New daily? 1984 Corvette

Hey guys, haven't been too heavy on the hot rods lately. Life has me spending a lot of time on the highway and none of my cars were up to that level of frequent hi speed long shot drives.

I still wanted something older & cool, but it also had to be reliable, well built, fairly fuel efficient and easy to work on, so of course I settled for something that was none of those things.



I really like C4s and always have, and with a flexible budget of about $6k for a highway car I had a lot of options.

This car was listed by a small dealership nearby for $7000, but when I hit the dude up, he had just picked it up from another shop doing some work on it.

He had left it with them for diagnostics and they ended up doing a ton of unauthorized work, refused to release the car until it was paid for, and the kicker... it no longer ran when it came back to him!

I got it for the cost of the repairs - $3500. It has had a bunch of chassis work done, brakes, front end, etc and has a new transmission with less than 500 miles on it put in by its previous owner. Other than 40 yr old Corvette problems (mainly plastic) the car is really healthy. I warrantied the Autozone battery that was in it and had it running the same day and drove it home. I've been tinkering with it since and have been driving it for about 5 days.

It's a 200hp crossfire car but it feels like a rocket ship. Super tight handling, very responsive and feels plenty fast. I love it! I was looking for a black on black manual car but manual C4s are pretty rare (and I have read the transmissions are problematic) and I really really like the color scheme and wheel combo on this car.





I'll be back to working on real metal cars soon enough but I'm really enjoying this slight deviation...

 

neat, looks like fun!

I would have held out for a 85-90 with the tpi, but that's just me.

 

I could have had one, but I have always heard the 84 is the best handling C4, and this car really grabbed me with the paint scheme, wing and wheel combo, and the body is in just tremendous shape with no rust issues to speak of in the undercarriage, so it is a great starting point. I figured a 350 is a 350, so there are lots of ways to make it faster if I want to, and an LS will fit anywhere a 350 was... but for now I am quite happy with the car as is. It has no problem ripping standing burnouts without help from the brakes, gets sideways when I ask it to, stays very controllable in slides, and makes all the right noises.

 

Congratulations. Enjoy your new ride.

 

C4 huh? Sounds explosive hehe.

 

A buddy bought one when they first came out. I was prepared to be completely underwhelmed. I was quite surprised! Handled on rails and was really snappy! (especially for the era!)
Have fun with that thing!

 

No expert on the C4s, but what I have learned messing with a few, the cross-fire was a mistake as is easily shown by the one year only usage. Good luck on parts and diagnostics, especially the ECU and other 1 year parts. Same with that digital dash. Hope it doesn't die of old age.
The handling was panned as too rough and was mildly softened in later years. If it's has usual maintenance done like shocks, it's probably later model there anyway. They do corner a bit better than your truck, Mopar and T.
Follow the lube points for the doors and the hood. You do not want to replace the door handles and you really don't want the hood latches to give you issues! Make sure the release is smooth and not at the end of it's travel.
Electrical issues are often ground issues, even though they were designed with better grounding than steel body cars.
You do not want to do a radiator, it's not fun. Make sure the cooling system is in good shape.
A ton of cars of this vintage have aftermarket anti-theft. The vettes are less likely due to the pass key system, but any aftermarket alarm still in the loop is just asking for trouble.


and a last suggestion; since the shop was doing all that shady stuff to another business, I'd look over every bit of the work they did. Honest shops do honest work.*****py shops do... well check it out.

 

The Crossfire has a bad rap but it works fine other than some unintuitive quirks. Port injection is just better... there are so many Crossfire cars still on the road it's hard to argue the system doesn't have longevity. I have worked on a few customer cars before owning this one. You just can't slap a bunch of speed equipment in it and expect the computer to know what to do with it without programming, and programming that little******** EPROM chip is a lot more work than adjusting a carburetor. I have had the ECU out of this car and looked it over, everything checked out good. The digital dash needs to be rebuilt as the LCDs are dead in the center gauges but the board is fine so eventually I'll send it off.

The car handles really well which is no surprise... it has the Z51 handling package that got the C4 banned from SCCA for embarrassing Porsche 29 times in a row. It is a 'little' stiff - which is to say it rides a little softer than my Model T - but it handles as well at 140 as it does at 40.

I called the shop that had it and asked if I could get copies of the invoices for the work they did on the car. That conversation went like this:

"Hi, I bought a Corvette you guys did some work on and would like copies of what yall did on it for my records."
"Which Corvette? Oh, is it the gold one?"
"Yes, the gold '84."
"Haha." *click*

I know they did some of it, but some stuff they definitely didn't, or they*****ed up other stuff in the process. I've found a lot of stupid***** they did... from the relatively harmless broken/unhooked vacuum lines to their brand new valve cover gaskets leaking, the distributor being loose after they had it out and reinstalled it, broken oil pressure lines, injectors installed wrong, TV cable left unadjusted, fan wiring broken while monkeying on the engine, etc.

The seller was right... it wasn't gonna run again for him unless he paid someone else another bundle to sort out their work, so cutting his losses made sense. But it runs now and it runs damn good. I have a guy that can program the PROM chip for me to adjust for any speed stuff I wanna throw into it down the road. Or maybe I'll throw a Sniper mani on it, or just LS swap it if the wheezy old smog 350 starts getting tired. Right now the car just needs a lot of the little things to be really right. Plastic knobs and*****ons giving up. Vacuum lines for climate control. That sort of*****. I have a hookup for that too.

Right now the worst thing is this...



Some drooler leant on the wing and broke it. This is not a factory item and most C4 wings are lower profile wings. I really like this wing... so now I gotta either find an old aftermarket wing and paint match it or buy a new one for $550 and paint match it. Maybe this one can be fixed, but I don't know anything about fiberglass and I'm not sure my first crack at fiberglass repair should be hanging out in a 140 mph airstream.

 

Got a good deal on a parts car.



Also an 84, which someone tried badly to engine swap and did an indescribably horrific job at painting. 34000 miles on the chassis so lots of goodies on it to replace some of the more tired stuff on my car. It has some good interior bits, and all the*****ons/switches and electronics are good.

It has already donated its new MAP sensor and floor mats to my car but in the next few days it will give up its dash (the center section in mine quit working) and driver side headlight motor. Those items alone cover the purchase price of the car, but there will be plenty more robbed, like the fiberglass targa top, which will replace the busted acrylic one I have. Saul wants to build an LS swapped race car with the shell.

There were a ton of new parts inside the car too - including a brand new, really big Holley 4bbl with a polished bug catcher scoop and a bunch of nitrous stuff (hoses, solenoids, etc).

Not really sure what the previous owner intended to do with the car... it had a carbureted 350 in it which he kept. It feels like someone who didn't know anything about race cars thought he was going to build a street/strip car. But whatever.

 

https://www.corvetteforum.com/articles/hack-pre-roadkill-creation-vette-kart/

Grab as many sensors (fuel sending unit, too) and other Vette specific parts you can that Saul won't use.

 

You might want to see if you can find wiring diagrams for the 84 and the later models and see how difficult it might be to convert to the later computers where you can program them better. Here is a book that you might try to find a copy of. Its very well done and about an inch thick.

 

Former '84 C4 owner here - car was A LOT of fun!! still had the crossfire; I think the only issue I had was it would shut off randomly. Always fired right back up. Mine was an auto, and not the 4+3 either... I did put on aftermarket "correct" later Vette wheels - totally changed the look of the car! IF the factory alarm is still in it and functional (I found out the hard way mine was); you had to turn the key in the door and turn it to deactivate it. I only knew about that when the alarm went off, and a neighbor at a buddy's house was yelling up the street "PUT THE KEY IN THE DOOR". Other than the headlight doors not co-operating, it was pretty trouble free car. Enjoy it!

 

I had an ‘85 and it was pretty rough but nice at the exact same time. It was cheap but what sold me on it was mint interior and working gauge cluster. The paint was horrible but it was fun to drive

 

Lost the water pump today but Saul and I kicked its**** and since we were working on it anyway we also took the gauge cluster out of the parts car. Swapping this out wasn't too bad, so I'll send the original off to be fixed here soon so I can get the correctish odometer back in and Saul can have this one back for his car.





Looks like my fuel sender is bad so that will be one of the next tasks. The purple car has a brand new gas tank but it looks like a mother*****er to drop the tank in these things, and anyway Saul will need it.

