Engine guys please help!


So probably not the tune but data may help diagnose....There is no EGT or EGR, the (Caspers) fuel pressure sensor is off calibration so it reads low (maybe 10-15 psi I have to dig out my cal data) I did verify pump/regulator performance and replaced pump anyway since it was 20 years old. LS1 3.5" MAF with translator, AEM wideband. MPH is off also since I haver 28" tires.

Thank you.

ok guys sorry for the delay here. After several unsuccessful attempts at getting the DI measurements, I've decided to take a shot at this and see what your thoughts are. Ignore the DI in the first pic. Here are a couple of pics of pushrods at TDC on overlap stroke. To me they seem very even, not off by more than 0.100 as they would be if cam was 1 tooth retarded. I've tried to keep the pic as even as possible. I've placed a 6" steel scale accross the top of the rocker pedestal for better reference. Thank you!

You need to measure pushrod height on overlap. DI is on spring, why?
Take a look at the #1 pedestal. There is a ruler laying across. You can see the pushrods the motor is at overlap TDC. Their height looks even to me. The DI is actually just suspended in the background not really on the retainer as it appears… that’s why I said to ignore. Lol
I only see one pic on one retainer, not multiple pics.... TIMINATOR
There are 2 pics one without DI in background and one with. Both are supposed to be showing #1 pushrod height at overlap TDC against straight edge of ruler on pedestal behind.
Have either/both sets been bench verified as GTG?
A "spare set"... what's the story on them?
One plug looks like it's being drowned.
I verified that FP wasn’t dropping once turned off since I suspected a leaker. Then I pulled the set I bought from a friend that switched to E85. Bought a low mile set with TT6.1 from someone here for my T but hadn’t installed. I cleaned them and once installed i checked that set for fuel pressure drop. I didn’t notice any change in how it ran last year when swapped.
I sent the first set to grant Farmer and he cleaned and flowed and certified them as GTG. They are not in the car right now. The set I cleaned are in there.
Did you do a compression or leakdown test when the engine was together BEFORE the bearing issue? If not, the current ones only show what you have, not a meaningful comparison.
Compression and leakdown, if it is as even as yours is, has nothing to do with the unbalanced mixture issue you are currently experiencing. Let's assume for now that the long block, and cam timing are fine, and figure out what is causing the unbalanced fueling issue.
Since our normal, non high zoot engines have only one O2 sensor, it can only read the AVERAGE of what all of the 6 cylinders are doing.
What can affect this unbalance?
Individual injector filters
Crappy injector(s)
Restrictions (junk or corrosion) in the fuel rail.
Bad injector (leaking or under fueling)
Corrosion at the injector power plug(s).
High resistance or intermittent connection in injector individual wiring harness
Regulator diaphragm going bad, therefor changing/ fluctuating fuel pressure
Partially or intermittently plugged fuel return line (could be in tank, connection hose at the tank, or in pump/sending assy.
Fuel pump intermittent power wire or relay/ ground.
Bad/intermittent power or ground(s) in injector harness/plug in.
I would: connect a fuel pressure gauge at the test fitting on the rail. Is it consistent? Moves around?
Remove the fuel rail, blow it out, and put it in carb dip over nite or longer. Blow it out again.
Disconnect the return line, blow it out, (disconnect from tank) and or run a length of hose in a bucket and see if it has a steady return flow.
Have you replaced the fuel filter recently?
Blow out the fuel lines individually from tank to filter, and filter to regulator.
Read the pump voltage at the TANK while running or key on/engine off.
Rig up a "T" in the return line off of the fuel rail, pressure there should be minimal.
Any electrical intermittent to the pump or grounding, pressure or return line partial restrictions, or regulator/ filter intermittent restrictions will cause the computer to "chase its tail."
Start with the easy ones first.
Pack a lunch, and Excedrine, you're gonna need it!
Keep us posted.
You cleaned the injectors or an injector rebuilder, tester did it by running cleaner under pressure then measuring flow??
For no more than GOOD injectors cost, buy NEW ones! GOOD ONES!
And dip clean the fuel rail while it's off.
Like the man said, quit dicking around!
I obviously missed the part about the "cleaned" injectors. But, this thread may help others, and that's why we are here.
Individual injector filters
Crappy injector(s)
Restrictions (junk or corrosion) in the fuel rail.
Bad injector (leaking or under fueling)
This is an example of the filter baskets being FUBAR.
These 2 pics are the same set, with and without the filter baskets being screwed up.
The customer chased that tune for a while!


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How did you clean them?
I used something like this with a can of carb cleaner to clean the second set prior to install.
injector tester
The first set was then removed and sent to Grant Farmer and he did his thing measuring flow using cleaning fluid, etc. There was essentially no difference in the flow before and after. Both sets are Siemens 60# from precision.
I didn't find any difference in the way the car ran (rich chunky idle) or in fuel pressure holding (not leaking down rapidly)...but that was last year and I was working on something else and not that focused on this problem at the time.