if youre looking for cheap affordable, quick and easy performance mods to make your c4 corvette faster. then look no further! in this video i talk about each of those mods
Not sure of the L98s had this, but the Coolant Bypass for the Throttle Body is another great mod to do. Brings down the incoming air temps and its very simple to do and requires minimal tools. Great Vid! -Luis
Those are all basic delete mods on any 80s era cars gotta love how cars from the 80s where all around better cars after deleting half the stuff from the car
I'm just glad that there's somebody that is doing mods on cars that normal people can afford, sadly doing attainable stuff doesn't get you the ad revenue
Best thing I ever did to mine so far was a set of ARH longtubes. Catless 3 inch pipe back to an x-pipe then to my Magnaflow mufflers. It thanked me in the top end of the rpm range.
@@just_a_rapperjetblack9556 It was a big project to get everything fitted but I believe it was worth it. I currently only have one video of it at low rpm. I may post it on my channel until I can get better footage. I'm hoping to get some gopro footage of the exhaust here soon.
@@just_a_rapperjetblack9556 I posted a short 14 second video of it on my channel if you want to check it out. I'll eventually have a better one up once I can get better footage.
The spare tire is a structural piece in the event of a rear end collision. It diverts the force coming into the rear down into the floor instead of into the rear mounted gas tank. Removing the rear tire puts you at a high risk of death by inferno.
This is funny I just bought a 85 a few days ago and looking for some cheap mods. Watching the video I keep going into the garage (Its hot in FL I dont feel like sitting in there watching this) and every mod I see in the video has already been done to my car except for the exhaust. Kinda like the guy I bought it from watched your video and did all the easy stuff. Great video
Don't touch the EGR! If its dirty, cleaning or replacing the EGR will make a world of difference. But if its working, there is No power gains from deleting it. It only recurculates exhaust gases during light throttle cruising, it's closed all other times.
I'm looking at getting one, keeping the spare, but I'm gonna slap thinner headgaskets on it, 1.6 rockers, mild retune, probably gonna tune for 93 with 4 hole or even 12 hole injectors.
The "frisbee" only weighs 3-4 lbs and you forgot the coolant bypass for the throttle body, iit actually does give free hp with a much cooler intake charge.
@@ah4800 For the price and ease of the mod, you can't go wrong. It may not add much heat to the intake charge, but it will add some. It's not just the throttle body that gets heated, it's the manifold behind it that gets heated too. Just ask any TPI owner that has done this mod how much cooler the entire plenumn is from it. There's more surface area there than you think.
i owned a 91 and 92. on the 91 i changed out the very restrictive mufflers to muffler delete and while it was apart i drilled out the rear catalystic converter which was clogged from the foward pre cats dissentergrating and sending their guts down stream. that got me more boost and great sound on the cheap. i also installed the airfoil in the throttle body. fast and cheap mod that seemed to work a little.
@@nicknorthington3171 all LT-1s raced a twin turbo 300ZX beat him by two car lengths the only 2 cars that I got beat by back then was a 383 Camaro Z28 that my friend had it ran like high 11s. And there was a mustang running around town 1995 5.0 had full bolt-ons cam heads and gears.
Sure wish i knew this stuff 35 years ago when i had my 90. Have a 16 zo6 today and have been researching mods from day 1 and hell ya she is fast!! Great vid thku
I've heard the spare tire acts as a structural member in case the car is rear-ended, and needs to be replaced with something in order to keep the car safe, if removed for weight reduction.
Firstly, the EGR delete won't make one single bit of difference to power output, it does not recirculate exhaust gasses at WOT, and there is no point in removing it unless it is faulty or stuck open, and absolutely ZERO power to be gained. Secondly, the air injection reaction system simply blows air into the exhaust headers when in open loop, almost only ever when cold. Removing it will have absolutely no impact on how well the engine breathes. It "may" give a couple horsepower at lower RPM due to reduced parasitic drag on the belt, but that is it. I think maybe it would be a really good idea to get your facts right before you start telling people how to modify their cars, someone might come along here and actually think you know what you're talking about.
Couldn’t agree more. I dislike channels that do either “mods” that don’t do a thing, and then the channels that go all out and spend 10k on an engine then call it a budget build. If you really want to “mod” your C4, put AT MINIMUM a better intake. Then if you feel like it, either get your heads ported or just replace them. Then do a full exhaust. You maybe gained 5hp with what you did in this video, money could have been spend on a tune up and restored more of the power. Just IMO
Well it won't be just your opinion, it'll be the opinion of anyone that knows anything about engines and engine management systems in general, which this guy has indicated maybe he doesn't...
