La1 3400 sfi top half swap

[Guest]

Hey guys i have a 99 grand am with the 3400sfi engine..i was thinkn about putting a cam in and have heads built up a little with roller rockers the ls6 valvesprings stainless head gaskets etc...my question is how much extra power will lower stock internals take?? Do i have to put new main bearings, piston rings new connecting rods in??? Or can i leave stock bottom end????

[caffeine]

The bottom end can take quite a bit more power over stock

[Hard Driver]

Hey guys i have a 99 grand am with the 3400sfi engine..i was thinkn about putting a cam in and have heads built up a little with roller rockers the ls6 valvesprings stainless head gaskets etc...my question is how much extra power will lower stock internals take?? Do i have to put new main bearings, piston rings new connecting rods in??? Or can i leave stock bottom end????

It's not horse power but rpm that will kill you engine.Keep it in a safe operating rpm range and you will be ok .

[caffeine]

Generally I find the stock bottom end is OK to 7000 rpm.

[Superdave]

Somewhere in the 400 HP range is where they seem to start having issues. Keep the tune good and keep it below 7K RPM.