View Full Version : ls2 vs ls3 short block decision

07-14-2012, 05:27 PM
Hey all,

My stock ls2 short block recently went out due to my oil pump busting...or something else causing it to break. In any case, the bottom end is locked up and I am now in the market to go bigger and better of course. I've been looking at doing something different than just the usual 402 ls2 short. I know this is probably the best overall choice. What about the using an ls3 short block though? Is it also a direct bolt-in other than plugging the oil hole?

The ls3 seems favorable because of more displacement (418vs402) plain and simple. Any draw back though?

I also considered the 4.1" stroke over the 4" but I don't see alot of people running them...must be a reason.

I will be sticking with my AI 243 heads, fast 92, 4000 stall,etc,etc. The only thing I will switch is my 234/236 cam for something more optimal for the bigger motor. I know...the 243's aren't optimal either, but I have to stop somewhere!

07-14-2012, 05:46 PM
You'll just be leaving power on the table by staying with the 402.. can't think of any drawbacks other than the possible long 4.1" stroke for the LS3 but not like you have to go that big.

07-14-2012, 06:03 PM
Any plans for a power adder? What are the end goals with your build?

07-14-2012, 07:10 PM
Not really. I may add a small nitrous shot to once I leave Hawaii3 years from now.No track here so no point. I just want a torquey strong running Gto with stock gears and all the parts I'm using now....except cam. I'm not looking to set any records on a dyno...they all read differently and I have an auto anyways.

07-14-2012, 07:23 PM
Both would get you what your looking for but an LS3 418 would be a great choice if your looking to make slightly more power and to have something a little different than the typical 402 setups in the GTOs.

07-14-2012, 07:43 PM
Will the LS3 bolt right in place of the LS2 all accessories and everything?

07-14-2012, 08:24 PM
Yes the LS3 will physically bolt right in like his LS2 did.

07-14-2012, 10:26 PM
Sweet so I can still use my ai 243 heads and fast92? Im in!

07-14-2012, 10:44 PM
Yes sir those parts will bolt right on the LS3 block.

07-20-2012, 05:33 PM
what about an ls1? im want to replace my ls1 with an lsx376

Bo White
07-22-2012, 03:53 PM
Samething you have to do go ls2 you will have to do for the ls3.