@@johnwilkins6871 The only thing I agreed with was the air box and K&N filter. Screwing with any part of the smog system is stupid, counter productive, and... oh yeah! Illegal AF! Plus inviting problems with ecm, sensors. Pointless. Also muffler delete is stupid and annoys the hell out of me. Loud is not a performance sound. You have finally saved up for a Corvette, don’t f*ck it with half-ass, clueless mods. Don’t disrespect the Vette, save for proper mods. IE, a full exhaust system designed for the car. It isn’t hard to figure, more air in and out= power+efficiency+a real performance sound, not an old work truck sound. Too many tools on RU-vid can barely afford a C4 and are clueless about how to repair, restore, or mod correctly. They don’t seem to understand that having a cool car from the 80’s, 90’s, is much, much more than just barely scraping together a few grand to buy a car that is no doubt in significant need of know how and TLC.
I couldn't make it through the whole video without having to interject. EGR is important. When you are running hot and burning cheap gas the possibility of detonation occurs. Two things happen. The heavy near knock pinging is picked up by the knock sensors. The ECM then retards timing to kill the knock, but it gets some help from...... You guessed it. The EGR valve. The point of the valve is just that. It introduces an INERT gas (spent exhaust) which causes a very quick temperature quench of the combustion chamber. Result? Knock killed immediately, and ignition timing restored to pre detonation setting. I'm not farting in the wind here... Master AST over 25 yrs. I am aware of shop owners who deleted EGR only to be sued by a customer because their engine piled up. They were chasing a stuck EGR and plated it off... Runs great now!! Man it flies!! Correction.... Flew.
🤣 BS... EGR was removed from my corvette and numerous other vehicles, and I never had issues with detonation from it. Verified with scantool knock count checks. EGR is used to control oxides of nitrogen emissions on older cars. Most newer cars use better catalytic converters to break them down instead.
Stock Z51 mufflers are open at both exit pipes. Significent performance increase over regular mufflers. Head pipe (pre pup cats) is 2 1/2" as opposed to Ca. Purposed vehicles.
EGR - Makes no difference. Its only active when cruising. Smog pump - makes no real difference. Might gain half an hp in friction reduction. The real benefit to it is having less random hoses and wires running around the engine bay, which makes working on the car a lot easier. Frisbee - Its a little less rotational mass. Might be worth it but gaining 10hp from it is a big stretch. More like 2hp. Still, it serves no real purpose so removing it isn't a bad idea. Air box delete - the stock air box has more than enough air flow. The small fins on it don't really obstruct anything at all. I read on a forum somewhere that a guy dynoed before and after and had zero gains cutting up the air box. The only way to benefit here would be an air ram intake. -Insulating the air intake system - I have never heard of this one before. I would be curious to know if there is any actual gains. I feel like most of the heat transferred would be through direct metal on metal contact with the lower intake portion of the engine itself, and that the surrounding air might actually work to cool the intake rather than heat it. Could be a pro or a con, would need testing to see. Muffler delete - This one will actually make some extra hp BUT your car will be too loud. You are better off deleting the cat and calling it a day. These vehicles were designed with performance in mind. If you want to make more power an air ram intake, long tube headers, cat delete, tune/chip, and maybe the frisbee mod would be the ways to go. General maintenance stuff like testing the functionality of the MAF/O2 sensor/TPS, making sure there are no vacuum leaks, making sure the radiator is clean and free of debris, and making sure the air filter is clean would also help in performance.
Without any dyno or dragstrip time you join the countless hoard of Internet horsepower wizards. On the dyno a typical K&N air filter will show the same horsepower increase as simply replacing a dirty stock air filter with a clean stock replacement air filter. There are some neat tricks that you can do with a flipped C4 air cleaner assembly to make an effective ram air system (with the trade off that you can’t drive your C4 through deep water puddles in the rain). Hot Rod Magazine made the ultimate light weight C4 in their hack-a-vette go cart. Don’t stop with meager 30 lb weight drops - go for a 1,000 lbs or more.
