I don't see how the number of cylinders would make a difference. Maybe your results are because of something else like GDI?*Using TCW3 in 4 cylinder engines at 640:1 was a bit too much for smaller engines, so I cut the ratio back 980:1 which was better ... Smoother , quieter idle , instant start up in any weather - little to no gain in gas mileage (too much at 640:1 it actually reduced gas mileage in 4 cylinder engines - 6 & 8 cylinder engines handles a 640:1 ratio much better) .