So I am talking about like 1985-1996 (skipping 1984) differnces between performance. In my area, 1985-1988 ish are much cheaper than 1992 and up. I know 1992 and up had the 300hp LT1. I am just wondering how much better a 92-96 in terms of performance than a 85-91 would be.
I know the 0-60 is about a second better in the later ones, the top speed is about 10 higher in the laters, but is it a big noticeable difference? Any imput is good, thanks!

 

I had a 1991 with the 250 HP L98 engine and automatic tranny. I now have a 1992 300 HP LT1 with the auto tranny. There is a noticeable difference in acceleration from a stop between the two, but I know most of it is from the 3.07 rear axle in the 1992.The 1991 had the 2.59, as I recall.

I have driven automatic LT1 cars with the standard rear end and they seemed very comparable to the L98 cars. Remember, the L98 engine has lots of low end torque so its performance at lower speeds will be comparable to the LT1. At higher RPMs the LT1 will do better.

 

unless you are going to be racing the answer is an early C4 can be just as much fun as a late C4. I'm not counting the LT5 or LT4.

I had an 86 that was a lot of fun with just exhaust work.

 

Haven't had my 89 to the drag strip yet but they are rated around low 14's. A friend had a 95 LT1 and was running 13.7-13.8 stock at Beech Bend in Bowling Green. My car has precat delete Y pipe, high flow cat, cat back exhaust, 1.6 roller rockers, valve springs, shift kit, pulleys, I think that's everything. It feels as fast as an LT1 car but I don't have numbers to know for sure. I would guess I'm around 13.9-14.1. At least that's my hope!

 

I think your time numbers are about right. I have seen a lot of LT1 cars in the mid to upper 13's and the L98 cars in the low to mid 14's.

The mods on your car are very similar to what I had on my '87. I had a flowmaster catback, 1.6 rockers, throttle body air foil, and an SLP chip. I got high 13.9's with that setup.

By the way I saw your comment about the air foil. While I couldn't really feel any difference, there was some. With the stock chip mine had a low speed hesitation/bog with the air foil and no problem without it. When I put in the chip I could use the air foil again. It doesn't do much, but it does do something.

 

The previous owners put all the parts on the car. I had an airfoil on my 91 Z28 L98 and moved it into my 95 Trans Am and couldn't tell a difference. But, in the grand scheme of the total package of my Vette, I can see that it might be helping. The only mods my Z and TA had were Flowmaster muffler. My next power mod will be headers. Once I find someone to help me put those bastards in! I'm only mildly good at working on cars.

 

When stock, my '88 ran 14.0@98mph or so. My '96 LT4 Collector Edition consistently runs 12.7@108.9. Handling-wise, the '96 isn't nearly what the '88 was, but is also much less harsh and more livable. Overall, there's a surprisingly large difference in refinement over the years. The '96 is a far nicer car overall.

I have owned 2 '86s, '88, 96 LT1, and currently I have 2 '96 LT4 cars. All of them have very comparable acceleration/handling within their respective year groupings. The two LT4 cars are too close in acceleration to tell a difference, so I don't think the high/mid 12 second time is unusual.

Chris

 

I've had both - several early C4's (an 85 and two 90's) and a 96 LT1. performance wise, both my early and late cars, would break any speed limit in town - seriously, late C4 LT1's and LT4's will preform better than the L98. that's pretty much a no-brainer. the low end torque of the L98 can rival the LT1, but a stock L98 will start to peter-out just north of 4000 RPM. from red light to red light, the L98 can be as much fun as the LT1. remember the old saying - "torque wins races - horsepower sells cars."

one side note, my 85 SEEMED to perform much better than both my 90's, and I would say close to my 96 LT1 - both in acceleration and braking. this is a SOTP call. I bought my 85 used, and i'm pretty sure it was bone stock - just seemed like a strong running L98. my 85 did have the G92 rear end, and my 96, the base axle.

 

Here is some data that might help make some distinction between the two



In applications where L98 rpm can be held between approx. 2500 to 3500 rpm, then it clearly has an edge. However, in practical terms, except for that narrow 1000 rpm range where the L98 is king, the LT1/4s produces nearly the same or more torque across the rpm range; the LT1 out to approx. 5000 rpm and the LT4 (not graphed) adds approx. 800 rpm to the LT1s torque curve.

