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Shop Subscribe Latest News Jalopnik Reviews The Morning Shift Nice Price Car Buying Video The Inventory Drive Free or Die. Drop your email here and get our stories in your inbox. But it’s still fascinating. Advertisement Photo: vette333! ( Ebay ) Doug Nash was a famous Detroit hot-rodder in the 1960s, who, after retiring from racing, got into the engine and transmission business, eventually developing a manual transmission for General Motors’ mighty Corvette for the C4's 1984 to 1988 model years. That electro-hydraulically controlled two-speed overdrive was automatic, engaging when the driver let off the gas (i.e. under low load), and could be turned on and off via a button on the top of the shifter. Just look at the secrets that YouTuber GearboxVideo reveals in the clip above, including an awesome miniature valve body. This second video gives an explanation of how the clutches work with a planetary gear set to yield an overdrive ratio for your fuel-saving needs in second, third and fourth gear. And I’ve got to respect it for that. David Tracy Posts Email Twitter Sr. Technical Editor, Jalopnik. Always interested in hearing from auto engineers—email me. Cars: Willys CJ-2A ('48), Jeep J10 ('85), Jeep Cherokee ('79, '91, '92, '00), Jeep Grand Cherokee 5spd ('94). Share This Story Get our newsletter Subscribe More from Jalopnik So What Were Those Secret Flying Wing Aircraft Spotted Over Texas. They were pretty common in MGs and Triumphs as well, and turned up in some Euro Fords, and I think some Italian makes as well, possibly even Ferrari. The Volvos had a fourth gear sensor that prevented use in 1-3. Some of the MGs were set up so you could use the OD in 3rd or 4th. See all replies. Learn more - opens in a new window or tab This amount is subject to change until you make payment. For additional information, see the Global Shipping Programme terms and conditions - opens in a new window or tab This amount is subject to change until you make payment. http://www.wieswioska.pl/userfiles/bosch-maxx-it-washing-machine-manual.xml

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If you reside in an EU member state besides UK, import VAT on this purchase is not recoverable. For additional information, see the Global Shipping Programme terms and conditions - opens in a new window or tab Delivery times may vary, especially during peak periods and will depend on when your payment clears - opens in a new window or tab. Learn More - opens in a new window or tab Learn More - opens in a new window or tab Learn More - opens in a new window or tab Learn More - opens in a new window or tab Learn More - opens in a new window or tab Please try again later. Contact the seller - opens in a new window or tab and request a postage method to your location. Please enter a valid postcode. Please enter a number less than or equal to 1. You're covered by the eBay Money Back Guarantee if you receive an item that is not as described in the listing. Find out more about your rights as a buyer - opens in a new window or tab and exceptions - opens in a new window or tab. All Rights Reserved. User Agreement, Privacy, Cookies and AdChoice Norton Secured - powered by Verisign. Yes, my password is: Then I have to ask the all mighty Car Lounge, WTH is this. And how does it work. I can't imagine a Corvette with dual gear levers. Ad in question: As for two gear levers.we haven't even gotten to twin sticks yet. It has a separate unit for the OD mounted outside of the gearbox. There's logic to it as well, as it can engage and disengage automatically as well.Then I have to ask the all mighty Car Lounge, WTH is this. I can't imagine a Corvette with dual gear levers? It was a stop-gap to keep a manual transmission in the Corvette until they developed a 5-speed.It has a separate unit for the OD mounted outside of the gearbox. There's logic to it as well, as it can engage and disengage automatically as well. This transmission was made by Doug Nash. Nash, at some point, was absorbed by Richmond Gear. http://karmen-shop.ru/userfiles/bosch-maxx-instruction-manual.xml

For a similar product still available like the Hone-o-drive L88 mentioned (At least in effect, not necessarily through the same method), check out Gear Vendors.My shop teacher in high school had one and loved it. I wish I'd been able to drive it, as I've never driven one.Give it a listen. Assetto Corsa Discord Link. Join us for some sim racing fun. May your slip angle be great and your bed not be the couch! I'd just use it to create a 5th gear basically.Digital Point modules: Sphinx-based search Content on vwvortex.com is generated by its users. vwvortex.com is not in any way affiliated with Volkswagen AG. Typically the cheapest shipping is the slowest, choose wisely. Allow 48 hours for tracking to show status. Refusals are charged any shipping charges incurred. Read our FAQ. For general Corvette information, see