. I'm assuming the aftermarket intake is killing the numbers. Before you do anything else that our car buy an intake. To see if the other mods you made help with the new intake

I thought Ford fixed the intake manifold issue on 2002 and up 4.6 engines?

I did the air cleaner trip to my 93 Lincoln it was worth it just to have the intake sound

Nice! Objective testing. The gears will be a hit, hope those go next. Listening to that 1 - 2 shift was almost painful, that relatively small engine pushing that heavy car down the road with pretty tall gearing I suspect (2.75 or so?). I give that little cammer credit for pushing that barge around as well as it does. I remember the days of 400 inch smogger engines that were making 185 HP so this thing's doing alright.

So little things are still little things. 😊 they can add up though!

i am looking at an 02 with 160k miles and an 04 with 210k miles same price. both are decent cars, dont know which one to choose. ?

I did always want to wrap my intake tubing in heat reflective tape like Ford boss did

I have a 1996 Ford Thunderbird with the same motor and I bought a K&N air filter and I wish I would have just stayed with the factory. Now I got to figure out how not to pull hot air in the motor. I did see a little bit of throttle response but I got to figure out another setup to where I can get cold air coming into the actual cold air intake instead of just having my cold air intake suck in radiator Heat. However if I want to I can punch it and get 7.5 seconds 0 to 60 which is a whole lot better than when I bought it doing about 9 seconds

Did you get an enginr light after the alteration. I know if you seap a civilian airbox with a police interceptor airbox and tube you can gain 5-10 hp but you need a tune after wards adding duaks to a civilian vic will also gain hp both police airbox and tube and duals will get you to the 250 hp that police crown victoria gets.

Can you clock the TPS on these like the old 5.0s?

II thought the K and N filter will spit oil on the mass air meter.

Hi Andy, will you be installing the better intake manifold?

Some work and some just make noise, back pressure loss on the exhaust?

I knew I wasn’t crazy, I replaced the intake on my marquis and I swore it felt like it had less power afterwards, I knew I wasn’t imagining things

Another awesome video Andy! How are you getting DA numbers?

Good video. Looking forward to more on this topic. I appreciate the aftermarket hot air intake mention. A popular mod is to cut off the rear cats. Please don't cut off the rear cats as they are the primary cats. The front cats are the "pre-cats" designed for when the engine is warming up from start up.

The resondator delete makes the car sound way better, I'm replacing these with FlowMaster FX... Us Panther Guys know this car will never really be fast with a 4.6... But the 'Cool' factor of caarruising in this big arse car is where its at :) BTW, I'll have the cold air mod done by next weekend!

How bout this Modd... Luaghing Gas injection... in the vent ducts :) Dang, you'll be having much fun, who cares how slow your Vick is 🤣😂😁 My P71 ain't quick, but she's perty darn Fast on the open hi-way! Fuzzz Buster required!

Gotta get an air box

Only problem with the air cleaner housing mod is that it won't pass the visual on smog inspection.

Great cars. I was a cab driver for ten years. All the cabs were old cop cars

One suggestion would've been to do 3-5 runs at each setup and take the average of the runs.

Hint: Any air filter you can see through lets dirt through. 4:14

I wish Ford would atleast have preserved the Town Car and built it past 2011. I know there were structural upgrades were necessary to meet NHTSA and DOT standards. While they were at it, shove in a 5.0 Mustang engine, a new 6 speed automatic and Stability Control

How much horsepower does Slick 50 and some good ol octane booster add? Hold my hat while I cut the exhaust off of my car! Good stuff!

The Crown Vic is ok... If you like that body style and want more HP stock, go with the Mercury Marauder! 4.6 DOHC....You can get plenty of power from them with the right "tweaks"

Open up the exhaust and throw a Marty tune and get a explore rear end would move like a 96 impala

The best "free power mods" for this boat would be to sawzall everything that isn't wheels, tires, engine, transmission, or steering wheel 😂

I'm at 800 sea level and my bone stock p71 crown viic runs 10.56 @ 69mph on draggy

Great video, can't wait to see what the Crown Vic will do! I just ordered a bunch of suspension parts for my 09, P71. I'm sure you already know that the tune makes all the difference with one of these engines. My Crown Vic playlist; kzfaq.info/sun/PLFU8SaWNbzx8PHKJZ9sCnoG7TwcHz4pVW

So all you really gained was it sounds better? Love how everyone applies old school carburetor tricks to modern fuel injection. The fuel management system adjusts for maximum power based on available air.

K and N filter, the official I hate my engine airfilter.

Andy, you think a stock CV is slow?? I had an 87 CV wagon with a stock 150 hp 302. THAT was slow! But my 76 LTD wagon, all 5000 lbs of it, with a 400 2V, was even SLOWER! And my 81 Fairmont wagon, with a 200-6, was worse yet! School buses were eating my lunch!

Thanks for sharing, My take away: Ford Pays A dozen Engineers $300k a year to design Great cars. Some 18 yr old kid making $12 dollars an hour, thinks he knows better and ruins it.

K&N filters only filter cats and dogs. Fine for racing but bad for street unless engine life does not matter to you.

I have the thunder bird 95

I've, never bought anything Dorman, that was any good. Especially, electronic! For goodness sake, don't buy Dorman cam phasers, for Ford 5.4, 3 V!

The engine Should have responded with More HP after these 2 mods.....Maybe the Baseline should have Included reading the WOT A/F ratio.....it's Possible the Ecu changed the A/F ratio & Reduced engine Hp.....

Comen sense

I have an 01 Marquis..best 1/4 mile to date is 15.11@ 92.6mph in 3000+ DA...Its got a 14 in it with some good weather. 3.55 gear Traction lok differential Flowmaster FX mufflers Gutted rear cats P71 lower air box DNA filter 70mm throttle body off E250 5.4L Steeda Underdrive crank pulley SCT X4 tuner 185° Thermostat. I'm looking to get a 2800rpm stall converter next hoping to improve on the horrible 2.10 60ft times.

take off that steering wheel cover, they ruin steering wheels

I got a 100 send me a locker 😅

Nice seats, normally I see light gray or light camel?