GT2871 USERS. SR motor

[z2roll4life7]

also i really dont no how much Fuel Pressure is at on the top end
all i did was i took off the vaccum line on my FPR adjust it to 49 psi at idle put the line back on and it droped down near the 30s

[z2roll4life7]

Originally Posted by S13 curtis

im sorry but there is no way in hell those are 370cc injectors, you must be running upward of 100psi of fuel pressure. def at 17psi on a 2871. or your injectors are bigger than u think. i had 370 injectors on my 2871r at first with 55-60psi of pressure and it would be around 98-99% duty cycle 11.8-12.1 AFR and I WAS ON 10 POUNDS!!!!! I cant imagine 17psi. fuck i can barely run 17psi on E-85 with 740cc injectors.

they came with the motor and this was on a dynojet so it probally off by 20hp but i swear thats what my AEM wideband showed
when it spiked it jumped up but not bad at all and we heard no knocks next time ill bring a video camera also
i Thought e-85 needs like 30% more fuel? so 740s wouldnt cut it?

[S13 curtis]

^ if your wide band is reading 11.7 AFR with those injectors it must be broken

[z2roll4life7]

Originally Posted by S13 curtis

^ if your wide band is reading 11.7 AFR with those injectors it must be broken

Maybe

But my new injectors are on the way so it wont matter soon lol

[S13 curtis]

Originally Posted by z2roll4life7

i Thought e-85 needs like 30% more fuel? so 740s wouldnt cut it?

nope its not maxxed out but my duty cycle was getting pretty high 92%

im also on the stock fuel pressure im getting an adjustable FPR and moving up to 23-25psi. my setup should net about 440-460 ish once its done my setup is different than anyone else on this forum. you guys will see soon.

[codyace]

Originally Posted by S13 curtis

fuck i can barely run 17psi on E-85 with 19* timing and 740cc injectors.

19 degrees base timing or top end?

[S13 curtis]

Originally Posted by codyace

19 degrees base timing or top end?

WOT. shit pulls hard son.

[codyace]

Originally Posted by S13 curtis

WOT. shit pulls hard son.

So on the top end at WOT. Heck my JWT runs 20/21 ont op end, and Enthalpy ones run 23

Now if you were running 19* base and 19 degrees up top, thta would be bally haha.

[AnTi_RiCeR]

i made 433 whp with the .64
19lbs boost
totally rebuilt engine of course though, stage 3 cams, standalone ecu, supporting mods, etc...
responsiveness is great!

[S13 curtis]

dyno sheet please

[jspaeth]

Originally Posted by AnTi_RiCeR

i made 433 whp with the .64
19lbs boost
totally rebuilt engine of course though, stage 3 cams, standalone ecu, supporting mods, etc...
responsiveness is great!

Call BS. On what kind of dyno, with how much correction applied, and did the motor blow up right after?

[S13 curtis]

i wouldnt call bs because it is possiable alot of things become factors like it depends on what fuel because meth, E-85 or race fuel and timing could net you 30 whp or more. depends on the cams, displacement, every one on here is running similar setups thats why u see everyone putting out 350-380whp
try something different and u will get different results. if codyace follows threw with the meth and adds a couple pounds of boost im sure he would net at the least 430-440whp possiably more and he is on a T2 back side, if he had a T3 set up with all of that 450+whp would be possiable. just think outside the box.

[AnTi_RiCeR]

I had the following done:

Full port and pollish, balanced and blueprinted, over bored (don`t remember how much exactly)
Apexi Power FC D-Jetro
Crower Cam Stage 3 (not positive on the lift)
greddy adj. cam gears
JE rods / pistons
upgraded oil sump
greddy oil pan
nismo 740cc injectors
Splitfire ignition
Garrett GT2871R .64 A/R on a t2 flange style
Custom exhaust manifold
3.5" catback with high flow cat
Brian crower valves/springs/retainers

alot more, too much to remember off the top of my head/list.
spent about 13k on rebuilding this motor, the only thing i didn't go with was the 2.2l stroker kit.

Hoping to get more power this summer by maxing out my turbo efficiency at 25psi?

dyno tune was done at autodream in calgary.

i dont have a scanner or i would post my dyno sheet.

I can try to get the dyno sheet uploaded sometime when i find a scanner.