Chevrolet Corvette. It was the work of a team under chief Corvette designer Dave McLellan, who'd taken over from Duntov in 1975. In a departure from the fiberglass panels of its forebearers, the C4's rear bumpers and panels were made from molding plastics, a sheet molding compound. The C4 fastback coupe was the first general production Corvette to have a glass hatchback (the limited edition 1982 Collector Edition being the first Corvette equipped with this feature) for better storage access. The roof panel made from fiberglass or optionally from clear acrylic was removable. The Corvette C4 came standard with an electronic dashboard with a digital liquid crystal display instrument cluster. It displayed a combination of graphics for speed and RPM, fuel level, and used digital displays for other important engine functions.The primary design emphasis at launch was therefore focused on handling and braking, with an all-independent light-weight suspension and wheels and all new brakes with aluminum calipers. Spring rates were sequentially softened for the 1985 model year. The C4 did not use separate body-on-frame construction like its predecessors. http://www.drupalitalia.org/node/67456

This was not a unibody assembly, as none of the exterior body panels were structural members. Due to a styling decision to use a targa top instead of T-tops, there was no structural member tying the windshield frame to the halo as on the C3.This unusual transmission was a synergy that allowed the Corvette to keep a stout 4 speed, but add an overdrive. As technology progressed, it was replaced by a modern ZF 6-speed manual transmission. The LT4 produced maximum power output at 5,800 rpm and 340 lb?ft (461 N?m) of torque at 4,500 rpm.Being early in the rollout of this new technology, there were only 15 different resistance values available. Once thieves discovered this weakness, it markedly reduced the value of this early system.None were made available to the public as official production vehicles. All were destroyed except one, VIN 1G1AY0783D5100023 (white with a medium blue interior), fitted with a 350 cu in (5.7 L) L83 205 hp (153 kW) V8 engine and a 4-speed automatic transmission. It was displayed above the factory entrance for years until it was restored and is now displayed in the National Corvette Museum in Bowling Green, Kentucky. The 1983 model delay was due to problems with parts supplier quality issues and production line changeover issues. GM decided to cancel the 1983 production year model and started the 1984 model year Corvettes early. Regular 1984 model year production began on January 3, 1983 and delivery to customers began in March 1983.The Corvette division approached Lotus with the idea of developing the world's fastest production car, to be based on the C4 generation of the Corvette. Lotus also designed a unique air management system for the engine to provide a wider power band by shutting off 8 of the 16 intake runners and fuel injectors when the engine was at part-throttle, while still giving the ZR-1 a power output of 375 hp (280 kW) when at wide open throttle. http://araone.com/images/4-wheel-drive-manual-vs-automatic.pdf

Due to the heavier engine and body work along with wide tires, the ZR-1 is 200 lb (91 kg) heavier than the standard C4 Corvette. The ZR-1 came standard with the UJ6 Low-Tire-Pressure Warning System along with an ABS system manufactured by Bosch. The FX3 suspension system was engineered by Bilstein and was similar to the system used in the Porsche 959 albeit with modifications from the Lotus Formula 1 division. The system used a gas-over-oil shock absorber whose hollow center shaft came fitted with an adjustable orifice which controls the flow of oil in the shock absorber. The system allowed for six damping settings in each of the three driving modes namely Touring, Sport, and Performance and had 14 total steps. Servomotors coupled with a microprocessor governed the vehicle's speed and adjusted the suspension system accordingly.The crankcase has integral four- and six-bolt cast-iron mainThe four camshafts of the engine are driven by a roller chain and actuate hydraulic lifters that eliminate valve lash adjustment. The four-valve combustion chambers feature centrally-located spark plugs which act in combination with dished aluminum pistons enabling for a compression ratio of 11.0:1. The engine held 12 quarts of oil, 7 more than the L98 engine. The LT5 also came with a unique two valve induction system along with 16 tuned-length intake runners and a specially designed intake manifold using three throttle bodies. The small primary throttle body was for responsive low speed operation while the two large secondary throttle bodies enabled for full-power usage. The engine used direct-fire ignition: Four coils ignite two spark plugs simultaneously, upon receiving their cue from a crankshaft sensor acting in combination with the ECM. Spark advance andA distinctive cooling system incorporating a 15 larger radiator ensured that the operating temperature of the engine remained the same as the L98 despite the differences in construction and operation. https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1626c6d4f166a0---compaq-6510b-repair-manual.pdf

