Triple Mikuni Carburetors
Well when it comes to the induction system on the early 240z and 260z zcar you have a few choices to improve the performance of your engine. Some of these choices include factory parts such as the 280z and 280zx fuel injection systems.
However most underestimate the simplicity and performance potential from the early Twin SU carburetors made by Hitachi and came standard on the 240z. Originally on my stroker engine I was going to use the twin SU’s fit them with richer needles and seats and give them a throttle bore. It would have been cheaper and it would have looked standard, but after some consideration I thought the only proper way to do it was to go with Triple carbs.
Like anything in life there is always going to be a debate over what is better. In the case of Triple carbs it is no different. You can fit anything you like really I’ve seen Triple SU’s, Triple Webers and Triple Mikuni’s and I’m sure there are many other combinations. The Triple Mikuni’s and Triple Webers were used in competition back in the 70’s and I believe both were available as factory performance parts. Triple Solex carbs are the earlier style of Mikuni, I believe Mikuni bought out the licence from Solex and continued to make them. To some the early Solex version is worth a bit of coin. For me this was less important.
In Japan there are also Triple SK carbs, I do not know much about these although from what I have seen they are very sexy and very well constructed carbs. When I bought my Schneider cam kit the guy selling the cam kit also had a set of these. They were very tempting to buy, if I hadn’t already bought my 44’s I probably would have bought them.
I personally wanted to go with Triple Mikuni’s because most owners raved about how great they were and I really loved the straight 6 Triple carb combo. You can get them in all sorts of sizes the triple 40’s were most common and are probably ideal for the L24. I would have liked to get my hands on some Triple 50’s which are very rare and ultra expensive, however I believe you can bore out the 44’s (what I got) to about the same size.
The next thing to consider is your intake manifold. There are so many out there but what I have noticed is that some are long and some are short. Having read through some books on the topic of runner length I understood this was important. I asked the question on the classic zcar website. You can view the topic if your interested. The general consensus regarding my short mikuni manifold was not to really worry too much about it. I figure I can always worry about this when it comes time to decide on the velocity stack length. Which is something I wanted to discuss here, because alot of people tend to ignore this factor. It is one of the reasons I have not bought a set for mine yet(mine didn’t come with any just K+N filters). Even the previous owner of my carbs didn’t take this into account and had slipped on K+N filters.
I have found a guy on ebay who will cut them to any length dependant on your needs. This is the ideal way to go if you ask me.
If your looking for the ultimate in carburetor performance from your L-series engine, triple sidedrafts are the way to go. I will post more information up after I have fitted these to my engine for now they are waiting patiently :). I don’t want to cover jet/venturi/chokes selection etc. here because I have not been through this process yet, however it is important to keep in mind that most people who have had hassles with Triple carbs are those that have ignored these factors in tuning their engines.
