1J Boost q's

[Yotaholic]

Hi all !! I've just completed a 1J swap in my 82 MKII and i've been trying to set up my Greddy Profec B spec 2 controller . It's hooked up correctly ive rechecked several times . I set the warning for 13psi and the limiter at 20% and the set at 0 ( stock boost ) . My goals are to have a reliable 300hp range and not to exceed 13 psi in hopes of keeping my twins for a while. Well all that turned to shit when I got back this morning from a little spirited ride . I checked the peak boost and it reads 19.7 :aigo: .. OMG i'm going to blow my shit up !!!! So right away i'm thinkin stock ecu , stock injectors , map sensor ... I did feel a stumble comming out of 3rd once while heavy on the gas so I assumed that was probably the rev limiter but maybe it was fuel cut anyway the damn Profec should have done it's friggan job and kept me under 13 regardless .. I'm not sure what to do next and i'm hoping you guys can help. This is new tech for me so flame if you must but help if you can . Cheers

 

[honestabe]

Bad wastegates maybe?

 

[Bigzavs]

one of the local 1J guys was having the same problem recently with his Profec B, with it turned off to just run the wastegate (7# spring) he was doin 14 and hitting fuel cut. ill ask him to see what it turned out to be

 

[OneJoeZee]

Hi all !! I've just completed a 1J swap in my 82 MKII and i've been trying to set up my Greddy Profec B spec 2 controller . It's hooked up correctly ive rechecked several times . I set the warning for 13psi and the limiter at 20% and the set at 0 ( stock boost ) . My goals are to have a reliable 300hp range and not to exceed 13 psi in hopes of keeping my twins for a while. Well all that turned to shit when I got back this morning from a little spirited ride . I checked the peak boost and it reads 19.3 :aigo: .. OMG i'm going to blow my shit up !!!! So right away i'm thinkin stock ecu , stock injectors , map sensor ... I did feel a stumble comming out of 3rd once while heavy on the gas so I assumed that was probably the rev limiter but maybe it was fuel cut anyway the damn Profec should have done it's friggan job and kept me under 13 regardless .. I'm not sure what to do next and i'm hoping you guys can help. This is new tech for me so flame if you must but help if you can . Cheers

Ok... well,

1. Running more than 13psi is not going to blow up your turbos (I wish people would stop believing that bullshit. It's getting really old)

2. Turn the boost controller completely OFF and see if you are able to hit stock boost normally. You should have done this first if you hadn't already.

3. Are you sure you have routed your hoses correctly? Tee both compressors together, then to the solenoid. Tee both wastegates together then to the other port on the solenoid.

4. Are you sure you are using the correct ports? Read the manual and make sure you connected to the ports that are for internal WG and not external.

5. Do you have an aftermarket ECU? You should have hit fuel cut before 19psi happened.

6. I'm pretty sure the manual has a troubleshooting section. Refer to it and you should be able to figure out where your problem is.

HTH. If you were hitting stock boost before installing the boost controller without problems, there's only a few places your boosting problem can be now.

 

[honestabe]

I'm running almost 14 PSi right now and have no problems. I wouldn't recommend going any higher than that though on the stock twins.

Adam

 

[OneJoeZee]

And why not?

 

[7Mboost]

All I hear about Profec B's is bad, spike, can't hold boost.

 

[OneJoeZee]

They're not that hard to use. It's just those that use them don't bother to follow the directions in the manual, then they wanna say how much the thing sucks. This isn't a shot at the thread start, just an observation.

I've helped a few people that had NFI what they were doing with there's. After I explained it, it worked great for them. I've used it before and it was fine.

Profec isn't even that complicated in relation to some of the other EBCs that are more expensive and have more features and gadgets.

 

[Yotaholic]

Thanks for the quick replys !!

O.K. lets see if I can answer some questions

1. i. know the Aussie guys have been putting out 20+ for years with stock turbos :icon_bigg I'm just paranoid and trying to take it very easy on them I only have a light show a/f guage and no dyno within 7hrs drive so I have to keep it down until I can get a wideband and safc and maybe a gtech or something for reference as I don't see getting to a dyno this year .

2.My first few runs were with the controller off ....16.0 psi peak steady at 15psi

3. Yep all the lines look correct according to the maunel

4. line connected to NO port for actuator type

5. Stock ECU !! Thats what confuses me I should have hit fuel cut.. It's hard to say what was done in Japan to it but it appears to be stock. I have no tach and no speedo so I can't say if the cuts are operational or not and I didn't hit 180kph well at least I don't think I did , so I can't say if thats working either ... LOL!!!

