LS3 top end swap build thread
LS3 top end swap build thread Ok this is not my first build, I blew the original LS1 motor when the oil pump failed, cracked the block around the crank snout. I swapped an LS2 and an LS6 intake with a 226/230 .598/.601 111 +4 and longtubes in its place. Tuned the car using HP tuners. Never had the car on a dyno but track times were best of 12.6 best mph was 113. Best 60ft was 2.09. So, fast forward a few months and I have decided to swap the LS3 heads and intake onto the stock LS2 bottom. This time I decided to take pictures and make a build thread. Hopefully this is in the right section, if not please move to the correct place. My car is a 98 NBM Trans AM that needs a paint job and wheels REALLY bad. So to start the build I used a very good step by step write up I found on this site for dropping the engine out of the bottom. When I pulled the LS1 and set the LS2 I did it through the top and I can tell you for me out the bottom is exponentially easier! Ok so I am just going to post a few pics of the progress, I am still waiting for the LS3 parts, we are doing a trade.
Well according to the directions, this was one of the most important steps!
The wife was not to be outdone!
My dad who helped get the motor and trans out!
Last edited by mklaus1; Sep 30, 2013 at 10:57 PM.
Cleanup started
All Cleaned up!
I had to take a break during my project to take my little helper to find a friend. He loves frogs and this is the biggest one we have caught so far. He holds it all the time and even got in the bath tub with his frog who he named Cutie!
I will continue to update as I progress, if for nothing else than a memory box for myself. If anyone else is planning on or working through this type of swap and needs some help, I would be happy to provide any help I can!
Also, I would REALLY appreciate any input from cam experts or people with experience with a similar sized cam in a similar setup. I am planning on running the 226/230 .598/.601 111 +4 on EPS lobes in the new build. Any predictions on how this cam will perform? I will have longtubes and true dual exhaust. 98 MM Lid and 85 MM MAF or possibly a blade MAF in a 4" tube. Thank you so much!
Matt
Matt
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Updates So I have my LS3 heads and intake now. I have installed dual springs on the LS3 heads and my brother polished the fuel rail for me. I should get my billet aluminum 92mm throttle body and Prothane motor mounts tomorrow. Here are some more pics of the new parts.
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Thanks
Last edited by mklaus1; Sep 18, 2013 at 09:52 PM.
More updates I received my billet 92mm throttle body, Prothane motor mounts and injector adapters. The adapters are really nice and fit perfect, they snap into the LS1 harness and LS3 injector perfectly and look like a factory part! The throttle body looks great! I am not sure about sensor outputs and IAC operation but the sensor and IAC bolted on and fit perfectly. I am impressed so far! 
Pictures attached.
Pictures attached. 
I just got my stainless headers today! Pic attached! I also started to flycut my pistons tonight, hopefully I will have them finished tomorrow, I will upload pics when done. My head gaskets are on the way, Felpro .04 compressed thickness. After that I will get the head milled and then it should be time to start the reinstall! 
