Looks like I lost number 7 piston did a compression test and it read nothing on 7 and its running oil out of the spark plug hole cranking it over with no plug in it....

I have some forged pistons and rods on the way, but how do i fix the lean issue... I did a search and some say its the intake some say its the fuel rails?????

 

Yeh, I have read on here that the intake causes more air to enter the #7 cylinder making it go lean. Others have said it is because the #7 runs hotter do to the fact that there is no crossover in the back for the coolant. Just to be safe you can get a flow matched set if injectors and put the one that flows the most in the #7 cylinder. If it is running lean it will add a tad more fuel which should also help if it runs a little hotter since the extra fuel can cool the cylinder a little.

 

I always thought it was Meth or Alchy that solved the 7 and 8 lean issue?

 

I got some injectors just like that from somebody on here

 

swap to a better intake, get some flow-matched injectors, and if you are concerned about it, have your tuner fatten up the tune just a bit so it doesnt run on the edge

 

Do you have the rear crossover blocked off? It might no totally fix your problem, but it might help to vent those also.

 

Why did they start blocking the back off? Mine has all 4 connected..

 

It is not the intake. Several on ls1tech have reversed the intake is race setups and still loose #7. The problem is the firing order and #7 not being cooled as efficiently as the other cylinders. A slightly better flowing injector in #7 helps. Others have changed the firing order and had good success.

 

i could have sworn i saw on ls1tech where they determined it was a combination of the stock intake and the water jackets/cooling for the rear cylinders. might be remembering something else.

 

no one has relay answered the issue with proof positive info. LOTS of ideas on what causes it... some say intake, some say coolent, some say fuel rails, some say timing..... But like others have said. tune a bit fat...