Our test subject pauses to catch its breath between pulls. At the end of the day, the car had gained 13 hp and Contrary to what our predilection for megabuck tuner cars might suggest, we at VETTE are acutely aware that our readership is not composed entirely of professional athletes, real-estate magnates, and other car-crazed croesuses. And while our saturation point for bespoilered quad-turbo street freaks with outlandish DayGlo paint schemes will always exceed that of our colleagues in the auto-mag world, we're not above occasionally making room for a vehicle that represents a more reasoned approach to the modification game.
With that in mind, we've decided to introduce a project that more closely resembles the sort of thing we coupon-cutting types are likely to undertake.
Our mission is simple in concept, even if its execution is certain to prove more daunting. We'll be shooting for Zchallenging accelerative performance-low 12s in the quarter sounds about right-while minimizing our cash outlay and avoiding extraneous read: non-performance-enhancing modifications.
Simply put, if a part isn't designed to make the car run faster or launch harder, we won't be expending any ink on it here. Cast in the role of the working-class hero is a 75,mile '96 automatic coupe, complete with Florida-issue Rebuilt title, sun-faded Polo Green paint, and a headliner that droops like Cronkite's eyelids. And while it certainly won't make realizing our e. For our first round of installations, we decided to focus on the cheapest of the cheap, the idea being to effect a verifiable, if not noticeable, improvement in the Vette's output for the kind of money one might drop on a couple weeks' worth of groceries.
All of our installations and dyno tests were performed at Anti-Venom, a Seffner, Florida-based performance shop specializing in late-model Corvettes.
A comparison of the factory air lid and the Breathless piece appears to lend credence to BPP's claims of a percent flow improvement. Baseline Accustomed as we are to, and even 1,hp C5s and C6s, we were primed for disappointment when Anti-Venom proprietor Greg Lovell strapped our virgin '96 to the shop's Dynojet chassis dyno for its first pull.
We were pleasantly surprised, then, when the car registered a respectable After a backup test produced virtually identical numbers, we unlimbered the tools and got to work. Breathless Performance Products' C4 Modified Air Lid does the factory one better by incorporating a fully open-faced design reminiscent of a picture frame.
All of our "gain" numbers are based on a two-pull average. Follow-up tests with the paper filter yielded identical results. While 3 horses may not sound like much, the extra airflow provided by the BPP lid is sure to play a more critical role as we bolt on additional performance gear.You can use the fuel rails on all of the intakes, but you can only use the fuel rails on the later model intakes.
The LT1 Optisparks are very similar between years, but there are only 2 styles : and The 2 cannot be interchanged without front cover and camshaft modifications. There are 3 main differences in the units : drive method, ventilation system, and electrical connection. The Optisparks use 2 different drive methods : Spline drive and Pin drive.
On spline drive systemthe Optispark has a splined shaft that mates to the camshaft timing gear. The gear is clocked so the shaft only goes in 1-way for precise timing. On the pin drive systema pin extended from the camshaft runs through the timing gear and into a slot on the Optispark, and the shaft from the Optispark runs through the camshaft center for better bearing support. Vented Optisparks have 2 small vacuum line attachments left photo.
Corvette Data, News, Racing, Lifestyle, & More
These attachments allow for engine vacuum to remove moisture from the Optispark unit. Non-vented Optisparks have no vacuum line attachments right photo. Instead, 3 small holes are located at the bottom of the unit to allow for ventilation. This causes failure when driving in rainy weather or through a puddle. Some advantages of the vented Optispark are 1 the ventilation system allows for a longer life span and less misfires, 2 the bearing and drive method allow for longer bearing life, and 3 the larger diameter front seal reduces the change of oil leakage through the cover and into the Optispark.
You can convert from a non-vented Optispark to a vented Optispark by changing the Optispark unit, the front timing cover to a model, camshaft timing gear to a model, adding the vacuum lines, and changing the Optispark extension harness to the later model. The camshaft does not necessarily need to be changed, but you will need to drill the cam centering hole deeper for the Optispark unit to slide in all of the way. We have a convenient kit available for those who wish to upgrade to the vented Optispark.
The exhaust ports and holes are also in the same location. All LT1 heads use self-aligning rocker arms. The intake manifold is proprietary to the LT1, however, a standard small block Chevy intake can be modified to work.
There are no coolant crossovers on the intake, coolant is routed through the back of the cylinder heads through a crossover tube. All LT1 engines use center bolt valve covers. They use similar internals, exhaust manifolds and oil pans. The main difference in the LT1 is the reverse cooling design, which cools the cylinder heads first, then the block.
Because of this, there is no water that passes through the intake manifold. Coolant is transferred from head to head by a steam line on the back of heads.
Build Some Power With a '92-'96 Gen II LT1
The thermostat is located on the water pump. Also, the water pump is cam-driven, rather than belt driven. Inan LT4 was available in the Corvette. The LT4 had the same features as the LT1, but had larger valves, larger intake ports that were located higher, and an intake to match. The LT4 also came with a more aggressive cam to enhance the better heads.
