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

sequential ??

Thread Tools
 
Search this Thread
 
Old Dec 25, 2006 | 08:01 PM
  #1  
gator79's Avatar
gator79
Thread Starter
Safety Car
15 Year Member
 
Joined: May 2005
Posts: 4,176
Likes: 7
From: Jennings LA
Default sequential ??

I have a '93 how can I tell if it sequential injection?
Reply
Old Dec 25, 2006 | 08:02 PM
  #2  
STL94LT1's Avatar
STL94LT1
Race Director
20 Year Member
Conversation Starter
All Eyes On Me
Liked
 
Joined: Jan 2002
Posts: 12,261
Likes: 85
From: O'Fallon Missouri
Default

It's not sequential, that started in 94.
Reply
Old Dec 25, 2006 | 08:14 PM
  #3  
gator79's Avatar
gator79
Thread Starter
Safety Car
15 Year Member
 
Joined: May 2005
Posts: 4,176
Likes: 7
From: Jennings LA
Default

i heard some late '93s were sequential
Reply
Old Dec 25, 2006 | 08:16 PM
  #4  
STL94LT1's Avatar
STL94LT1
Race Director
20 Year Member
Conversation Starter
All Eyes On Me
Liked
 
Joined: Jan 2002
Posts: 12,261
Likes: 85
From: O'Fallon Missouri
Default

Check your fuel rails. I'm pretty sure all sequentials had a cross-over.
Reply
Old Dec 25, 2006 | 08:17 PM
  #5  
Mr Mojo's Avatar
Mr Mojo
Elite Torch Red Member
Supporting Lifetime Gold
25 Year Member
 
Joined: Sep 1999
Posts: 57,805
Likes: 23
From: Exit 89 GSP,Lakewood,NJ The Land Of Mojo
Cental/South NJ Events Coordinator
CI 1-2-3-4-5-6-7-8-9-10-11-12 Vet
CI-II Burnout & Drag Champ
St. Jude Donor '03-'04-'05-'06-'07
Default

Originally Posted by gator79
i heard some late '93s were sequential
I'm just taking a guess here, but supposedly some '93's came with the later style transmission(4L60E rather than the 4L60) in which case you would have the silver PCM rather than the black ECM, nobody has any concrete evidence that this is true, my guess is also it would have the MAF as well since that came in '94.
Also teh intake manifold would have a crossover tube.

But like I said, it's only a guess and probably wrong.
Reply
Old Dec 25, 2006 | 08:37 PM
  #6  
gator79's Avatar
gator79
Thread Starter
Safety Car
15 Year Member
 
Joined: May 2005
Posts: 4,176
Likes: 7
From: Jennings LA
Default

the '93 FSM states seqquential fuel injection vin J, what space would that be in the vin?
Reply
Old Dec 25, 2006 | 09:03 PM
  #7  
zr1fred's Avatar
zr1fred
Race Director
15 Year Member
Veteran: Marine Corps
All Eyes On Me
Top Answer: 1
 
Joined: May 2006
Posts: 10,691
Likes: 71
From: Phoenix Arizona
Default

That would be a LT-5 (ZR-1) Eighth digit.

Last edited by zr1fred; Dec 25, 2006 at 09:07 PM.
Reply
Old Dec 25, 2006 | 09:15 PM
  #8  
gator79's Avatar
gator79
Thread Starter
Safety Car
15 Year Member
 
Joined: May 2005
Posts: 4,176
Likes: 7
From: Jennings LA
Default

just checked my vin no J
I would know if I had a ZR1,I was just hoping for sequential injection. looks like mine is batch fired
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

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

 Michael S. Palmer
story-1

2027 Corvette vs The World: Every Model vs Closest Competitor

 Joe Kucinski
story-2

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
story-3

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

 Joe Kucinski
story-4

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

 Joe Kucinski
story-5

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

 Joe Kucinski
story-6

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

 Brett Foote
story-7

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

 Joe Kucinski
story-8

Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!

 Michael S. Palmer
story-9

5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!

 Joe Kucinski
Old Dec 25, 2006 | 09:32 PM
  #9  
RRT vette's Avatar
RRT vette
Le Mans Master
15 Year Member
 
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Default

I would say you have batch fire.
Reply
Old Dec 25, 2006 | 09:36 PM
  #10  
STL94LT1's Avatar
STL94LT1
Race Director
20 Year Member
Conversation Starter
All Eyes On Me
Liked
 
Joined: Jan 2002
Posts: 12,261
Likes: 85
From: O'Fallon Missouri
Default

Originally Posted by gator79
just checked my vin no J
My 94 with SFI is VIN P.
Reply
Old Dec 25, 2006 | 09:43 PM
  #11  
RRT vette's Avatar
RRT vette
Le Mans Master
15 Year Member
 
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Default

Originally Posted by STL94LT1
My 94 with SFI is VIN P.
So does my 95.
Reply
Old Dec 25, 2006 | 09:57 PM
  #12  
gator79's Avatar
gator79
Thread Starter
Safety Car
15 Year Member
 
Joined: May 2005
Posts: 4,176
Likes: 7
From: Jennings LA
Default

mine is vin P also, I was just going by the '93 FSM and it states vin J as sequential multiport but that must be the ZR1
Reply
Old Dec 25, 2006 | 10:03 PM
  #13  
MikeC4's Avatar
MikeC4
Melting Slicks
 
Joined: Oct 2004
Posts: 2,510
Likes: 4
From: Austin Texas
Default

Originally Posted by RRT vette
I would say you have batch fire.
What exactly is "batch" fire? I am sensing fuel in-efficiancy here...... I have a '93

Reply
Old Dec 25, 2006 | 10:13 PM
  #14  
RRT vette's Avatar
RRT vette
Le Mans Master
15 Year Member
 
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Default

Sequential (multi port)- each injector fires individually in firing sequence.

