LS3 bottom end - LS2/6 top end?
03-21-2018, 01:28 AM
#1
Racer
Thread Starter
LS3 bottom end - LS2/6 top end?
So i was running cam/V3/meth for a long time then piston 5 desided to scatter. Ive began saving/shopping to build a 427/TT setup, but i just had a deal fall onto my lap that i may have to use to get the car back on the road for now so these withdrawls just go away.
A friend has a Thompson Motorsport LS3 shortblock he needs to sell quick, Its a K1 rod, K1 4" stroke, -15 cc dish wiseco bottom end with ARP 2000 bolts and ARP studs. He only wants 4K for it.
Am i nuts to think buy it, throw my ported 243/LS2 intake and TB combo on it and put the V3 bak on it and get the car back on the road up on some power over the SBE stuff? I did the math, compression should be 10.4:1 so id be good on 91/meth or even going to E85.
I jsut worry the bore of the LS3 missmatch to the heads might be an issue.
Should i save the money and just accept my car is down for a year while i get the new setup together, or throw the LS3 in it and throw 17 PSI at it and get back out on the street.
A friend has a Thompson Motorsport LS3 shortblock he needs to sell quick, Its a K1 rod, K1 4" stroke, -15 cc dish wiseco bottom end with ARP 2000 bolts and ARP studs. He only wants 4K for it.
Am i nuts to think buy it, throw my ported 243/LS2 intake and TB combo on it and put the V3 bak on it and get the car back on the road up on some power over the SBE stuff? I did the math, compression should be 10.4:1 so id be good on 91/meth or even going to E85.
I jsut worry the bore of the LS3 missmatch to the heads might be an issue.
Should i save the money and just accept my car is down for a year while i get the new setup together, or throw the LS3 in it and throw 17 PSI at it and get back out on the street.
Last edited by ss4luck; 03-21-2018 at 01:29 AM.
03-21-2018, 02:51 PM
#3
Racer
Thread Starter
Yeah thats where i figured id end up going. Eventually ill switch over to some Mast heads and an LS3 intake, figure if the bottom end is built to hold a big over 1000 wheel i might as well make it happen in the long run.
03-21-2018, 07:22 PM
#5
Racer
Thread Starter
Why wouldn't they? Trying to go the other way won't work because the ls3 head valve spread makes the valves hit the bore. But searching showed me going 243 onto an ls3 bottom end works just fine
03-21-2018, 11:00 PM
#6
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My car had a LS3 Forged Short from TSP with Patriot 317's running since 2009 making anywhere from 760-850 RWHP. The 243's will fit fine as will the rest of the top end. Just make sure the shortblock is set up with a 24x reluctor.