I've had a fabricator fit a stainless steel resonated exhaust system, not unlike the milltek design, but unfortunately have an issue with vibration above about 2750 rpm. I have a Cobra Sport dp fitted. The dp was fitted to the OEM exhaust and I didn't have this issue. I have a feeling the dp is clamped to the stainless steel system at the slightly wrong position, tugging it a little towards the bulkhead and when 2750 rpm is hit the vibration is sufficient to make the dp touch against the bulkhead. I was taking road logs with my JB4 and noted the timing pull was actually higher than prior to fitting the exhaust, the vibrations being picked up as opposed to actual pre-ignition causing the timing pull. I had thought adjusting the clamping position to perhaps even push the dp away from the bulkhead a little, perhaps even fitting a rubber mounted exhaust bracket to the dp, to the section travelling under the car to minimise vibration passed back up the dp or to th end of the long first silencer where it meets the dp and perhaps ****ing about with the heat shielding a bit, to see if a little room can be freed up without compromising things. I can't see anywhere else the stainless steel system is noticeably touching, the rest of the heat shielding under the car looks to have sufficient space between it and the pipe not to be forced into motion, I don't think it's a gas leak from any of the joins, (the welder, Sam, is top notch) and I doubt softer rubber mountings would make much of a difference.
Anybody any ideas or having experienced anything similar? I would be grateful of any knowledge/assistance.
I have a JB4, a forge intercooler, the dp & exhaust, a revo carbon intake, silicon hose & panel filter and a power flex 'road' dogbone insert. I was after a resonated system, something with a little more bark, not something that makes the car perform worse and that leaves the top half of the rev range off limits.
Help!
Edit: I think the metal connection for the lambada sensor is touching the bulkhead when those revs are hit. Possibly a different type of connector on top of the other stuff?
Edit 2: It's not the connector. Managed to get someone to look whilst I revved the engine. Just need the rest of the stuff looked at.
Anybody any ideas or having experienced anything similar? I would be grateful of any knowledge/assistance.
I have a JB4, a forge intercooler, the dp & exhaust, a revo carbon intake, silicon hose & panel filter and a power flex 'road' dogbone insert. I was after a resonated system, something with a little more bark, not something that makes the car perform worse and that leaves the top half of the rev range off limits.
Help!
Edit: I think the metal connection for the lambada sensor is touching the bulkhead when those revs are hit. Possibly a different type of connector on top of the other stuff?
Edit 2: It's not the connector. Managed to get someone to look whilst I revved the engine. Just need the rest of the stuff looked at.
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