Okay here’s some info about the smog pump delete... you need to have a car less or self sustaining cat to do this mod. All the smog pump does is pump O2 into the catalytic converter so it can correctly react with exhaust gasses. Without this pump it will only take a few days for your car to clog it’s converter and be underivable. I had to delete mine due to a check valve failure which melted all of the unfindable electronics and I did not yet have an exhausts and spent three months trying to find why my car wouldn’t accelerate, did all 3 cars and voila
The smog thing is to preheat the catalytic converter, the main thing with it is it puts drag on the engine being turned by the belt so there isn't something else to spin, I also moved the air temp sensor up on the intake like the newer ones
Why would you move the intake air temp sensor? It is there to measure the temperature in the plenum, and that is where the ECM expects the reading is being taken from. Don't ya think if GM believed it would make more power moving the sensor there they would've done it themselves?? Doing what you did will at best do absolutely nothing, and at worst make it run too rich, causing the O2s to tell the ECM to pull fuel out. Either way it was a total waste of time and money. The O2s give the most dominant say in fuel mixture adjustment, the IAT is WAY down the pecking order. It is placed there on LT1 cars because the ECM and later PCM expects that is where the reading is being taken from. It is a different sensor, and serves a difference purpose for a different management system. Put it back where it belongs, it won't foul your O2 and cats, and enjoy the better fuel economy while getting the exact same power.
@@ranbymonkeys2384 HAHAHA!!! Righto buddy ;) You share your rather poorly thought out mods on a public forum then when you get called out on it being a waste of time and money doing what you did your response is "mind your own damn business"??? Have fun reinventing that wheel :)
@@CaseTheCorvetteMan Machinist for 14 years, how are you doing. Yup you exhaust wust also be a waste of money because they tuned that car at the factory and you go messing it up. See my point. I hate sophomoric troglodytes, I can build the damn thing. THE WAY I WANT NOT YOU!!
@@ranbymonkeys2384 Callaway tuned my C4 at their facility right after they made their own exhaust and built the LT1 engine the way i am more than happy with it. And ya know what? They left all the sensors right where they belong, because they knew there was no point moving them. Where was the IAT sensor on the Callaway Twin Turbo cars? Yep, in the stock location. Why? Because that is where it is meant to be and moving it is only ever going to do more harm than good. You're only kidding yourself if you think it isn't. I've got to assume you are speculating on the exhaust on my white 94, which was a 383 built by me, and tuned by me well over 15 years ago, the only thing factory about that engine was the location of the sensors. Sure, you can build it any way ya like, no one is disputing that fact, you do whatever you want. Been in the C4 game close to 3 decades, seen pretty much every pointless mod that was ever put in the Ecklers catalog.
Removing the air system is all pretty much all aesthetics. On the LT1/4 cars the air injection system is a mess. I installed shorty headers in my 96 and the bolt gets practically welded into the exhaust manifolds. After destroying the tube trying to get it out, I decided to remove all the clutter. I'm not going to pretend to get any performance gains here. Just less crap in my engine bay obscuring my nice new shiny headers for a nice clean look. The LT1/4 cars also have a resonator that you can safely delete for an x-pipe. Keeping the stock mufflers gives the car a beefier sound, honestly how the car should have came as it's not very loud. You can still add aftermarket mufflers without making it anywhere near obnoxious and possibly illegal where you live, unlike a muffler delete. The air box system is actually designed very well on C4s. I wouldn't waste money on anything there. Cut out the box if you really want. As for anything else save the money for something that really matters.
EGR will lower chamber temp 2 - 3 hundred degrees. Combustion effiency gained by delete. Timing curve needs modification when doing this mod. Need new prom.
