LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Do i need a tune?

Thread Tools
 
Search this Thread
 
Old Jun 2, 2011 | 02:59 PM
  #1  
will1380's Avatar
Thread Starter
Staging Lane
 
Joined: Feb 2009
Posts: 99
Likes: 0
From: Kansas City MO
Default Do i need a tune?

Every since i put longtubes on my car it has been having trouble starting. Sometimes it will start right up but other times it takes a few tries to get it to start. The car is also down on power after the header install. I raced my dads stock a4 Camaro and lost by about two cars so i know its not where it should be power wise. Is a tune what i need to get my car running right again?
Reply
Old Jun 2, 2011 | 03:06 PM
  #2  
RamAir95TA's Avatar
TECH Senior Member
iTrader: (2)
 
Joined: May 2005
Posts: 9,467
Likes: 8
From: South Jersey
Default

I would immediately suspect burned plug wires due to the headers. Headers alone will not make your car slower. A tune will help, but will not fix an already poor running car.

Are they ceramic coated? Some ceramic coatings can foul out O2s when it burns up for the first time.
Reply
Old Jun 2, 2011 | 03:12 PM
  #3  
will1380's Avatar
Thread Starter
Staging Lane
 
Joined: Feb 2009
Posts: 99
Likes: 0
From: Kansas City MO
Default

They are ceramic coated. I've replaced the wires and 02's already and still no luck. I paid alot of attention in wrapping the headers with header wrap to make sure they weren't going to burn any wires.
Reply
Old Jun 2, 2011 | 04:22 PM
  #4  
gregrob's Avatar
TECH Senior Member
iTrader: (8)
 
Joined: Sep 2008
Posts: 5,130
Likes: 4
From: 6,000+ feet
Default

You probably got a plug wire crossed up. Double triple quadruple check that the wires match the firing order...
Reply
Old Jun 2, 2011 | 05:07 PM
  #5  
will1380's Avatar
Thread Starter
Staging Lane
 
Joined: Feb 2009
Posts: 99
Likes: 0
From: Kansas City MO
Default

I just spent an hour double,triple,quadruple checking all the wires and they all matched up to the firing order. Also checked again while i was under the hood and mad sure no wires were burnt.
Reply
Old Jun 2, 2011 | 07:58 PM
  #6  
5_LTR_ETR's Avatar
Launching!
 
Joined: Oct 2009
Posts: 247
Likes: 0
Default

recheck if all your plugs got completly tightened on reinstallation. i managed to miss 2 of mine
Reply
Old Jun 2, 2011 | 09:06 PM
  #7  
02v8ta's Avatar
TECH Resident
iTrader: (8)
 
Joined: Jun 2008
Posts: 958
Likes: 0
From: south jersey
Default

Originally Posted by RamAir95TA
Are they ceramic coated? Some ceramic coatings can foul out O2s when it burns up for the first time.
Not to hijack but really? Getting some installed soon is why i'm asking. Sooo after the first few cycles it'll either foul the 02s or not, is it common?
Reply
Old Jun 3, 2011 | 08:00 AM
  #8  
moehorsepower's Avatar
TECH Addict
iTrader: (3)
 
Joined: Feb 2003
Posts: 2,334
Likes: 17
From: Texas
Default

All cars no matter the same, react different, A local muffler shop had a stock LT1 and installed headders and ran slower until I had to do a tune, When we had the shop I would see headder installs cause lean A/F and some to go to the Rich side and some run better without any tuning, so if all checks out ok, You probably need a tune, Maybe have some one scan it first before you invest to see what its doing.
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Jun 3, 2011 | 10:26 AM
  #9  
will1380's Avatar
Thread Starter
Staging Lane
 
Joined: Feb 2009
Posts: 99
Likes: 0
From: Kansas City MO
Default

Could bad injectors be causing the problems I'm having? Car has 142k on it and still has the factory injectors on it.
Reply
Old Jun 3, 2011 | 10:51 AM
  #10  
moehorsepower's Avatar
TECH Addict
iTrader: (3)
 
Joined: Feb 2003
Posts: 2,334
Likes: 17
From: Texas
Default

Originally Posted by will1380
Could bad injectors be causing the problems I'm having? Car has 142k on it and still has the factory injectors on it.
Well if the car was running fine before then unlikely its the injectors..
Reply
Old Jun 3, 2011 | 03:43 PM
  #11  
nighthawk15's Avatar
TECH Resident
 
Joined: Jul 2007
Posts: 749
Likes: 1
From: Spokane, WA
Default

Did you use cut to fit wires? If you did, did you make absolutely sure all of your connections were good? Also, sometimes the stock module if not tuned or replaced with an LT4 module can pick up false knock from headers or a loud exhaust and screw with the timing, but that still shouldn't give you problems starting the car.