Batch - a bank/batch of injectors fire together (all injectors fire in one batch). One side fires then the other side.
Reply
Old Dec 25, 2006 | 11:15 PM
  #15  
pcolt94's Avatar
pcolt94
Le Mans Master
15 Year Member
 
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
Default

My Tech 1 will not select SFI for a 93, only a 94 and up. The 93 comes up MFI.

What’s interesting is if I select the fuel system for a 94 by VIN number, it selects SFI . But if I select fuel manually by menu it comes up as MFI. Not sure if menu selection and operation is same for both, have never explored that difference. I always select by VIN, P, eighth digit
Reply
Old Dec 26, 2006 | 12:29 AM
  #16  
comp's Avatar
comp
Team Owner
10 Year Member
 
Joined: Sep 2003
Posts: 88,393
Likes: 2
From: eville in
Default

Reply
Old Dec 26, 2006 | 02:33 AM
  #17  
tjwong's Avatar
tjwong
Le Mans Master
Supporting Lifetime Gold
20 Year Member
 
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
Default

All 92 and 93 Y and 93 F body used the same ECM and they are both batch fire. SEFI was not introduced until the PCM hardware change in 1994. Also in 1994 the MAF sensor returned for better emissions control. The only basic difference between the older speed density batch fire cars was that they didn't have the more precise fuel control of the MAF strategy cars. However performance numbers and power ratings were basically the same. There really isn't any significant power gains between the two strategies. The main benefit is that SEFI offers some more tunability as one can trim fuel to individual cylinders. So that means it can offer slightly better tuning abilities when larger cams are used. A MAF strategy is also a bit more forgiving with engine mods. Which means tuning one is a bit easier than a SD car. But that ends if a very large cam is installed.
Reply

Get notified of new replies

To sequential ??

Old Dec 26, 2006 | 12:14 PM
  #18  
zr1fred's Avatar
zr1fred
Race Director
15 Year Member
Veteran: Marine Corps
All Eyes On Me
Top Answer: 1
 
Joined: May 2006
Posts: 10,691
Likes: 71
From: Phoenix Arizona
Default

GREAT explanation!
Reply
Old Dec 26, 2006 | 12:16 PM
  #19  
Casethecorvetteman's Avatar
Casethecorvetteman
Le Mans Master
20 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Default

Originally Posted by gator79
mine is vin P also, I was just going by the '93 FSM and it states vin J as sequential multiport but that must be the ZR1
It is. The LT5 in the ZR1 has SEFI. Your 93 LT1 does not. No late 93s had SEFI or 4L60-Es, they were early 94s.

For every one person that says late 93 cars had the 4L60-E, there is another 1 that says the first run of 94s only had 4L60s. Neither one of them can prove either statement to be a fact.
Reply
Old Dec 26, 2006 | 01:01 PM
  #20  
bogus's Avatar
bogus
Team Owner
25 Year Member
Conversation Starter
All Eyes On Me
Liked
 
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
Default

Originally Posted by tjwong
All 92 and 93 Y and 93 F body used the same ECM and they are both batch fire. SEFI was not introduced until the PCM hardware change in 1994. Also in 1994 the MAF sensor returned for better emissions control. The only basic difference between the older speed density batch fire cars was that they didn't have the more precise fuel control of the MAF strategy cars. However performance numbers and power ratings were basically the same. There really isn't any significant power gains between the two strategies. The main benefit is that SEFI offers some more tunability as one can trim fuel to individual cylinders. So that means it can offer slightly better tuning abilities when larger cams are used. A MAF strategy is also a bit more forgiving with engine mods. Which means tuning one is a bit easier than a SD car. But that ends if a very large cam is installed.
The real advantage to SFI is economy. The MPFI maxes at about 26mpg highway, whereas the SFI will top 30 on the highway.
Reply



All times are GMT -4. The time now is 12:19 PM.

story-0
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-1
2027 Corvette vs The World: Every Model vs Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-20 17:58:41


VIEW MORE
story-2
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-3
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-4
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-5
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-6
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-7
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
story-8
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!

Slideshow: Breaking down the 2027 Grand Sport, Grand Sport X, Stingray, and LS6 V8.

By Michael S. Palmer | 2026-03-26 13:48:45


VIEW MORE
story-9
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!

Slideshow: 5 reasons bad drivers crash sports cars & 5 ways to avoid a costly shame!

By Joe Kucinski | 2026-03-25 16:32:55


VIEW MORE