gkane

Hi

Not really a technical problem, but a newbie question I had a search, but sometimes its difficult to describe sounds.

At certain rpms my engine/exhaust note changes from a smooth rotary into an odd rapid stuttering. Kind of like its doing a burp.

I've heard other rx7s make the same sounds so i know it must be fairly normal, although i hear it more often on large ported engines - every so often in between the "brap" cycles it stutters for a second or so then carries on.

Happens most often on decel in low gears, and i can catch it with the throttle so it will do it constantly until i accelerate again or take my foot off the pedal. Or also when i pull away very slowly in first and get to ~1500rpm.

I like it, its not annoying or anything, just curious about what causes it? My first thought was maybe a mild street port? (engine was rebuilt in japan before i took ownership, but no paperwork) but then it had the stock downpipe, cat and air box, so.... maybe its something rotaries just do?

Again, sorry if its a dumb question!

gxlbiscuit

mine is doing this whenever im in boost i have more than enough gas... i adjusted the timing yesterday. it worked fine for a little bit. but its back again just a little less now. im wondering if my CAS wiring is compromised.. my car sound great then it will randomly braaaaaap and burb under boost. I cant perfect my idle either...Its currently either too high or two low. i have no bacv or iacv just got the car back on the road its reminding me why i bought a honda.... (its old)