Last edited by nighthawk15; Jun 3, 2011 at 03:50 PM.
Reply
Old Jun 3, 2011 | 08:06 PM
  #12  
will1380's Avatar
Thread Starter
Staging Lane
 
Joined: Feb 2009
Posts: 99
Likes: 0
From: Kansas City MO
Default

I have another question. I'm going to go ahead and replace the injectors since they have 142k miles on them. I was wondering if this set of injectors is what i need and will fit my lt1 engine.

http://cgi.ebay.com/ebaymotors/24-LB...Q5fAccessories

Last edited by will1380; Jun 3, 2011 at 08:23 PM.
Reply
Old Jun 3, 2011 | 09:16 PM
  #13  
RedHotG8's Avatar
TECH Fanatic
iTrader: (1)
 
Joined: May 2010
Posts: 1,419
Likes: 1
From: Chicagoland
Default

To get the most power out of the headers you need a tune, which will definitely make your car run better.
Reply
Old Jun 3, 2011 | 09:57 PM
  #14  
transbird95's Avatar
TECH Enthusiast
15 Year Member
Liked
iTrader: (4)
 
Joined: May 2010
Posts: 736
Likes: 12
From: little falls minnesota
Default

Originally Posted by will1380
I have another question. I'm going to go ahead and replace the injectors since they have 142k miles on them. I was wondering if this set of injectors is what i need and will fit my lt1 engine.

http://cgi.ebay.com/ebaymotors/24-LB...Q5fAccessories
I wouldn't worry about the injectors man. If it was working fine before I doubt it's the injectors and 145k isn't all that bad. I would scan it first and see if it's picking up knock and see if there is any codes first. If you can't find anything that you think you could have done wrong check the fuel pressure.
Reply
Old Jun 5, 2011 | 09:10 AM
  #15  
MavsFORMULA's Avatar
Staging Lane
iTrader: (4)
 
Joined: Sep 2009
Posts: 77
Likes: 0
Default

I replaced mine on my last LT with 150k due to a fueling problem, which i should've known in the first place was the fuel pump. The injectors were perfect and are now in my buddies heads and cam mustang. The car shouldn't need a tune but it also will help. Check your fuel pressure.. Any engine codes?
Reply
Old Jun 5, 2011 | 10:04 AM
  #16  
BigD383lt1's Avatar
On The Tree
 
Joined: Sep 2010
Posts: 198
Likes: 0
From: Dunedin, Florida
Default

Did you have to extend the harness for your o2 sensors if so did you do it equally? If you change the injectors unless going with the stock size you will defiantly need a tune and if your going to change injectors you should go up in size if you plan on doing any mods in the future. I don't think it is needed at this time I've seen guy's run for 200k with stock injectors. I would look elsewhere the odds of it being injectors are slim.
Reply
Old Jun 5, 2011 | 10:53 AM
  #17  
ZFreie's Avatar
TECH Enthusiast
 
Joined: Aug 2010
Posts: 543
Likes: 0
From: New Hampshire
Default

Originally Posted by BigD383lt1
Did you have to extend the harness for your o2 sensors if so did you do it equally? If you change the injectors unless going with the stock size you will defiantly need a tune and if your going to change injectors you should go up in size if you plan on doing any mods in the future. I don't think it is needed at this time I've seen guy's run for 200k with stock injectors. I would look elsewhere the odds of it being injectors are slim.
160k on my stock injectors. Still runs great!
Reply
Old Jun 30, 2011 | 01:05 PM
  #18  
FormulaJoe's Avatar
TECH Regular
iTrader: (5)
 
Joined: Dec 2010
Posts: 497
Likes: 0
From: Too close to the cities, MN
Default

Originally Posted by BigD383lt1
Did you have to extend the harness for your o2 sensors if so did you do it equally?.
Do you need to have them both the same extension?
Reply




All times are GMT -5. The time now is 02:35 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE