C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

LT-1 frame Vs Others

Thread Tools
 
Search this Thread
 
Old Jun 22, 2018 | 05:16 PM
  #1  
Micha's Avatar
Micha
Thread Starter
Instructor
 
Joined: Jun 2018
Posts: 131
Likes: 15
From: France
Default LT-1 frame Vs Others

Hi,

I'm quite new on your forum.
I'have a technical question :
I'm actively searching a 70 or 71 LT-1 or 454. And somebody told me that the LT-1 models have like a bar or an additionnal portion liked to the frame, on rear if my memory is good.

Now I've been told that some LT1 were fakes one just because they use to screw that bar to make the confusion, while the original piece was welded to the frame.
Any clues about this ?
Also if you have tips helping me to identify a real LT1 from fake ones I will buy it too !


Thank you.
Michael
Reply
Old Jun 22, 2018 | 05:23 PM
  #2  
derekderek's Avatar
derekderek
Race Director
 
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
Default

I believe that is a sway bar, not a piece welded to the frame.
Reply
Old Jun 22, 2018 | 05:24 PM
  #3  
20mercury's Avatar
20mercury
Safety Car
15 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2008
Posts: 3,746
Likes: 713
From: Lafayette Louisiana
Default Interesting.

Originally Posted by Micha
Hi,

I'm quite new on your forum.
I'have a technical question :
I'm actively searching a 70 or 71 LT-1 or 454. And somebody told me that the LT-1 models have like a bar or an additionnal portion liked to the frame, on rear if my memory is good.

Now I've been told that some LT1 were fakes one just because they use to screw that bar to make the confusion, while the original piece was welded to the frame.
Any clues about this ?
Also if you have tips helping me to identify a real LT1 from fake ones I will buy it too !


Thank you.
Michael
I have never heard of a bar, others on here more expert than me. Interesting to hear responses. I would think this bar would be in the AIM (assembly instruction manual for 72 Corvettes), but I have not seen that. I would guess aftermarket add.

Ah, Derek, and thanks, the "rear sway bar" and not welded for sure!

Here is a link to a LT-1 discussion, LT-1 attributes list at the bottom. (Wonder why I can not copy and paste anymore???)

Anyway, please go look in the General section here for a LT-1 discussion, should be still on the first page.

Good luck with the hunt!

Last edited by 20mercury; Jun 22, 2018 at 05:32 PM.
Reply
Old Jun 22, 2018 | 06:40 PM
  #4  
bashcraft's Avatar
bashcraft
Le Mans Master
20 Year Member
Active Streak: 30 Days
Active Streak: 60 Days
 
Joined: Jan 2006
Posts: 6,502
Likes: 138
From: Butler Pa
Default

The frame itself is the same regardless of the engine.
Reply
Old Jun 22, 2018 | 07:33 PM
  #5  
Crimson Thunder's Avatar
Crimson Thunder
Drifting
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Jun 2015
Posts: 1,325
Likes: 744
From: Doctors Inlet Florida
Default

Here is just a couple of ways to tell a real LT-1
1. Single fuel line with no return line
2. Half shafts mounted with caps instead of straps
3. 6500 redline tach
4. 4 speed only (no automatic)
Reply
Old Jun 22, 2018 | 08:10 PM
  #6  
F4Gary's Avatar
F4Gary
Race Director
Veteran: Air Force
25 Year Member
Liked
Community Favorite
 
Joined: Feb 2001
Posts: 11,053
Likes: 1,956
From: Grapevine Tx
2018 C3 of Year Finalist
2016 C3 of the Year Finalist
Default

I don't believe LT-1s came with a rear sway bar.
Reply
Old Jun 22, 2018 | 09:36 PM
  #7  
Gale Banks 80''s Avatar
Gale Banks 80'
Safety Car
15 Year Member
Photogenic
Photoriffic
Top Answer: 1
 
Joined: Nov 2008
Posts: 3,709
Likes: 550
From: Seattle Washington
Default

If your planning on getting into the Corvette hobby before purchasing a collectable car You should read as much as You can so when You go look at a car You know what to look for. "The Corvette Black book" is a good start and then " Corvette by the Numbers" will turn You into an expert once You have it memorized. And there are many more books to read as well.
Reply
Old Jun 22, 2018 | 09:41 PM
  #8  
LT1driver's Avatar
LT1driver
Le Mans Master
20 Year Member
 
