sr20det lag, full boost @ 4k RPM

[bl3ujay07]

Originally Posted by garbury

dude, bad timing can mess up vacuum a bunch too. I'm going with your timing is off. Check cam/chain alignment, and restab the cas according to the fsm. The timing should be right then, and you should be running fine. Use a timing light for minute adjustments.

I took car to shop AGAIN for him to look at and he adjusted it just a tab. He said timing IS right, but I’ll try n double check myself.

Originally Posted by steve shadows

About 99% of "Specialty shops" especially when it comes to Nissans are full of shit.

Originally Posted by steve shadows

I know one locally in the of industry area that is more full of shit than shit itself and is featured in magazines all the time as the TOP nissan shop

so much BS out there

I have noticed most assembly shops don't know jack shit about proper tuning and diagnosis, and most dyno shops are not the best at assembly.

For example at my location Mike does assembly and I just do tuning ..

He doesn’t do dyno. He is credible, been fixing the engine for me and my brother for 3 years now and has been a Nissan Toyota mechanics for 15 years. Yeah yeah…”if he knows so much and is credible, why cant he fix it?” I honestly don’t know. He does his own builds and fixes engines from. Go ahead and bash me if you guys think not. I trust him as my mechanic.

Originally Posted by ross.cottrill

yeah it definately sounds like a timing issue to me.count the links to be sure!

Can you inform me on this please?

[slider2828]

Man lets just stop doing multi quotes in one thread, its annoying and hard to follow....

1. Are you using a wideband to monitor your AFR?

2. Do you have a log so we can all see your AFR's

3. Did you tune your car after the cams?

4. What computer are you using?

5. What MAFS, Injectors, and Pump are you using....

[bl3ujay07]

^^^ lol. yes sir.

1. No sir, no wideband at the moment.
2. No wideband so no log.
3. Car was not tuned after cams.
4. Just a J4 ecu. repinned by my mechanic. No other electronic to tune and no boost gauge.
5. Using stock sr maf and injectors, and a walbro fp

[lazysk8er2]

what sort of gauges do you have that can provide info on the car...wideband is def needed and boost...try and find out how much vac you got at idle

[bl3ujay07]

I have a faze boost gauge (which seems pretty accurate when i switched wastgate actuator). idle is at like 10ish to 11. I'll try and get a wideband soon. Should just look for rich area.

[bl3ujay07]

Alright, after doing massive research, i checked my knock and sensor. It was loose, very loose. It came off right when i grabbed the wire. Found out there was not a cliip to hold the plug to the sensor so i made one out of paper clips. Had the starter off, so i installed it back on and started the car. Vac went to 14 instead of betwwen 10-12. Reved it a bit, and it seemed to respond better.

Then i took it out for a test drive. Still lagging a lot and i know its running rich bc it smells a lot like there is too much gasoline. So i have the negative terminal on battery disconneted for the night. Will try again tomorrow and see what happens.

Also, when checking a j4 ecu, is it the same as any other ecu, i.e. turning the diagnostic screw (???) one time counter clock wise and turn car on without starting??? Can someone help confirm this?

[singlecamslam]

yeah theres a screw at the ecu, turn it clockwise, than back again. As for your RPM dropping all the way down, that could be because of your BOV or your IACV, mine does it too. By the way i know that shop speed of sound, and i dont really trust Phil. Just my opinion though.

[bl3ujay07]

^^^ bad experience? So far, i've had good experiences with him. We've been going to him for a while so he has been giving us some hook up price. Also, sometimes he come to my house to take a look at my car too so, so far so good.

Only "bad" time is when i took my car in and he said its how a sr is suppose to run, but its not because its lagging. He doesnt know or doesnt think there is anything wrong with the car.

[djcobra]

Guy, get a tune!

you've put in decent parts in the valvetrain and still runing stock ecu, and stock turbo... Your whole damn map is way off. I suggest you don't drive the poor SR and start investing in some other parts to make full use of the cams etc... ie, Power FC, thats a start, then get a tune/dyno time.

