hey guys, I'm new to the forums here and have done some research before posting to not double post so to speak. I still have a few questions in regards to an LM7 build I am working on and was looking for some guidance. First, I have the option between a 99 or a 2000 engine, are there any main differences between the two? I know the GM injector numbers are different, but is that just due to the flow rate or are the sizes and what not physically different. The vehicle that this engine is going in is a 2000 Sierra 1500, so I wanted to stick with the 2000 engine. However the 1999 engine has less miles and is already pulled out and much easier to work on. It had a tag reading "XDJ" on the head and I didn't know if those were good or bad heads, haven't been able to find much on them. This build will consist of a BTR cam, pushrods, and beehive valve springs along with a 76mm turbo. Thanks in advance for any pointers you may have.

 

Don't think there is much if any difference between the 1999 and the 2000 motors. I never heard of that tag on a head before but there should be a # on the head like 706 or 853.

 

Awesome thank you! I will look for that other number. Interesting though, there is a large tag that says XDJ, I'll have to take a picture next time I am down at the shop.

 

I apologize for the misinformation, the tag on the head reads "XJB". Where would I find the numbers you were referring to?

 

The numbers he is referring to are located on the top corners of the head.

 

Here is a pic of a 706 head. See the # on the far right bottom corner.

 

Roger,


Thanks guys. Any one better than the other?