The transmission used Computer Aided Gear Selection (CAGS) which forced the driver to shift from first to fourth under low power urban driving conditions. The transmission has a tweaked ring and pinion ratio of 3.54:1 and a lower final drive ratio of 3.33:1.The engine assembly involved 95 drilling and boring completed at the Mercury Marine plant. The engine was largely assembled by hand and was Dyno tested before being sent to Chevrolet. Mercury Marine secured two LT5 V8 engines for itself.It was distinguishable from other Corvette coupes by its wider tail section, 11-inch wide rear wheels and its new convex rear fascia with four square shaped taillights along with a special red ZR-1 badge in between.The rear convex fascia that set the 1990 ZR-1 apart from the base model found its way to all 1991 models, making the high-priced ZR-1 even less distinguishable. Further changes were made the following year in 1991, including extra ZR-1 badges on the fenders and the introduction of Acceleration Slip Regulation (ASR) or traction control. For model year 1993, modifications which were designed by Lotus were made to the cylinder heads, exhaust system and valvetrain of the LT5 bringing power output up from 375 to 405 hp (280 to 302 kW) at 5,800 rpm and 385 lb?ft (522 N?m) of torque at 5,200 rpm. In addition, a new exhaust gas recirculation system improved emissions control. The model remained nearly unchanged into the 1995 model year, after which the ZR-1 was discontinued as the result of waning interest, development of the LS series engines, manufacturing cost and the forthcoming introduction of the C5 generation. A total of 6,939 ZR-1 models were manufactured over the six-year period. Not until the debut of the C5 based Z06 in 2001 would Chevrolet have another production Corvette capable of matching the ZR-1's performance. AUTOSKOLA-SCP.COM/files/case-450-skid-steer-service-manual.pdf

Chevrolet approached Callaway to offer such an option after seeing the power output the tuning company was able to extract reliably from modified twin-turbocharged Alfa Romeo V6 engines. The car came with normal Chevrolet warranty as well as additional one year 12,000 mile warranty from Callaway Cars. The conversion consisted of taking the engine out of the car and performing a thorough set of modifications along with installing two turbochargers. The result was the engine rated at a reportedly conservative 382 hp (285 kW). The car was classified as a standard Corvette by the EPA so it wasn't subject to additional registration requirements.This marked the return of the convertible body style, absent from the Corvette lineup since 1975.It also features a removable black top and came equipped with everything, including its own unique emblems. The 35th Anniversary car is the 2nd Serialized Corvette in the production history of the C4 Corvette, with each car receiving an engraved number plaque on the console. 2,050 cars were built and a quoted 180 of these were manual transmission cars, making this a rare and collectible model.For 21 years, the car was stored in a climate controlled environment.All leather seats have the 40th emblem embroidered due to an error on the drawings sent to the seat supplier.The Corvettes were primarily used to introduce the 43 NASCAR drivers in a parade lap prior to the start of the race during driver introductions. There were thirteen Red and twelve Black convertibles used, and most carried two drivers on the lap, with their names displayed on the hoods.The Grand Sport moniker is a nod to the original Grand Sport model produced in 1963. A total of 1,000 GS Corvettes were produced, 810 coupes and 190 convertibles. The Grand Sport also has wider tires and the coupes were outfitted with small rear fender flares. The C4 Grand Sport also had a unique VIN compared with the standard C4. {-Variable.fc_1_url-

It included Sebring Silver paint, silver 5-spoke alloy wheels, special emblems and seat trim. Of the 5,412 built, 4,031 were coupes and 1,381 were convertibles.Manual trans not available by regular production until Jan 1984 (18 produced in Sept 1983, factory tested, then delivered to early orders in Nov 1983).New were Third brake light, antilock brakes, electronic climate control, and key-code anti-theft system.Callaway twin-turbo offered through dealers with GM warranty.New wheel design. All white 35th Anniversary special edition coupe.Interior redesigned to incorporate driver's side airbag.Traction control is standard.LT1 receives mass air flow sequential fuel injection.Minor exterior restyling. Indy Pace Car special edition.Collector Edition and Grand Sport special editions. Only C4 year with OBD II diagnostics. Selective