I’ve been following this thread with interest, more so on eventually validating the potential gains.
I was involved heavily in remapping another NA engine around 16/17 years ago. This was the TVR Cerbera AJP 4.5 V8. On paper it should have produced 420bhp, but when we tested a number of these the output varied from 325-360bhp. With a relatively lightweight 1250kg the car was still stupidly fast so not many owners really questioned the power.
However, my actual car at the time put out 339bhp and 339lb/ft. After an incredible amount of R&D or trial and error, plus dyno time, we achieved 420bhp. To do this we did the following:
Removed the original MBE ECU and replaced with a standalone Emerald ECU to allow easier mapping. This alone took us to 385bhp / 353lb/ft. The same later proved achievable on the standard ECU.
Inverted the air box to create a greater
Volumetric area and redesigned the OEM foam filter, creating a filter that was “egg box” in appearance compared to a flat surface (to create more contact surface area) and with the correct PPI rating. I had a good contact at the time who was able to manufacture them for me. 390/357
Next was the game changer and hardest from an R&D perspective, work was already underway prior to me being involved but the timing was right. This was to change the existing 8 Long over lapping purple induction hoses and replace them with shorter none overlapping hoses. As the hoses were offset and of a set diameter at both ends, then designing the correct hoses was a challenge, however I had some brilliant at the time software support (mainly for fluid flow, but applicable for gas flow), so was able to design the hose to perfection and then have them put into production. Once done and with further mapping we saw 406bhp/355lb/ft
Next was to introduce linked decat pipes (similar to a H pipe), with mapping this took us to 410/365
Final change was to a larger bore exhaust and we also removed and refaced / tidied the manifolds. With mapping the magic 420bhp was achieved!!!
It took hours upon hours of R&D and testing for each stage. The original MBE map for these cars was poor and the power delivery famous for its “camel hump” delivery (easily seen on the power graphs). This erratic delivery was removed once the short induction was fitted. As all the engines were handbuilt to differing levels of quality, but all pretty much had the same original map, then it’s easy to see why the power outputs varied massively, despite being well below quoted.
Sorry for the ramble.
Back on topic then my point is that I am sure that there could well be a very decent gain to be had on the Maserati 4.7 (and 4.2). Most common quote is that NA will only gain 10% max and in many cases this is correct. But it’s not until you understand the original software that you can calculate if the existing map is optimal or in some cases sub optimal which allows for power gains.
Will continue to follow with interest and whether the gains are 40bhp or 90bhp it will be well worth it…..
