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Discussion Starter #1
The old 350 took a dump and we got a good deal on a fresh 388 stroker, so in it went.

old 350
k20045.jpg


new stroker
388001.jpg


th_388v002.jpg


k20.jpg
 

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Sounds good... but does it move good? 388ci that would be a .060 overbore right?
 

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I'd switch your single plane victor jr manifold for a performer rpm one. Thats a pretty heavy truck to give up so much down low unless you have some nasty 5.38's I don't know of.
 

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Discussion Starter #6
Im still breaking in the motor, but I can already tell this thing is gonna move.

It's a 1989 Chevy 350 block (factory roller) bored .060, clearanced for stroker rods, oil passages have been deburred and smoothed, brass freeze plugs, Clevitte 77 bearings, Scat 9000 internal/ external balance 400 crank, ProComp 5.7 I beam rods with 3/8" cap screws, full floating Speed Pro Hypereutectic (9.78:1 w/ 73cc), Hastings Moly rings, Erson .468 intake .480 exhaust lift hydraulic flat tappet cam and lifters, chromemoly pushrods, 1.6 ratio full roller rockers, Chevy 882 heads port matched and slight porting on the runners, stainlees valves with under cut stems (1.94, 1.60), Edlebrock Torker 2 intake, 7 quart oil pan, harmonic balancer, Scat SFI flexplate, new water pump
 

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How are you breaking it in? Just curious......

Make sure you're running good oil with plenty of Zinc and Phosphorus.
 

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Discussion Starter #8
Ran it in park for 20 min then changed the oil. After 50 or so miles, the intake started leaking, so I changed it again. The rubber seal then started leaking oil out the back. The coolant got mixed with the oil, so I changed it out again at 100mi. Im leaving off the rubber gasket and Im just going to seal it up with the sealer. I will then change the oil again between 500-1k miles.

I've ran a shit load of oil through this motor for break-in, especially with it being a 7qt pan.
 

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Yea, running a thick bead of sealant(RTV) on the ends, in place of the rubber gaskets is the best thing to do. It's also good to bring the rpm's up during the first few drives to help build cylinder pressure. This helps put pressure on the rings making them seat better against the cylinder walls.
 
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