[jspaeth]

Originally Posted by S13 curtis

i wouldnt call bs because it is possiable alot of things become factors like it depends on what fuel because meth, E-85 or race fuel and timing could net you 30 whp or more. depends on the cams, displacement, every one on here is running similar setups thats why u see everyone putting out 350-380whp
try something different and u will get different results. if codyace follows threw with the meth and adds a couple pounds of boost im sure he would net at the least 430-440whp possiably more and he is on a T2 back side, if he had a T3 set up with all of that 450+whp would be possiable. just think outside the box.

Okay, well in that case I see your point. Ethanol or nitrous or anything other than pump gas is no longer comparing apples to apples.

Same thing once you start messing around dramatically with the housings, it's no longer really the same turbo....but anyway, that's a moot point.

Originally Posted by AnTi_RiCeR

I had the following done:

Full port and pollish, balanced and blueprinted, over bored (don`t remember how much exactly)
Apexi Power FC D-Jetro
Crower Cam Stage 3 (not positive on the lift)
greddy adj. cam gears
JE rods / pistons
upgraded oil sump
greddy oil pan
nismo 740cc injectors
Splitfire ignition
Garrett GT2871R .64 A/R on a t2 flange style
Custom exhaust manifold
3.5" catback with high flow cat
Brian crower valves/springs/retainers

alot more, too much to remember off the top of my head/list.
spent about 13k on rebuilding this motor, the only thing i didn't go with was the 2.2l stroker kit.

Hoping to get more power this summer by maxing out my turbo efficiency at 25psi?

dyno tune was done at autodream in calgary.

i dont have a scanner or i would post my dyno sheet.

I can try to get the dyno sheet uploaded sometime when i find a scanner.

Nice, well good luck then!

[codyace]

433, nice man! What fuel and timing were you looking at? That sounds like a damn perfect run if you ask me...take it to the track ever and get a trap speed?

As far as 25 psi, I think you'll just be blowing hot air at that point.

[codyace]

Originally Posted by S13 curtis

if codyace follows threw with the meth and adds a couple pounds of boost im sure he would net at the least 430-440whp possiably more and he is on a T2 back side, if he had a T3 set up with all of that 450+whp would be possiable. just think outside the box.

I reallllllly wanna get to a dyno soon. I'm gonna play with adding a few more (2) psi of boost, and will also experiement with adding 2 more degrees of timing back at 20 psi to see how it works.


375-400 to me is about right on a off the shelf rom tune, 20 psi and pump gas. Really anything more involves race fuel/meth/e85 and some timing/boost.

[mattro]

im in the process of building my engine, looking for the 400 range but idk what cams to get to better assist my turbo, should i just crank the boost or invest in some cams?

reason why im posting in here as opposed to starting a new thread is you guys (for the most part) know your shit, or at least sound like you do.

my setup.

silvia q N/A sr20
all 500 + supporting mods, pump, inj, maf ,blah blah.
stock de cams,
top mount, t67.
JWT ecu.

i was thinking of just sticking with jwt cams. some s3's, for more "low" end umph. since i most likly wont see boost untill 6k

[mattsil80wis]

with a t67 you should look at JWT S4's or HKS 264 step II's

[jspaeth]

Originally Posted by codyace

433, nice man! What fuel and timing were you looking at? That sounds like a damn perfect run if you ask me...take it to the track ever and get a trap speed?

As far as 25 psi, I think you'll just be blowing hot air at that point.

Agreed on the hot air

Originally Posted by codyace

I reallllllly wanna get to a dyno soon. I'm gonna play with adding a few more (2) psi of boost, and will also experiement with adding 2 more degrees of timing back at 20 psi to see how it works.


375-400 to me is about right on a off the shelf rom tune, 20 psi and pump gas. Really anything more involves race fuel/meth/e85 and some timing/boost.

Where do you live in PA? Near Evans? I was up there a few months ago getting tuned.

I am looking to spend some time in the spring tuning my car at a place called Xenocron Tuning which is right on the NJ/NY border near 287....they have a Dyno Dynamics which they will rent out for 120 (first hour) + 80 per hour for 2nd hour and up.

Where are you looking to go?

[codyace]

Originally Posted by jspaeth

Agreed on the hot air

Well, it will make more torque...but thats about it haha.

