S14 sr20det lag?? S15 t28..... ???!?!?!?!?

[1slowsilvia]

Ok so I have a S15 T28 (yes it is a S15 T28 I pulled it from a spec r in person)

its mostly a stock SR.... I'm also rocking a stock down pipe :eek2: sucks I know but had to use it as some butt fucker sold me a garbage down pipe that dont fit period. I have FMIC kit test pipe and apexi gt spec... thats about it for mods.

Here is the issue. When I floor the car I don't get any "real" power until EXACTLY 4k rpm. also even by brake boosting at 3500 rpms my boost will hit and HOLD 4psi. then when I hit 4k rpm ON THE BUTTON its almost like fucking Vtec boost goes to 10 psi and I start hauling ass....

Could this be because I am on the stock ECU? its the kouki "NA" as this is a kouki s14 SR20. this makes zero sense as to why my boost will not go past 4psi until I hit 4k rpm and then i get SURGE in power and start putting power down. Also I have a speed limiter @ EXACTLY 200 kph I have the US cluster so my top speed shows 120 mph but at 200 kph it hit it and thats it.
ALSO my idle sucks dick.... it likes to idle then miss and then idle them miss a few times then idle up again.... does this over and over.

I tried getting new spark plugs NGK BKR7E gapped them to .30 and it idled LIKE COMPLETE SHIT pulled them out and put old ones back in adjusted gap on old plugs to .30 as they were .40 and idled like it use to just misses at idle and I feel power loss / miss in upper RPM. ALSO my rev limiter is 7k RPM on the nose WTF? Every SR20 I have owned had 7600 RPM Rev lmiti.... why 7k on S14 SR???
any idea on wtf is going on?

Also I am running S15 480cc injectors without tune.

I am pulling them and putting the stock S14 370cc injectors in tomorrow.

but seriously makes no sense about the vtec 4k rpm shit. I know my motor has VTC but WHAT THE FUCK?


TLDR?

boost limit till 4k rpm goes from 4psi to 10 psi even if i brake boost at 3500 rpm will limit boost until 4k rpm exactly.

speed cut at 200 kph.

7K rpm rev limit. power loss in upper rpm / breaking up.

Stock Ecu Stock kouki S14 SR20 480cc s15 injectors no tune.

[1slowsilvia]

Anyone got any ideas?

[EDacIouSX]

Ok so I have a S15 T28 (yes it is a S15 T28 I pulled it from a spec r in person)

Also I am running S15 480cc injectors without tune.

Stock Ecu Stock kouki S14 SR20 480cc s15 injectors no tune.

There's your answer............ yes s14 sr is 7k rpm from factory, it's not the same sr as the s13 and s15. I do not know why the s15 sr is 7400 rpm red line while the other s13 SRs are 7500 i believe, not 7600. could be 7600 though, no sure but s14 is the lowest red line of 13/14/15.

[Croustibat]

No tune, but bigger injectors ... your car is just overfuelling like hell. Get a tune and dont drive that car until you do ...

I am curious to know why you insist on T28 from an S15 spec R ? They are the same as every other T28. Only some late JDM S14 and early S15 specR had a ball bearing unit. Other than that BB core, they just have the same flow.

anyway ... get a tune. Yes it is going to cost you money, no you cant keep driving like that, no you cant get away with just an SAFC, no you cant do it yourself either (if you knew how to, you would not have asked)

[1slowsilvia]

Ok I installed stock 370s doesn't run rich any more....

The car still doesn't have full boost till 4k rpm...

Idle is still shit Boggs bad dunno why

[1slowsilvia]

anyone have any idea why my SR limits boost and power until 4k rpm on the nose then full power... cause its like 70% power then 4k rpm and full power and boost goes from 5psi to 10 psi. all this happens at exactly 4k rpm.

[bussitcustoms]

I am curious to know why you insist on T28 from an S15 spec R ? They are the same as every other T28. Only some late JDM S14 and early S15 specR had a ball bearing unit. Other than that BB core, they just have the same flow.


This is not correct.

[1slowsilvia]

This is not correct.

yeah kid deff has his info wrong.... still hoping someone can shed some light on the problem with boost im having.

[Rb26kouki]

my car is doing the same -_- no fucken torque!!

my friends 1.6 D16 single cam Honda Engine is more responsive then my SR i know this cant be right.

i have a s14 black top SR
NOT SURE WHICH ONE
(WC ECU IN BLACK)

[cotbu]

Get tuned, make some logs and post videos.
If you are cruising at 2500rpm, then go full throttle(wot) by 3400rpm, your 2560r, gt28r s15 turbo turbo should be fully spooled and full boost( 7-17psi) easy. if you are easing into the throttle and notice a breakup or hesitation get it tuned, or at least check codes.

