J-Body Automobiles Forum banner
1 - 1 of 1 Posts

·
Administrator
Joined
·
106 Posts
3400 Engine Swap

Chapter 1: Introduction / Why should I swap?

Motor vehicle Automotive lighting Vehicle Automotive tire Automotive design

In this chapter we will help you to understand what exactly you're getting yourself in to. After reading this you should be able to make an educated decision
as to whether this swap is right for you and have a good idea of the benefits & pitfalls of performing this engine swap

What is the 3400 & why it is better than your current motor?

Then 3400 is one of GM's 3rd generation 60°V6 motors. The engines used in our 2nd generation J-Bodies is the gen 2 version of the 60° V6. The Gen 3 motors
show significant improvement over the gen 2 variations in power & fuel efficiency. The 3100 is also a gen 3 motor and depending on year, is nearly identical to the 3400,
save for the bore.

GM rates the 3400 V6 at around 185 crank horsepower depending on application. All the motors are the same between applications (2005 Equinox being the exception, you
can't use that motor, more on that later). The only reason they are rated at different horsepowers between models is because of the differences in intake exhaust & tuning on that particular model.
There are several dyno results that prove a stock 3400 in a J-body will make 180-190 HP at the WHEELS. So GM has either under rated or under tuned these motors in
their vehicles.

So this means you are looking at approximately 210 HP at the flywheel. Quite an improvement over the 140 HP your tired 3.1 is rated at,
or the 130 of your 2.8. You will shave at least 1 full second off your quarter mile time, with basically stock 3400 swapped cavaliers running as fast as 14.5 seconds at 93mph through the 1320! If that isn't enough reason to do this swap, I don't know what is!

Where to get your 3400 Engine

The junkyard! www.car-part.com is your friend for locating your new motor. But first you need to know what to search
for.
The 3400 V6 Can be found in the following GM models.

  • Buick Rendezvous
  • Chevy Monte Carlo
  • Chevy Lumina APV
  • Chevy Venture
  • Olds Alero
  • Olds Silhouette
  • Pontiac Aztec
  • Pontiac Grand Am
  • Pontiac Trans Sport

The 3400 became available as early as 1996 in the trucks, 1999 in the cars. It is generally advisable to get an engine from a 2000+ model year if possible due to some beneficial design changes.
Engines before 2003 were very susceptible to a leaking Lower Intake Manifold. If you get one of these motors no matter what the mileage, plan to replace the LIM before installing
the engine to save yourself the headache & possibility of ruining the engine.

What to look for in a 3400 & what you will spend

Expect to pay anywhere from $300 - $800 for a 3400 depending on your area & the mileage of the motor. I picked up my 2001 engine with 6k on it for $600.
Many junkyards will deliver the engine to your door.

I would look for 2000+ model year engine with less than 50,000 miles on it. Make sure the junkyard has some sort of warrantee in case the engine is blown.

If you are swapping into a 92-94 J-body, it is even better if you get the motor from a Grand Am, as those engine have the proper fuel line routing that will
plug right in to your quick connect fittings. <91 J-Bodies don't have the quick connects, so it doesn't matter. You don't HAVE to use the Grand Am fuel lines to
make it work, it just makes it that much cleaner & easier.

How hard is this swap & how long will it take me?

If you have decent mechanical skills, this swap is pretty straight forward. I would not recommend it for a complete novice unless you have somebody more experienced
to help out. You'll need a full set of basic mechanics tools, engine hoist, jacks & jack stands. If you have ever pulled an engine before, this swap will be
no problem for you, as it is basically just an R&R with a few extra modifications.

This swap can go as quick or be as drawn out as your want. I would plan on having the car down for at least 2 weeks, but could easily take up to a month
to get all the little bugs worked out. If you have a lot of time to devote to the project, you could probably get it all hammered out in less than a week, but don't
try to rush things & make mistakes. If you have your 3400 all prepped & ready to go and are really determined, you could probably complete the swap in a weekend, but still
plan on extra time for working out little bugs.

The basic changes required to make this engine work in the J-body

There are a few somewhat major modifications that must take place & many small ones. Here are the major items & considerations.

  • Custom front motor mount bracket must be made or purchased. J-body performance sells this mount, or if you have fabrication skills, you can easily make your own.
  • A custom downpipe will need to be made. Pretty much any muffler shop can do this for you.
  • The computer. You can run this motor on the stock tuning by swapping in your old injectors. It will run, but not optimally. The best option is to use the
    2000+ 3400 multec 2 injectors and purchase a custom tuned chip. Burn is currently selling chips for this setup.
  • All other changes are minor, such as moving the wiring for a few sensors, a few different lines & hoses, etc. All this is listed in the parts list chapter
Things you DON'T need to change

  • Your stock V6 transmission will bolt up to the 3400 with no modifications. Just use the clutch (performance clutch recommended) and flywheel from the old motor.
    If you have an automatic, you will need to use a Quad 4 throttle box in order for the kickdown cable to function
  • A complete computer & wiring swap is not necessary. All the 3400 engines run OBD2 from the factory. But in our swap, we will re-use the our wiring harness and
    computer with some slight modifications.
Why you should choose the 3400 over other possible engine swaps

The 3400 swap has proven itself time & time again as a simple swap with noticeable gains in power & efficiency. the 3800 SC swap is another swap that many
people consider. That engine is a 90° engine that is a MUCH tighter fit into the J-body engine bay. Many more modifications & headaches are needed to make that
swap work, for not much more power over the 3400.

The 3400 is definitely the best bang-for-your-buck engine swap available at this point in time.

Chapter 2: What parts am I going to need & what will this cost me? »
Page Last Modified: 06/19/2018 4:15 pm

3400 Swap Navigation

  1. Introduction / Why should I swap?
  2. What parts am I going to need & what will this cost me?
  3. Removing the old engine
  4. Prepping the new motor - Part 1
  5. Prepping the new motor - Part 2
  6. Installing the new motor (Coming Soon)
  7. Tuning your new motor (Coming Soon)
  8. Troubleshooting your swap (Coming Soon)
  9. Frequently Asked Questions (Coming Soon)
3400 Swap Home
 
1 - 1 of 1 Posts
Top