turbo probs with 4agte

[rossco]

ok. i'm starting to hate this car and should probably just sell it to someone who knows what they're doing. anyway i'll persevere for now.

i'm having problems with the boost on my ae92 trueno. the engine (4agte) still goes hard and the turbo is working but i'm suffering from some serious lag. when i put my foot down the car stops at around 3-4000 revs and has a think for a few seconds before boosting. sounds like its just spooling for ages.
any ideas how to fix that? what could it be?

anything appreciated, cheers.

[Bazda]

agh, what engine are u running? map or afm?
when i first got mine running i also had this problem, i stuck in a bigger fuel pump and most of it went away. Then i stuck in blue top cams and it all went away, still has lag but doesnt get that nasty part where it does nothing.
I know another guy with the same problem running a normal t25, but his eng light was on so it prob had the timing retarted heaps which can also make it do that.

what turbo u running?

[Dr-X]

I would also check your ignition timing

[Bazda]

i run 0 degress initial timing on mine.

[Twolitre]

I wouldn't have thought the cams would have anything to do with it? I assume you have an aftermarket boost gauge? Is the turbo making full boost right the way through your flatspot? and when was the last time you replaced your leads, plugs, fuel filter etc?

[Bazda]

cams helped with the lag sorry.
flat spot was gone once I put a rx7 turbo fuel pump on and clicked the afm over 3 clicks richer

[rossco]

i don't have a boost guage hooked up to it yet. it's been stolen and all that stuff went for good. i've spent heaps of money repairing the engine and wanted to get all that sorted before splashing out on guages, timers etc.
so yeah all new plugs, leads, filters etc.
turbo is garret but unsure which model. probably t25. how can i tell?

[Silent Knight]

Look on the turbo housing if it is a Garett T25 then it will most probably say so on the side of the turbo housing.

[rossco]

i should check out the fuel pump anyway. cheers guys.

[rossco]

cool. cheers silent knight.

[Bazda]

I have a rx7 turbo pump that will fit straight into your car as i was running it in my car but upgraded to a 500hp+ one.
this supplied more than enough fuel on 18psi.

[Lloyd]

Sell it to me Bolt straight in?

[NZ_AE86]

If the car in question is the one in you pic, it will not be the fuel pump or the cams! That car used to go just fine! Have you changed anything since you bought it?

[Bazda]

maybe its to do with the cooler u are running or the way u have the piping set up...

is it map or afm??

when i first got my conversion done I had this same prob, and this other guy i know running the same eng as me and a t25 also had the exact problem, only thing diff to my car and his is the fuel pump now.

[Volatile]

I'm 90% sure its AFM

[Bazda]

I'm 90% sure its AFM

in that case are u running the afm inline with the i/c piping? (blowing through it),

[rossco]

yeah it's afm. they're the early ones right? big port?

[rossco]

If the car in question is the one in you pic, it will not be the fuel pump or the cams! That car used to go just fine! Have you changed anything since you bought it?

yeah it got stolen and butchered. the boys at L.Alexander have spent months tryin to fix it. i've tried to keep pretty much the same setup.
did you know colin?

[Bazda]

go click your afm over 2 clicks anticlockwise which makes it richer.