Have Cobb catted on for 4+ years. I finally bought some used Macht Schnell catless a couple months ago just to check if catless claims I figured were mostly bunk all these years, actually were.
Catless with flapper closed are no louder than high flow catted with flapper open for cold start. No sound difference on cruise/normal driving. Catless under boost may be a little louder, but raspy sounding to me.
As you'd guess, no change in spool, boost, etc. It's pretty much dictated by boost control, tuning and turbines. Literally maybe a +2whp difference across the board on VD with hybrids at 20psi.
People buy catless because they're cheap and want to believe they're significantly higher performing than high flow catted. Not on these cars. If you already spent the money high flow catted, I wouldn't bother with catless. I put the Cobb's back on if it's any indication. If you're interested in the Macht Schnells anyway, LMK, they're sitting in storage wait to be sold as soon as I have time lol
Have Cobb catted on for 4+ years. I finally bought some used Macht Schnell catless a couple months ago just to check if catless claims I figured were mostly bunk all these years, actually were.
Catless with flapper closed are no louder than high flow catted with flapper open for cold start. No sound difference on cruise/normal driving. Catless under boost may be a little louder, but raspy sounding to me.
As you'd guess, no change in spool, boost, etc. It's pretty much dictated by boost control, tuning and turbines. Literally maybe a +2whp difference across the board on VD with hybrids at 20psi.
People buy catless because they're cheap and want to believe they're significantly higher performing than high flow catted. Not on these cars. If you already spent the money high flow catted, I wouldn't bother with catless. I put the Cobb's back on if it's any indication. If you're interested in the Macht Schnells anyway, LMK, they're sitting in storage wait to be sold as soon as I have time lol
Before and after virtual dyno. Log 3-5x a day in the same spot for years, I'm pretty consistent at it.So you dyno'd the car before after same day? Do you have any logs? There's a lot more to it than just WHP. Especially if you didn't adjust your tune for the change in hardware.
OP: Any mod changing airflow characteristics will only yield tangible benefits when adjusting the tune to account for that. That said, if you're only after power gains, you could probably achieve a similar delta by cutting out the secondary cats.
Before and after virtual dyno. Log 3-5x a day in the same spot for years, I'm pretty consistent at it.
No changes to make on a tune for high flow catted to catless DPs on a scaled 20psi tune with hybrids on 93, I'm more or less maxed for the fuel. If they were holding anything back, would change WGDC or boost with nothing changed in the tune. In essence, only potential change would be back pressure and possibly EGTs. Change in tune changes power, catless DPs barely do anything over high flow catted. If I changed to catless and boost went up, yes, it would make more power, but I'm maxed for 93 octane. I'll dig up the logs tonight if I have time.
Had you compared Cobb catted highflow to stock catted downpipes?Have Cobb catted on for 4+ years. I finally bought some used Macht Schnell catless a couple months ago just to check if catless claims I figured were mostly bunk all these years, actually were.
Catless with flapper closed are no louder than high flow catted with flapper open for cold start. No sound difference on cruise/normal driving. Catless under boost may be a little louder, but raspy sounding to me.
As you'd guess, no change in spool, boost, etc. It's pretty much dictated by boost control, tuning and turbines. Literally maybe a +2whp difference across the board on VD with hybrids at 20psi.
People buy catless because they're cheap and want to believe they're significantly higher performing than high flow catted. Not on these cars. If you already spent the money high flow catted, I wouldn't bother with catless. I put the Cobb's back on if it's any indication. If you're interested in the Macht Schnells anyway, LMK, they're sitting in storage wait to be sold as soon as I have time lol