Joined: Oct 2000
Posts: 6,209
Likes: 33
From: Texas-out west
Default

F4Gary is right LT-1 had no rear sway bar also front sway bar bigger than std 350
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-1

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-2

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-3

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
story-4

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
story-5

5 MOST and 5 LEAST Popular Corvette Model Years in History!

 Joe Kucinski
story-6

2027 Corvette Buyer's Guide: Everything You Need to Know!

 Joe Kucinski
story-7

10 Things C8 Corvette Owners Hate (But Won't Tell You)

 Joe Kucinski
story-8

10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

 Brett Foote
story-9

Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

 Joe Kucinski
Old Jun 23, 2018 | 07:40 AM
  #9  
Easy Mike's Avatar
Easy Mike
Team Owner
Supporting Lifetime
20 Year Member
 
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Default

Originally Posted by bashcraft
...The frame itself is the same regardless of the engine...
Correct. LT-1s used the regular production 4 speed frame.

Reply
Old Jun 23, 2018 | 11:42 AM
  #10  
3X2's Avatar
3X2
Melting Slicks
25 Year Member
Photogenic
Photoriffic
Top Answer: 1
 
Joined: Jan 2000
Posts: 3,321
Likes: 523
From: home
Default

I think the OP is referring to the two welded diagonal pieces at the rear kickups that were added starting in model year 1969.
Reply
Old Jun 23, 2018 | 11:45 AM
  #11  
Micha's Avatar
Micha
Thread Starter
Instructor
 
Joined: Jun 2018
Posts: 131
Likes: 15
From: France
Default

Thank you very much for your comments and useful information.
I'll dig further in the LT-1 Section.
Reply
Old Jun 23, 2018 | 03:30 PM
  #12  
The13Bats's Avatar
The13Bats
Race Director
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Mar 2003
Posts: 11,608
Likes: 778
From: Eustis ( Area 51 Bat Cave ) Fl
Default

So an LT 1 is like a bb car with a sb engine
Reply
Old Jun 23, 2018 | 04:01 PM
  #13  
dmaxx3500's Avatar
dmaxx3500
Team Owner
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jan 2008
Posts: 30,892
Likes: 1,189
From: chicago
Default

and ,I thought I read ,some LT1 car has auto trans and a/c at some point?
Reply
Old Jun 23, 2018 | 04:21 PM
  #14  
LT-1 kid's Avatar
LT-1 kid
Melting Slicks
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Sep 2007
Posts: 2,145
Likes: 283
From: cary Il
Default

Originally Posted by The13Bats
So an LT 1 is like a bb car with a sb engine
no, all SB including LT-1s had the small front sway bar, no rear sway bar, HD rear end caps, not HD diff though
basically all base motor cars and LT-1s suspension, frame, body, interior is all the same except for the rear diff caps, BB hood, motor option
Reply
Old Jun 23, 2018 | 05:01 PM
  #15  
derekderek's Avatar
derekderek
Race Director
 
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
Default

Micha. read the 10 rules sticky above. THEN, start doing homework on ways of verifying what you are looking at or for.
Reply
Old Jun 23, 2018 | 06:37 PM
  #16  
jb78L-82's Avatar
jb78L-82
Le Mans Master
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Oct 2007
Posts: 7,422
Likes: 955
From: Tennessee/Rhode Island
Default

The 71 LT-1 did not have a rear sway bar, only the BB C3's came with the 9/16 inch rear bar. The front SBC sway bar was 3/4 inch and the front BB sway bar was 15/16 inch. The front spring rate for the SB C3 in 71 was 250 lbs and 284lbs/inc for the BB-either way VERY soft compared to the later C3 with the gymkhana sport suspensions.

This is the major difference ^^^^^^ between BB and SBC C3's..the frames are all the same...there is no difference in the frames.

