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I've honestly always overlooked the 20g for the dom1.5. What you're describing sounds like what I'm looking for. You're on the stock block still yea?

I personally think the TD05 20G is probably the most fun street turbo for the price. I am no longer on the stock block. After lifting heads, I just built a block and sold the old one.
 

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YYZ's engine: Who are you talking to right now? Who is it you think you see? Do you know how much whp I make? I mean, even if I told you, you wouldn't believe it. Do you know what would happen if I suddenly decided to stop rotating? A rod big enough that it could be listed on the NASDAQ goes straight through my block. Disappears! It ceases to exist without me. No, you clearly don't know who you're talking to, so let me clue you in. I am not in danger. I am the danger. Some other guy goes WOT and gets some FBK and you think that can't happen to me? No. I am the one who knocks!

<apologies, I have vacation starting tomorrow and am getting giddy>
Uhhhh...


Aaaaanyway, OP if you're looking for ~300whp, injectors, fuel pump, FPR, and tune for E85 will easily get you there. I have a buddy with Cobb intake, DP, flex fuel/fueling on stock turbo, and he put down 325whp/385wtq at 4500feet on a dynojet.
 

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That's what OTS should get . . .
 

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I am guessing. The tuner was able to get that out of a WRX on an E85 tune.

It was not about the numbers. It was about that the stock turbo is capable of a lot with the supporting mods. E85 is where its at. Without even trying I was over 400WTQ.

HP sells cars. TQ wins races.
 

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Discussion Starter #27
Reason im looking for different turbo is because i dont want stock turbo to turn into blow dryer, can somebody tell the max efficient boost for stock vf48?
 

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Reason im looking for different turbo is because i dont want stock turbo to turn into blow dryer, can somebody tell the max efficient boost for stock vf48?
a gtx3071r compressor almost perfectly matches the volumetric efficiency of our stock heads up to about 28psi @ 5800rpm. imo stock location, apt gtx3071r is perfect and is more than enough to max out your block. many videos out there of cars tuned w the 3071 or 3076... all running nice, safe, low boost and making good power w quick spool. 16-17psi @ 375 whp give or take

so many manufacturers out there that cant show u a compressor map... then all u have to go off of is "here-say". ill believe the numbers any day over a few opinions
 

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Why give us [email protected]?
Why not what it will do at 7K where stock redline is?
Both might be better :)

Seems you are implying you can't run 28PSI higher - not that I do or don't want to run 28psi.
 

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Reason im looking for different turbo is because i dont want stock turbo to turn into blow dryer, can somebody tell the max efficient boost for stock vf48?
I think you should just do some basic bolt ons and get a a proper tune before you start thinking about any turbo upgrades.
 

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Off-topic, my apologies... Just couldn't justify creating anew thread for this:

Is there a thread where users list their mods/mileage? I am having an inner struggle about whether to modify my '15 STI or not since I have the 100k bumper-to-bumper powertrain warranty and I am realllly worried about ringland or rod failure.

If I were to modify, it would be: Cobb AP, Cobb SF intake, Church Protune. I assume you can always ask for a super-conservative, reliable, safe tune... no?
 

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Off-topic, my apologies... Just couldn't justify creating anew thread for this:

Is there a thread where users list their mods/mileage? I am having an inner struggle about whether to modify my '15 STI or not since I have the 100k bumper-to-bumper powertrain warranty and I am realllly worried about ringland or rod failure.

If I were to modify, it would be: Cobb AP, Cobb SF intake, Church Protune. I assume you can always ask for a super-conservative, reliable, safe tune... no?
http://www.iwsti.com/forums/power-bragging/

Have fun going through all of the pages.

Keep in mind Dynos used, Elevation, Ambient temps that these cars are claiming these results.
 

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Discussion Starter #36
Off-topic, my apologies... Just couldn't justify creating anew thread for this:

Is there a thread where users list their mods/mileage? I am having an inner struggle about whether to modify my '15 STI or not since I have the 100k bumper-to-bumper powertrain warranty and I am realllly worried about ringland or rod failure.

