How do these cats affect the noise level of a 355? With a standard oem exhaust system fitted will the hyper flows increase the noise level at idle compared with oem cats?
stronger /louder exhaust note due to the nature of high flow cats....but not obnoxious like cat test pipes.
Hyperflows with Tubi gave me the worst droning ....could not bear it on motorways. Now have hyperflows and Larini.....zero droning, elevated increase in idle noise compared with oem cats...wonderful scream with throttle applied. Don't like ceramic cats so oem are out for me
interesting ...I have tried the following set ups: 1) stock exhaust with cat delete pipes and challenge bypass pipe- loud & droning (take a aspirin). 2) stock exhaust with hyperflow and bypass valve- little louder & no droning(great for touring....nice F1 sound when accelerating ). 3) race tubi with cat delete pipes and challenge bypass pipe - obnoxiously loud and droning (take even more aspirin). 4) race tubi with hyperflow and bypass valve- little louder than stock and no droning (quiet when cruising on highway so great for long distance touring...great F1 sound when bypass opens upon acceleration.
I have the tubi/hyperflow setup and do not have any droning issues on the highway. However I have a spider- maybe droning is more noticeable on coupes? I love the set up by the way...both tubi and hyperflow are quality products.
I have hyper-flows with a tubi. Drone doesn't bother me. Hyper-flows with a stock muffler would seem pretty tame I think. I am considering dumping the hyper-flows for test pipes with O2 extenders.
CFF355, what do you mean by 'race tubi' - is that the old style tubi muffler where the output pipes split into two at the very end? Also, I run an old style tubi with hyperflows - sounds very nice, but a bit loud. Compared with stock cats, the sound is much more aggressive and also much louder. I run a capristo bypass valve too. I was thinking of going back to stock muffler with hyperflows. If anyone has this combo, please let me what it sounds like.
Tubi originally made different levels (3 levels according to the F dealer) of muffler sound....the standard tubi's sound levels are almost identical to the oem muffler. The race tubi does have the twin outlet....but I don't recall if the other tubi's had that style of outlet or not. My car originally had the standard tubi and the Ferrari dealer upgraded my muffler to the race tubi when customers complained about the standard tubi's sound levels. Periodically I switch exhaust combos (tubi,stock muffler, bypass or challenge bypass pipe)...with stock muffler and hyperflows the sound is just a little more quiet....but not by a lot. If you have an oem muffler you might just want to install it and see if this is the sound level your looking for.
I found the hyperflow and twin valve capristo is the best except for the droning at idle when cold. This happens until the bypass closes once the car is warmed up. Also have the tubi headers but they did not seem to make a noise diff over stock.