Everything you need or want to know about C3's by year is here:

https://www.gmheritagecenter.com/doc...t-Corvette.pdf

The later SBC C3's like my 78 with gymkhana suspension had 550 front springs/292lbs rear spring, 1 1/8 front sway bar and 7/16 rear sway bar as a comparator...you can see how much stiffer the later C3 cars versus even the early C3 BB cars were........It is funny that the early C3 cars had the power but usffered with the handling versus the later C3 SBC that could easily out handle the early C3's but had much less power

Last edited by jb78L-82; Jun 23, 2018 at 07:19 PM.
Reply
Old Jun 24, 2018 | 12:11 AM
  #17  
EarlyC34me's Avatar
EarlyC34me
Parts Sherpa
Supporting Lifetime
 
Joined: Feb 2017
Posts: 520
Likes: 98
From: ICE boneyard, Pa
Default

I believe what Michael is referring to and I may be wrong is the cross member is welded in and not removable on the lt-1 while others are removable. It seems like a lot of answers are describing suspension stuff but the question was about frame differences and that is the difference with the frame.
Michael please let us know what specifically you are trying to figure out.
Reply

Get notified of new replies

To LT-1 frame Vs Others

Old Jun 24, 2018 | 07:58 AM
  #18  
SS164's Avatar
SS164
Burning Brakes
20 Year Member
Photogenic
Photoriffic
Liked
 
Joined: Nov 2005
Posts: 1,062
Likes: 44
From: flemington n.j.
Default

All 4 speed cars leaving the factory had a welded in transmission crossmember regardless of whether the car was an LT1, BB, or base model. All Automatic transmission cars had a bolt in transmission crossmember. No rear sway bar on LT1. No automatic LT1's.
Reply
Old Jun 24, 2018 | 08:39 AM
  #19  
toylman's Avatar
toylman
Burning Brakes
15 Year Member
Veteran: Army
Liked
Community Favorite
 
Joined: Dec 2006
Posts: 977
Likes: 254
From: Bethlehem, PA
Default

Originally Posted by Micha
Hi,

I'm quite new on your forum.
I'have a technical question :
I'm actively searching a 70 or 71 LT-1 or 454. And somebody told me that the LT-1 models have like a bar or an additionnal portion liked to the frame, on rear if my memory is good.

Now I've been told that some LT1 were fakes one just because they use to screw that bar to make the confusion, while the original piece was welded to the frame.
Any clues about this ?
Also if you have tips helping me to identify a real LT1 from fake ones I will buy it too !


Thank you.
Michael
Restored pictures are a '70 LT1. Survivor pictures are a '72 454 car.






Reply
Old Jun 27, 2018 | 03:12 PM
  #20  
Micha's Avatar
Micha
Thread Starter
Instructor
 
Joined: Jun 2018
Posts: 131
Likes: 15
From: France
Default

Originally Posted by jb78L-82
The 71 LT-1 did not have a rear sway bar, only the BB C3's came with the 9/16 inch rear bar. The front SBC sway bar was 3/4 inch and the front BB sway bar was 15/16 inch. The front spring rate for the SB C3 in 71 was 250 lbs and 284lbs/inc for the BB-either way VERY soft compared to the later C3 with the gymkhana sport suspensions.

This is the major difference ^^^^^^ between BB and SBC C3's..the frames are all the same...there is no difference in the frames.

Everything you need or want to know about C3's by year is here:

https://www.gmheritagecenter.com/doc...t-Corvette.pdf

The later SBC C3's like my 78 with gymkhana suspension had 550 front springs/292lbs rear spring, 1 1/8 front sway bar and 7/16 rear sway bar as a comparator...you can see how much stiffer the later C3 cars versus even the early C3 BB cars were........It is funny that the early C3 cars had the power but usffered with the handling versus the later C3 SBC that could easily out handle the early C3's but had much less power
Thank you ! That a great attachment link you sent there. Very useful, as your comments. Thanks for contributing.

Reply



All times are GMT -4. The time now is 01:12 AM.

story-0
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-1
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-2
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-3
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-4
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE
story-5
5 MOST and 5 LEAST Popular Corvette Model Years in History!

Slideshow: 5 most and least popular Corvette model years.

By Joe Kucinski | 2026-04-08 13:25:01


VIEW MORE
story-6
2027 Corvette Buyer's Guide: Everything You Need to Know!

Slideshow: 2027 Corvette buyer's guide

By Joe Kucinski | 2026-04-17 16:41:08


VIEW MORE
story-7
10 Things C8 Corvette Owners Hate (But Won't Tell You)

Slideshow: 10 things C8 Corvette owners hate, but won't tell you.

By Joe Kucinski | 2026-04-01 18:36:07


VIEW MORE
story-8
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

Slideshow: Should you add one of these incredible Corvettes to your garage?

By Brett Foote | 2026-04-01 18:14:05


VIEW MORE
story-9
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

Slideshow: Every Corvette Grand Sport explained

By Joe Kucinski | 2026-03-26 07:13:44


VIEW MORE