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meaning the turbos are too small and 14 psi is the minimum boost it makes at rpm? or what do you mean?

I don't claim to know jack.
I'm not tryin to make you feel stupid...just trying to get u to think..

I suggest a 3D comp so that the timing can be adjusted properly as incorrect timing may cause detonation.

Also You seem to have answered your own question....which proves your not stupid !!!

Maybe you should make a detonation indicator as this may help.

the boost has been so tricky all along, it has changed boost levels many times along the way and has always confused me, so many things have changed along the way also, its too hard to explain, but like recently it made 14psi boost and then i took a turbo off and had it rebuilt and now ive put it back together it makes 8psi, if i disconnect one of the wastegate acctuators it will make 10psi boost though

typically the sytem made about 10psi until i found my intercooler had always been leaking, after fixing that it made 14psi

does it mean my turbos are too small?, i've never been able to heat them to the point where they glow (i tried driving hard along a 16km road up a hill once and only got the slightest glow from one of the turbos)

once it was running 10psi. Then i used washers to lighten the pre load on the wastegate acctuators and it made 7psi. I took the washers out again and it still made 7psi.

Things like that have left me quite confused and unable to control the boost well

I would suggest checking the wastegate accuators. Could be a split diaphragm?

These can act as bleeds from time to time. . .

For a cheap fix, try looking at et pulsar pistons. I had them on my a14et so I think they will fit the a15.They have thicker ring lands and thicker piston face. Also have moly rings from memory. They will lower the compression a bit. The pin required no machining to fit.

Just to ease this a little woudnt one turbo be easier to manage than two turbos. I do understand not as cool with one turbo.

Provided your wastegate actuators are working properly, the reason you can't keep boost down is because the internal wastegates are too small. You can get those things high flowed which will help, or you may need to use an external gate if you intent on keeping those turbos.

Usually a sign of an outflowed wastegate though, is that boost will reach the desired level and then begin to climb with revs. If boost jumps from 0 straight to ~14psi then I'd be looking elsewhere.

Another thing worth noting is that if you have outflowed your wastegates by so much that it is reaching 14psi then I'd say you have some seriously undersized turbos which will be miles out of their efficiency range and therefore creating lots more heat.

I reckon being a M.E should give you the knowledge to build a reliable turbo A-series!

ahhhh ok, i see, so high flowing a turbo means increasing the waste gate size?

when he rebuilt the turbo he said he high flowed it (my brother picked it up so i didnt get to ask about it)

boost will build at high revs.. so maybe the wastegate is too small

i found out the turbos are in fact the same as charade ones, being from a 1000cc motor, you would think 2 would be fine on a 1.5

being a mech eng doesnt help... sure i could calculate a whole bunch of crap but what i have learnt has been from posting here and working on cars, theres plenty of mech eng's that couldnt tell you how a motor works at all

Sorry for using the generic term "high flow", what I meant was that they can bore out the wastegate diameter and fit a larger flap for more accurate boost control. Normal high flowing involves bigger wheels and bored out housings etc. If you do infact have a "high flowed" turbo then you essentially have 2 different turbos on the thing now. You wouldn't get proper highflowing and a reco for any less than $1000 so maybe you should go ask exactly what has been done?

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Maybe true, but being a mechanical engineer who is interested in cars, didn't you find that as you learnt all your fluid mechanics and thermodynamics etc, that you kept relating it to your cars and thinking about how they worked?

regarding mech eng:

definately, but for example that doesn't tell me what rings to use, or why i've been damaging rings. I still either have to research/calculate or simply ask for other peoples experience on here

but of course it helped me know what i wanted to do with pipework and exhaust manifolds and various other things

i think the mech eng thing mainly promoted a mind set, a way to work through problems and try to understand em, but at the end of the day you cant beat others experience