supercharged 4.0 with current hole in bonnet...

[mr 63x]

hi guys..new to this as work takes up too much time..but..any of you had exp of sprchgin'a rover v8..? all very fine till 5500 revs in 4th..then loads of "pinking ????" obviously ease off a tad then do 5th..but..as 5000 revs(approx 150 mph on clock)same pooh happens. have tried tuned chip but thats worse than std one !!! could it be larger injectors needed?? dont want to hand over to a garage yet,as could be a licence to bankrupt me!!! strangely tho..all fantastic till this point

[tahiti450]

Injector saturation sounds like a pretty likley cause if air flow is outstripping max fuel supply, but the same thing would happen at full throttle in any gear at a given rpm (IIRC max injector period usually happens around peak torque rather than max power, though of course air flow will be max at peak power). I presume the ECU is appropriately re-mapped, both fuelling and ignition timing?? if it were injector capacity then a quick and crude fix would be upping the fuel pressure ( could help as a diagnostic trial anyway). If its not that then it must be timing....

You mention a tuned chip, sounds like you are referring to something off-the-shelf? I would have thought you would need a custom designed map and or an adjustable set up for something so exotic, IIRC Mark Adams does a range of very special ECUs.

>> Edited by tahiti450 on Wednesday 27th April 01:21 copied across from gen TVR stuff

[mr 63x]

thanks for advice..think could be top end fuel pressure as only happens in high rev 4th and 5th...6k thro other gears(dry surface only!!!!)and not a rattle.......just teeth!

[Steve_T]

Suggest you contact Peter Humphries (GreenV8S) he's super charged his motor recently, so may well have been through the same issues. You'd also do well to talk to Mark Adams, if you haven't already spoken to him.

Cheers,

Steve.