I just seen the lt4 conversion kit in the 'new products' section of my new summit racing book... says it is good for a proven 425+ horse power and includes the lt4 heads, valves, springs, red intake manifold, HOT cam with 1.6:1 ratio, bow tie roller rockers, and all gaskets... all for the price of $2,329.95. It sounded cheap enough to me for all those horses, but then I got to wondering what this was going to do to my 96SS' 6-speed and rear end.? And what else would I possibly need to upgrade on my car to handle this power (if anything).?

 

Traction is what kills the rear end.

 

9 inch 12 bolt or at least aftermarket axles differential for the stock 10 bolt

 

I doubt you would brake the stocker with street tires. If you do it will be from a rough launch. if you get that first just take it easy on launching for awhile.
also. that is 425 hp with dyno tuning...... dont expect 400 without it.

 

I ran a set of our LT1 heads & a cc306 in my daily driver for 10-11k miles with an aggressive clutch (sintered bronze ram), and motive performance 4.10's.

I wasn't terrible about beating on it, but I wasn't easy with it by any stretch of the imagination, and it was just fine. As mentioned, the key was that I was on street tires. I ran ET streets once as soon as I bought them however. Of course after one relatively mild 4500rpm launch I went straight home & took'em off LOL.

I wouldn't worry about the stock rear with street tires really, but if you're into drag & plan on hooking it up, I'd sort out potential driveline/chassis issues prior to putting the $ into making power .