Have you double checked your vaccum lines? are they routed correctly? Your BOV could be opening too early, there are so many factors.

And don't give me any bullshit that you don't need a tune when you install cams/valve springs/turbo/injectors bleh bleh... anyways, thats a whole different matter.

Here's a reference guide (which i found on here; search)

Quick reference of Turbo and Cams to choose.
T25...Stock, 256/256
T28...Stock, 256/256, 256/264
GT28RS....256/256, 256/264, 264/264
GT2871R .64.....256/264, 264/264
GT2871R .86.....264/264, 264/272, 272/272
GT3071R .63.....264/264, 264/272
GT30R.....264/272
GT35R.....272/272

"Im sure this will bring in some kind of debate. These are the setups i would consider though.
Lowest Cam profiles being for low end response for drifting and highest profiles being for max power for drag racing."

exactly what he said ^^^^^

good luck..

Steve.

[bl3ujay07]

^^^ i know and i want to get it tuned, but not enough money right now. hoping to get a power fc or emanagement soon so i can get it tuned.

[djgrasman]

FINALLY FIXED MY PROBLEM

sorry about posting about my similar problem on your post
but....
i finally found out that it all came down to a leaky injector!!!
damn it really gave me a headache!!!!
then i had replaced it and it all kinda.....went away...
now i have to go back and re-adjust all my sensors to run normally with all four cylinders instead of just three.

hope this helps anyone out there if they have a similar/same problem

[bl3ujay07]

did you replace all your injectors? Also, anyone in norcal willing to help? I am thinking its something to do with injectors also because it sems like my car is running really rich. either that, my knock sensor or mybe harness.

Someone near stockton, ca can help me try and figure mines out. Maybe let me switch things with them to see if it improves and see what the problem is. Just a suggestion if anyone is wiling to help. Also willing to pay a bit too.

[djgrasman]

i had replaced just one
injector number 4
or in other words the last cylinder
the reason why i only replaced one is bc i didnt have the money nor the amount of injectors to replace all of them
but listen if your car is running really rich and is being really crappy i would suggest replacing/checking and swapping injectos to see if it changes how your car runs
the reason your car could be running rich is do to the fact that injectors can get stuck open or end up going and anytime the car is on they just dump massive amounts of fuel "bad injector"
(or multiple injectors)
what is funny is that through the time i had an idle problem no one i had talked to or read up on had said n e thing about injectors to me.
this was a kind of found it out by trial and error
hope this help you out =)

[ninelives17]

hi i know i'm new here but i promise i have searched for an answer to this post, my car is doing this exact same thing, dead till 4000 rpms. does anyone know what finally fixed this guys problem?

[bl3ujay07]

^^^Mine was timing issue. Off by one tooth. make sure you take off valve cover to double check and not just with a timing gun. Hope this helps

[ninelives17]

finally fixed mine. maf was bad, not throwing any codes though. bought a/f gauge and noticed it was running lean. if anyone else has this problem you might want to check it out.

[blkkouki]

Glad to hear you got your porblem fixed. Phil swapped and did the work on my car while I was deployed to Afghanistan.. He does awesome work and he knows his shyt. I even drove my car back to Louisiana from Sacramento. We still stay in contact and he gives me suggestions and calls just to make sure the car is good. So far the car has perfromed flawlessly. Not to mention he gave me an awesome price

[Om1kron]

it's either a boost leak, it's leaking out of your bov, or you have a hole in your intercooler core.

I have the same issue. and I have a stock SR20DET Redtop, idles smooth at 1k, if I baby the car under 4 k no problems... if I get on it I get lag or hiccups on power until 4k. If I rev it drop it at 4k and make sure it stays above 4k it runs like a champ and I can smell oil.

Like a burning smell...

I'm obviously getting blowby as well.

