iam looking to buy a 84 with 54k or a 85 with 45k miles on them, some people say dont buy 1st or 2nd year c4 why these cars on in mint con. whats yp is this true with 50k miles on them u tink they would be ok, help me out

 

i'd go with the 85. L98 engine comared to the crossfire

 

what he said


if you don;t want it, I might take it. 50k on an 85 is rare.

 

Not to speak ill of the 84, it is a good car....but it is the one and only one if its kind. Prior to the 84 you had a car with a carb. with years of past history. 84 was the first fuel injection based on a carb. configuration. 85 started the first individual fuel injectors and morphed from there throughout the C4 generation. The 85 does have the only chip of its generation...86 and up used a different chip. The 85 will have more in common with the other L98 based cars.

 

Welcome to the Forum!

I suggest you obtain a copy of Corvette Specs: 1984-1996 Models [Paperback]. Mike Antonick (Author), Michael Bruce Associates (Author), Michael Antonick (Author).

This paperback is a pretty good review of the C-4 years. A lot of changes to engines, suspensions, interior, exterior, tires, etc, etc during these years. For example, the press LOVED the 1984/1985 handling but most folks found it too harsh, and Chevrolet lowered the spring rates significantly in 1986.

Some time spent reading will help you zero in on the model/year that will be a best fit for YOU. Spend some time looking around, there are good prices on good cars if you take your time. Purchase the best example you can find (matching your budget) as restoration in NOT cheap. You will spend less money overall on a good car than trying to fix up a beater.

 

They made a lot of changes for '86 which make it a much more desirable year (and those following):

ABS standard.
Greatly improved ECM and programming.
High mount brake light (there's a selling point... ;-)
Automatic air conditioning option. <-- I love this one.
Aluminum heads in the middle of the model year.
Convertible in the middle of the model year.
Lots of detail changes that are not very interesting.

The '82 - '84 Corvettes had throttle body injection, not carburetors.

One problem with the evil combination of old cars and low mileage is that they always have major problems when they finally get running again. Corvettes don't like to sit for long periods of time. Connections corrode and gas goes bad. A friend of mine had mice eat up his wiring.

 

Hey John,don't forget last two MY in C3 generation, they have the same L83 power plant C4 84' has,crossfire born in 82'.

There's a lot of reason ,when you serch along a one decade generation car,to go straight to last MY,reason why it's obvious, last MY assimilates all improvements that went through 10 years of production and road testing.

In this case,C4 at the end of L98 power plant (1991) shows us two different air metering system,MAF or SD(speed density),MAF is a expensive sensor to replace ($300), it lasted on L98 untill 89,SD uses a MAP sensor that is cheap ($60),if you have to replace parts this informations are important.

ABS option is an important feature to consider,when you'r breaking a 3500lb sport car...it comes in 86...

Better flowing aluminum heads,from late 86....

New 165 ECM in 86',this unit was upgraded from 160 baud to 9182 baud transfer data rate...

In 1987,the old TH700r4 transmission unit was fully upgraded and was re-designated 4l60,Trans-rebuilder never choose an early case to start a rebuild...
In 1990 interior's car was upgraded to a mordern style,if you compare a 89' interior design to a 90 ,89' seems prehistoric

So ,in my opinion,if you like an early 80' style C4 go with an 89',if you like a midle-restyling car,betwen old 80' and last LT1 generation choose a 91'

 

85 and up cars equiped with manual transmissions came with the stronger d44 rear ends. That was the main reason I went with an 85. In my state anything over 25 years old can be registered as an antique and is emissions exempt. This is why I avoided getting anything newer. I have a very cheap classic car insurance policy (agreed value) and pay little in excise taxes. Good for a a car that I use on a limited basis.