Note: To make a long story short, the runner length of the L98's TPI are a carry-over from the rather anemic 305 cid SBC (Camaros). In order to get at least some performance out of the 305 ci, the Bosch TPI setup was developed, and the runner length was judiciously chosen to produce torque in the rpm range most drivers would appreciate it - all things considered. Although the diameter of the runners were increased for the 350 ci Corvette, the characteristics - the torque curve, specifically - remained.

In 1992 the LT1s were advertised to have about 330ft# at the crank, whereas the L98s were about 350-355ft# (depending on the source); only a 20-25ft# PEAK advantage (read: off that peak the advantage was much less!). In the last years of LT1/4 production (I wanna say beginning in 1994?) torque was bumped to 340 peak (due to improved cam profile and better catalytic converters) which pretty much put peak torque on parity with the L98s, and far superior considering the flatness of the torque curve in addition to the width (rpm range).

Taking nothing away from the fun of driving the L98 cars - especially on the street - the torque curve of the late LT1s (especially) and the LT4s is such that drivability is very much better over nearly the entire rpm range than the L98. The good news is the L98 is a 350 too, and it responds well to the plethora of aftermarket cams, intakes and exhaust systems if you ever want to beef up the torque curve beyond it's current 4500 (or so) rpm - part of the fun of the SBC especially!

Course, there IS another C4 option...one that puts as much torque to the rear wheels in stock form as the LT1/4s do at the flywheel...one that can be increased by 90 to 100 ft# more yet at the wheels with only porting and exhausts... Spend wisely!

 

IMHO, pick the years where you like the exterior and interior styling and make sure the gear is 3.07 or numerically higher. Any C4 with a good ratio is going to be fast and fun.

If modding is going to be something you want to do to the engine I would do a 86-91 over the LT-1, just a personal opinion.

 

My advice is...
Drive a few L98 cars and a few LT1 cars. Use your own butt dyno to see what you like! Both have their + and -, see what you can live with and what you love about each.


Me personally, I love the 84-90 styling and the 95-96 running gear.

 

My 89 L98 Vette with the 3:07 rear, felt a lot quicker than my 91 L98 Vette with the 2:59 rear!...

 

I had an 86 with the 4+3 and now have a 95 auto. The difference is about 60hp which is about 20%, which to me is very noticeable. As some have alluded to, for just driving around town punching it now and then, they will both do fine, but when I'm getting on the highway and the rpms get up to about 4k where the L98 starts dying, the LT1 starts to really sing. In addition, I know it wasn't part of your original question, but the LT1 is just a nicer running motor. It just seems a lot smoother.

But of course you will pay more for an equivalent condition/mileage LT1 car, so if you are limited on funds, you basically get a nicer condition L98 car for the same money.

 

Seat of the pants? Probably not much if any noticeable difference. In fact, and early car with a low gear will probably FEEL faster than a later car w/a crappy tall gear (although it won't be faster).

CLIFF NOTES:
Handling: early cars w/the Z51 produce the best handling numbers...ride the worst.

Power:
Later cars are faster, hands down. Doesn't matter what the tq curve is, they make more hp and they are faster.

Braking;
Later cars have bigger/better brakes

What does all of this mean on the STREET? Nothing. Drive a bunch, buy the car that suits YOU, the best.

 

If I were buying again today, I would look at 1993 and above years.

 

One more thing--the L98 era had ever changing engines. There were lots of changes in the between 1986 and 1990. '90-'91 had speed density, aluminum 113 heads, and higher compression compared to a 1985 for instance. At any rate both are based from the SBC and can be made into pretty much any power package.

I would take any year C4. The early ones have the classic SBC DNA built into them, but less power. LT1's have a few tricks to get 50 HP more , but the opti-spark instead of the tried and true distributor. IMO, the best SBC derived engine is the LT4 of course. I really wanted one of these, but by '96 it looks like all the old geezers buying c4's went with the auto and I couldn't find one when I was Vette shopping that wasn't a Grand Sport.

A high mileage garage kept early C4 is so cheap and easy to find that the 383 beast possibility can be pulled off for small money.