The turbo runs off exhaust, what could hinder it's performance Hmmmmm. restrictive exhaust is one, Remove the restriction. then test. boost leaks and fuel delivery, timing oh yeah and user just to name a few.
my friends 1.6 D16 single cam Honda Engine is more responsive then my SR i know this cant be right.
In every honda scene there's at least 4 people whom dabble in tuning and will encourage anyone to go see one of those tuners.
240's owner will drive their shit, half broken and well...... yeah!

[Rb26kouki]

Motor was 100% until
Today
Installed Greddy 3in down pipe
3in test pipe & apexi evo n1 exhaust
Greddy front mount intercooler

Want to get a good elbow && tomei is making a new one won't be released till end of April?

[dorkidori_s13]

1) fix all your boost leaks
2) get an adjustable FPR and set it to 35-40psi
3) buy a boost controller/adjustable wastegate (HKS makes an awesome wastegate) and set it to stock boost (12psi NOT 7!!!)
4) FIX ALL YOUR BOOST LEAKS!!!

i was having the same exact issue up until this weekend. no matter what i did, nothing until 4k. car ran like buttsauce under 4k RPMs. come to find out i had a massive boost leak at the turbo intake (where the intake bolts to the turbo). i reangled the stupid thing (cut + weld), installed a new coupler + new tbolt clamps. also, i redid ALL of my couplers on the hot side of my turbo with brand spanking new tbolt clamps. i set my HKS wastegate actuator to 12psi (STOCK BOOST!!! NOT 7 PSI) and turned my FPR up a smidge to 40psi (from 35)....the goddamn car has NEVER run better!!! no spits, no stalls, no jumps, no rough idle...it purrs like a kitten and pulls like hell to redline after 3200rpms!!! (and yes im running a stock MAFS and ECU)

so yeah, check EVERYTHING!!! if need be, get new couplers, get new tbolt clamps, double check your torque on EVERYTHING PIPING RELATED!!! oh, and an adjustable FPR and wastegate help worlds too (if youre running a stock FPR, youre pushing 60+PSI in fuel pressure if youre running a walbro...WAAAAY too high)

[Rb26kouki]

I just purchased
All new mishimoto couplers w/ t-bolt clamps
Car has a nismo Fpr don't know what is set at I believe stock I need to get a gauge to make sure
I also have a hks actuator (uninstalled)
How do I set it at 12psi?

Also just replaced all turbo manifold gaskets.

[dorkidori_s13]

you need a boost gauge to set proper boost. each turn (on the new HKS wastegates) is roughly 1 PSI once you have it in proper vacuum resistance.

throw that NISMO FPR in the garbage and buy something with a gauge. i would HIGHLY recommend a unit made by SARD or Aeromotive.

[Rb26kouki]

Alright thanks for the info
I will post up when I have done that see if my sr has better response

[1slowsilvia]

Awesome thanks for the information!

Right now I am running a stock down pipe (I know it sucks) but as soon as I get paid at first of the month I'll be buying a O2 housing / down pipe combo off ebay for 150.

does running a shit intake to the turbo cause it to run like ass cause I am running that autozone acordian style pipe and I'm sure its random air to come into the intake. I'll get the stock one and put it on there see if it fixes the problem.

I'll also look into to getting a nice FPR soon!

[motorhed]

Silvia, turbo motors need a ton of air so yes go to stock air intake for now that could be ur problem.

[Croustibat]

This is not correct.

So much arguments and info in your post. Coming from someone who likes calling others "typical douche", that was not really surprising :picardfp:

There are 3 references for a T28bb on RWD SR :

some JDM S14 : 14411-69F00
Eu S14a (late S14 model) : 1411-82F01
JDM S15 specR : 14411-91F00

and 1 last for the GTIR:
4411-54C00

Not all of S14 JDM, EU S14a and S15 spec R had a BB turbo either.

Every other model has a journal bearing turbo, with serial 75F00. No S15 outside Japan had a bb turbo from stock, and nissan replaced the BB turbos for journal bearings on S15 after a while, because it was too costy for them to produce and maintain.

If you think that info is wrong, feel free to ask nissan themselves, and go shit in someone elses boots.


@OP > you got a boost leak, and maybe your CAS is not set correctly. Check your turbo temperature (visually, dont touch it) after pushing it, if it is red you clearly are running bad timing and will be killing it shortly.

You need to make sure that FPR is set to 3bar; also make sure it is genuine. If it is, dont change it, that would be wasted money.

Forget ebay 30$ jobbies, get a good FPR like an aeromotive one from a known seller.

Also, make sure your current actuator is not blocked ... if it is stuck a bit open, it will prevent boost from building up soon, but will also prevent boost regulation.

