Ok please help I wanna convert my orginal 70 396 350Hp to 396 375Hp
Here is the reason for the upgrade.Motor is worn out taps etc.
My friend gave me a 396/375 NOS crank and matching 11.1 forged pistions what cam should I use for this upgrade?I have the orginal cast intake with quadrajet.

***Also I found a LS6 today in a garage with build sheet non matching #'s . I offered 4500.00 please pray that he calls me back tommorow.

Allen, welcome aboard:waving:

Are you looking to have your motor produce 375hp, or make it look like an L78?

For the former, a good rebuild with a new cam and some head work will get you 375hp ( I'm assuming here that you're keeping exhaust manifolds, if you switch to headers, that will help out ).

As far as " making " an L78, 11:1 is correct, rectangular port heads, 4 bolt block, high rise aluminum intake, Holley carb and no doubt a few other things I've overlooked. The 4 bolt block is not necessarily needed, as a well prepped 2 bolt block can withstand alot of abuse, and can also be fitted with 4 bolt caps if you desire.

Lots of possibilities, tell us more about your car and what your plans are for it.

1970 L78/LS6 motors used a low rise,aluminum intake casting # 3963569
Rebuild your current motor with a nice street cam (something in the 224-230ish @ .050 duration, .500-.550 lift)
and buy one of those intakes. And a 750 Holley.
It will look like an L78 and run just as strong if not better than a stock L78
And don't worry,you can run a rectangular port intake on your current oval port heads.

And.............. $$$$$$$$$$


Correct casting heads 2K
Correct Intake 400
Correct carb 800
Engine Assembly and build 3K


Yep.....$6,200 should do it.

Of course building your own motor will save money and scrimping on the heads will too.

But if your going to do it..... you want to do it right. A sharp eye will catch the wrong heads on that 375 HP Clone at a quick glance from the front.

And don't forget your 6500 RPM Tach :)





If it's just the HP you want, as said, a freshening up coupled with a high rise intake, Carb and headers will get you there quick.

I apologize about the intake, had 69 model year in my head. Don't know why..;)

Dan..... that's not like you :)

I have a 396 that came out of a 67 SS, that I can get rid of. Let me know.

Thanks for the good info.These heads are hard to find.

I will be picking the LS-6 Car up monday. Im so excited!