I think it depends a lot on the tune up too. A lot of people try to get a little too aggressive on timing and fuel to make 15 more horsepower...which you probably can't feel anyways at the power level you'll be at. Tune it thoroughly, make sure you get the VE correct even where it won't normally be for boost so that if something changes or causes it to act a little different (weather, boost leak, stuck wastegate, fuel from a different brand/season) the tune isn't suddenly dangerous, and you'll probably be fine.

 

How are the heads coming along?

 

Picked up the heads yesterday. Machinist say they are straight and no reason to surface them (or a valve job). Cleaned them up and swapped the springs for $30. Figured if he was trying to make money he would have surfaced them for $90 and a valve job for another $190.

 

Just an fyi I found over the past few years, GM has some of the most state of the art cnc machine equipment you can buy that they build these motors with. Much better than most local machine shops 40-50+ year old equipment.

Unless you absolutely HAVE to have something fix, I would always say with the machine work GM did. It's much higher quality and tolerances than most shops can even do.

 

Local guys here start pushing water over 15psi on stock parts. So my answer is yes or no depending on intended boost levels.

 

Yeah, Grob builds AWESOME machinery.

 

700 to the tire... upgrade them both.

 

Update...

Been running with LS9 head gaskets and ARP head bolts since the 19th of March on 10 psi without missing a beat. Plenty of low end for towing too.