Originally Posted by jspaeth

Where do you live in PA? Near Evans? I was up there a few months ago getting tuned.

Oddly enough, I live 15 minutes north of Evans TUning

Originally Posted by jspaeth

I am looking to spend some time in the spring tuning my car at a place called Xenocron Tuning which is right on the NJ/NY border near 287....they have a Dyno Dynamics which they will rent out for 120 (first hour) + 80 per hour for 2nd hour and up.

Even wierder, I've been there as well (2 times actually). Chris is a class act.

Originally Posted by jspaeth

Where are you looking to go?

The dyno we hang out at/work/run (I was there today lol) is at
Deihls Paving, in Allentown PA
1712 Hoover Avenue, Allentown, PA‎ - (610) 264-4470‎

[jspaeth]

Originally Posted by codyace

Well, it will make more torque...but thats about it haha.




Oddly enough, I live 15 minutes north of Evans TUning



Even wierder, I've been there as well (2 times actually). Chris is a class act.




The dyno we hang out at/work/run (I was there today lol) is at
Deihls Paving, in Allentown PA
1712 Hoover Avenue, Allentown, PA‎ - (610) 264-4470‎

Hmmm I may have to give that a shot then, too.

Jeff did a good job, but there's only so much you can do in 2 hours.

I'd like to spend much more time and do some steady state tuning to try and optimize the timing and fuel in as much of the map as possible.

Right now, my wideband reads way too rich during full throttle pulls (gets into mid-high 10's) and I showed Steve Shadows my timing map, and he said he doesn;t like it.

So, I have doen a shit ton of reading and would like to get on a loading dyno like a Dyno Dynamics and do cell-by-cell optimization.....

I would be willing to throw you some cash if you could help me....

Do you work with PowerFC at all? I have datalogit.....

What kind of dyno is the one you mentioned above?

[jspaeth]

Just wanted to hear some answers to this.

Max hp on dyno at full boost (19-20 psi) was roughly 370 hp.

Add drivetrain loss of 20% back in, end up at roughly 465 hp at crank.

Now, if you put in a BSFC of 0.65 and use 90% injector duty, and use 62 psi at the rail, an injector calculator suggest almost IDENTICALLY 740 cc injectors.



Reason I say this is that I am hitting 90% duty on 740ccs with 19 psi boost and ~370 whp.


The theoretical calculation says this makes sense, but I read a lot of people's threads where they say 740s SHOULD be good for much more than this....

Are those people full of shit? Are they running higher base fuel pressure and not saying so? Is something sketchy with my numbers (duties higher than they should be?)

Thanks

[codyace]

Originally Posted by jspaeth

I would be willing to throw you some cash if you could help me....

Do you work with PowerFC at all? I have datalogit.....

What kind of dyno is the one you mentioned above?

I don't really have much experience with tuning cars, other than the domestic stuff I've helped with - I'm a much better builder/fabber than the computer kinda guy.

The dyno we use is a Dynojet, so no steady state like Xenocrons DynoDynamics for sure.

Originally Posted by jspaeth

Max hp on dyno at full boost (19-20 psi) was roughly 370 hp.
...
Now, if you put in a BSFC of 0.65 and use 90% injector duty, and use 62 psi at the rail, an injector calculator suggest almost IDENTICALLY 740 cc injectors.
...
Reason I say this is that I am hitting 90% duty on 740ccs with 19 psi boost and ~370 whp.
...
Are those people full of shit? Are they running higher base fuel pressure and not saying so? Is something sketchy with my numbers (duties higher than they should be?)

I'm running 615cc Seimens injectors, and at WOT i'm only at 90 or 91% duty cylce...running 43.5 base fuel pressure (with vacuum off).

Something seems really a mess, or it's simply using to much fuel injector in your tune.


As far as BSFC, I don't follow that shit at all. Seems to 'varrying' for me ya know? Because in regard to S/C cars, it's really off....they suck much more fuel (in bigger power setups) than that the traditional calculators suggest.

[jspaeth]

Originally Posted by codyace

I don't really have much experience with tuning cars, other than the domestic stuff I've helped with - I'm a much better builder/fabber than the computer kinda guy.

The dyno we use is a Dynojet, so no steady state like Xenocrons DynoDynamics for sure.