If I were to modify, it would be: Cobb AP, Cobb SF intake, Church Protune. I assume you can always ask for a super-conservative, reliable, safe tune... no?
Why are you worrying if you have 100k warranty?
If you start modding your car you will be even more paranoid that if something happens warranty not gonna cover it. Plus you paid for the warranty so just drive the car and enjoy it
 

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Why give us [email protected]?
Why not what it will do at 7K where stock redline is?
Both might be better :)

Seems you are implying you can't run 28PSI higher - not that I do or don't want to run 28psi.
double checked my notes and ive got 5900, not 5800. I used this number in my VE calculations because this is basically the point at whick our stock heads, at a constant intake pressure, stop increasing in flow. there is no increase in airflow anywhere above about 5900rpm (+\- 100) hence no reason to be reving any higher and not shifting.

proof of this can be found on any datalog that includes calculated load, MAP pressure and throttle position.
calculated load = MAF (g/sec) x RPM
at constant manifold pressure (max boost) and WOT, calculated load levels off and stops increasing right around 5900RPM. this can also be seen in most dyno charts as the point of max HP.

the VE for our stock heads is almost dead nuts down the center of max effeciency on the map for the gtx3071r... and right around 28psi is where efficency starts dropping significantly

just cuz an ad for a turbo from manufacturer X says its a 70lb turbo dont mean its efficient @ 70lbs ;)
 

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For those looking for the volumetric efficency of our stock engines so you can actually use a compressor map - her ya go. it should be pretty darn close. within +\-2% or so on any compressor map. variations due to constants used in my calculations include:

intake temp post intercooler 125dF
pressure drop over intercooler 1.5" (this is posted pressure drop for an ETS FMIC which almost identically matches the stock intercooler)
inlet pressure pre turbo: -.5" (the only value i could not locate a true constant so i largly assumed. in the final equation, any variation to this makes very little effect)
average volumetric efficiency: 85% (fully built heads/ect. can run up near 100%)

Below are the estimated VE numbers @ 5900 RPM. stock block, stock heads
dP = differential pressure (used on left side of compressor map) high estimate
estimated stock heads, stock car @ 85% VE
estimated fully built heads @ 100% VE

20PSI - 2.5" dP
41.04lbs @ 100% VE
34.89lbs @ 85% VE

25PSI - 2.9" dP
46.95lbs @ 100% VE
39.91lbs @ 85% VE

30PSI - 3.3" dP
52.87lbs @ 100% VE
44.94lbs @ 85% VE

35PSI - 3.3" dP
58.78lbs @ 100% VE
49.76lbs @ 85% VE

40PSI - 3.3" dP
64.70lbs @ 100% VE
54.99lbs @ 100% VE

45PSI - 3.3" dP
70lbs @ 100% VE
59.5lbs @ 85% VE
 

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Why give us [email protected]?
Why not what it will do at 7K where stock redline is?
Both might be better :)

Seems you are implying you can't run 28PSI higher - not that I do or don't want to run 28psi.
double checked my notes and ive got 5900, not 5800. I used this number in my VE calculations because this is basically the point at whick our stock heads, at a constant intake pressure, stop increasing in flow. there is no increase in airflow anywhere above about 5900rpm (+\- 100) hence no reason to be reving any higher and not shifting.
Ok, so you are at maximum power and it wont go higher. That's not a reason to shift though because you lower it shifting early, and you loose time doing it, and force more early shifts down the road.

proof of this can be found on any datalog that includes calculated load, MAP pressure and throttle position.
calculated load = MAF (g/sec) x RPM
at constant manifold pressure (max boost) and WOT, calculated load levels off and stops increasing right around 5900RPM. this can also be seen in most dyno charts as the point of max HP.

the VE for our stock heads is almost dead nuts down the center of max effeciency on the map for the gtx3071r... and right around 28psi is where efficency starts dropping significantly
Again, seems to me, max power is max power, and most of us with significant turbo upgrades run less boost and app constant power out to redline. It also seems to me you are pushing your build - and you would benefit having built heads.

But, I'm no expert. Please explain if I am wrong.
 

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Ok, so you are at maximum power and it wont go higher. That's not a reason to shift though because you lower it shifting early, and you loose time doing it, and force more early shifts down the road
you could quite possibly be correct :) im not really sure what would yeild a quicker 1/8 or 1/ per say, im def not a dragstrip guy

and if you have a stock head and w increased power output to full redline on a dyno... then its either the driver on the dyno or the tune has been adjusted in a way that doesnt yield 100% requested load until close to redline - this can be done in a few different ways to stretch out power output to show a full graph, by wouldnt u want it all to come on sooner? unless its a very high HP application and that much power down low would just be too much

either way, you can reach max boost (and it holds there) far before redline, and if u smash that pedal to the floor (100% requested load) your gonna run out of runway by the time u hit 6k ish no matter what turbo u have on (unless u got on a monster turbo running very high boost and maybe u havent hit max boost yet) the heads literally cannot flow anymore.
 
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