[Fiftydriver]

Originally Posted by old motorhead

Isn't the LSx376 an iron block? Low compression, heavy assed block (totally unnecessary if a TVS2300 is your power adder), powdered metal connecting rods.....it just doesn't add up to me vs building an LS3 block based motor like it needs to be built for the job you're wanting to do. If the motor you have now is in good shape, it's worth quite a bit. Get you a motor built, that EXACTLY matches (no compromises) what you're trying to accomplish. It won't cost any more and you'll be much happier with the outcome.

Yes its around 100 lbs heavier then the LS3 but I was looking simply for longevity more then anything.

The LSX376-B15 is fully forged, forged pistons, forged crank. The one you are thinking of is not labeled as the LSX376-B8 designed for lower boost levels.

Just checked with one very good shop and was quoted $14K for a 416 forged long block. Now that did not include the core charge discount and this was a top of the line engine with best of the best parts used throughout. Well worth the price tag I am sure, just not sure if I could remain married if I dropped this amount of cash on an engine!!! Plus add in the added cost for very high end fuel supply system to feed it and installation cost of the engine, I would be pushing $20K very quickly and thats more then I want to spend.

Just figured that with the $7100-$7300 cost of the LSX376-B15 long block, throw on my Maggie off my current motor, drop $1000 on fuel pump upgrades and figure $2500-$3000 for complete installation of motor and I would be around $11-$12K with the ability to hit that 700-750 rwhp range safely and comfortably.........

If the LSX376-B15 had a 10:1 to 10.4:1 compression ratio, I would jump all over it but just worried how the lower comp at 9:1 will feel for street use???? And again, as mentioned, I can order one today and it will ship tomorrow.