Re: LS6 L78 4557 jets??
 

Thats awful lean....a little LT1 takes 70's and 76's...

Re: LS6 L78 4557 jets??
 

The 70 L78 Nova came stock with 68 primary and 76 secondary jets in the Holley 4150. This may be a bit lean - check the plugs and size um accordingly,

Re: LS6 L78 4557 jets??
 

Thanks Dean! Surprising that the LT-1 would get bigger primary jets than an LS6 or L72 - go figure!
-Sam

Re: LS6 L78 4557 jets??
 

When re-jetting, what combinations have people used with the stock L78? I was thinking about going larger by 2 or 4 sizes.

Re: LS6 L78 4557 jets??
 

I have 72 and 76 in mine. Runs great that way.

Re: LS6 L78 4557 jets??
 

Here is THE setup for these carbs, courtesy of COPO Pete:

72 fronts, 84 rears...with a 65 power valve in the front and a plug in the rear. Made a world of difference in our cars...

Re: LS6 L78 4557 jets??
 

https://www.yenko.net/ubbthreads/imag...mlins/grin.gif