What is your catch can set up like, are you running one? I am not. I need to have some pipes fabbed for that and am waiting on an s13/14 hybrid cover. Also I need to get new injector spacers and o-rings just to make sure it's not a fuel leak on the injector end.

I mean obviously don't know why I am asking you if you have a dude at a shop doing all of your work so us giving you advice is pointless until your mechanic figures it out.

Otherwise every tuning nut on the site will just circle jerk everyone elses theories as we have seen in the first 2 pages.

[slider2828]

If you are getting blowby at 4k, have you done a compression test? There is no way you can be pressuring the crank case that much to get blowby.... There just isn't enough presure to do that except bad rings.... definitely get it checked....

[Charsiu]

I have the similar problem, it feels like big turbo doesn't want to spool until 4000rpm
And it hit boost at 4k rpm and it boost hard, should I check my timing too?

after all my idle is a bit rough and unstable.

I just finish my swap few days ago.

[slider2828]

Check your timing....

[spooled240]

cam timing will greatly affect turbo spool. When I dropped my ka-t in my exhaust cam was a tooth advances and I spooled 5 psi in nuetral lmao

[240sx-pat]

Guys I got a quick question my SR seems to be lacking power. I'm think it's because I've got a leak somewhere and the main place right now is from the downpipe to the testpipe I can feel air coming from it when it put my hand near it.


Could this be the cause of my slow ass SR? I mean my boost gage is showing that it's at 7lbs however I'm not feeling shit.

[cotbu]

Guys I got a quick question my SR seems to be lacking power. I'm think it's because I've got a leak somewhere and the main place right now is from the downpipe to the testpipe I can feel air coming from it when it put my hand near it.


Could this be the cause of my slow ass SR? I mean my boost gage is showing that it's at 7lbs however I'm not feeling shit.

Fix it, but No! Your sr is slow for other reasons! The test pipe and down pipe are after the turbo, so why would you think a leak there has anything to do with why your sr is "slow"! Just FYI 7psi ain't shit and people claiming 205hp while pushing it from the t25 are stupid. push 11psi and see if, you still feel the same way!

[patsS14]

check your cam angle sensor

[idahotuner]

yeah sounds like your a tooth of on one of your cams, i have 264 cams on my car and it idles smooth at 900 rpm with 96# injectors,

pull your valve cover off,
and check cam timing to crank,
and then reset cas, - make sure your not 180 degrees off
make boost tester,
use an air compressor, and pressurize your whole intercooler system through the turbo and listen for leaks, they will be obvious, i have a buddy watch my boost gauge and i pressurize mine up to 30 psi.

[e5s4y]

Originally Posted by djgrasman

hey whats goin on.....i seem to find myself having a similar problem....its weird sumtimes when i hit the gas it doesnt pick up at all.....i hear the turbo spool but no power, also my AEM wideband reads -.- nothing....now when that happens i will lift off the gas a little and it will pick up speed and read an average reading of 14 throught 15 A/F.....wtf is wrong hear? boost/exhaust leak at a specific pressure?

please gimmie sum ideas of what this could be......

this is how mine feels sometimes too. boost gauge reads full boost, but then at 4k-ish, its like a kick in the ass. wideband shows everything good tho. the lifting the pedal a little does increase the acceleration too. still good enough to go sliding around tho, haha
s15 spec-r- t28

[idahotuner]

IDAHOTUNERS SR FIRST START UP - YouTube

this is how it will sound with your cams off a tooth while idling, vacuum will be less then normal, it close enough to idle, and rev up just slower, i never even attempted to drive it when it sounded like this, i new something was wrong and double checked everything,
here is once i fixed it
Idahotuner SR start up RUNNING GREAT - YouTube notice the sound difference, doesn't sound like a big cammed car any more

[idahotuner]

so cam timing

[ghoti]

Just posting for future reference but when you guys say Cam Timing it's when you replace the cams?
To my understanding when being a tooth off on the CAS your car won't start.