I'm running 615cc Seimens injectors, and at WOT i'm only at 90 or 91% duty cylce...running 43.5 base fuel pressure (with vacuum off).

Something seems really a mess, or it's simply using to much fuel injector in your tune.


As far as BSFC, I don't follow that shit at all. Seems to 'varrying' for me ya know? Because in regard to S/C cars, it's really off....they suck much more fuel (in bigger power setups) than that the traditional calculators suggest.

See that's what I don't get. Fuck

I mean my FPR works...it's an Aeromotive beefcake unit. If my idle vacuum is 8 psi, then when I pull the vacuum line off the FPR, the fuel pressure goes up by exactly 8 psi.

I have a Marshall liquid-filled gauge under the hood, but no way of seeing fuel pressure from the car.

Just bought a new Walbro to put in, but if the pump is being weak under load, then putting a new healthy pump in will fuck up the tune.

Sure my tune is too rich under WOT (about 10.5-11 AFR), but that's not enough to account for me seeing 90% with 370 whp with 740s and you seeing 90% with 615s at 400+ whp.

Maybe my fuel pump is getting weak? But then that is just fucking awful bc then the whole tune is essentially pointless up top, unless the fuel pump "fails in the same way every time".

Fuck me. Not literally, figuratively.

[codyace]

Originally Posted by jspaeth

If my idle vacuum is 8 psi, then when I pull the vacuum line off the FPR, the fuel pressure goes up by exactly 8 psi.

YOu're only pulling 8 inches at idle? That's half of where it should be...that's another issue in itself if that's the case there...

Originally Posted by jspaeth

Sure my tune is too rich under WOT (about 10.5-11 AFR), but that's not enough to account for me seeing 90% with 370 whp with 740s and you seeing 90% with 615s at 400+ whp.

Maybe my fuel pump is getting weak? But then that is just fucking awful bc then the whole tune is essentially pointless up top, unless the fuel pump "fails in the same way every time".

A weak fuel pump wouldn't dictate higher duty cycle of the injectors though...if anything you'd need more pressure to compensate

[jspaeth]

Originally Posted by codyace

YOu're only pulling 8 inches at idle? That's half of where it should be...that's another issue in itself if that's the case there...



A weak fuel pump wouldn't dictate higher duty cycle of the injectors though...if anything you'd need more pressure to compensate

8 psi!!!!!!!!!!

With stock intake mani and cams, I was pulling roughly -430 mmHg at 1100 RPM at idle, which is roughly 9 psi or so (same as FSM says is correct).

After cams and Greddy intake mani, I idle higher, and their is more overlap...seeing around -8 psi or so (-370 mmHg) at idle at ~1250 RPM.


.....as for the fuel pump statement, I don't agree with you, or, I wasn't clear in what I stated.


If the fuel pump is weak under load WHILE getting tuned, then achieving the proper AFRs is gonna require more duty than most people would use up top.

Hmmmm I am really lost on this....I just don't see how my duties can be that high....they are good injectors....Tomei 740s.

Fuel pump seems okay and FPR seems to work ok, but again, I see people with smaller injectors and same power level (also with 43 psi base fuel p.) with similar duties at high RPM under WOT and similar boost.

[KoukiMonsta]

interesting, mine is much higher. w/ similiar setup

my idle pressure that is

Originally Posted by codyace

YOu're only pulling 8 inches at idle? That's half of where it should be...that's another issue in itself if that's the case there...



A weak fuel pump wouldn't dictate higher duty cycle of the injectors though...if anything you'd need more pressure to compensate

Originally Posted by jspaeth

See that's what I don't get. Fuck

I mean my FPR works...it's an Aeromotive beefcake unit. If my idle vacuum is 8 psi, then when I pull the vacuum line off the FPR, the fuel pressure goes up by exactly 8 psi.

I have a Marshall liquid-filled gauge under the hood, but no way of seeing fuel pressure from the car.

Just bought a new Walbro to put in, but if the pump is being weak under load, then putting a new healthy pump in will fuck up the tune.

Sure my tune is too rich under WOT (about 10.5-11 AFR), but that's not enough to account for me seeing 90% with 370 whp with 740s and you seeing 90% with 615s at 400+ whp.

