LT4vs.LT5
Le Mans Master
Joined: May 2004
Posts: 5,386
Likes: 534
This is personal opinion, but if the LT-4 had to excel past the LT-5 in any area, that area may be it's being mechanically simpler. By that I mean, you can fool around with an LT-4/LT-1/L-83/L-98 in your garage and feel pretty confident in what you're doing if you take time to read up on the manuals. However, I notice not too many people advise tackling major repairs on an LT-5 in your own garage. Though some of these ZR-1 pros on this site could prove me wrong. Other than the simplicity of the pushrod setup, and perhaps broader availability of parts, I would say these are the only two factors where an LT-4 comes out on top. Performance wise, an LT-4 is nothing and never will be anything to sneeze at.
Le Mans Master
Joined: Apr 2000
Posts: 5,589
Likes: 0
From: DrunkDefender
CI 1-2-3-4-5-6-7-8 Veteran
CI-IV AutoX Champ
CI-IV Burnout Champ
St. Jude Donor '07-'10
Todd!!! havent seen you around in a while. Where have you been hiding at?
Back on topic, I had a 90 L98 6 speed. I wanted a zed but couldnt find one I could afford. I ended up with an LT4 with 50k on the clock. I'm happy so far and it is an easier design to work on but there cant be too much on a zed that would scare me anyways. I'd like to have one of each if I could. FWIW, mine put down 316 rwhp stock from the air cleaner to the exhaust tips on its best pull but it usually put down an average of 305-310rwhp. Once you start modding its about who has the deepest pockets. Intrestingly enough niether of the two cars in question can compete againt an 89 - 91 Z51/zo7 6speed cars in solo2 events and the Zed has never been very competetive in that arena due to the extra weight.
Back on topic, I had a 90 L98 6 speed. I wanted a zed but couldnt find one I could afford. I ended up with an LT4 with 50k on the clock. I'm happy so far and it is an easier design to work on but there cant be too much on a zed that would scare me anyways. I'd like to have one of each if I could. FWIW, mine put down 316 rwhp stock from the air cleaner to the exhaust tips on its best pull but it usually put down an average of 305-310rwhp. Once you start modding its about who has the deepest pockets. Intrestingly enough niether of the two cars in question can compete againt an 89 - 91 Z51/zo7 6speed cars in solo2 events and the Zed has never been very competetive in that arena due to the extra weight.
Le Mans Master
Joined: Apr 2000
Posts: 5,589
Likes: 0
From: DrunkDefender
CI 1-2-3-4-5-6-7-8 Veteran
CI-IV AutoX Champ
CI-IV Burnout Champ
St. Jude Donor '07-'10
Originally Posted by 1985 Corvette
Performance wise, an LT-4 is nothing and never will be anything to sneeze at.
Le Mans Master
Joined: May 2004
Posts: 5,386
Likes: 534
Originally Posted by Dr. Evil
Compared to what?
I think you misunderstood my post. "nothing to sneeze at" means nothing to complain about, meaning it's a very good thing. That's what I meant. The LT-4 is a tremendous performance engine as long as you're not spoiled by opening up today's car magazines and seeing horsepower climing into the 600's. Don't worry Evil, you'll never catch me tearing down any high performance Chevy smallblock in a negative way, guaranteed!
Red96Coupe: Did I read that right? I seriously had to do a double take on your performance specs in the quarter. It's sounds too good to be true. You sure your LT-1 isn't one of those rare test cars that Car and Driver/MotorTrend used to get their hands on back in the early days?
I'm so used to hearing 101-103 for an LT-1 and then I pick up a back issue of a car magazine where they manage to squeeze out 107mph and my jaw just drops.
Last edited by 1985 Corvette; May 20, 2005 at 12:53 AM.
Race Director
Joined: May 2003
Posts: 10,749
Likes: 41
Originally Posted by vette&f-bod lover
ok,havent seen a thread like this in a while,here's the scenario,96 LT4vs.95 ZR1,little bro,vs.big bro,at the dragstrip,and the dyno.both cars bone stock.although I never saw head to head,same day,etc.did some research,heres what I found,its all hypothetical and for fun for those who've always wanted to know,which was quicker
96 LT4
60ft 1.93
1/8mile 8.3@86mph
1/4mile 12.9@108mph
302 RWHP
299 RWTQ
95 ZR1
60ft 2.08
1/8mile 8.2@88mph
1/4mile 12.8@112mph
347 RWHP
338 RWTQ
LT4 pulls out better,but ZR1 catches it by 50 mph(0-60 for LT4 is 4.7,ZR1 is 4.5)then 32 valves kick in,and by the 1/8 its ahead,and nips it by the 1/4.who has some realworld experience between the 2?
