leecavturbo

had it mapped and torque dives like a fooker @ 5250 from 296ft/lb
to 240@ 6412
no other problems mechanically or setup wise.
its fitted with 284 deg cams atm.... no good?
max power was @ 1.2bar @ 5982
didn't make anymore power with more boost either?

Rs1

iTrader: (1)

Whats the exact cam specs Lee?
imo 284 sounds a bit to much,is that a non turbo cam? Have yo dialled any overlap out at all?
I'd want to be seeing around 260 with 9mm lift(ish) on hydraulics for your spec/target hp.

Rs1

iTrader: (1)

P.S. regardless of cam spec i think you should be looking elsewhere for lack of power,may of asked before but what are the ACT's like?

leecavturbo

freezing

Rs1

iTrader: (1)

thats good.
What was the stop point of mapping then? 330hp?
How close to det is it running?
Something for you to think about...............when setting ignition is it being mapped just by the feedback number the dta is providing? As opposed to running it up with det cans and actually listening for det.................i am going somewhere with this. Imagine at actual tdc the cps is giving a reading of...........anything other than tdc,now whilt mapping it may appear you x amount of advance where as you may well have significantly less/more depending on the calibratuon of the cps. Is it possible for you to manually turn the engine to tdc then get a readout from the dta to see if its close?

leecavturbo

he uses det cans, and it is a mile away from det too, its just the engine can't breathe.

Rs1

iTrader: (1)

Surly running miles away from det is gonna have an effect on max output??
What do you mean the engine can't breathe?

stevieturbo

Could be cam timing, massive overlap, combined with high exhaust back pressures, arent going to do it any favours up top.

They are pretty big cams... they will need dialled in properly to suit your specific combo.

What sort of CR, and what sort of ign timing are you running ??

leecavturbo

7.9:1 . and i should have low ish exhaust back pressure as i'm running a large .86 hotside turbo.
???

stevieturbo

Curious...why such big cams ??

It also seems a little laggy, why the big turbine housing ?

If cam timing etc is fine, and the mapping is good....why not try more boost ?

I assume thats about 1.2bar on your graph ??

leecavturbo

there old cams i had with the engine. i didn't know i would need short duration to do what i want, the smaller housing would only of given me boost earlier and would of been a restriction if i wanted to go higher in the power stakes?
more boost did not produce anymore power?

stevieturbo

Bigger cams, will usually just kill driveability, not affect top end so much.

You really dont need, or want big cams in a turbo engine. Mild or indeed standard just works so much better.


We ran an HKS GT Turbine kit on a Subaru a few years ago, I think it was a GT2540 ( or maybe it was the GT2835....cant rem it was that long ago...might have been the bigger one ya know ) type unit. Dont recall what exhaust side though, but it was on a T25 flange.

It made full boost at under 4000rpm, and made just under 400bhp at around 1.8bar. That was as much as we could get out of it.

Seemed to work pretty well on that engine, which was basically a standard STI with bolt on bits. ( it did have forged rods/pistons, but they dont make power )

Rs1

iTrader: (1)

stevieturbo i think that may be his old power graph.
Lee looking at that graph its not making full boost till after 4.5rpm....whats going on there? That is the boost line is'nt it?
As stevie says the duration on those cams wont be helping overlap,you could try a std ex cam and dial some retard into the inlet...i dont think you'll be able to go as far as the xe inlet mod as if you have higher lift you'll end up clattering the valves. Maybe best of doing a few figures on paper first to see if its viable.