Boost Kills - Warning

[Jimbo]

good stuff... i dunno what im saying cause im drungk but hey... interesting thread all the same!

lol, looksh lik ill have a few thitngs to think about befor i play to much wiht boosth. thanks BDA

Ken, your typing's slurred mate! Go an have a lie down

[Kenneth]

Ken, your typing's slurred mate! Go an have a lie down

lol, yeah things were interesting at that point... because i touch type, i have problems typing drunk. Got too frustrating trying to correct my spelling, so I just gave up

[aaron68nz]

boost I was running was less than 1 bar, but the aggresive way it comes on is probably more the problem.

So running 0.9ish maximum I'm maybee best to leave in factory exhaust to prevent too fast a boost build up at low engine rpms. By the way have many people given regard to the fuel filter as I don't know how much effect on fuel flow a dirty one might have. Mechanics often say this filter is too often over looked.

[-LegnumVR4-]

Good to have someone looking into these engines. Thanks Dave for the pic and info

[ako]

The one thought that comes into mind is just how is it leaning out so easily - 6 X 390cc injectors is a LOT of fuel, sure its not just excessive inlet temps causing detonation/melted pistons as opposed to going lean?

But still, I'm bloody surprised the thing survived as long as it did in the condition its in - would have loved to have cracked open my old 6A12, chances are it was worse

[zentac]

I dont think its fueling as Ive leaned mine off across the whole range and Im running more bhp than most (except the nos people) unless its down to flow and the pump cant cope as mine is an uprated pump.

[enigma]

Nope.....uprated pump for me

[ako]

Must be heat, or maybe timing related then.

One thing though - I'm not sure with the 6A13, but I know on my old engine it had a solenoid for boost control hooked into the workings of things. When the ECU heard knocking, itd pull back the boost - a LOT if need be. Running 91 octane once saw it pull boost right back to 7psi (From the 13-14psi it normally sat at) - fuel which shouldnt have been in there at all, but my GF meant well filling the car up at least

Thing that comes to mind is if you're running new boost control - as the majority do - a lot of people either take this solenoid out, or if they have EBC it ends up compensating for what the factory system is trying to do.

Its weird.. On the GTO / 3000GT's, their fuel/airflow cut doesn't occur until the ecu is registering 115% injector duty cycle.... 115%!!! Funny thing is though - the engines in them are incredibly prone to knocking, or detonation as its properly called. Throwing a datalogger on them will show them detonating, even in totally stock form in some cases - or at the other end of the spectrum, some can throw 15psi into them with no adverse effects whatsoever. On the unfortunate ones, the ECU will detect it some of the time, and try and pull timing to offset matters, but its just a bandaid. They still go "pop" if its left uncorrected.

Now... Why the hell did I write all that dribble? Simple.... I wonder just how many people on here are putting the usual "0.9 - 1 Bar boost" and assuming all will be fine - remember, those are damn tiny turbos, I know that at the compressor outlet my temperatures were throught the roof. (Only thing saving my engine was a novelty oversized intercooler ) ... When there could be almost inaudible detonation occuring? If you've got a bung knock sensor, or its unable to hear due to any number of things, you could be quietly, slowly killing off your rather expensive engine. Daves is just proof of this - the numbers say it can handle 400hp on the stock fuelling, but you can't rely on pulled timing to save an engine alone.

So... Who actually monitors anything on their engines? We're just starting to use the dataloggers to their full potential here, and now that I've seen them in action, just cringe at the "trial and error" methods used before.