What would be the main engine/performance differences between 1990 (is that L98?) and 1992+ LT1? I'm more interested in low-end torque and smoothness than hp. Also whether one's easier to work on (maintenance stuff like changing plugs). Thanks.

 

If you do some searches here and in the technical section, you'll get your answers,,,, do some research....

 

90 = L98 - 245hp 345 lb ft torque. ---- 3.07 gearing hp/torque ratings slightly different(according to Corvette Specs).

92+= Lt1/Lt4/Lt5 = Lt1 300hp/340 torque.

L98 is a torque monster, L98 pulls hard then starts to level out at higher rpm.(I think) Lt1 pull is more even/constant through entire rpm range. As far as working on them, i can't vouch for how it is to work on the L98s.

But I'll definitely wait for far more knowledgeable members to chime in before I think about uttering another word.

 

L-98 is the base model Vett workhorse and fairly easy to work on vs the LT-1. Both models have their issues, the 92 is faster but has the dreaded problem optispark system I believe. If this is your first vette purchase I would suggest a L-98 to cut your teeth on. Goldcylon

 

Someone must have woke up on the wrong side of the rock.

 

 

The '90,'91 is the most refined (though '89 the best, IMHO) of the L98s; the '92 is the 1st of the LT1s.

Though the L98 is rated at 240/245chp a simple mod raises that to 250/255chp.

The LT1 comes with a more efficient exhaust system, so the L98 responds much better to exhaust mods.

With a few fairly simple mods you can have the L98 turning out 300chp and still have the low end torque.

Either the L98 or the LT1 can be modified to turn out around 400chp by doing heads, cam, valve train, etc mods.

Indeed the L98 is pretty easy to work on. Spark plugs & wires are a snap to change.

 

Are you sure, I don't think this has ever been cover before. Or the lack of C5's waving at us....

 

If you've never driven an LTx, the L98 feels very fast. After you've driven an LTx, the L98 feels like it runs out of breath way too soon.
Which it does.

Smoothness is a wash.
Maintenance is also a wash. (I know lots of folks are afraid of the Opti, but those are folks who've not owned one, usually. I have had zero problems with my own Opti, as have lots of C4 owners.)

Larry
code5coupe

 

I own a 1989 L98 and really like it. Have only done exhaust mods so far plus some free stuff, but it has responded well. I don't think I would choose a 1992 LT1 if going that route. It seems the '94 '95 '96 cars were a little more refined. However, if the cost and condition of the cars are the same I would go with the 1992 over the 1990.

 

65ZO1 Why do you think 1989 is best? Also, which simple mod are you speaking of that adds 10 HP?

 

I was researching L98's and LT1's and there are many websites discussing torque. This one is good:

http://roadstarclinic.com/content/view/104/118/

I have a '91 with the L98. The article explains how you should look at torque and HP ratings. For example, the L98 hits its max HP at 4000rpm. But the redline is 5K+. In other words, you might as well shift at 4000 because you are out of power. The LT1 is definitely better, but the L98 is no slouch. Both great engines but each year for C4's GM improved many things.

Rocco16 points out that if you have the chance to drive them both you would notice the difference. I would agree with his assesment.

 

As been stated a zillion times before, try to buy the newest model that you enjoy...
I personally wanted the L98 over the LT1, but I'm not so dumb as to think that there isn't a 35-45rwhp difference between the two. A bolt-on LT1 would probably edge my mild 383 in a race.
Having said that, working on the L98 is pretty easy (especially if you are able to remove the smog stuff), it pulls hard down low, is great for smoking the tires and seems to be pretty durable.

 

My advice to you is to go with a 95 or 96 (LT4 for all stickshifts).
95-96 had the vented optispark. This prolongs its life.

At bare minimum go with a 94 - at least you will get the extra economy of the sequential fire fuel injection system and MAF system.

I have a 93 and get 16 city and 24-25 highway. Some of the 94+ guys talk of 30 MPG on the highway. I wish I was that lucky.

95-96's also had the 13" J55 front brakes standard.

Go with a stickshift car no matter what. Itll be worth something if you keep it long enough.

Ive never driven an L98, from what I hear its a 'tractor motor'. Lots of torque and then runs out of steam.

Good luck in your decision.

 

 

The '89 had no cold start injector and still had the MAF to measure air flow instead of relying on a MAP & other sensors to calculate flow.

Aside from that, the '89 was the last year to have the tilt wheel, the digi-dash and no damn air bag.

The simplest & cheapest mod on '88-'91 was to remove the "frisbee" from the front of the water pump pulley. Removing that parasitic drag gave me a gain of 1mph at the traps, i.e. 10chp.

 

O.K. thanks. I removed the frisbee first thing. I also like my stock 3.54 gears and quick ratio steering.

 

Usually I buy a car for a short period of time. A long time for me with a car is 3-4 years. I never intend to keep a car much longer than that.

Any car that looks like it cost me money I dump. I don't mod, or repair anything more than brakes, tune up, or a battery.

Ive owned over 100 cars and very few have cost me money when I sold them. Case in point out all the Corvette's that I owned (10) the only one that cost me money was a LT-1.

Not because the car need repairs it didn't but the resale value fell daily.
I wont buy a car that will cost me money to own.

LT-1's are in free fall. A nice LT1 here is under $8k.
Theres no way to own a LT-1 and not have it cost you money.
Its an over complicated car, with born in issues. The C5 is another car with more than its share of problems.

They're both beautiful cars but owning one will bite you in the wallet.

For me the only C4 worth owning is a L98.
L98's are cheap, easy to repair, fast, excellent performers and they wont kill the bank account.

Sure folks will say cars are not an investment? If cars werent an investment there wouldn't be any car dealerships, or car loans.

The 1991 Corvette is the best C4 ever built.
If money isn't important to you and you don't want or need it, buy whatever you like. But to me it is important so I choose my cars carefully. With over 100+ cars it pays to know your cars very well.

I also work for a dealer for the last 15 years and Ive worked on and driven over 1000 cars and trucks. Buy it right and you can't lose.

Buy it wrong and you lose at the gate.

 

[QUOTE=65Z01;1558761556]
Aside from that, the '89 was the last year to have the tilt wheel, the digi-dash and no damn air bag.


Did you mean Tele wheel, because my 90 has a tilt wheel?

 

I think the opti spark issue on the corvette LT1 engine is over hyped. I make this statement as most corvettes are not daily drivers and driven in the rain and snow as much as other model cars are. (camaros, impala's etc.) I was doing routine maintenance on my 92, I removed the opti spark to replace the cap and rotor. Although I did find one of the ignition contacts on the cap carbon tracking to ground, there was no moisture related issues found. I did install the upgraded msd cap. It provides vacuum tubing and instructions to modify older units similar to the upgraded 94-96 opti spark.