GT2871 USERS. SR motor

[Seraphim38]

with luck I am finally heading to Portland tomorrow for custom tuning on a brand new Apexi Power FC D-Jetro setup with new boost controller, new MAP and AIT sensors and harness, fabricated intercooler piping with no couplers mid pipe, new Tial BOV to replace my old Greddy RS and aftermarket billet throttle body. Combined with my new SR20DET built top to bottom, external wastegate GT2871R and everything else I am getting a bit anxious.

[Zgirl93]

Hey guys, I'm semi new to the auto world and I am trying to self educate myself. Anybody interested in helpin me out?

[cured13]

Originally Posted by Zgirl93

Hey guys, I'm semi new to the auto world and I am trying to self educate myself. Anybody interested in helpin me out?

1. get a good paying job

[Mesarina]

Went to the dyno last week.. car has

z32 maf
walbro 255
apexi pfc
nismo 740cc
tomei fpr
freddy intake manifold
stock exhaust manifold
gt2871r .64
3" complete exhaust

262,74whp/212,67rwtq @8psi
287,19whp/241,45rwtq @14psi
317,89whp/257rwtq @18psi
294,15whp y 268,22rwtq!!! @24psi but let off because of knock...

[R@ddy]

Kinda hard to believe there was just a 25 whp and 29TQ difference between 8psi and 14psi

[LuckyX2]

Originally Posted by Mesarina

262,74whp/212,67rwtq @8psi
287,19whp/241,45rwtq @14psi
317,89whp/257rwtq @18psi
294,15whp y 268,22rwtq!!! @24psi but let off because of knock...

Something is wrong with your setup or the dyno. I made 299ftlbs of torque out of an S15 turbo at 17psi and you're only making 257ftlbs at 18psi on a 2871? It was also almost 20 degrees hotter the day I dynoed mine...

[Mesarina]

Originally Posted by s13_kidd

Kinda hard to believe there was just a 25 whp and 29TQ difference between 8psi and 14psi

can it be because i didn't touch the timing map between 8 and 14psi?

Originally Posted by LuckyX2

Something is wrong with your setup or the dyno. I made 299ftlbs of torque out of an S15 turbo at 17psi and you're only making 257ftlbs at 18psi on a 2871? It was also almost 20 degrees hotter the day I dynoed mine...

What may be wrong? not to much timing? Im running about 8degrees at the top to be on the safe side, more than 10 and I get knock readings near 60...

[di-devol]

Shouldn't it be something like 19 up top? I'm no tuner, but I thought that was close to what it should be around. I could be completely wrong though.

[Conrad 2NR]

Sure the timing on the PFC is properly synced?

[LuckyX2]

Originally Posted by di-devol

Shouldn't it be something like 19 up top? I'm no tuner, but I thought that was close to what it should be around. I could be completely wrong though.

Yeah when I tuned my old setup with the S15 turbo I followed Enthalpy's guidelines on Freshalloy and that put me around 18 degrees or so at full boost (17-18psi). That was with 93 octane gas. The rule of thumb I used was 3/4 of a degree decrease for every pound of boost just btw.

It should not be knocking at only 8 degrees. Are you absolutely sure it was knock?

Also, it could be your AFR's. They look lean on that graph. You should be around 13 from 0-5psi and 11.5-12 for anything higher than that. Aside from the one run that dipped down to 11.5, your AFR's are all around 12.5-13 under boost which is not good.

[LuckyX2]

Found the link to that timing guide:

</title> <link rel="shortcut icon" href=/images/"favicon.ico" > <link rel="icon" type="image/gif" href=/images/"animated_favicon1.gif" > <script type="text/javascript"> </script> <script type="text/javascript" src="http://www.freshalloy.com/clientscr

And here's my basemap that I built from that:


As you can see, I have 18 degrees at 17psi.



Keeping everything linear and smooth is key as you can see in the 3D view.

Start with something similar to mine but retard the whole graph a few degrees. Then on a dyno, bump up the whole graph a degree at a time until you knock or stop making power then back it off a degree or two. At that point you're 90% there and just fine tuning is left. Ideally, you'd have a load bearing dyno to fine tune the cells in small groups from that point and extract the last bit of power/drive-ability.

This is the same map that did 293whp and 299ftlbs on an S15 turbo with poncams spiking to 17psi and falling off to 14psi by redline on a 95F day. Obviously, get your AFR's right first before you mess with the timing.

Hope that helps!

[Mesarina]

Originally Posted by Conrad 2NR

Sure the timing on the PFC is properly synced?

synced as in putting 15 degrees from 500-1500rpms on the table and making sure the cas ignition timing with a timing gun is the same? I did that.

Originally Posted by di-devol

Shouldn't it be something like 19 up top? I'm no tuner, but I thought that was close to what it should be around. I could be completely wrong though.

