C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

what does LT1 mean?

Thread Tools
 
Search this Thread
 
Old Jun 8, 2009 | 09:57 PM
  #21  
65MalibuSS's Avatar
65MalibuSS
Intermediate
20 Year Member
All Eyes On Me
 
Joined: Jun 2005
Posts: 48
Likes: 1
Default

Originally Posted by No Go
The early LT-1 generation was the most powerful SBC...until the LT1 (Gen III) arrived.

This is true in HP and TQ...remember early was gross HP ratings (360/370) and the modern is a far more conservative number/calculation.
LT1 = Gen II

And you are correct.
Take away all the plastic intake crap, maf, catalytic converters, mufflers, emissions stuff, install dual plane intake, carburetor, open headers, and the Gen II LT will make more like 380-400 gross HP.
Which is exactly what I'm installing in my dragster, except I'm adding an LT4 "hot cam".
Reply
Old Jun 8, 2009 | 10:45 PM
  #22  
biggrizzly's Avatar
biggrizzly
Melting Slicks
15 Year Member
 
Joined: Jun 2002
Posts: 2,705
Likes: 30
From: Chesapeake Beach Maryland
2015 C5 of Year Finalist
Default

A significant feature of the LT1 that I think has been missed here is the reverse flow cooling system of the late LT1 and LT4 engines. By reversing the coolant to cool the heads first before the engine block, the engineers were able to increase the compression while keeping detonation down due to cooler combustion temps. This was the single most important technical advance that the LT1 had over all previous small blocks.
Reply
Old Jun 9, 2009 | 05:28 AM
  #23  
No Go's Avatar
No Go
Melting Slicks
25 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Jun 2000
Posts: 3,215
Likes: 6
From: Tampa Florida
Default

65MalibuSS: Right you are...one too many I's in Gen II.
Reply
Old Jun 9, 2009 | 09:28 AM
  #24  
TorchRedlt4man's Avatar
TorchRedlt4man
Drifting
20 Year Member
All Eyes On Me
Photogenic
Liked
 
Joined: May 2005
Posts: 1,336
Likes: 12
From: Chicago Executive Airport, formerly known as Palwaukee
No-IL Events Coordinator
St. Jude Donor '12-'13-'14-'15-'16-'17
Default

Originally Posted by biggrizzly
A significant feature of the LT1 that I think has been missed here is the reverse flow cooling system of the late LT1 and LT4 engines. By reversing the coolant to cool the heads first before the engine block, the engineers were able to increase the compression while keeping detonation down due to cooler combustion temps. This was the single most important technical advance that the LT1 had over all previous small blocks.
You are so right! A lot of folks are not aware of the reverse flow cooling system. I believe this system is the reason why so many LT1s and LT4s are accumulating so many miles!

When I spoke to Dave McLellan a few years ago, he told me the LT5 had some features of reverse flow cooling. They incorporated those features and added more into the LTx series. He said the cooling system of the LT5 is one of the reasons why that engine is practically bullet-proof even though it is incredibly complex.

SAVE THE WAVE!
Reply
Old Jun 9, 2009 | 10:42 AM
  #25  
josephf31's Avatar
josephf31
Pro
10 Year Member
 
Joined: Mar 2008
Posts: 579
Likes: 2
From: High Bridge New Jersey
Default Yup

Originally Posted by MK 82
L98 to LT1 is more than induction hardware. 90 is an L98.
exactamundo; it's still a Chevy small block but many other things changed besides just the induction...
Reply
Old Jun 9, 2009 | 10:44 AM
  #26  
josephf31's Avatar
josephf31
Pro
10 Year Member
 
Joined: Mar 2008
Posts: 579
Likes: 2
From: High Bridge New Jersey
Default Than

Originally Posted by reoch999
Than???
than the L98 motor
Reply
Old Jun 9, 2009 | 01:31 PM
  #27  
bowtie350_428's Avatar
bowtie350_428
Pro
15 Year Member
 
Joined: May 2005
Posts: 525
Likes: 0
From: San Antonio TX
Default

Originally Posted by new 90 vette
My new(for me) 90 convertible has "Lingenfelter Performance Engineering" across the windshield and LT1 with a Corvette symbol on the rear. What does LT1 mean and does "Lingenfelter" have anything to do with it.
Tnanks,
Earl
It means you'll have fun messing with the Opti-Spark. That is if you had one. The 90 is an L98 so you don't have one.

The stickers probably means the previous owner was just "Sticker happy" from wishful thinking.
Reply
Old Jun 9, 2009 | 01:50 PM
  #28  
tpivette's Avatar
tpivette
Pro
20 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Jan 2003
Posts: 515
Likes: 3
From: newark DE
Default

Originally Posted by cumbercr
LT = Less Torque
hmmm... my bone stock LT1 dynoed 306rwtq. doing the 15% drivetrain loss (it was a manual) puts it at 360ftlbs at the flywheel. so these motors had just as much or more than a L98
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-1

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-2

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-3

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-4

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-5

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-6

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-7

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-8

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-9

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
Old Jun 9, 2009 | 02:00 PM
  #29  
65MalibuSS's Avatar
65MalibuSS
Intermediate
20 Year Member
All Eyes On Me
 
Joined: Jun 2005
Posts: 48
Likes: 1
Default

Originally Posted by tpivette
hmmm... my bone stock LT1 dynoed 306rwtq. doing the 15% drivetrain loss (it was a manual) puts it at 360ftlbs at the flywheel. so these motors had just as much or more than a L98
I think cumbercr was just joking.
But I could be wrong.
Reply
Old Jun 9, 2009 | 02:44 PM
  #30  
94ZR1's Avatar
94ZR1
Le Mans Master
 
