mtnman82

Just wondering if this is normal, or if I should be looking for a leak somewhere (car seems to run good though)? After I installed the 3" exhaust (no cat, straight thru muffler) the turbo spool seems quite a bit more predominant. Sometimes if I'm just cruising real mellow, shifting from 3-4 at ~3000rpm or so (turbo just spooled?) I hear a whine going down in pitch very similar to a police siren - freaked me out the first time or two I heard it (thought I was going to get pulled over until I saw no one behind me).

I'm guessing this is just due to the more open exhaust?

alxdgr8

yep, perfectly normal. as long as the turbo doesn't sound like a dentist drill you're ok.

drift a 944

I have basically the same setup on my 86 951, and I can barely hear the turbo whine.

However, when I took my muffler off, and just ran it straight pipe (3" no cat no muffler) I could hear the turbo whine loud and clear, and it did sound like it spooled up very early, like at half throttle or more at any point in time.

So either your muffler is much more straight-through flowing than mine, or you do have an exhaust leak somewhere.

This is just my guess though, Im still learning a lot about these 951's.

76 911s

Thats normal, I've got a Lindsey 3" with a test pipe and Magnaflow muffler. Theres lots of turbo whistle under even light loads. When I put the cat in for emissions, its way quieter as it acts as a resonator. Your stock cat and muffler are huge, thats why you don't hear much turbo.

mtnman82

Thanks guys, just wanting to make sure ... I've got the Fabspeed system FWIW. It's also spitting out the black soot when I start it up in the mornings - making a mess in the driveway just outside the garage (I think it'll clean up, but wifey isn't too happy about it at the moment). Guess that's just part of the deal too...........

76 911s

Yea about that....I walked behind my car one morning after I got it in a pair of Dickies khaki shorts. I never did that again...