I read in this thread that 10-12 timing with 18psi is about right

Originally Posted by LuckyX2

Yeah when I tuned my old setup with the S15 turbo I followed Enthalpy's guidelines on Freshalloy and that put me around 18 degrees or so at full boost (17-18psi). That was with 93 octane gas. The rule of thumb I used was 3/4 of a degree decrease for every pound of boost just btw.

It should not be knocking at only 8 degrees. Are you absolutely sure it was knock?

Also, it could be your AFR's. They look lean on that graph. You should be around 13 from 0-5psi and 11.5-12 for anything higher than that. Aside from the one run that dipped down to 11.5, your AFR's are all around 12.5-13 under boost which is not good.

Originally Posted by LuckyX2

Found the link to that timing guide:

</title> <link rel="shortcut icon" href=/images/"favicon.ico" > <link rel="icon" type="image/gif" href=/images/"animated_favicon1.gif" > <script type="text/javascript"> </script> <script type="text/javascript" src="http://www.freshalloy.com/clientscr

And here's my basemap that I built from that:


As you can see, I have 18 degrees at 17psi.



Keeping everything linear and smooth is key as you can see in the 3D view.

Start with something similar to mine but retard the whole graph a few degrees. Then on a dyno, bump up the whole graph a degree at a time until you knock or stop making power then back it off a degree or two. At that point you're 90% there and just fine tuning is left. Ideally, you'd have a load bearing dyno to fine tune the cells in small groups from that point and extract the last bit of power/drive-ability.

This is the same map that did 293whp and 299ftlbs on an S15 turbo with poncams spiking to 17psi and falling off to 14psi by redline on a 95F day. Obviously, get your AFR's right first before you mess with the timing.

Hope that helps!

Thanks for that usefull post, My afr is different on my innovate wideband, stays between 11.5:1-12.2:1 at wot, I do trust more my wideband than the one on the dyno, the wideband used in this dyno may be wrong, it sucks, but it's the only dyno we have here in Guatemala, but im going to put all the table richer at the track to see if this helps, I hope so, best thing I like now is that it's safe, been using it as a daily without any problems, next mod are BC 264's, already have the spring kit and cams, i'm just waiting to get some studs and headgasket to do the job..

[codyace]

With the power levels these things make I'd keep the AFR moddest and have the top end timing in the 20/21 range...timing is more addictive than boost though, so be careful

[Mesarina]

Also it doesn't know at 8 degress at 18psi, but it does if I use 10-12.. I don't have datalogit, but i'll copy my table and post it here, Thanks

[LuckyX2]

Originally Posted by codyace

With the power levels these things make I'd keep the AFR moddest and have the top end timing in the 20/21 range...timing is more addictive than boost though, so be careful

What psi do you consider "top end"? If I remember correctly, I wound up advancing it about 3-4 degrees on top of my base map before power fell off so my final timing was about 20 degrees at 17psi. That would be in accordance with what you're saying; however, top end boost is not the same for everyone. I wouldn't suggest people run 20/21 degrees at something like the 24psi Mesarina was shooting for. At least not on pump gas that is.

[di-devol]

I don't know why i keep having trouble with this setup, but the turbo seems to be letting go. First installed made boost at 4200rpms with the .86 housing. Went drifting and thought i blew the turbo gasket, went to change it and it looks great. I was making boost in the 5k range. I swapped to a .64 housing and boost is 4500, with really slow spool. Bov is blowing oil out, and some tasty shaft play. Buddy is really helping me out with a gt2876, that will work for now until i can top mount it.

[codyace]

Originally Posted by di-devol

I don't know why i keep having trouble with this setup, but the turbo seems to be letting go. First installed made boost at 4200rpms with the .86 housing. Went drifting and thought i blew the turbo gasket, went to change it and it looks great. I was making boost in the 5k range. I swapped to a .64 housing and boost is 4500, with really slow spool. Bov is blowing oil out, and some tasty shaft play. Buddy is really helping me out with a gt2876, that will work for now until i can top mount it.

Poor oil flow to the turbo itself? I've seen on more than one occasion where a faulty feed line (granted on a big rig) being the culprit of turbo death.

[di-devol]

Originally Posted by codyace

Poor oil flow to the turbo itself? I've seen on more than one occasion where a faulty feed line (granted on a big rig) being the culprit of turbo death.

Nah, turbo has had a rough life. I know it came originally from a Pro-am car that made it to FD. I got it from the person who got it from that dude. Compressor blades were chewed up when I got it. had some shaft play, but it was cheap. I can make 10psi by 4k lol, no leaks, car idles great(finally), just slow as hell spooling.

