If it's easy to get the air filter off I'd inspect the compressor housing to make sure the blades aren't rubbing. I've had a few turbos go bad on me and they reacted exactly like this. It sounds like your stuff is newer so I wouldn't think the turbo is junk, but it's worth a quick check. When it comes to the electronic side and boost controllers it's goes over my head so I can't help there. Check the wastegate to see if it's got any mechanical issues? That's all I got! Hope it's an easy fix.

 

I do want to check out the turbo because although it only has 2k miles on it, around the time I bought it there was a bunch of guys having problems with theirs.

 

So looks like I still get some compressor surge under like 5k in 3rd gear. Needle stutters a bit after 20 psi. Then after 5k its perfectly still at 25.
Im guessing the engine just can't take that flow rate when low rpm isn't demanding the air. According to hp we hit 47.6 lb/min at full boost

 

are you still running the stock intake manifold?

 

Yes.
If it was a intake restriction issue, the problem should get worse depending on how much air I force, correct?
So considering the issue clears up at 5k, I'm guessing its not restriction related.

I'm guessing I need more air at lower rpms/cams

 

Doesn't quite work like that. Look into reading a compressor map. Typically with non-name brand turbos the compressor wheel is such that it moves the surge line to the right.

 

I have replaced internals with garrett parts as well.
So you don't think it has anything to do with forcing 47lb/min at 4k rpm? The lsj stock head can take that?

Also, since the turbo has been rebuilt, its only the housings that are no name. Would an anti surge housing help

 

Possibly, but only if it is compressor surge. Do you have a gopro?

 

I do not, but i can film the boost gauge to show you.

seeing the jagged curves as it surges in HP logs makes me belive that under 5k it is surging in 3rd.

maf and map are going crazy. then smooth out.
injector duty cycle also goes up

 

Buy an 808 keychain cam for like $10, you'll be surprised at how much they come in handy. They are the size of a key fob. Its what I used to watch my fuel pressure under the hood before I got FP gauge. Cheap alternative to a GoPro if you don't use it much or for anything extreme.

 

oooh pretty neat

 

Just read the compressor map for this turbo. The math checks out, in surge territory until 5200 rpm ughhh

 

anyone dyno'd 6262 with .63 AR to 8000rpm? want to know if it is worth going with .82 AR or not

wanting to spool sooner rather than later but need to have the upper rpms as well

 

full ***** at 4k. till 8k. .63 housing is fine.

basic comparo graph.
http://honda-tech.com/showthread.php?t=2801402

google that ****

 

sounds like the OP of that thread was saying go with the .82 AR but you are correct that it didnt make much diff

 

Rollie aka killass has the 6262 with .82 and it spools pretty late. You gonna be using that N20 to spool?

 

.63 is the way to go, especially on our cars. You won't fall off up top. My friend's both had the .82 on their Evo's and the boost held 42 psi strong to 9k and into the mid 700's whp.

 

So I'll just stay away from 4k in 3rd gearr

 

is the 6262 with .82ar a split t4 housing?

 

You can get the split with T4

 

I would get the split t4 and use a QSV, great bottom end spool and tons of top end

 

For a car that costs a pretty penny to spin above 8.2k, we don't have a lot of top end...

 

Or we just have a bunch of pussies that won't take it past 82

 

9k all day! ......ok no I don't

 

You really can't fault the engine for that, it wasn't engineered or intended to be taken past 7200 and be VE friendly. I'm glad these aren't torqueless rev monsters (aka honduhs) because I think the power curve on the LSJ is extremely smooth and perfect for a daily driver. If you want to make power past 8k you gotta spend serious cash on reworking head ports and valves, and make sure the guy knows what he's doing.