The Right Engine for my Nissan 240z?
So, you have finally decided to breathe new life into your venerable old Nissan 240Z by doing an engine swap, but now the question is “Which engine is best?” There are several possible choices, such as the RB26DETT, the 2JZ in most of its variants, the SR20, or even the mighty V8 LS1, but the choice is made a lot more difficult by the fact that the engine bay of your 240Z will accept almost any engine. While the SR20 is a viable choice, the LS1 and 2JZ are very heavy, and require major structural modifications/reinforcing to work, although there are several known instances of these engines running in 240Z’s successfully.
Nevertheless, swapping an engine involves a whole lot more than making it fit without having to cut into the bodywork. For instance, bear in mind that the 240Z was made in a different time. Although it answered the needs of its time by providing adequate, though not brilliant handling, and by some standards, performance that was slightly above average, although this had more to do with its low overall weight than brilliant engine design, and the only real competition it had was from some Italian and German sports cars.
All of the engines mentioned above are more powerful, fuel efficient and reliable than the 240Z’s original engine by several orders of magnitude. This of course raises the issue of which engine is more cost effective; particularly given the fact that transplanting a heavy, high performance engine into a 240Z will only result in a light weight pocket-rocket with inadequate handling, steering, and braking characteristics, unless other, major and critically important modifications are carried out in conjunction with the engine transplant.
The fact is that the 240Z’s body shell was never designed to be able to cope with the vast amounts of horsepower and torque that any of the above engines are capable of developing. In fact, one of the first issues that must be addressed when contemplating an engine swap is the amount of body reinforcing that is required to prevent undue twisting and deformation of the frame under severe acceleration and cornering conditions.
Some Points to Ponder.
As stated before, the purpose of the engine swap should be clear even before the old engine is removed from the car. The first question should be, “What is that I want to do with the converted 240Z? Some of the possible answers are:
Nonetheless, converted 240Z’s abound, and engines such as the mighty LS1 from General Motors, the hugely adaptable, and modifiable 2JZ from Toyota, and even the SR20 series from Nissan have all been successfully installed, but the firm favorite among power junkies for fitment into a 240Z is the spectacularly successful RB26DETT inline six cylinder engine from Nissan. However, that is only half of the story.
The Other Half of the Story.
There is no doubt that there are easier engines to fit into your 240Z than an RB26DETT, but it is also true that this is the engine that is most often used in engine transplants into 240Z’s. Some of the reasons are that-
However, the added power means higher speeds, which in turns means the brakes have to be upgraded quite substantially to be able to stop effectively. Moreover, the sedate speeds of which the original 240Z was capable did not place the kinds of demands on the suspensions that a RB26DETT engine will, therefore, it is necessary to upgrade the suspension to a level where it can keep pace with the increased cornering forces.
Failing to address these issues will only result in a super fast 240Z with uncontrollable amounts wheel spin under hard take-offs, that cannot be controlled around corners, and that cannot be stopped effectively, and who needs that? Of course, the degree to which these issues will affect the drivability of the final product depends entirely on the way it is driven, but who wants to spend in excess of $ 100 000 to build a car that cannot be driven around a track safely?
The other side of the coin is of course your available budget, but the nature of this beast is such that it does not permit half measures. It is all or nothing, and unless you want to end up with a half-baked conversion that never performs satisfactorily, or safely, there is no other alternative than to go the full hog. Anything less is a waste of time and money, and you would be better off buying a complete, later model competitive car, which is certainly the more cost effective way to get, and remain competitive in most racing disciplines.
Nonetheless, if you have your heart and mind set on fitting a RB26DETT engine into your 240Z, take a moment to consider the following parts list. If you want to build a fast, reliable, and above all well-handling car that can handle anything from street racing to running with the big boys on the track, this list represents what is regarded as the minimum requirements.
Suggested Parts List.
Alternatively, a fully rebuilt R34 Skyline RB26DETT engine in which case, the following parts and modifications are recommended:
Nor will you need most of this, although even a standard RB26DETT engine can benefit from some of the items on the following list:
However, regardless of whether you use a standard or modified RB26DETT engine, you cannot do without the following changes to your drive train:
Then there is the issue of possible under steering under acceleration or hard cornering at high speeds, which can occur whether you are running a standard, or modified RB26DETT engine- or for that matter, any other high performance engine. Therefore, you need at least the following parts to be able to set up the suspension properly:
Then of course, you need to able to stop, and for this, you will need the following as bare minimums:
Is It Worth It?
This is entirely a matter of opinion, but the above parts list is from an actual conversion of a 240Z to run an RB26DETT engine. This particular car was converted in South Africa three years ago and is currently used for track racing, where it is competitive against new factory-built BMW’s, Audi’s, Fords, and Renaults, among others. Of course, you may not want to go up against factory-built racers, but there is nothing much you can do with a half-baked conversion, and with 240Z’s, it is all or nothing.
Nevertheless, do you want to know what it cost to build this particular 240Z- bearing in mind that all you want is a safe, reliable street racer, or occasional drifter? This particular erstwhile 240Z does all of that, but it also very good on the track, which is like killing all possible flies with one swat.
Nonetheless, it cost I.3 million South African Rand, which when translated into $US, comes to $106 000 at the time of writing in April 2015. Is it worth spending that much money on a conversion when $100 000 can almost buy you a Lamborghini or Ferrari? It might be worth it for some, but in the opinion of most car enthusiasts who have to work for a living, it is most certainly not. You decide.