Real Time Damping is a new option.The project would become the CERV III (Corporate Engineering Research Vehicle III). It was first unveiled in Detroit Automobile Show in January 1986 as Corvette Indy prototype car.The project lasted until 1988 with mixed success. The final Corvette GTP built (HU8811.01) as raced by Peerless Racing underwent extensive wind tunnel testing by GM, with many of the 'aero' developments (such as the short tail design) being used in later production C4's. The Peerless GTP Corvette also went back to the V8 small block engine from the turbocharged V6.Retrieved 9 July 2011. Lincolnwood, Illinois: Publications International, Ltd.Retrieved 2010-10-05. By using this site, you agree to the Terms of Use and Privacy Policy. NOTE: This does not fit any other application other than above. The item in the picture is the actual photo of the item being sold. Super high amount of views. 0 sold, 1 available. More Super high amount of views. 0 sold, 1 available. You are the light of the world. We may earn money from the links on this page.Think about it. http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1626c6d664a488---compaq-6515b-user-manual.pdf

If years ago we said that by 2020, Chevy's next Corvette would be mid-engine ( which we totally did ) and Toyota and BMW would revive the Supra you'd be excited. But if we told you they'ed use an automatic transmission exclusively. You'd probably cancel your subscription. Manufacturers used to put stick shifts into anything they could touch with a hole saw, but that stopped when automatic transmission evolved into something good. Even the quickest cars of the last decade use some form of automatic shifting. However, when it comes to 20th-century performance cars, manual-equipped examples generally retain more of their value than automatic ones. Plus, a five- or six-speed stick of that era easily outperforms its three or four-speed slushbox alternative. These offerings aren't as obvious when you think of the manual-trans past. The combination was as unexpected as it was awesome, but few buyers equated German luxury with a clutch pedal, so not many were sold. It's the one we'd buy. Crazy, right? And the 255-hp GS version had one too. To repeat: There were manual Buicks! (Of course, that’s because they’re rebadged Opel Insignias, manual versions of which weren't exactly rare.) There was even a turbo version with 150 horsepower. Don't like Caravans and Voyagers.Available only with the 4.0-liter inline-six, the brand's five-speed manual lightened the XJS and made it fun in a way an automatic never could. Fewer than 200 were sold stateside. Based on Ford of Europe's Mondeo, which offered a manual, the X-type wagon ended up with one, too, for two years of production. Only 1602 wagons were sold, and far, far fewer were manuals. Still, we'd rock a stick-shift ES without hesitation. Strange is good. Did you know the secret to immortality is drinking a quart of pickle juice each morning. Awe, who are we kidding. You're already on Craigslist looking for a manual Mazda 5 in a new tab. See you in the afterlife. chrishuzzard.com/userfiles/files/case-450-skid-steer-operators-manual.pdf

While that pegs our cool meter, only 397 iconoclastic customers took Mercedes up on it. How's this sound? A big rear-wheel-drive Toyota luxury sedan with the contemporary Supra's inline-six and a five-speed manual transmission. Oh, what a feeling! You may be able to find more information about this and similar content at piano.ioYou may be able to find more information on their web site. For a better experience, please enable JavaScript in your browser before proceeding. It may not display this or other websites correctly. You should upgrade or use an alternative browser. Nash was a successful drag racer turned transmission expert. According to the article it was in essence a Super T10 four speed with a two speed overdrive attached to the back of the transmission that could be engaged in 2nd, 3rd or 4th gear. I have never driven one of these cars so I wondered what are they like to drive with that transmission. I take it they did if for fuel economy but maybe not. What was the shifter arrangement. Was the overdrive electrically engaged. Hopefully someone can let me know. RIP Doug Nash I leave it in OD 90. Much maligned tranny, drive it smoothly, service regularly, it will last.The Super T10 was a pretty stout unit in its heyday as I recall so is it the OD that is the weak link? The little auto unit did have its problems, as range said service it lots about every 10,000 fluid change. If you are into hard core racing it will let you down. My 85 there is a od switch on the console. Trying to find someone who knows anything about them and who has worked o them is very hard.Parts still avail. Seems the memory or his explanation of how the OD works was a little off. Love the thread. Learned a lot too. Here's the thread from when Kent had it up for sale