Pretty self explanatory title...
Just bought an lm7 with 862 heads. Should I keep those or get something else? Plan on going turbo and shooting for 650-700 whp.

 

I ran the 862' and ON3 twin 70's. I went a best of 6.04 in the 1/8th in a 3720lb daily driver. I think those heads work well on the 5.3 with FI.

 

I agree, I made 844 on 22 lbs with a set of untouched 862s they work just fine

 

Awesome. Thanks guys. Just wanted to make sure since I see all these guys running different heads with port jobs and what not. So I wasn't sure. Haha

 

They are working great for me also.

 

What rpm are you guys spinning the oem heads to? I was thinking about buying the Trunion Upgrade kit...worth the cash of even needed? Already dropping in a BTR Spring and Retainer kit in there for good measures.

 

^^^ Good question!! I'm not really concerned about rpm's too much. Would I need to upgrade springs and retainers? Should I just go ajead and do it since I have the motor apart?

 

I up graded to Brian Tooley Springs. I run stock rockers though but I only run to 7k max. No trunion upgrade

 

Sorry for the thread jack OP...I presumed you would also ask similar questions. I did the BTR Spring Retainer Kit because I too wanted to spin to around 7k rpm. Depending on what rpms you will be spinning too and what cam you use, some people have gotten nice results with PAC single springs and retainers. I did the BTR kit because of my goal.