96 LT4
60ft 1.93
1/8mile 8.3@86mph
1/4mile 12.9@108mph
302 RWHP
299 RWTQ
95 ZR1
60ft 2.08
1/8mile 8.2@88mph
1/4mile 12.8@112mph
347 RWHP
338 RWTQ
LT4 pulls out better,but ZR1 catches it by 50 mph(0-60 for LT4 is 4.7,ZR1 is 4.5)then 32 valves kick in,and by the 1/8 its ahead,and nips it by the 1/4.who has some realworld experience between the 2?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Le Mans Master
Joined: Apr 2000
Posts: 5,589
Likes: 0
From: DrunkDefender
CI 1-2-3-4-5-6-7-8 Veteran
CI-IV AutoX Champ
CI-IV Burnout Champ
St. Jude Donor '07-'10
1985Corvette, just checking 
I'm well aware of the potential for every motor used in the C4 platform. I have yet to drive a zed in anger but have driven everything else including Zo6's and such. From a pure fun factor standpoint a well tuned L98 is as much fun to drive as anything.
Also, Red96Coupe has been around a while. He and another member MackeyRed96 put their respective 96 LT1s deep into the 12s. For a while it was a contest that most all of C4 gen/tech was following and then there is Beach Bum who put his L98 car in the mid 11s. Those are 3 of the most knowlegeable drag racers in the c4 section right there.
I'm well aware of the potential for every motor used in the C4 platform. I have yet to drive a zed in anger but have driven everything else including Zo6's and such. From a pure fun factor standpoint a well tuned L98 is as much fun to drive as anything.
Also, Red96Coupe has been around a while. He and another member MackeyRed96 put their respective 96 LT1s deep into the 12s. For a while it was a contest that most all of C4 gen/tech was following and then there is Beach Bum who put his L98 car in the mid 11s. Those are 3 of the most knowlegeable drag racers in the c4 section right there.
Thread Starter
Burning Brakes
Joined: Mar 2005
Posts: 1,042
Likes: 0
wow,I didnt mean to start a 
between the 2,because I love em both,and anyone to bash either 1 is 
it was meant more for a comparison,but heres my take on the 2 having driven both.driving the LT4 around town,it has better throttle response,a little more low end torque,etc.you'd swaer it'd kick a ZR1's butt,kinda like driving an L98 compared to a LT1.however,once you get into the throttle and RPM's,those DOHC's kick in with a WHOOSH 
out on the highway,its a different story.LT5 feels like it's 50 cubes bigger compared to LT4.if I had the choice,straight up,if I had unlimited funds,i'd have a ZR1,best looking corvette engine in history,period.love that "power key",and wide "butt".it will also hold its value better.(non GS)also,even today,people(most)know what a ZR1 was.it will always have that "mystique".cant say the same about an LT4.if you want a collector,ZR1 is the better choice.however,right now good/used LT4's are under $20k,94-95 ZR1's under $30k.thats plenty of money left over to destroy a Z in a kind of speed contest.just a hotcam,PCM tune,& catback will do that(track/street).love em both,but unless I win the Lottery,i'll take a LT4 drop top with light mods,and have the best of both worlds 
between the 2,because I love em both,and anyone to bash either 1 is it was meant more for a comparison,but heres my take on the 2 having driven both.driving the LT4 around town,it has better throttle response,a little more low end torque,etc.you'd swaer it'd kick a ZR1's butt,kinda like driving an L98 compared to a LT1.however,once you get into the throttle and RPM's,those DOHC's kick in with a WHOOSH out on the highway,its a different story.LT5 feels like it's 50 cubes bigger compared to LT4.if I had the choice,straight up,if I had unlimited funds,i'd have a ZR1,best looking corvette engine in history,period.love that "power key",and wide "butt".it will also hold its value better.(non GS)also,even today,people(most)know what a ZR1 was.it will always have that "mystique".cant say the same about an LT4.if you want a collector,ZR1 is the better choice.however,right now good/used LT4's are under $20k,94-95 ZR1's under $30k.thats plenty of money left over to destroy a Z in a kind of speed contest.just a hotcam,PCM tune,& catback will do that(track/street).love em both,but unless I win the Lottery,i'll take a LT4 drop top with light mods,and have the best of both worlds
Last edited by vette&f-bod lover; May 21, 2005 at 05:29 PM.