LT4, Aluminum, cc ports, LT1 cylinder heads share the same head to block bolt pattern as the standard small block Chevrolet. The LT1 and LT4 intake manifolds appear the same from above, all LT4 intakes are powder coated red from factory, but the difference is in the intake ports.See more. C8 Corvette Overview. Corvettes For Sale. Submit News. If you're a fan of unbridled, all-American horsepower or dreamed of owning one of the most revered sports cars in the world - the revolutionary Chevrolet Corvette - you are in the right place!
We built CorvSport. Black Corvette Wallpapers. Read More. Garrett Randall has been into cars since the age of 13, as he explains in the video below. It started Running from July 6 to July 10, Barrett-Jackson Auctions held an online-only version of its oft-televised collector car auctions. Blue Corvette Wallpapers. A fairytale end Classic Corvette Wallpapers. Just over a month ago, we brought you the report that a Corvette C8 had been dropped off a When it comes to performance-on-a-budget, there are few sports Custom Corvette Wallpapers.
Corvette Logo Wallpapers. Yesterday, we featured an HP twin-turbocharged time attack Corvette C6. Load more. Model Research. Last Friday, we As we scour the classifieds on the weekends to find interesting, weird, or collectible Corvettes, we more often than not Corvette C8 Wallpapers.
Corvette C7 Wallpapers. Must Watch Corvette Videos. C8 Corvettes. C7 Corvettes. C6 Corvettes. The Best Corvettes at Mecum Indianapolis! C5 Corvettes. C3 Corvettes. C2 Corvettes.
C1 Corvettes.See all 12 photos. Conversely, it can also be regarded as the ultimate production version of the original small-block Chevy and a testbed for the technology that would advance the small-block into the new millennium. Since its introduction inmuch ink has been spilled some in the pages of this very magazine about the Gen II engine. We'll spare you the nostalgic musings on Chevrolet engine families and get to the heart of the matter: LT1s are available in junkyards right now.
So we thought it was time to take another look at these engines. We wanted to know why they were made in the first place, how they differ from the original small-block Chevy, what their strengths and weaknesses are, what their performance potential is, and what people are doing with them. A Little History Designing a new engine is a tough balancing act. Stringent fuel economy and emissions standards are always being imposed on the auto manufacturers, so any new engine being developed has to run cleaner and be more fuel-efficient.
But at the same time, cars get heavier each model-year with the addition of new safety features, infotainment devices, creature comforts, and power everything. The new engine has to make enough power to handle the excess weight, plus not feel slow to the driver and burn less gas.
In an attempt to improve upon the outgoing L98's hp, GM's designers set a goal of net horsepower for the LT1. To meet these goals they employed fairly standard techniques of increasing the compression ratio and improving the cylinder-head design. But they supported these changes with some interesting technology. But the differences, though few, are substantial enough to warrant the new-generation designation. The engine block and cylinder heads are unique and cannot interchange with the previous design.
Also specific to the Gen II are the ignition and cooling systems. Reverse flow Think LT1, and you likely think "reverse-flow cooling. But how well has the system ever been explained? To be fair, reverse-flow cooling is not a new thing. Smokey Yunick developed a reverse-flow system for some of his Trans-Am race cars, and a few independent engineers and engine builders have developed systems of their own.
But the LT1 was the first mass-produced engine with reverse-flow cooling. So how does it work? Let's review the basics first. On the Gen I engine, the water pump bolts to the front of the block.This would be a great place to make an Optispark joke and then tiptoe around GM's failure to build a solid ignition system in the '90s, but at this point we don't even care to make the effort.
I mean, sure, we could probably go on to say that it "works every time, percent of the time" or that it operates flawlessly except for when it doesn't, but really, we're friends, let's not mince words here. The Optispark sucks and if it hasn't left your LT1-powered ride on the side of the road or racetrack yet Like some sort of cruel villain, the Opti waits in the shadows until you really need it to work and then strikes, either with terrible misfires or no spark at all.
Sure, it has one good quality in the high-resolution optical pickup, but seriously, for anyone rodding on a budget or trying to get by with a simple bolt-on LT1 for fun, the Opti can be one of the worst and most frustrating part of the experience. What really makes the Opti issue worse, if you can believe that is possible, is that it is stuck underneath the factory water pump and behind the crank pulley, which makes swapping it for a new unit even more frustrating and time consuming than usual.
As you can probably tell by now, this is an article about fixing the Opti in our Firebird project which we call the Dirty Bird and, as you have probably also gathered, we're a little aggravated to be dealing with this issue again, as it seems like we have to do this to every LT1 project we take on. Luckily, for all of the Opti's faults, in this day and age, there are certainly solutions. Racecars can use a crank trigger, streetcars can use an aftermarket billet Opti or some sort of LSx coil conversion, and those without an overhanging cowl can even use a distributor with a carb-style intake manifold yikes!