Joined: Aug 2005
Posts: 5,002
Likes: 5
From: No Opti Here Tn
St. Jude Donor '06
Default

In 1990 all Corvettes had L98 engines
Yours may or may not have any Lingenfelter parts on it and it is definitely not an LT1 unless it was swapped out otherwise its just stickers
Lt1 was not the only engine from 91-96, LT5 an LT4 were also used
There is so much disinformation in this thread I forgot the rest of it
Reply
Old Jun 9, 2009 | 07:45 PM
  #31  
BAM92's Avatar
BAM92
Safety Car
15 Year Member
 
Joined: May 2003
Posts: 4,283
Likes: 0
From: Houston Texas
Default

Originally Posted by 94ZR1
In 1990 all Corvettes had L98 engines
Yours may or may not have any Lingenfelter parts on it and it is definitely not an LT1 unless it was swapped out otherwise its just stickers
Lt1 was not the only engine from 91-96, LT5 an LT4 were also used
There is so much disinformation in this thread I forgot the rest of it
Not all 1990 Corvettes had L98's. Quite a few had LT5's. And no 91's came with a LT1. They were still using L98's.

Last edited by BAM92; Jun 9, 2009 at 07:47 PM.
Reply
Old Jun 10, 2009 | 11:21 AM
  #32  
josephf31's Avatar
josephf31
Pro
10 Year Member
 
Joined: Mar 2008
Posts: 579
Likes: 2
From: High Bridge New Jersey
Default No joke

Originally Posted by 65MalibuSS
I think cumbercr was just joking.
But I could be wrong.
It's pretty much common knowledge that the L98 is a torquier motor than the LT-1
Reply
Old Jun 10, 2009 | 12:56 PM
  #33  
onedef92's Avatar
onedef92
Team Owner
20 Year Member
 
Joined: Oct 2000
Posts: 96,443
Likes: 9
From: Fort Knox, KY
Cruise-In IV Veteran
Cruise-In VI Veteran
Cruise-In VII Veteran
Cruise-In VIII Veteran
Default

Originally Posted by TorchRedlt4man
You are so right! A lot of folks are not aware of the reverse flow cooling system. I believe this system is the reason why so many LT1s and LT4s are accumulating so many miles!

When I spoke to Dave McLellan a few years ago, he told me the LT5 had some features of reverse flow cooling. They incorporated those features and added more into the LTx series. He said the cooling system of the LT5 is one of the reasons why that engine is practically bullet-proof even though it is incredibly complex.

SAVE THE WAVE!
Another significant (albeit highly maligned and controversial technical advance) was the introduction of the Optispark Module on the LT1 and LT4 engines.


http://www.gmhightechperformance.com...ing/index.html
Reply
Old Jun 10, 2009 | 02:17 PM
  #34  
rickneworleansla's Avatar
rickneworleansla
Le Mans Master
15 Year Member
 
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
Default

Originally Posted by josephf31
It's pretty much common knowledge that the L98 is a torquier motor than the LT-1
EnginePeak HP @ RPM Peak Torque @ RPM
------ ------------- -----------------
L98 250 @ 4000 340 @ 3200

LT1 300 @ 5000 340 @ 3600


...although the curve may look different.
Reply
Old Jun 10, 2009 | 02:46 PM
  #35  
PLRX's Avatar
PLRX
Team Owner
 
Joined: Aug 2005
Posts: 34,988
Likes: 515
From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
2018 Corvette of Year Finalist
2017 C4 of Year
2016 C7 of Year Finalist
St. Jude Donor '09 thru '20
Default

How much HP % do I loose with an automatic and 3.07 axle?
Reply
Old Jun 10, 2009 | 09:37 PM
  #36  
Aurora40's Avatar
Aurora40
Le Mans Master
10 Year Member
 
Joined: Apr 2005
Posts: 6,413
Likes: 9
From: The Old Dominion
Default

Originally Posted by rickreeves1
EnginePeak HP @ RPM Peak Torque @ RPM
------ ------------- -----------------
L98 250 @ 4000 340 @ 3200

LT1 300 @ 5000 340 @ 3600


...although the curve may look different.
FYI, the L98 was rated as high as 350lb-ft for some years/trims. I believe both the L98 and LT1 were rated as low as 330lb-ft for some years.
Reply
Old Jun 10, 2009 | 10:01 PM
  #37  
rickneworleansla's Avatar
rickneworleansla
Le Mans Master
15 Year Member
 
Joined: Aug 2004
Posts: 5,141
Likes: 7
From: Metairie Louisiana
Default

Originally Posted by Aurora40
FYI, the L98 was rated as high as 350lb-ft for some years/trims. I believe both the L98 and LT1 were rated as low as 330lb-ft for some years.
Reply

Get notified of new replies

To what does LT1 mean?

Old Jun 11, 2009 | 03:04 AM
  #38  
BAM92's Avatar
BAM92
Safety Car
15 Year Member
 
Joined: May 2003
Posts: 4,283
Likes: 0
From: Houston Texas
Default

92 Lt1 was 330 and 93-96 Vette LT1's were 340.
Reply
Old Jun 11, 2009 | 03:57 AM
  #39  
cv67's Avatar
cv67
Team Owner
15 Year Member
 
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Default

LT1 did not make 400chp.
Reply
Old Jun 11, 2009 | 09:51 AM
  #40  
ffvetteman's Avatar
ffvetteman
Drifting
10 Year Member
 
Joined: Aug 2003
Posts: 1,565
Likes: 2
From: somewhere between heaven and hell WI
Default

Originally Posted by BAM92
92 Lt1 was 330 and 93-96 Vette LT1's were 340.
All LT1's were 300hp and LT4's were 330hp.
Reply




All times are GMT -4. The time now is 07:09 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE