Top Ten Things Commonly Forgotten or Underestimated When Doing Modern Engine Swap

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vette-prepped-for-engine-sw.jpgModern Muscle Compiles A Helpful List Of The Most Common Problems Overlooked

The experts at Modern Muscle have compiled a helpful list of the top 10 things people commonly forget or underestimate when doing a late model engine swap.  ?Over the years we have seen the same problems over and over in our shop and heard about them around the country when it comes to people doing engine swaps,? says Justin Meyers, Vice President of Modern Muscle. ?That’s why we thought it was important to get this list out there to help all of those builders in the future avoid common pitfalls of taking on a modern engine swap.?

1: Wiring

Wiring is always a constant problem for people no matter what size project they are taking on, but especially in modern engine swaps.  ?This is probably the biggest single issue we see.  Wiring can be very complex and it requires a lot of understanding about amperage, wire gauge, relays, and overall circuits,? Meyers says. ?A perfect example is the electric fan circuit.  A lot of people run two wires (power and ground), but the circuit needs to be tied into the cooling system, air conditioning system and the system needs one or two relays.?

2: Cooling Systems

Cooling systems aren’t tricky, but many people just underestimate the volume of work that goes into it. ?Mechanical fans will work okay with older engines, but today’s engines run hotter and require a lot more cooling.  Most people just don’t think about specific functionality of the modern engine they are installing and reinstall the mechanical fan or they hook up a cheap electric fan that doesn’t have enough flow,? says Meyers.

3: Headers

Most people know or have a good idea that the exhaust manifolds are going to need to be modified.  It isn’t until the engine is sitting in the engine compartment that they realize how complex the issue can be and people can quickly get in over their heads. ?Steering linkage, spark plugs and wires can really cause some headache when fabricating a header.  By the time most people have a good mental image of how the headers need to lay out, they come to the realization that the tubing is going to hit the frame or body, and have to start from scratch again, a common and costly mistake.? says Meyers.

4: Oil Pans and Pick Up Tubes

Since most chassis and cross members are in different locations, oil pan clearances are often a problem.  Luckily with the wide variety of aftermarket oil pans out there, people usually don’t have to build custom pans and pick up tubes. It takes a little more effort to find exactly the right fit.

corvette-engine.jpg5: Steering

Steering linkage can get tricky when trying to figure out how to navigate past the headers and around everything.  In addition to that, many people upgrade their suspension and steering systems at the same time as the engine.  With the wide variety of aftermarket components available, sometimes the combination of parts used can require an odd combination of steering linkage.

6: Air Conditioning

Late model engines usually have mounting brackets or bosses for air conditioning compressors.  While this can make it convenient, the compressors are usually mounted on the lower sections of the engine.  This can create problems when trying to get an engine between the frame rails.  So, mounting the compressor in a different location is often necessary.  In addition to the compressor, a lot of people have problems laying out the system. Trying to figure out where the accumulator/dryer or fixed orifices go.

7: Fluid Reservoirs

One commonly overlooked modification is that in general all of the reservoirs need to be changed.  The cooling system isn’t a big deal but the power steering reservoir can be tricky for people.  Packaging gets really tight and sometimes a remote mount reservoir is needed.

8: Drive Shafts

While drive shafts don’t seem like a big deal, people will sometimes run into problems either measuring the drive shaft or selecting the right yoke or flange.  ?Once and a while, we run into a problem where people don’t tell the drive shaft shop that they put a blower on the car and it has 800 horsepower,? continues Meyers.  ?So, they will bend the driveshaft or kick it out the side of the car when they hammer it.?

9: Fuel Systems

Most people know they need larger and higher quality fuel lines and better filtration.  Where they run into problems is selecting the right fuel pump.  ?We usually recommend people try and use a factory style in tank pump for their daily driver,? says Meyers.  ?Frame mounted high volume pumps vibrate, run hot and usually aren’t designed for extended driving cycles.  So, failure and cabin noise can be a problem.?

10: Torque Converters

If the rest of the driveline is staying the same (designed for an early model engine) sometimes getting a converter with the right flywheel pattern and transmission spline count can be tricky.  There are aftermarket ?hybrid? converters to solve this problem.  
Final Thoughts

A lot of the issues mentioned above can be solved ahead of time with extensive research and forethought for system layouts. Today, there is a wealth of information available online (in forums!), through magazines and at car shows.  Odds are, you won’t be the first person to do that particular swap.  Finally, don’t be afraid to go to an expert for help when it’s needed. It will save you a lot of time, money and headaches in the long run.
About Modern Muscle

Located about 1 hour outside of Chicago, in Oswego, IL. Modern Muscle has the experience and dedicated personnel to help all of your vehicle build dreams come true. Providing a variety of services from complete restorations to high performance engine building to performance computer tuning and more, Modern Muscle has quickly become Chicagoland’s premier hot rod shop. In their 10,000 square foot facility, they have everything from a dyno jet to a full machine shop. No job is too small or too large.  For more information or to get your next project started, log on to or give them a call at 630-898-5933.
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