My first ls

Reply Subscribe

Thread Tools

Search this Thread

Jan 25, 2018 | 09:38 PM

Squarebody1

Thread Starter

Teching In

Joined: Jan 2018

Posts: 6

Likes: 0

My first ls

I'm new to the group. I'm hoping for a little advice I have a 2000+ 5.3 truck engine and 4l60 transmission I'm putting in an 85 Chevrolet pickup. I had the engine running before I pulled it from the donor. I installed a btr stage 4 truck cam, valve springs, timing set, oil pump, and long tube headers. I'm running a flashed computer. I put a 3200 stall in trans. Dropping it all in this weekend. I have a set of 36# injectors but I'm not sure I'm going to need them. Anyone farmilliar with this setup? Am I going to need a tune immediately or will it run on stock tune? It will be open headers on initial start so I'm not planning to run it long. Thanks in advance

Jan 26, 2018 | 06:43 AM

Floader

TECH Apprentice

iTrader: (32)

Joined: May 2004

Posts: 338

Likes: 0

From: Vermont

It will run on the stock tune if you dont change the injectors. It probably wont run real well, but it should fire up and idle as long as the VATS is deleted.

Jan 26, 2018 | 07:17 AM

Squarebody1

Thread Starter

Teching In

Joined: Jan 2018

Posts: 6

Likes: 0

Thank you floader. The vats is deleted. I pulled the setup out of another older truck and it ran in it. I'm not all up on the computer thing , that's why I'm here. Why will it run rough? Is it because of the cam and different air flow? If I buy a handheld tuner , can I tune it myself?

Jan 26, 2018 | 09:14 AM

LS1MCSS

TECH Junkie

iTrader: (18)

Joined: Jan 2006

Posts: 3,831

Likes: 8

From: Dover, Arkansas

Quote:

Originally Posted by Squarebody1

Take it to a good tuner. Hand held tuners are usually a joke.

Jan 28, 2018 | 09:20 AM

Squarebody1

Thread Starter

Teching In

Joined: Jan 2018

Posts: 6

Likes: 0

So I've got the motor and trans in. I'm finishing up the wiring this morning and plan to start it in a few hours.

The donor truck had no 02 sensors. Exhaust was unhooked at manifolds. With a flashed computer I would still need them, correct? And again, why will it run rough with just a cam swap. I'm used to older sbc stuff. Thanks again

Jan 28, 2018 | 09:20 PM

Squarebody1

Thread Starter

Teching In

Joined: Jan 2018

Posts: 6

Likes: 0

Chirp chirp

Jan 28, 2018 | 09:57 PM

G Atsma

TECH Senior Member

Joined: Jun 2016

Posts: 22,301

Likes: 3,625

From: Central Cal.

Because a cam changes the way the engine pulls air in, which would change fueling and spark advance parameters. A different cam needs a different tune. A stock tune will not like a bigger cam, making for rough running.

10 Reasons Daily Driving a Swap Project SUCKS! (& 1 Reason to Do It Anyway)

Michael S. Palmer

6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Brett Foote

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Pouria Savadkouei

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Verdad Gallardo

7 Most Reliable High-Performance Engines GM Has Ever Built

Verdad Gallardo

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

Verdad Gallardo

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

Pouria Savadkouei

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

Verdad Gallardo

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Pouria Savadkouei

Top 10 Most Powerful Chevy Trucks Ever Made!

Jan 28, 2018 | 10:10 PM

G Atsma

TECH Senior Member

Joined: Jun 2016

Posts: 22,301

Likes: 3,625

From: Central Cal.

You can't delete the forward O2 sensors, as they are vital to running the engine.

Jan 28, 2018 | 10:23 PM

#10

Squarebody1

Thread Starter

Teching In

Joined: Jan 2018

Posts: 6

Likes: 0

It's running. No codes and no 02 sensors. Was told I didn't need them but will get some if I do

Jan 28, 2018 | 11:33 PM

#11

G Atsma

TECH Senior Member

Joined: Jun 2016

Posts: 22,301

Likes: 3,625

From: Central Cal.

It's running in open loop, speed density. About as accurate as a carburetor.

Jan 30, 2018 | 12:58 PM

#12

Lsxford

TECH Enthusiast

iTrader: (7)

Joined: Nov 2016

Posts: 666

Likes: 74

From: Winfield AL

Quote:

Originally Posted by Squarebody1

It's running. No codes and no 02 sensors. Was told I didn't need them but will get some if I do

You need to find a tuner and consult them on whether to use o2s or not. If its tuned properly it will run great in open loop, alot of turbo cars are this way. Are you running a MAF sensor?

G Atsma Will it not use the MAF sensor for fueling even without O2s? Should be open loop MAF or is that a custom OS only?

Jan 30, 2018 | 03:31 PM

#13

G Atsma

TECH Senior Member

Joined: Jun 2016

Posts: 22,301

Likes: 3,625

From: Central Cal.

The MAF tells it how much air is coming in. The O2's tell it how much of that air got used. Which of those two functions would you rather do without?

Jan 30, 2018 | 06:06 PM

#14

Lsxford

TECH Enthusiast

iTrader: (7)

Joined: Nov 2016

Posts: 666

Likes: 74

From: Winfield AL

Quote:

Originally Posted by G Atsma

The MAF tells it how much air is coming in. The O2's tell it how much of that air got used. Which of those two functions would you rather do without?

i understand what each sensor does. IMO for a daily i would want all 3, but for a performance type vehicle like a weekend toy you can get by with none of the 3 and it will perform fine. there are pros and cons to all of them, CLMAF, CLSD, OLMAF, OLSD. i believe it comes down to 2 things, the person that will be driving the vehicle and the person that will be tuning the vehicle. OLSD may not be as accurate as CLMAF, but it can run efficiently with great drivability.

my own vehicle runs OLSD btw

different strokes for different folks.