Team Owner
Joined: Aug 2000
Posts: 24,125
Likes: 3
St. Jude Donor '14
Originally Posted by vette&f-bod lover
however,right now good/used LT4's are under $20k,94-95 ZR1's under $30k.thats plenty of money left over to destroy a Z in a kind of speed contest.just a hotcam,PCM tune,& catback will do that.love em both,but unless I win the Lottery,i'll take a LT4 drop top with light mods,and have the best of both worlds
Here's another fact. As soon as you start modifying a car, the value of that car takes a dump, not only that, but you will never recover all the cash you put into it. And then there's the headaches that come with getting the tunning right. The best bang for the buck right now is a ZR1. But that won't last for ever.
Thread Starter
Burning Brakes
Joined: Mar 2005
Posts: 1,042
Likes: 0
Originally Posted by 8388
By highly modded, I mean alot more than you mentioned.
Team Owner
Joined: Aug 2000
Posts: 24,125
Likes: 3
St. Jude Donor '14
Originally Posted by vette&f-bod lover
your right,the mods I mentioned,I meant @ the track/street(roll ons).I should have clarified that.btw,a ported head/cam/exhaust/tune LT4 will put out over 380 horse @ the wheels,thats enough to take a Z on the top end.You say your buddy couldnt outrun you,but is your car totally stock?
Instructor
Joined: Sep 2004
Posts: 153
Likes: 0
I have been doing track days with my stock LT4 for many years. Over that time I have come across several ZR1's. On the track, the LT5 always seems to pull a couple of car lengths on me down the straights. It's a strong motor. I would rate them it very similar to the Z06's I come across.
Unlike the Z06's and my LT4, the ZR1's seem to have a little trouble in the twisty bits. I don't know if it is the extra weight of that motor up front or what, but they just don't seem to turn as well as the LT4.
My experience with LS1 C5's is that they are about dead even power wise to the LT4, Speed on the straight is more dependent on who got the better drive out of the corner.
Cheers,
Lawrence
Unlike the Z06's and my LT4, the ZR1's seem to have a little trouble in the twisty bits. I don't know if it is the extra weight of that motor up front or what, but they just don't seem to turn as well as the LT4.
My experience with LS1 C5's is that they are about dead even power wise to the LT4, Speed on the straight is more dependent on who got the better drive out of the corner.
Cheers,
Lawrence
Le Mans Master
Joined: Nov 2000
Posts: 8,277
Likes: 0
From: pa
Originally Posted by 1985 Corvette
This is personal opinion, but if the LT-4 had to excel past the LT-5 in any area, that area may be it's being mechanically simpler. By that I mean, you can fool around with an LT-4/LT-1/L-83/L-98 in your garage and feel pretty confident in what you're doing if you take time to read up on the manuals. However, I notice not too many people advise tackling major repairs on an LT-5 in your own garage. Though some of these ZR-1 pros on this site could prove me wrong. Other than the simplicity of the pushrod setup, and perhaps broader availability of parts, I would say these are the only two factors where an LT-4 comes out on top. Performance wise, an LT-4 is nothing and never will be anything to sneeze at.
That being said I remember seeing, a few years ago at bowling green, a few ZR-1 vs GS's. While the race was close for about the first 330 feet the ZR-1 walked away after that, not by a lot but by enough. On the street the difference is even more pronounced.
Last edited by 90 Corvette ZR-1; May 21, 2005 at 01:51 AM.
Race Director
Joined: Oct 2000
Posts: 14,064
Likes: 1,166
From: N. Alabama
Actually, one needs to define the parameters of better; collectible value? daily driver? top speed? dragstrip? ease of modifying performance upgrades? initial purchase? cost of maintenance?
I drive mine. They are no garage queens. I find the LT4 does very nicely for my purposes.
I drive mine. They are no garage queens. I find the LT4 does very nicely for my purposes.
Le Mans Master
Joined: Jul 1999
Posts: 8,683
Likes: 6
From: Phoenix AZ
Originally Posted by BDVETTE96
the last year of the ZR1's was 96, the only 405 hp version from the factory.