That water pump was a real sonuvabitch!!! You have to take everything off the front of the engine and access is pretty bad, especially when it's a mix of metric and standard sizes and the sun is setting. We also deleted the smog pump while we were in there and ripped out the air injection pipes.

 

Didn't realize how bad the paint was til I clicked on the image...
My God ... Hoooow?
Did they wax the car then paint it?

That's like s.o.p. for most project cars I come across
Great find on the parts car.

FWIW, 84 TH700s are THE worst of the 700s if it's still original.
Small input shaft, much more sensitive TV cable adjuster and adjustment. Everything wrong with a 700 is just amplified with an 84 unit. Had one blow up the stator and partially shred the input shaft in an 84 GMC Sierra 1500 2wd. Cruising on the freeway, broke wind, which moved my foot .001", causing a downshift and the stator in the TC went BOOM. Find an 87+ unit to freshen up and have on hand when the 84 detonates.

 

Yeah, you now know the modern ways they stuff things together. I should have mentioned getting the alt tested, but didn't think you'd dive in so soon. It looks like a ten minute job. It's not as you have found.
Yes, dirty, ugly, a ton of sockets and wrenches, that's about right. Be glad it's not an optispark!

Sender comes out the fill hole, Watch JR Go has videos of this many times.

 

Zoom in on this one for a real trip hahaha

Good tip on the*******. It is a rebuild installed by AAMCO a few years ago with less than 500 miles on it but I have no information on it. I'll keep an eye out for a newer unit.

Don't forget I work on modern cars as a professional now haha. I still think this water pump is one of the worst I've done and I've done Audis... actually Saul ended up doing most of the work because everything was so insanely tight that I couldn't break anything loose. Every bolt sounded like a .45 and somehow nothing snapped.

 

Just a quik note: The 700r4 corvette case is a bit different at the rear for the torque arm suspension. Beefier in the bolt area of the tail housing. No bolt holes for common mount. Output shaft is shorter.

I worked on several of that gen vette steering columns. Drivers used the steering wheel as a grab bar. The top of the tilt column would come loose. People ignore that. Soon the mount holes were damaged.

If it has a V belt on the smog pump. Watch the length of the belt. Too long of belt , the pump will rub on the hood. As I recall the alternator belt and smog pump belt are near equal in length. Alt belt on smog pump equals smog pump against the hood

 

Yeah, but you open the hood, sit on the tire and think, it's all laid out and easy. It's NOT! Every little thing is a 1/4 inch too close, plus the S/M mix you mentioned. That snap is the blue sealant they did to the fasteners in response to the Japanese stuff. Usually means nobody's been in there before.

I know that many like Audi and they did fix a lot of Lambo issues, but I had early and late experiences with them and do not care for the way they do things, especially packaging.

 

One of the things I did while we were in there is delete the smog pump. It was already disconnected and the bearing sounded like a tin can full of wood screws in a tumble dryer and really just made the car sound horrible. I left the belt routing alone and used an 85" belt. Some people said deleting the smog pump leaves the P/S reservoir unsupported but the bracket still has 3 attachment points and isn't going anywhere. Plus it'll be that much easier to get in there next time.




We visited the exhaust shop today... it is now fully straight piped with the hollow cat acting as a large open chamber resonator. It sounds awesome! I'll have to get some good footage. My phone recording inside the car doesn't do it justice. It's very smooth and throaty under throttle with plenty of pops and burbles on deceleration, but it isn't obnoxiously loud unless I'm burying the pedal. The*****py old turbo mufflers on it were really hurting the sound.

 

I always liked the C4 but could never take to the early model video game dash.
A later one with the TPI would be nice.

 

Nice, enjoy. I looked at a few C4s but ultimately went with a C5 since I found a great deal on one. Fun cars, the parts car will be handy, great drivers..

 

Interesting story on the 84 Corvette, not a good trade or move:
“In 1983, then owner Wim Overweel became enamored with the new Chevy C4 Corvette that was coming out that fall as an '84 model. He wanted one ... bad. So he advertised the HemiCuda 'vert in Hot Rod magazine for the cash equivalent of the '84 Vette that he wanted ... $25,000. Ever on the lookout for Hemi cars, especially Hemi convertibles, Dave Blake, and his dad Bob Blake, saw Wim's ad in Hot Rod, contacted him, struck a deal and then hauled their Tor-Red treasure back to Arizona where it has been ever since.”

