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Alright everybody, looking at swaping an LQ4

looks like with a cam, intake, headers and a good tune it should make some real good power (400 ish)

send harness to www.jimsperformance.com and tune the computer w/ EFI-Live

get rid of PCV vavle because it dumps oil into the intake when you roll

get spacer to run a Th400 w/ full manual valve body

this is what I have so far any other advice is welcome
 

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Watermelon and fried Chicken..mmmm
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Send the harness to Jim and forget about it. Its $500 for harness and tune. You got an awesome plan. 400hp should be no problem.....what intake you planning on running? I think Im gonna run my LQ4 stock for awhile (plus LS6 intake) to get rid of the stupid and tall truck manifold. Add cam and headers and Jims harness/tune. Later on gonna pull it out freshen it up, add LQ9 pistons, L92 heads and LS3 intake, retune/cam and pull closer to 500hp prolly.
 

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What all do you have to do to the th400 to bolt it up? Is there a conversion flexplate? I've heard just drill out the flexplate holes a little bigger and it will bolt to the 400 converter but I never seen one actually
 

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Watermelon and fried Chicken..mmmm
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here are the facts about fitting an old style trans to the gen3 engines

1. the gm gen1,2 trans will bolt to the gen3 engines but you only use 5 bolts, the gen 3 engines do not use the middle bellhousing bolt on the pass side( no big deal )

2. you do not need a special flexplate, the curved 4.8,5.3,LS1- just need the t/c bolt holes ovaled out a bit and the 5.3 flex plates have a set of holes that match the small gm t/c bolt pattern perfect

- the 6.0 flat flex plate has the same t/c holes as the large gm pattern(th400 and most aftermarket th350 converters that have a dual t/c bolt pattern on them)

3. you need to use a crankshaft spacer when using a gen1,2 trans and converter there are 2 types:

- hughes gen3 crankshaft spacer part # hup-3795 $44 from summit/jegs, this spacer must be used with the curved 4.8,5.3,LS1 flexplates

- gm stock 6.0 crankshaft spacer 12563532 and longer bolts 12563533, this spacer can be used with either the flat or curved flexplate ( if using the curved style flexplate the flexplate goes on the crank first then the spacer goes on then the bolts, if using the flat 6.0 flexplate the spacer goes on the crankshaft first then the flexplate then the bolts)
 
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