[inopsey]

Originally Posted by LuckyX2

Found the link to that timing guide:

</title> <link rel="shortcut icon" href=/images/"favicon.ico" > <link rel="icon" type="image/gif" href=/images/"animated_favicon1.gif" > <script type="text/javascript"> </script> <script type="text/javascript" src="http://www.freshalloy.com/clientscr

And here's my basemap that I built from that:


As you can see, I have 18 degrees at 17psi.



Keeping everything linear and smooth is key as you can see in the 3D view.

Start with something similar to mine but retard the whole graph a few degrees. Then on a dyno, bump up the whole graph a degree at a time until you knock or stop making power then back it off a degree or two. At that point you're 90% there and just fine tuning is left. Ideally, you'd have a load bearing dyno to fine tune the cells in small groups from that point and extract the last bit of power/drive-ability.

This is the same map that did 293whp and 299ftlbs on an S15 turbo with poncams spiking to 17psi and falling off to 14psi by redline on a 95F day. Obviously, get your AFR's right first before you mess with the timing.

Hope that helps!

what did you use to make sure running all that timing wasnt causing knock wot? you use alot more timing everywhere than i do, and my map is basically the pfc base map minus a few degrees in a few places; pfc runs an aggressive base map iirc.

[LuckyX2]

Originally Posted by inopsey

what did you use to make sure running all that timing wasnt causing knock wot? you use alot more timing everywhere than i do, and my map is basically the pfc base map minus a few degrees in a few places; pfc runs an aggressive base map iirc.

Why would you take away timing from a base map? The idea behind a base map is that it's conservative and timing is supposed to be added to it.

And honestly, I just used my ears... Sounded nice and steady up top and the dyno curve was smooth, no jagged lines that would have shown up if it was knocking.

I rented a dyno for two hours (but spent an hour of that time fixing problems...) at Import Intelligence in West Chester and the owner there was nice enough to hang out for a bit with me and he didn't hear any knocking either. He also asked to see my maps when I was done and he seemed surprised what I did with it in only an hour of dyno time. He said my timing was close to how he would have done it, had I payed him to tune it.

EDIT:
Here's another post I found with an SR20 map. He's running 18 degrees at 18psi too:
http://www.toymods.org.au/forums/sho...=1#post1175381

Also, you'll notice that my timing only changes with load when under boost, not RPM too (except for a precautionary retardation in the low RPM boost area that it should never get to). This was the design of the basemap only but there is more power waiting to be had in the high RPM boosted areas with some more timing.
Timing can and should go up as RPM goes up because the piston is moving faster which means less time for combustion, which means you should start the combustion earlier with more advanced spark.

[tabasco122]

2871 going up for sale soon, im parting out my setup, for no real reason other than i need to make a responsible choice and get rid of the money pit

[Seraphim38]

This could probably be its own build thread, but anyway…

Story: After a complete rebuild of a new SR20DET setup bottom to top, finally I have gotten it to be tuned right and stable. After 1,200 break in miles on various Enthalpy tunes, I bought new Apexi Power FC D-Jetro system with new MAP, AIT sensors and new harness, and took it to Portland Speed Industries for a custom map. They do the tuning for the vast majority of pro-am and pro drivers in the NW drifting circuit. Aside from some small technical details of getting it ready to tune, the baseline map came out pretty quick. The battery went dead from leaving it sitting with the fans running, and somehow the alternator got fried from jump starting it with the polarity of the cables reversed, so the dyno was run with the electrical system at 12.0 volts. When it finally got tuned enough to full boost runs, it was heat soaked and pushed near identical hp at 18 psi and 20 psi.

Final result: 341 rwhp and 280 tq. As seen in the dyno video below, it spins up very fast. The tuner indicated that if we let it cool down and run it again he would get another 20hp if not more, but I indicated I was looking for a reliable, responsive, powerful and safe configuration for daily driving. Timing under boost is at 16 degrees. I wasn’t looking to push out some ridiculously high number if it compromises the durability of the car. As it turns out, the map had 40 degrees of timing throughout the low to mid rpm off throttle positions and the car detonated a lot in daily driving. Even with octane booster (waste of money), I had to drop ignition timing to the 29-30 degree range in order to avoid detonation.

Impressions: I love the Power FC. I have experience remapping fuel injection systems and recognize its short comings, but for what it is I am very happy about its usability and effectiveness. The car pulls very hard beyond 5K rpm, but I was hoping for more response between 4k and 5k (full boost doesn’t hit until 5k). The billet throttle body and custom fabricated intercooler piping is absolutely gorgeous but I have no idea how much hp it is worth. I intend on sticking with this setup for a while and enjoying it before doing anything else under the hood (there isn’t really anything left to do except swapping to a top mount 3071 or LSx).