 

Hehehe. So the ratchet adjuster gizmo on the TV failed somehow while on the highway and by the time I realized something was wrong - it wouldn't go into overdrive and then didn't want to go into second when taking off from a light - the transmission was smoked. Fueled by necessity and a bit of optimism, I readjusted the TV cable and changed the fluid/filter in the transmission and I have kind of got it driving again, enough to get me home but I am going to have to replace the*******. It still acts funny around second gear and still won't go into overdrive.

Am I looking for just any good 700r4, swap the tailhousing, shorten the output shaft (looks like 3/4"?) and hit the road? Lots available for not too much money.

 

Switching gears here, proverbially and literally. I think I should just put a 4l60e in this thing. This would have several advantages, perhaps most importantly future proofing for future engine swaps. There is some kind of tailhousing adapter I need to find for the C beam but otherwise it is a bolt in replacement and I can use a standalone controller to manage the electronics.

 

Better yet, a 95-96-97 4l60e uses the same tailhousing as the 700r4 and is a direct bolt in replacement with a standalone controller, same gears and everything. I can get a built one for not too much money that will cope with a beefed up engine later... so that's the plan. There's a cheap standalone controller that makes it act like a manual valve body and I will upgrade to a better controller later as they get pretty expensive.

 

Jayzus
*does sign of the cross*
I've wanted to learn how to texture... but like on a stucco or plaster wall.

87+ have a 'K' on the case.
Seems like the factory Hydramatic tags get ripped off 700's more so than other transmissions. But if you find the tag look up the code to identify original application.

Yeop, common enough with early 700 TV cables.
Pretty sure it's a combination of the self adjuster not having enough friction/locking capabilities and the cable itself having a high friction inside the housing. Too quick of a throttle change the cable will self adjust and shoot the cable out. Age and heat contribute, but I don't recall anyone having these same cable issues with the TH200/C/4Rs

I don't care for the 700/4L60/E trans, especially in any performance context.
1-2 gear drop is 60%
It won't upshift into OD under WOT.
Even with the Vette/9C1 throttle valve sleeve it can still down shift early when you are pushing on the throttle in OD.

I *thought* there was a kit to place a 4L80E(with an 'E' delete conversion to TV cable) in an otherwise stock C4 without having to modify the tunnel nor require a custom C beam.
1-2 gear drop is only 40%
It's a TH400 with .75 OD.

If you have any ideas of throwing serious money at an AT for the C4, I'd look into a 4L80-de-E'd trans conversion.

 

I think the 4L80E is physically longer no matter how you slice it, especially with the inch or so adapter. I saw a guy that did that and although there is a $400 adapter to use the Vette 700r4/4l60 tailshaft housing, he had to shorten the C-beam and drive shaft accordingly.

I thiiiink the 4l60e will serve me fine. The hard part is finding one I can use. The early units with are proving tough to come by and they are clapped when they do pop up. I reckon I'll just have to shell out for a fresh one.

Out of curiosity, why should I backdate an E trans to a TV cable? I found the idea of eliminating the cable appealing after it smoked my 700.

 

One of the things I'm chasing down while waiting on a transmission to magically appear is oil consumption. The car suddenly started burning a lot of oil all at once, but it was only under very specific conditions. It wouldn't burn any on start-up, it wouldn't burn more or less after warming up, and it had no blowby. It would only do it after running at a low RPM for a while and then revving, and if I revved enough it would clear up for a little while. A bunch of people told me it was valve guides and not to bother and just start looking for another engine. I suspected the PCV was drawing oil into the intake but when that didn't fix it I got a little more technical. I had a feeling oil was getting into the intake somehow but there are only so many paths for oil to get in.

I pressurized the crankcase with smoke and after about ten minutes I saw just the faintest few wisps of smoke in there. Looks like oil is able to wick up the manifold bolts and seep into the intake when there's a vacuum being pulled. When I took the lid off the manifold I saw it plain as day. Since I'm this far in, I might as well yank the manifold and replace the gaskets too.

 

Bet you he's had seller's remorse ever since! And if it was a 4 speed too the price has gone way over 6 figures!!