in '13. I almost bought that baby. Very nice car. 1988 Corvette C4 Base Coupe Fully Loaded R.I.P. Doug Nash Colin. To get into the auto mode you need to engage the clutch and push the button on the top of the shifter. The gear selector indicator acts as the button. This car when you start it though starts in auto mode even if auto is shut off when I turn the car off, I am not sure if it is suppose to do that or not.To get into the auto mode you need to engage the clutch and push the button on the top of the shifter. This car when you start it though starts in auto mode even if auto is shut off when I turn the car off, I am not sure if it is suppose to do that or not.Please register to receive all manner of go-faster benefits on CCF. Click HERE to login or register. The site may not work properly if you don't update your browser. If you do not update your browser, we suggest you visit old reddit. Press J to jump to the feed.I wonder if it has to do with gears, since it says it’s a manual. Enjoy the miles you'll put on it. I had a 1990 camaro Iroc-Z that I litralley sold a week ago and then this popped up with perfect timing. Don’t forget to wave. I'm on my 4th vette and this one was 1 of 4 for me.Right now it's completely stock. It's definitely getting a better exhaust, but other than that I just want to cruise in it so I'm not sure what other mods would improve it. All rights reserved Back to top. Find the answer to this and other GM questions on JustAnswer. Corvette 1986 4 3 Manual transmission shift switch corvette 4 3 overdrive manual trans will not engage how do I remove and replace it Just push the button on gear shift and let off gas thanback on -if everything is working you are in overdrive.Find the answer to this and other GM questions on JustAnswer. Corvette 1986 4 3 Manual transmission shift switch corvette 4 3 overdrive manual trans will not engage how do I remove and replace it Just push the button on gear shift and let off gas thanback on -if everything is working you are in overdrive. Something went wrong. Cancel Thanks, we'll look into this. All Rights Reserved. You’ll probably end up making just as big a mess on your garage floor. In a great many ways the overdrive was very similar to the old two-speed Powerglide. This particular overdrive unit was originally designed for the Jeep CJ-7 and CJ-5. Chevrolet was working on such a tight deadline for the fourth generation Corvette that there was no time to develop a new unit specifically for the Corvette. All of this was really done to meet the EPA fuel mileage regulations, but at the same time the overdrive fourth gear provided a high speed cruising capability that easily exceeded all the earlier Corvettes. Thanks to the EPA the Corvette was a 150 mile per hour car. There are really three unique, and different, algorithms programmed into the overdrive ECM, one each for second, third and fourth gears. The overdrive ECM logic is incorporated in into the main ECM, or the chip, as it’s commonly known. I guess all computers are not created equal. The real trick, however, is to get rid of all the complicated electronics and turn this transmission into an 8-speed. Well, not quite by accident. Actually Chris Petris, who used to build transmissions for the Corvette Challenge racing series, helped me with this. There’s a switch on the side of the transmission that tells the computer which gear is engaged. The switch is engaged every single time you shift the transmission, whether the overdrive is engaged or not. It’s no wonder that this is usually the first item to wear out. I could hit the switch on the console to turn on the overdrive and it might not actually engage until I drove some twenty miles down the road. You can imagine how aggravating this was. When Chris and I couldn’t locate a replacement switch right away we simply grounded the switch by running a very short shunt from one terminal to the other. This effectively made the OD a completely mechanical unit, operated only by the interior switch, which in my case is on the console. This was like giving me a new Corvette. While Chevrolet designed all the electronics to pass the EPA fuel mileage cycle, I simply wanted a useful transmission.This switch is on the left side of the transmission, and can be seen easily if you have the car on a lift. This switch moved around a little during the years, but it was always the switch towards the rear. You won’t be using this harness. Now make a little jumper wire that fits into the two terminals. You can remove the switch from the transmission and make the jumper wire on your workbench if you prefer. If it takes more than fifteen minutes you’re goofing off. You should treat this situation just as you would any automatic transmission. You’ll even create the same type of mess on your garage floor. Be careful not to lose any of the bolts. Pay particular attention to the sealing edges of the pan. At one time GM used RTV sealant on this