 

In my country car becomes tax free and special insurance for classical at 20...so now we have classical car taxes and insurance since 92' MY...
Again on the topic,choose an 86' at least,new ecm,new heads,abs,...softer suspension ...an example 85 burn off module it's discontinued, you can find on Ebay for $ 150!! 86' maf power relais and burn off relais are 12$ cheap china products available everywere...some details are important,btw my Corvette is an 85'...trust on me

 

I wouldn't turn my nose up at the '84. It's fuel delivery system (cross-fire= 2 throttle bodies) has been used on numerous GM vehicles over the last 25 years and is reliable. I like the simplicity of the '84 & '85 model years (I owned a '85 and loved the car). Good luck with your purchase.

 

Most reliable vehicle I ever had was a TBI car. If all is in order they run wel and are very very simple to diagnose/work on
Not much in the way

 

i see most of guy here defend TBi talking about semplicity and reliability,i can agreen with them,a carbureted C3 is simple and reliable too...again an example:you go with an 85',after a couple of year,lerning more about modds,you go with a new heads combo , camshaft and larger injectors,now your chip need to be modified...all of us in the ECM and tune section will tell you that 870 ECM is too slow for datalogging and it is a one year chip and isn't used that much,than upgrade to next 165 (1986),but a lot of wire to be spliced ...then why don't buy an 86'...

P.s this is a famous 165 swap coming from Tihrd Gen
http://www.eecis.udel.edu/~davis/z28/ecm_swap/
this guy starts his swap report with this words:
The ECM that came in my 1985 Z28 Camaro with the TPI motor (VIN "F") is a series 1226870 (870) control unit (car computer). This model was used in the '85 F-body cars with TPI motors, Corvettes, and some 2.8l V6 (VIN "S" and VIN "W") (*Reference*) cars. One major problem when tuning an EPROM for this ECM is that the diagnostic data (ALDL) is transmitted at only 160 BAUD!. This works out to about a 1.25 second interval between the 25 Bytes of data. I have only been able to get about 6 to 8 data samples during a Quarter-Mile DragStrip run which you can imagine does not provide much feedback for tuning. (sample data are at the bottom of the page in PDF format)
The ECM that came in 1986-1989 TPI Fbody's and Vettes is a series 1227165 (165). The ALDL data rate in this model can supply diagnostic data at 8192 BAUD. The (expanded) data stream of 64 Bytes cycles through every 62.5 milliseconds (16 per second) at this BAUD rate.

870 data rate http://www.eecis.udel.edu/~davis/z28...p/870chart.pdf

165 data rate http://www.eecis.udel.edu/~davis/z28...p/165chart.pdf

 

get the 85 for sure. Lots of upgrades from the 85

 

I went from 84 directly to 88. I upgraded the 84 because the C4 just kept getting better and better. If you get the 85 it's just allot of work if you do engine work yourself, all that tpi takes time to come off. If you don't care about the extra HP and want a simpler car then stick with 84.

 

In the world of Corvettes, unless its a special edition of some sort, newer is almost always a little better. GM has done a good job of slowly improving their vehicles, yet never going backwards in the performance department.

No matter what you choose.... welcome to the corvette community !

 

Never going backwards in the performance department? So the C2 's and early C3's were lower performing cars than the late 70-early 80's C3's ? There were some serious steps taken backwards during those years in performance, don't you think?

 

Okay, in the last 25-30 years...... but whatever.

 

Again 86,at least...i'm talking about facts and data,L98 it's better than an L83 engine, specs are facts and you must agree with facts...
Are aluminum better flowing heads better than cast iron heads?......YES
Is a faster ECM better than a 20 time slower ECM?.....................YES
Is ABS feature a goodie for a sports car like this?.....................YES
Is an upgraded TH700r4 (87) better than early unit?..............................YES
Are 17" stock wheels better than 16"?YES(so you have enough room to add C5 caliper)
Are larger brake disc better than smaller.....................YES
there are lots of things not mentioned...I repeat,i have an 85,but when i bought it only thing i know about Corvette was they'r fast...Now,knowing much more i'd buy an 89' or a 91 SD in the L98 range.

 

what's so significant about the mileage numbers? those mileage numbers cut a lot of really nice cars. i'd expand those numbers out a bit...