Eye candy:




Dyno video:
SR20DET GT2871R External Wastegate dyno - YouTube



Wiseco 9:1 pistons, 86.5mm
Eagle rods
Wiseco pistons 9:1 compression
ACL race bearings
ARP head studs
Ported head
BC264 12.0mm lift cams
JWT cam gears
Greddy valve springs
Greddy/Trust rocker arm stoppers
BC titanium valve spring retainers
Apexi 1.1mm metal head gasket
New OEM timing set
New OEM oil pump
Garrett GT2871R .73AR T25-EWG-44 housing
Tial 44mm v-band external wastegate, 1.1 Bar, with custom dump tube to atmosphere (loud)
Greddy tubular exhaust manifold with 4 layers of ceramic coating
All turbo hardware is stainless studs with copper lock nuts and nord lock washers
Apexi Power FC D-Jetro standalone with MAP sensor and integrated Greddy boost controller selenoid
7 layer exhaust gasket
Circuit Sports braided turbo oil & coolant lines
Splitfire coil packs
Greddy/trust turbo elbow
Greddy down pipe
Invidia 3” full exhaust with Magnaflow 3” spun metallic catalytic converter extra 3” Magnaflow race muffler and single 3 inch in, dual 2.5 inch out Magnaflow muffler
Custom fabricated stainless steel 2.5” intercooler piping with HPS silicone couplers and T-bolt clamps
Era-1 billet throttle body
Port-matched stock SR20DET S13 intake manifold
HKS top feed fuel rail with all Aeroquip push lock -AN lines & fittings
Injector Dynamics 1000cc top feed high impedance fuel injectors
Aeromotive Fuel Pressure Regulator and -8 AN push lock lines
Aeromotive -10 micron billet fuel filter
Aeromotive 340lph Stealth fuel pump with relay
Tial Q 50mm blow off valve
Circuit Sports oil block adapter
10AN Aeroquip oil lines to Offenhauser remote PH43A oil filter mount
Permacool 160 degree oil thermostat
CX Racing 13 row oil cooler
Greddy oil pan (6.5 quarts total engine oil capacity)
Stance water pump pulley
Stance water neck spacer
Billet power steering reservoir
Flex-A-Lite power steering oil cooler
OEM Nissan water pump
Samco silicone hoses
OEM Nissan thermostat
Koyo race radiator
Blitz radiator cap
Circuit Sports coolant reservoir
Dual electric Altima fans (DIF controller yet to be installed)
A/C removed
Blue powdercoated valve cover
Tomei oil filler cap
Rebuilt alternator
RPS Max stage 3 clutch
Nissan OEM clutch slave cylinder with braided stainless line
B&M quick shifter
Nismo rubber shift knob
1 piece aluminum lightened driveshaft
Nismo motor mounts

[BlackZenkiS14]

Are any of you guys running Meth/Water with your 2871's? If so, what AFR are you running with the meth/water at WOT? More looking for info/advice from 300ishwhp SR guys who are on the safe side.


I am running a 7 water/meth nozzle, at 17psi, and 11.7-12.1 AFR through the RPM band. Does that sound about right?

[Seraphim38]

I ran a Snow Performance kit on a supercharged mustang I used to have, but I can't say whether it was worth it or not.

Locally one fo the pro-am drifters runs it on his drift car, though he's also running a top mount turbo setup dynoed at like 500rwhp.

While meth injection can help for adding octane and to cool the intake charge, if your tune relies on it and a flow issue develops (or you run out of fluid) you can blow your motor. I have seen more than a couple of STI engines that blew because their water meth system failed or ran out of juice.

IMO race gas is always a better option than a water meth system, even if it is a pump/race gas mix. And octane boosters are a waste of time. If you do use race gas, remember that leaded gas will kill your O2 sensors on no time; you have to use unleaded race gas if you are using O2 sensors in your engine management system.

[EsChassisLove]

Heading to the dyno at 11.

Hoping for over 330whp with stock cams.

[huffandpuff00]

@ 18lbs I put down 330whp w/ stock internals...just give it a couple extra lbs and you should be more that 330whp!

[gotta240]

Originally Posted by EsChassisLove

Heading to the dyno at 11.

Hoping for over 330whp with stock cams.

1. What dyno you going to?

2. Why does it say you have S3 cams in your profile? Did something happen with them?

[EsChassisLove]

Don't have time to install them

I deploy in 6 days didn't feel like dealing with it. Just wanna tune it as it is, and enjoy the last few days with her.

They are just hanging out in storage until I get bak. Good call I need to take those off the sig.

[EsChassisLove]

Oh and it's also still on a PFC D-Jetro w/commander and AVCR.

[gotta240]

well.....how'd it do????? And what dyno?!?! I'm still looking for a good pfc tuner near san diego or even LA