If you get a 09 challenger diffuser kit for your 84/96 c4 corvette & Bonded to your spare tire you will have a understanding how wind well now keep your car less turbulent
The only one of these “mods“ I would personally recommend would be modifying the air box and installing a K&N filter. I’ve opened up the area behind the license recessed area for cold air on my 96 LT4. Disconnecting any part of the EGR is pointless, and I would also discourage modding the AIR system. You won’t gain any power, likely even loose power with EGR removal, (probably won’t notice much with AIR system removal), sometimes causing issues with the computer and sensors. And like it or not, these systems are there for a good reason. Plus there is the whole “illegal AF” part. The suggested mod that really annoys and is a real pet peeve of mine is doing a muffler delete. Don’t take this personally if you have already done this, but louder is NOT a performance sound. With the early C4 especially, an 8-10hp increase is quite optimistic. With only 240-245hp, the sound you will end up with is more old work truck than performance sports car. The significant choke points with the stock exhaust are up stream of the stock mufflers. The tiny exhaust tube size, the transitions from the exhaust manifolds, catalytic converter(S), to the mid-pipe resonators, which on some earlier years even drops to a single pipe. Of course the stock muffler is not great but cutting them off while leaving everything else up stream will net you little more than LOUD. My recommendation I realise can be expensive but it will pay dividends in spades ♠️. I’ve been working on/modding C4’s since around ‘94-‘95. A full exhaust system designed for the car is the mod I always first recommend to anyone who is new to the wonderful C4 Corvette. A good quality performance exhaust(cat back)system can be had for $700-$1000. I can not see spending at least $300 to have a muffler delete installed. The advantage of a free flowing system is obvious, but the other significant gain is a proper, tuned performance sound that the C4 needs and deserves, not the ratty truck sound of just hacking the mufflers off. I know some won’t agree, mostly with the cost. But taking the time to save up, you won’t regret it. Add to this over time with good quality shorty headers, hi-flow cats, then a proper computer tune, the gains without cracking the engine open are significant. A little patience while saving up will be well rewarded.
@@ranbymonkeys2384 The EGR system/valve closes when the engine is warmed up, operating the same as if it were removed. This is something that has been reviewed and known for as long as the EGR. If functioning properly, there is no power gain, no efficiency gain. It just lowers HC’s during warmup. New engines don’t use EGR. If you are triggering a code, you have a sensor problem or EGR problem.
Have a C4 1990 can't find a smog pump anywhere what pully set up did you use to replace it , your help would be greatly appreciated,and who is it made by.
Unfortunately "IN CALIFORNIA" bro if you remove the smog pump, there goes your chances of passing smog and smog inspection. And messing with the exhaust system OTHER THAN MUFFLERS is a fail. Some smog stations can be VERY picky and strict to the letter of the law with intake systems. I've done all those DELETES for horsepower and lightning the weight. It works BUT the head aches of passing smog is NOT worth it sometimes. Still great info, I have a 91 Corvette with 17,000 original miles, not messing with anything unless I upgrade to a 2015 LS from a Cadillac Escalade. Good horse power and torque from the factory.
Oh wow, it's Mr Random. I haven't seen this channel since I had a Crown Vic. Now that I'm looking at an L98, here he is again. A man of good taste, I suppose.
i bought mine on ebay. i did all the smog deletes, Frisbee and throttle heater bypass at the same time. i installed 2 cherry bombs instead of the muffler delete and it sounds amazing . cheers
EGR could (it depends on what limits they have for older cars) it’s a huge factor in NOx reduction. not sure about the air delete. I think it sends air to the main cat even when warmed up to keep burning HC effectively. btw, air makes the CAT hotter because of the O2. Then if you have front preconverters they preburn extra HC (fuel) and protect the main one but ceramic converters close to exhaust manifolds can break easily and clog the rear so I would recommend metallic core as preconverters.
hey, you and me both, could lose 50lbs off our waistline if we are honest. That would make the car faster as well. So far that hasnt been enough of an incentive for me to do it yet lol.
The Airbox "Mod" doesn't really do anything unless you are making over 650hp. All it does is allow more water and debris into the filter. I have seen a 383 making 450hp using the stock airbox and not losing any power over a completely open one.
@@MrRandomReviews I got an 87 recently with 78k it runs like a dream. I did the intake cover cutout recently it definitely helps. I also have a 2014 F150 limited in case you’re looking for a truck to review. 2014 was the last year of the last gen.
@@MrRandomReviews I totally disagree with this statement! So thumbs down on this comment. Thumbs up on the video but down on the comment. You should have as many Corvettes as possible!
I have a freind with a 600 ish hp corvette that his grandfather built and im thinking about getting a c4 and mod the crap out of it and one day super charge it or turbo charge it and turn it to a drift monster
the K&N filter doesn’t filter anything but large particles, still I would use it on track days. OE filters are very good at filtering and get even better while used until they take too much dust.
The real upgrade that you missed was the easiest and most effective modification: Air Foil on the throttle body between the two Air inlets ! Honorable Mention should be the Performance Chip Upgrade on the ECU.