Crate vortec 350, 390hp question

[L31MaxExpress]

I guess it’s a preference thing. The L31 is inherently better down low, but after years of working out of 6.0s, I’ve really grown to appreciate them for what they are. I’ve always been a BBC guy, so I’m all about the down low. But I’ve found that a 6.0 with 4.10s is more than adequate for my needs, which are greater than most who are just driving them back and forth to work everyday. I ride mine hard and put them up wet since my first one in 2003, and they’ve always been loyal. I even did the Duramax thing for awhile and came back. Far more expensive up front, they cost at least twice as much to operate, and are of no practical use to justify the costs to anyone not towing >15k. But that’s a whole different argument.

And if the trans went out tomorrow I could pull the engine, throw rings and bearings in it, put it in a street car and throw 20lbs of boost at it all day long, and go buy a new truck dirt cheap. The versatility is unmatched. If the heads are cracked, you can find a good set of 799s for $300 all day long. You won’t find 062s for under $700 because good used ones simply don’t exist. Unless you buy cheap eBay remans and send your cores back. You want to run a cam in a 6.0 and not pay $150 for springs and retainers that may or may not work or try to hack up your valve guide bosses with a die grinder, go ahead. Those are the kinds of things that deter people from even bothering with the L31. I have a lot of respect small block builds because nobody bothers with them anymore. For me, it just doesn’t make sense. You’ll make much more power per dollar spent with a big block build in NA applications, and with an LS based iron block in boosted applications.

Up until Lloyd ported my Amazon Assault racing heads I had less than $800 in them and was running .578 lift on both sides with a non self aligning 1.7 roller rocker.

I am also a big block guy which is why I have 2 vehicles powered by cammed 8.1s. Head/Cammed 6.0L do not touch them. 450+ HP at 5,000 rpm and 550 tq @ 4,000. More than 400 tq @ 1,000 rpm.If an 8.1 fit in my Express van without cutting the firewall and floor for the bigger doghouse opening it would have one to.

 

[m002922]

Not trying to hijack the thread, but since I'm in a similar position to the OP and everyone is offering thoughts on engine combos, I'll chime in with related questions.

1st - the OP said he was trying to use the stock intake - there's been discussion of the etec 170s, etc. - I assume those won't work with the stock spider system because of the mating of the typical gen-1 head vs. the vortec. Am I remembering that right?

Regarding towing. I reached out to Pace about he motor the OP was talking about and asked about towing - the response was to buy the Chevy 383 crate. Nice thought - also $2k more . . . which I would prefer not spend. Pace didn't really offer any opinion of the OP's motor, only stating the 383 would be better.

2nd - Anyone have any thoughts on the ability to tow 7k lbs. (which I believe the stock truck was rated at with the 5.7 and 3.73s) with a stock L31 4 bolt block, stock intake, but HT383 cam (headers, exhaust, 411, tow tune, better torque convertor for towing, heavy duty radiator . . . )?

In thinking about it I realized the transmission may be more of the issue, and 4l80 would solve the 4l60 inherent weakness and 1-2 gear spacing / durability issue (and since my trans is on borrowed time, the 4l80 is an option), and then you could go even deeper rear gears if you wanted to make it more capable.

Anyone towing with the the 350/HT383 and a 4l60e that can offer thoughts of towing with that near the truck's original rated limit? That would give me a benchmark for consideration. I live in Florida - so I'm not climbing mountains.

 

[c1500deathtrap]

LS engines also often burn 1 qt every 1,500 miles or less and GM considered that normal.

There was a TSB that fixed alot of the oil burning issues. It replaced the old valve cover with a revised version. I believe it was to fix the baffle for the PCV.