6. Trouble shoot section gave me some things to check . Setting gain and set boost are giving me doubts so I set the boost at 0 ( stock ) and gain at 2 for a small increment to start from . They mention boost spike may occur if the gain is set too low and boost will continue to rise at higher rpm's so thats sounds like whats going on so i'll raise the gain but it doesn't explain why the warning didn't kick in at 13 ..hmmm I don't know :nono:

Thanks for any advise guys i'm learning as I go.

 

[annoyingrob]

All I hear about Profec B's is bad, spike, can't hold boost.

NOT TRUE.

That's just because people don't bother to learn how to program them. A properly set up profec B will work fine.

 

[OneJoeZee]

So the car is boosting stock with the head unit off?

I'm not sure how you have your settings but do this,

Turn everything down to zero. then turn up the set boost where you want it. Then set your gain value. Too little gain gain and your boost will fall off at high RPM. Too much gain and you'll spike. Then move on to the start boost. This function controls the wastegate. You can actually hear the solenoid when it starts clicking. That's the solenoid starting to open the wastegate. Higher start boost will keep the wastegate closed longer promting quicker spool but you cannot set the start boost too close to the set boost. If the start boost is too close to the set boost, you will have spiking issues.

Let's say you have set boost at .9bar. If your start boost was at .9bar, you would have the wastegate opening up at .9bar and you would surely overshoot your target set boost. Follow?

Do you have a boost gauge? You should really be doing this with a boost gauge. You can read the numbers on the profec but the digital increasing numbers don't give a very good sense of boost characteristics. You can see that alot better with a normal analog gauge.

 

[Wills7MGTE]

HAHAHA You'd think a mk2 with a 1jz would be fast as hell stock swap setup LOL
nice car man I love mk2's too

 

[OneJoeZee]

It's hard to tell what's going on in the video. I can hear the part where you said it's stumbling but I don't if that's just maybe the spark being blown out, detonation, or a fuel cut where it shouldn't be... The video quality is kinda low.

 

[Yotaholic]

I tried what you suggested and noted the changes Thanks Joe. yes the quality is shit but it's just to show when i'm getting the stumble and get an idea of how it's sounding along the way.
Yes with the unit off im holding at 15 psi. but peaked to 16.

next attempt

set boost..25%
gain.........15
start or set gain....2 psi
warning 11.psi
limiter ......20%

holds at @10 psi on the mech guage and no fuel cut seems good

hi setting

50%
15
2
15
30%

rises to @15+ psi and spiked to 24.3 at the stumble ( fuel cut or what ) OMG im fucking my ride !!

 

[7Mboost]

NOT TRUE.

That's just because people don't bother to learn how to program them. A properly set up profec B will work fine.

I'm just saying everyone I've ever heard said it sucked, one had a turbo kit installed on his car professionally, never touched the boost and threw a rod through the block, to find out he spiked to 17 psi.

 

[OneJoeZee]

Wait... You said you were hitting 15 with the unit off? And then you gave your next set of settings with the unit on to net you 10psi?

That cannot not happen. The boost controller can't turn the boost down lower than the base WG setting.

I'm a little confused.

It's hard to diagnosis exactly what's happening without being there but I'd say leave it alone if you're not exactly sure how it's work.

You don't want to blow it up learning how this thing works. Especially if you're not getting any fuel cut when you should be. (Ask me, I know. I did it.)

 

[Yotaholic]

Yes i'm a little confused myself . Maybe I turned it back on before I left and didn't take notice with all the excitment . Makes more sense so i'll make another attempt with it off tomorrow . Your right I should seek help but im in Nfld and there just isn't anybody to ask . Therfore i'm doing it the hard way once again . This really is a PITA and probably not worth the risk with my power goals . Maybe take it out is my safest option and I really expected it to save me grief not cause it.

 

[Ric]

I think your boost gauge is off.

PS, I'm with Joe. If one more person says you'll blow the twins going over 14psi... I'm tired of that false info.

 

[odomd]

With everything stock what is stock 1j boost cut / fuel cut? I put on a manual boost controller but any thing above 14 psi the car violently surges. It is still an auto for now does anyone know how to get around this?

 

[Ric]

^
The best way? A Blitz/SARD/etc... Reflashed ECU.

The "other" way? A Fuel Cut Defenser.