Maybe my fuel pump is getting weak? But then that is just fucking awful bc then the whole tune is essentially pointless up top, unless the fuel pump "fails in the same way every time".

Fuck me. Not literally, figuratively.

[jspaeth]

Originally Posted by KoukiMonsta

interesting, mine is much higher. w/ similiar setup

my idle pressure that is

Wait, you mean you pull more vacuum?

Stock SR vacuum is roughly 7.5 psi or so.....which is roughly 400 mmHg.

Right now I am seeing like -360 mmHg....but this is presumably due to the higher overlap of the 264/264 cams.

Anyone familiar with Power FC?


When my tuner tuned my car, he put the injector correction at 55% (740ccs).

Technically, they should be 50%, if you were to work off of the base map, since the stock injectors are 370cc.

He just used 55% to richen up the whole map.

Now, I am wondering if that 55% vs. 50% is causing the PowerFC to define Injector Duty differently....i.e. it says 90% duty but it's not really 90% duty.

OR there is the possibility that I am full of shit and something is fucked up.

[codyace]

Originally Posted by jspaeth

8 psi!!!!!!!!!!

With stock intake mani and cams, I was pulling roughly -430 mmHg at 1100 RPM at idle, which is roughly 9 psi or so (same as FSM says is correct).

That's unusally low. Most stock cars I see in the 15-20 range, and most cammed cars are in the 17-13 range.

So as before, I'm really confused as to why you are pulling so little vacuum at idle...especially at 1100 rpm.

Originally Posted by jspaeth

.....as for the fuel pump statement, I don't agree with you, or, I wasn't clear in what I stated.

If the fuel pump is weak under load WHILE getting tuned, then achieving the proper AFRs is gonna require more duty than most people would use up top.

That makes more sense now, but IMO a weak pump would show up in the AFR's as going lean on the top end, and not really pump anymore (I know that the tune could however be setup for more fuel, but I'd think he'd see that on a dyno ya know??)

Originally Posted by jspaeth

Right now I am seeing like -360 mmHg....but this is presumably due to the higher overlap of the 264/264 cams.

Should still be at least 12, if not 14....heck we pulled more vacuum on S5 JWT cams (270 duration, huge N/A cams).

Originally Posted by jspaeth

OR there is the possibility that I am full of shit and something is fucked up.

I wouldn't say you're ull of shit at all...you're going about the problem in the exact manner you should....nothing on your end here. I really hate saying this, but it really seems like this may be in the tune itself. Evans is world class, so i know that in itself is blasphemous for me to say, but it really seems it at this point.

[jspaeth]

Originally Posted by codyace

That's unusally low. Most stock cars I see in the 15-20 range, and most cammed cars are in the 17-13 range.

So as before, I'm really confused as to why you are pulling so little vacuum at idle...especially at 1100 rpm.

That makes more sense now, but IMO a weak pump would show up in the AFR's as going lean on the top end, and not really pump anymore (I know that the tune could however be setup for more fuel, but I'd think he'd see that on a dyno ya know??)


I wouldn't say you're ull of shit at all...you're going about the problem in the exact manner you should....nothing on your end here. I really hate saying this, but it really seems like this may be in the tune itself. Evans is world class, so i know that in itself is blasphemous for me to say, but it really seems it at this point.

1) It seems clear to me that everyone is getting mixed up. Those of you who are saying "15-20" are referring to IN MG, not psi. There is a difference.

If I take my -350 mmHg and divide by 25.4 mm/inch, you get -14 IN HG.

So my vacuum is okay, you guys were just mixing up the units....I was saying -7-8 PSI.

2) Cody, as far as the tune, he did say that it seemed like he was using more fuel than he thought he would have had to.

The reason it is not "leaning out", is because if the pump was also weak during the tune, then he just added as much fuel as necessary while tuning (more than most people need up there?) to get the AFR in check.

So, as long as the pump behaves the same while driving as it did during the tune, the fuel delivery will be the same and the car will be safe.

It is possible (but I DOUBT it) that the fuel pressure is not going all the way up to 62 psi at full boost (43 +18 psi boost), but I really, really doubt this, as it is a very good FPR I am using, and it works PERFECT in the other direction (i.e. when I pull the vacuum line off at idle, the FP goes up by EXACTLY what my boost controller reads as the vacuum pressure).


j