40 replies to this topic

[Simon]

Will pass by the tuner in the next few days to get a copy for you guys. Didn't get a chance to put the 02 sensor in but I have also purchased a Sard FPR and should arrive next week. I figured I would put it all in when I get a free weekend.

Once again, I really appreciate all your feed-back and thoughts.

[nwr31]

Its not that shocking, its a very common boost behaviour and power output by an engine thats equipped with relatively small turbo and a bleed valve.

Anyhow, heres another example shows afr and boost. Notice how the power reaches almost its maximum around 4800rpm and stays pretty flat up to almost 6000 and starts droping over 6k. Air fuel ratio is kept around 12:1.

well its the worst boost curve ive seen in along time and yes i know what happens when a small snail chokes on the topend. all im saying is that with the info supplied in that graph (ie, no afr's..) boost taper would be the reason for the big power drop off. bleeders are useless things, much better to have a variable checkvalve type mbc (turbotech type)

as for that other graph, i think its getting on the lean side, in my experience keeping afr's below 12 (around 11.7) is the way to go. except on spool-up, then you can go just over 12 briefly. of course it all depends on amount ign advance, but even then staying under 12 is allways best imo.

Edited by nwr31, 06 July 2011 - 10:28 AM.

[GSR]

as for that other graph, i think its getting on the lean side, in my experience keeping afr's below 12 (around 11.7) is the way to go. except on spool-up, then you can go just over 12 briefly. of course it all depends on amount ign advance, but even then staying under 12 is allways best imo.

yes I partially agree with you on that one but thats beside my point I just wanted to show that even thou air-fuel is taken care of in the top end and boost is somewhat stable lol the characteristics of the power output is still the same. Makes almost peak power at just over 4.5k and stays pretty flat to 6k (turbo plays main role here). Thats exactly how he described his problem; plus being rich.

Lets see what his dyno printout will look like if he gets a chance to get a hold of it.

And my suggestion to you Simon is, if you want more top end, get a 14b or 16g td05h and you'll have power almost to the redline

Edited by GSR, 06 July 2011 - 11:07 AM.

[BMGTZ]

yes I partially agree with you on that one but thats beside my point I just wanted to show that even thou air-fuel is taken care of in the top end and boost is somewhat stable lol the characteristics of the power output is still the same. Makes almost peak power at just over 4.5k and stays pretty flat to 6k (turbo plays main role here). Thats exactly how he described his problem; plus being rich.

Lets see what his dyno printout will look like if he gets a chance to get a hold of it.

And my suggestion to you Simon is, if you want more top end, get a 14b or 16g td05h and you'll have power almost to the redline

my pick ....14b as it retains low end response and delivers the extra punch where the std turbo tapers off.

needs a bit of porting in the exhaust housing and some clean up of the compressor housing out let and it will be nice as a tractable streeter

[Smutt]

TD04-L should be good for a 13.75 sec qtr at say.... 98 mph
with a dual dump etc etc..

[Simon]

Iv actually got a td05 16g (big) sitting in the corner of my spare room (along with cp pistons and spool rods) but was going to put that on when I rebuild the engine at the end of the year. Just want to get it running right while iv still got rego on it and enjoy it for the next few months before it comes off the road.

[nwr31]

nice!

[Smutt]

FYI my standard GSR AFM maxed out at 163 KW ATW

note: I am only talking about the AFM... do not assume other supporting part were stock because they weren't

[nwr31]

jeez i thought they might have had a bit more in them than that (only going on the later evo afm's), but yeah thats another reason why im getting rid of mine.

[Smutt]

That aint too bad... 163kw ATW was good for a 12.92

1G DSM MAS
A stock, unhacked 1G DSM MAS will not accurately report frequencies above 2000hz. That frequency represents roughly 380 cfm of volumetric airflow. At standard temperature and sea level pressure, thats about 210 gm/sec (28 lb/min) of mass airflow.

2G DSM MAS (3000GT VR4 EVO 1-3)
A stock, unhacked 2G DSM MAS, around 2700hz, will do roughly 680 cfm and 50 lb/min

EVO 8 MAS
Designed to operate even higher... around 3000hz, has it been maxed out yet? 890 cfm and 66 lb/min..

[nwr31]

i think around 300kW is maxing out a late evo afm, after that people tend to get real serious & get rid of them too.

[GSR]

Thats because its the same as a naturally aspirated 4g93 afm. Evo 1-3 unit is a direct replacement, evo 6-9 unit requires different plug but still easy enough to do since pins are in the same order; and adjustments in the ecu for both units via ecmlink or tunerpro is a joke.

Steve at SKR makes 330kw+ in his evo with gt3076 and 39psi of boost. At the time I was there, he wasnt eyeing to get rid of it as it wasnt near its limit yet.

[Smutt]

Steve at SKR makes 330kw+ in his evo with gt3076 and 39psi of boost. At the time I was there, he wasnt eyeing to get rid of it as it wasnt near its limit yet.

+1 "change it only if it has maxed out! hehe"

[nwr31]

yeah & im aiming for a lot more than 163kW so in the bin it goes

[Simon]

What would happen if I put a evo AFM on?

[GSR]

The car would run lean so you would need to get either a evo ecu and injectors or get your ecu socketed and new chip written to suit.

[DOUGMO]

+1 "change it only if it has maxed out! hehe"

Just because it may not be maxed out, doesnt mean its not a restriction though

[Smutt]

I agree with you Dougmo.
However, I like to push what I have until I hit a wall then change one thing at a time and progress that way with my modifications.

[Simon]

Problem was as simple as a few boost leaks.

One from the bov and another from a silicon pipe that tore through (massive tear).

Now back on the dyno to check power.