As for your intake, as long as there is no leak between the MAF and the turbo, it does not matter. These engines use a MAF. Mass AirFlow sensor. They are no alphaN system, changing the filter for a less restrictive one wont harm anything (it wont bog down the engine anyway). Make sure there is no leak, as MAF systems DO bog down when there are leaks.

[headup240]

Dude my s14sr is doing the same shit(NA code ECU too) and I even hooked up consult and all of my sensors are reading correctly with perfect AFR. Shit is slow as hell. Passed boost leak test too.

[djcobra]

Maybe look at your internal wastegate, the rod could be off where it moves the flap (c-clip). Most people tend to over look this when installing a turbo.

Steve.

[1slowsilvia]

Just wanted to clear up that I do have the Dual Ball Bearing turbo....

I did all the research and pulled this turbo off a 2000 Silvia Spec R...

http://i433.photobucket.com/albums/qq58/1slowsilvia/58819_10152591307510486_1463233075_n_zps0ce6d6df.j pg

I'm going to undo EVERY coupler and tighten them alllll back down and make 100% sure that there is NO leaks at all. then I will undo my nigger rigging of the MAFS intake piping. I'll also check my CAS to make sure its set to 100% stock.

At idle it idles then holds steady.... then boggs then boggs then will rev back up after about 2 mins of this it will bogg VERY hard then just shut off.

[Croustibat]

Do you have a BOV ? If you do, block / remove it and try again. Most of them leak at idle when there is a high vacuum, that could be part of the problem. They usually dont leak when vacuum is not that high though, but you can try.

[1slowsilvia]

Do you have a BOV ? If you do, block / remove it and try again. Most of them leak at idle when there is a high vacuum, that could be part of the problem. They usually dont leak when vacuum is not that high though, but you can try.

I do have a leaking piece of shit Greddy Type S

[headup240]

I might know what it is. This is a common problem with s14 srs. See if your vtc solenoid is working properly. You will be able to hear it click with the car in 1st gear. Push the clutch in and listen for the click at 1100 rpms. VTC creates most of s14 sr mid range torque. 1050-5700 rpm.

[e5s4y]

my turbo does the same exact thing. same spec r turbo. sard fpr, aftermarket o2 housing back exhaust, stock manifolds, fmic, etc. and yep, almost exactly 4k rpms too. iv done boost leak tests before, but i wanna do another one soon. i wish i knew someone with a smoke machine.
redtop sr, stock ecu, stock injectors at ENTIRELY too high duty cycle (lol), stock block and hg.

[e5s4y]

Maybe one of the knowledgable members on here can chime in on this? Croustibat, codyace, pureturbos, etc?
Still pretty curious about this

[steve shadows]

Did you check your timing?

[e5s4y]

Did you check your timing?

Last time I checked, it was as close as I could get to 13* via the consult port and datascan program

[e5s4y]

Timing is 13*, fuel pressure is a hair over 3 bar at idle with vacuum

[Croustibat]

Last time I checked, it was as close as I could get to 13* via the consult port and datascan program

consult is useless, it tells you 13 because it is supposed to be 13. Your engine does not know how to check this, so it assumes it is always 13. Check with a timing light.

Timing is 13*, fuel pressure is a hair over 3 bar at idle with vacuum

What do you call "at idle with vacuum" ? If you have -0.7bar at the intake manifold, your fuel pressure should be 2.3bar. The difference "fuel pressure -intake pressure " should always be equal to 3 bar (yes, that means when you are boosting 1bar, you have 4bar fuel pressure - or should have)

[e5s4y]

With vacuum line from the manifold connected, at idle (cold start, vac at -540ish mmhg) fuel pressure is at 42ish psi. Timing confirmed with timing light also

[Croustibat]

Your fuel pressure is set too high. Unplug the vacuum line from the intake and cap the fitting so there is no leak, then set your fuel pressure to 45psi (with the hose disconnected)

It still does not explain why you got no torque though.

You might have a cracked / loose wastegate flapper, but checking it is a pain.

Thing is, we are on the internet. It is already hard to check an engine problem when it is right in front of you, and it is even harder when we cant have that.

Start by putting that FPR at 45psi, and then show it to a tuner that knows these engines. It may not be free of course.

[e5s4y]

fwiw, this is my dyno chart from today. .8bar. stock ecu, stock injectors, fmic, 3" exhaust, cant tell you what my afr's were bc i bottomed out hard and developed an exhaust leak, but before that it wasnt above 11.8 full boost.
http://i305.photobucket.com/albums/nn235/andrewhuffman/chavesdyno_zpsff70ea76.png

[bussitcustoms]

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