why is the power so low. I was expecting the same power from less boost or more power from this boost level. Power drops off up top
it was about 100 degrees that day.

The motor is a GSR with ITR IM.
Drag Turbo kit.
2.5 DP and exhaust no cat SS muffler.
21 psi falling off to 19

I dont know the specs on the turbo but its a t3 / to4e

here is the dyno chart at 20 psi
http://mail.google.com/mail/?v...ffe31


and here is the dyno chart at 16 psi
http://mail.google.com/mail/?v...ffe31


i think the graph at 16 psi looks much better, and the boost doesnt fall off but I still think it should have made more power even at that level. (based on what other people are posting)


let me know what u guys think. thanks in advance.

 

also ...


9:1 pistons
rods


ignition timing up top is around 16 - 17*
A/F is 11.8ish

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by not2slo128 &raquo;</TD></TR><TR><TD CLASS="quote">2.5 DP and exhaust no cat SS muffler.</TD></TR></TABLE>

Thats the thing thats hurting you right there

 

Get a better ic, those drag ic's are crap.

 

Thanks guys. I heard about those intercoolers... and the piping is steel i think.

but about the exhaust piping ... how much does that really matter ?

 

also

how do i post the graph so you can see it in the post?


i see "attach image" but it doesn't seem to work. i think it's only for iomages on web servers.

can i upload stuff from my desktop?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">Get a better ic, those drag ic's are crap.</TD></TR></TABLE>

i had a drag ic but i sold it to my friend to get a bigger better 1. whats wrong with the drag ic? let me know, he might want to sell it and get somethin else then.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by not2slo128 &raquo;</TD></TR><TR><TD CLASS="quote">

2.5 DP and exhaust no cat SS muffler.</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BoostedEG6 &raquo;</TD></TR><TR><TD CLASS="quote">

Thats the thing thats hurting you right there</TD></TR></TABLE>

 

thanks for the replies guys...

i didnt realize that the exhuast piping matters that much...

any other opinions...

 

an 11.8 AFR is pretty damn rich...

why not lean it out to around 12.5 or so and see what she makes...


what are you tuning with? i dont see mention of injectors either. if youre running off an fmu and fuel pump with a missing link for the map sensor, that will explain the lack of power too.

 

hahaha...


20 psi on FMU ... lolol .. that would last like 2 days..

i forgot to mention I use Uberdata with 750cc injectors

i think 12.5 at 20 psi is to lean. imo

 

11.8:1 is not all that rich. It's not going to pick up more than 5-10hp TOPS leaning it out more.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">11.8:1 is not all that rich. It's not going to pick up more than 5-10hp TOPS leaning it out more.</TD></TR></TABLE>

i agree.... not worth it... high 11's is where i'm gonna keep it.

So suppose I switch to a 3" DP & exhaust, how much HP/TQ do you think i'll gain?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by not2slo128 &raquo;</TD></TR><TR><TD CLASS="quote">

i agree.... not worth it... high 11's is where i'm gonna keep it.

So suppose I switch to a 3" DP & exhaust, how much HP/TQ do you think i'll gain?</TD></TR></TABLE>
at the amount of boost your seeing, going to 3" DP and 3"full exhaust I think about 30-35whp

 

wow! thats a lot! thats what i like to hear... thanks.

will the increase be mostly at high rpm or everywhere, cuz the graph shows something is choking me up specifically at high rpm.

 

bigger exhaust will definatly free up some top end horsepower.

what A/R is the exhaust housing on the turbo?

i think drags come with .63 which should be on there, but if for some reason it is a .48 it will kill the power on the top end on a gsr.

 

like i said i dont know about the ar ... i think you are right tho; .63 sounds right , the compressor is probably .60

can anyone confirm?

 

yea u should be making a bit more with 20 pounds, well obviously, lol im making 306-220 on like 9.5-10 pounds, a/f is around 12:something, on a stock gsr, but also using a ram horn and a 3 inch down pipe and full 3 inch exhaust, try making it breathe a lil bit better. hope things work out for you

 

i think you are choking at high rpm because you are only on 17 degrees of timing!

i was 12:1 AFR the entire pull on a stock GSR on 7.5lbs (t3/T4 63t) and made 287whp, and i had a 2.5" downpipe. some of it may be you are on a log manifold, but i was on a love-fab mini me. i would say get an EGT gauge on there, and add some more timing! i was on 24 degrees and my EGT's were still fine! then my BOV broke, and didnt open, and i had CRAZY crankcase pressure, so my ringlands said bye bye.

 

HAHAHA, wait, so you just add timing until the EGT's are too high? What's too high on EGT's?

You think your ringlands took a **** because the blow off valve didn't open? Dude, you need to find a tuner when you get it put back together...

 

be sure to turn down the boost before putting your 3" exhaust system, as it will creat more boost dues to the high flow. it cranked up my boost about four pounds higher when i got it done on my ls turbo hatch.. just my 2 cents...

 

17 degrees at 20 psi is pretty advanced imo. According to the plugs that is the most the engine likes to run safely.

I think a messed up BOV would mess up the turbo not the rings, since instead of releasing the sudden jolt of air it sends it into the compressor housing that is spinning in the opposite direction.

24 degrees is fine for 8 psi .. but not for 20 ...


What SPNFEDEH said sounds plausible...gotta save up some doe and the good stuff...

new DP
new MANI
new IC & piping

damn...didnt realize it would matter that much.

 

thanx.

+ 4 lbs compared to what?


stock or another aftermarket system?

 

like others said...

3" downpipe and 3" full exhaust
Better intercooler
and cooler air temps (100* is hot outside!)

and you should be 375+whp


sounds like the turbo might be a little small if its dropping in the high revs. double check what size it is.

 

ok.. i will check it when i change the other stuff... for now its a mystery... i can't find the specs on the compressor side of the drag kit. exhaust is .63.

thanks to everyone for their suggestions... (even the people whos advice would have blown up my engine =P)

i didnt really post for years cuz i saw mad ppl get flamed on (and i was less knowledgeable)... but its not so bad ... ill buy the things i mentioned in the post above and update you guys with the new (and hopefully improved) dyno sheet.