Lean Misfires at 2700-2800 rpm

[badass3000]

I dont know if I mentioned it or not, but my heads where rebuilt from (4) valve strikes also.
We may have something here.
rockers are so much easier to change than heads.
BTW HG are $30-35 a peice.

[badass3000]

alright, just pulled my rockers!
I didnt even put on shoes
I didnt notice anything wrong with them.
Still want to throw in known goods while im in there.
Jake, can I borrow some rockers?

[badass3000]

whats most likely to get damaged from valves hitting pistons?
besides piston, valves, and mabey guides.

I dont see how a lifter or spring could be damaged.
rockers/rollers could be possible.
cams and cam caps might take some damage.
retainers and locks dont sound logical.

[DoctorDex]

Originally Posted by badass3000

alright, just pulled my rockers!
I didnt notice anything wrong with them.

So they all spin freely and there is no flat spot on any of the needle bearings inside?

[DoctorDex]

Do you have a set of "known good" heads for a swap?

[badass3000]

I havent tested ALL of my rockers, only the suspected bad ones.
my known good heads are my stockers.
havent seen them in a while, they did have worn seals, but all that means is a little smoke.
but I have only one set of cams/rockers/lifters

[J-Ville VR-4]

Originally Posted by badass3000

alright, just pulled my rockers!
I didnt even put on shoes
I didnt notice anything wrong with them.
Still want to throw in known goods while im in there.
Jake, can I borrow some rockers?

If you let me borrow an engine stand and help me pull my engine (easy, theres no front end whatsoever on my car and everything on the engine is already removed) during my spring break in 2 weeks you can use anything from my car that you want for testing

I might not even need the stand either, I bet Dan has one that he's not using, but if you arent using yours, that would be a little more convenient.

[Gamerse]

Subscribed. I've had smmilar issues since I've bought my car. At one point I considered the timing belt, but I replaced it for lack of maintence records, and no change. Since then I've been lazy/living with it, focusing on other areas, like repairing every electronic component in one way or the other, minus the ECU, some other sucker has already replaced that.
My car is all stock minus the main cat/test pipe, free boost mod. Looking forward to your results.


P.S.

2) If I cold start the car and then rev it up in neutral, it revs smoothly through the entire rpm range. Once the car gets warm, ie. coolant temp of > 120 - 130* F it starts to miss. On the other hand, if I try and drive the car right away when it is still cold, it'll still miss in the 2500 - 2900 rpm range. In fact it misses horribly when I drive it when it is cold. At times it will literally fall on its face once it gets to 2600 rpm. I think this has to do with the ECU adding extra fuel while the car is warming up and this effectively masks the problem.

That describes my car to the letter, it does run better when warm though.

[markoverclock]

Originally Posted by badass3000

does your rear valve cover still make noises?
mine does too, and theres no reason mine should, there super clean, freshly built, and have 99 liters

same here, fresh motor too. i have a "jump tack" to in the logs. i do believe mine might be a little different. i have jumped my t-belt alteast 2 times, one with an oem t-belt tensioner and one with a aftermarket one. so i now since then have put in a couple washers on the tensioner rod that comes out of the tensioner so that it cant colaspe back in. so far no t-belt loosing. but i still have the 2-3k miss. i have to really richen mine up to run ok but it boggs down because its so rich and cant keep driveing like that , dont want to spin a bearing, gas mileage .

i still have to do a compression check and a leakdown check maybe ill do that tomaroo after work. ill also be getting a set of used heads that will be gone throgh for a new install. also will be using arp head bolts. i just used the factory ones, "i know they are torque to yeild " i was a cheap bastard on that . but iether way ill have the heads redone. but that wont happen till i sell this 19t setup. so i can do everything at once. my heads only have 5-6k on them as the rest of my setup. i also didnt have this problem when i was stock before i blew the motor up due to overboosting and not monitoring anything.
so if you guys want to do head gaskets i think im going with the copper ones this time "and an o-ring job on the heads?"

[DoctorDex]

Unless you are planning on doing it anyways, you should wait to swap your heads until after I've used the scope on my car. The scope is going to cost me $45/hr, so I'm going to have to try and be as time efficient as possible. Which waveforms does everyone want me to check? I'm planning on checking the injectors and the CAS. Is there anything else I should be checking?