What is lfx compression

[PlenumBiscuit]

Where should a good compression psi be at for an lfx are they high or low compression motors

Did mine tonight and all pistons were about 155 psi on a warm to hot motor

So this week have disabled fuel flex sensor, check compression and found 1 of the spark plugs were gapped wrong at 0.9 where it should be 1.02?

Anyways the motor is still shuddering up hills...but is not so severe since I put a full tank of premium 95 in it

Next I guess is new ecu? Change trans oil check for shavings, clean cam sensors or?

Could it be knock related?

 

[07GTS]

static is about the 11.5 comp but depends on the valve events as to what the gauge pressure will be but if yours are all the same then its a sign that its prob ok, this is where i mentioned to get someone with a good scan tool or tuner that can log alot of data as this will show u whats happening when u have the issue, they will be able to see if the trans is slipping, loosing pressure or many other things, also if engine is missing or going lean or rich or knocking and much more

 

[uglyoldfatbastard]

Compression should be 150-180 on those engines and anything less than 140 is an issue but of course then comes the question how good is the gauge you have!?! But since they all came in at 155 I would call it good.
I would drain the trans and have a good look to rule that out and then we can take it for a spin up the hill with the computer hooked up and record data and see what is happening.
Let me know..................

 

[PlenumBiscuit]

Compression should be 150-180 on those engines and anything less than 140 is an issue but of course then comes the question how good is the gauge you have!?! But since they all came in at 155 I would call it good.
I would drain the trans and have a good look to rule that out and then we can take it for a spin up the hill with the computer hooked up and record data and see what is happening.
Let me know..................

rippa thats an awesome idea