surface. That wasn’t such a great idea and now you can get the filter kits with gaskets. If you don’t find a gasket in your car you can assume that the fluid hasn’t been changed in a few years. These overdrive units are notorious leakers. Using a gasket on the surface will solve most of the sealing problems. Once everything is clean you can install a couple of bolts to hold the oil pan back in place and carefully tighten the bolts using a cross pattern to get it nice and even. Mobil 1 is the obvious choice but it seems everyone has a different preference here. Just ask some questions and see what other owners are using. There were some internal changes made and the clutch material is different on the later cars. The best thing you can do for this overdrive is change the fluid and filter once a year, or at least every 15,000 miles. Don’t be shocked if your magnet is covered with steel shavings. That simply means the magnet is doing what is designed to do. You can remove the magnet for cleaning and then place it back in the correct location. You’ll notice that the difference between fourth gear and fourth gear overdrive is almost forty miles an hour at 4,000 rpm. Since most of us don’t drive much over 80 mph on the highway it simply means we get pretty incredible gas mileage. I’m still wondering where you can actually use all that gear ratio. Even at Sebring, which is a very fast course, I only get into 3 rd overdrive. Maybe I need to drive the banking at Daytona.Placing the jumper wire in this switch turned my overdrive into a manual overdrive. All of the stuff that was designed to meet fuel mileage requirements is now gone. The switch is easy to modify, but if you have any questions about your abilities just call the Corvette Clinic in Sanford Florida. We have the traditional small block Chevrolet engine bolted to the very traditional T-10 transmission. Then that’s hooked to yet another transmission which looks strangely similar to the old Powerglide from the fifties. Then that second transmission (or overdrive) is bolted to a huge length of aluminum U-channel (the Driveline Support), which in turn is bolted to a differential carrier in the rear of the car. What’s amazing is that it works so well. He has also written two other best selling Corvette One deals with the 1968 to 1982 Corvettes, How to Restore and Modify Your Corvette 1968-82, while another deals with the Sting Rays from 1963 to 1967, Corvette Restoration Guide 1963-1967 All of these books are available from Corvette Central. Some one pointed out earlier that jumping a switch not connected to any electronics will do nothing. The engine should also be warmed up.Are you replacing an existing transmission. Changing from an automatic to this manual transmission. Third, Not sure what jumper you are referring to. Replaced relay. Car IS NOT hard to get in reverse. Shifts fine. I have no OD. The light comes on as it should between gears and when I hit the button. I just found out mine being a later design only has a 1st gear switch. If the first gear switch fails can I jump it like in the article above for the second gear switch to get OD to engage. I don’t know what has failed. Pressure switch, solenoid, 1st gear switch? Mine works great in 3rd only. Can’t figure it out. It’s a newer one with only 2 switches on the side of my trans. Steve Does this effect gas consumption. Does it effect the top speed.And how much does it hold and how do u check level I have the unit out and want to install it in a 57 chevy. What do I need to do? Chevrolet has discontinued it These parts are NLA. Break it, you’re in deep, expensive, ca-ca. This pump is driven by the rear wheels. Until a certain road speed is reached, there will not be enough pressure to safely engage the overdrive clutch without allowing it to slip. There is a pressure switch inside the unit that doesn’t allow the OD to engage until a minimum adequate pressure is reached. If the overdrive circuit is energized in first gear, and the car is accelerated from a stop, at some point, while still in first, the switch will close and the OD will engage. Probably violently. Many owners like to use the clutch when shifting into OD to lessen the forces on the components. You can’t do this when it engages on its own, because you can’t anticipate it. The faster the car is going, the higher the output of the pump, and the higher the pressure. This is INVERSE to the amount of torque the clutch has to absorb and transmit. In first gear the transmission is multiplying say 300 ft lbs of engine output by 2.88 is 865 ft lbs going through the overdrive clutch to the wheels.1,91 2nd is 573 ft lbs, 1,33 3rd is 399 ft lbs, and 1:1 4th is 300 ft lbs. Note the very large step between the torque in first and second. The original design wasn’t intended to absorb the higher torque applied in first gear. And the pressure to make the clutch hold is the lowest in first gear. Exactly inverse of what needs to happen.