SE not doing so hot..

hey guys, my 88 SE isn't doing as well performance wise as it should. there is this horrible lag from idle to about 3000 rpm. I've done a fair amount of stuff, none of which makes it get any better. Here's what ive done:
-Replaced Plugs
-Replaced Wires
-Replaced Cap & rotor
-Replaced some vaccuum lines (2)
-replaced clutch
-Ka24E TB
-took off airbox, & replaced w/ HKS style air cleaner
-removed AC system, nose to firewall
-2.25"/2.5" Exhaust (cat-back)
-Checked Timing (at 20 BDTC right now!)
-Sea-foam'd the engine (an internal cleaner, works nicely!)

I can't figure out What is wrong! (don't get me wrong, i get 250 miles to a tank!)it just won't GO! i ran with a 2002-03 Neon SXT, and we pushed up to 125, and ran outta road...he SMOKED me from 0-60, but i slowly crawled closer as we neared 125...but i KNOW for a fact, my car is capable of being faster..but its just not hitting it, do you guys have any idea what could be wrong??

run the ecu and see if it is throwing codes also what grade gas do you use?

My VG's no rocket below 2500 or so either, but I don't really expect it to be. I've got a 2.5" exhaust, Flowmaster muffler, and a cone filter, all of which improve top-end response at the cost of a little low-end grunt. That's the main reason I haven't done a KA24 TB yet, I'm not sure I want to remove anymore airflow restrictions through the engine, and risk losing any more low-end.

When you say horrible lag, is it sputtering and hesitating, or what is it doing? Gotta have a little more info to be helpful.

code 55..all is good code!

as far lag..i mean, i put it down and i wait...its like a HUGE turbo..just waiting and waiting..it slowly increases rpms until about 2500, then it GOES like whoa, sorta...its still held back some..but it moves nonetheless..

Sounds like what happened with my car after the ECU went out. Check compression on all your cylinders.

My buddies VG powered Maxima is the same way...it might just be a character trait...:|

would a set of 555cc injectors help? (don't tell me what i know: they don't exist. the way i see it, wee have the identical injector setup when compared to the z32. just different wiring. I'll tinker with that over the winter!)

Check compression on all your cylinders.

how do i do this? (ive been told stick your finger in the plug hole, and see how it feels...w/e!)

You need a compression gauge. It screws in in place of the plug. It's probably gonna be best to find a freind who has one.

would a set of 555cc injectors help? (don't tell me what i know: they don't exist. the way i see it, wee have the identical injector setup when compared to the z32. just different wiring. I'll tinker with that over the winter!)

Heck no! I put 555cc injectors in my Z32 to handle the 600hp it will be pushing. The S12 has absolutely no need for that large of an injector. Also, the Z32 injectors are a completely different design from the S12. They are a side feed injector as opposed the to S12 top feed. Not to mention that because the Z32 uses the rare side feed injector, they cost a fortune.

As for being slow below 2500rpm, does this include first gear? My S12 isn't really very quick below 2500rpm either, that's why I keep it above that. LOL

My SE and Z has been doing this for a while, I still can't track it down...

However I recently read somewhere (here or Z forums...cant remember) that it might be the cat? O2 sensor?

Did this start "all of a sudden?" or was it gradually over time?

Mine is worn out and pulls like a tractor below 3000.

well on the S12 it felt gradual (but don't hold me to that, it's been a while)...on the Z, it happened right after a pit stop during a routine drive home...

gradual..I have a new cat, and the o2 sensor is only 2 years old..(god knows it prob broke just to put me in debt!)

I really think its just running LEAN. its getting all the air it can handle, and then some, and just needs fuel..So, is there any type of Injector that will be an upgrade from stock, but not overkill? (it has to fit, but i can modify the wiring!)

There is no need to upgrade your injectors. If you really think you need more fuel, you can get an adjustable fuel pressure regulator. However, if you're really not getting enough fuel, it's because there is a problem somewhere. You need to find the problem, rather than mask it.

I agree. But also if it's a fuel problem, it sounds more like too much fuel than anything.

too much fuel(rich)..exhaust normal to cool temps..not enough (lean) exhaust REALLY F'kin hot..is that right? my exhaust ticks for like 20 mins after i shut it down..(the ticking is the metal shrinking back)

granted, this isnt my base for comparison..but i was told this once..seeing if its right.