For our budget Dirty Bird project, it made the most sense to pick up a used Bailey Engineering LTCC conversion system, which made fixing the Opti issue as simple as laying a new ignition harness in place, hooking up a couple of wires, mounting some used coils and turning the key. Yep, you don't even have to touch the stupid thing except to pull the stock plug wires off and you can move on with your build plan knowing it won't ever give you issues again.
The LTCC conversion uses a slick module to convert the Opti's high and low resolution signals into commands for a set of LS-style coils, which still utilizes the factory PCM to decrease cost and increase simplicity.
Best of all it cost us less then a new Optispark, and installed in just a couple of hours. We picked up plus horsepower, an equal helping of torque and four-tenths of a second with our new LTCC coil conversion system and the Dirty Bird is running better than ever! Can we turn a pile of parts into a whole car in one week? A collection of Camaro products any gearhead would like to own. Treat your classic Corvette to a professional dyno shop super tune.
We take you through the short but careful process of installing an aftermarket passenger sideview mirror on a C3 Corvette.
Corvette Chief Engineer shared insights about the C8 Development. GM High Tech Performance. How To.Produced from tothe C4 is one of the most popular Corvettes ever made. Chevrolet made many C4s over the years, and their relatively low price made them a good entry-level, or starter, sports car. The model did change over the decade-plus that it was in production, and some have held their value in the collectors' market better than others. Chevrolet designed an all-new Corvette in the early s, but the prototypes—about 40 in all—produced for the model year had serious quality issues.
Not only were those not sold to the public, but these quality issues also delayed the subsequent production of fourth-generation Corvettes until the model year. Despite the setback, was the second-largest production run in Corvette historywith over 51, cars produced.
Overall, C4 Corvettes make up the second-largest group after the C3, of which aboutcars were built in that generation's year period. The design of the new generation Corvette was distinctively different from previous models.
Once you see a C4—with its futuristic, slightly squared off front and back-end—you'll never mistake this generation for any that came before or since. Also worth noting is that the convertible Corvette returned in after an year absence. Both major and minor changes were made to the C4 during its production run, and a few special editions were also produced.
The standard engine power in the C4 Corvettes ranges from horsepower in a model up to horsepower in one built in A engine can put out horsepower. Base Corvettes have a horsepower LT1 engine. Certain special editions such as the Callaway twin-turbo models can generate up to horsepower.
These are naturally more expensive and hard to find. The — Corvettes are by far the lowest-priced 'Vettes on the market. As such, base-model C4 Corvettes are not generally considered collectible, and it's doubtful they ever will be. Essentially, a C4 from the '80s makes a good starting point for an enthusiast's ride, but it is a poor investment for resale.
The C4 body and frame debuted in after the quality issues of delayed the Corvette's release. The second-largest number of Corvettes produced in any year were produced in —51, cars in total. The suspension for this year was softened 25 percent from This was also the first year that Bosch fuel injection was used.There should be enough here to get you going in the right direction.
Some of these I have pictures of completed harnesses I have modified for easy installation. I have a lot of pictures so please be patient and let them load. If you find this information useful, or have suggestion on something to add, let me knowI will try to get it done.
My goal is to help the hobbyist to be able to complete a harness transformation by them self. I would only hope you send the PCM to me when it comes time for it. I do not charge for ANY information. Sample schematic similar to what you may see in the following pages. This may help you to learn how to read the schematics. For parts list for fuse block, obd2 diagnostic port, and wiring instructions, click here! Typical 'External' Connections This is so the PCM can remember learned information about the engine over time.
This includes idle control, fuel trims, and transmission adapts. This is what 'powers up' the PCM. Even the COIL wire on some of those went dead when cranking.
Build Some Power With a '92-'96 Gen II LT1
After cranking, power was restored to the coil through a resistor, lowering voltage to 6 volts. The signal is only present for two seconds at key on. Fuel pump operation resumes when cranking over. So, if there is a condition where there is a bad crank sensor, fuel pump will come on, turn off, and will not turn on when cranking.
However, the signal needed is opposite how you're brake lights work. If you vehicle was equipped with a lockup trans to begin with, you probably already have the proper normally closed switch mounted by your brake light switch. If you do not, you can use a relay to perform the same thing. There are then a normally open leg and a normally closed leg on the relay and a supply.Standalone LS Swap Harness: If I Can Do It, You Can Do It
PCM can be programmed to match tire size and axle ratio for you're swap, so this signal is calibrated. The stock LS tach signal is 4 cylinder type signal. This can be programmed as 4, 6, or 8 cylinder signal.
How to wire up a fan relay Relay coil draws less then 1 amp. Make sure the ground for the cooling fan is a good one, also ensure there is a good ground from the battery - side to the frame. This uses a 5 terminal relay for the on on the right in this schematic.