superduperman

When I accelerate under 3k and still in vaccum i hear this clinging sound. Im not sure if it's my intercooler pipes banging against my frame or denation. So is it possible to denoate w/o boosting?

2000vsm

yeah, how you think normal cars without turbo detonate?

Pengo

detonation isn't something unique to only boosted cars

superduperman

Well I dont understand how Im detonating in vaccum? My setup is a 12:1 FMU/Missing Link/MSD Inline fuel pump which should definetly suffice 5.5 PSI. Anyone got any ideas as to what could be wrong?

XDEep

well what is detonating? mixture igniting before its supposed to. so there can be many reasons like heat, running lean, timing, tuning..

superduperman

Do you think running colder plugs would help? Im using stockies right now.

Mase

what engine management are you running?

superduperman

12:1 FMU, Inline Fuel Pump and please dont reccomend the hack or standalone

JT

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by superduperman &raquo;</TD></TR><TR><TD CLASS="quote">Well I dont understand how Im detonating in vaccum? My setup is a 12:1 FMU/Missing Link/MSD Inline fuel pump which should definetly suffice 5.5 PSI. Anyone got any ideas as to what could be wrong?</TD></TR></TABLE>

Do you still have the stock FPR? If not, you should. Otherwise, the fuel pressure transition in vacuum will be kind of flat. The 12:1 FMU might not be able to handle smooth fuel pressure transition in vacuum. That's what the stock FPR is for.

Pengo

whats ur ignition timing set at?

Mase

if your ignition timing is near 16 degrees btdc, i highly doubt you are detonating under vac.

XDEep

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by superduperman &raquo;</TD></TR><TR><TD CLASS="quote">Do you think running colder plugs would help? Im using stockies right now.</TD></TR></TABLE>

a possibility. a colder plug is meant to extract more heat from the chamber. have you been checking the plugs?

Teg4e

probably not detonation that low in the power band, and in vaccuum. Technically, N/A cars are probably at 0 vac/boost if they're deonating...i.e. WOT.

superduperman

As I pay more attentino to the sound it sounds more like metal banging against metel.....kind of a quick rattling type of sound. Im starting to think it might be my intercooler pipes banging against the frame or something. Anyone else got any ideas?

boosted92

Try wrapping some old rags around any IC pipes near the frame and go driving and see if it goes away. If you have access to some race gas flush the tank and dump in a bit and drive down the block and see if it still does it.

civperc

have you taken a look/listen in the engine bay and front end area while the car's idleing?

superduperman

Yah I have and nothing seems out of the oridinary. It detonation loud?