Need help 12 valve wont make over 471 hp

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I have a 96 12 valve the is 40 over balanced with coated positions hamilton big stick hamilton push rods and 165 pound valve springs 215 pump no plate full cut dvs 4 k gov spring .093 lines .093 dv holders port and polished exhaust side of head roller rockers 7x20 injectors s475 turbo with stainless diesel exhaust manifold banks twin ram intake and turbo netics intercooler and 18 degree of timing i have made 10 pulls on dyno and cant make over 471 hp truck is holding 65 pounds of boost and good fuel pressure it dont pop spit or bang just not making any power any help would b great
 
165lb valve springs??? How fast do you plan on spinning that engine??

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Ya 165 valve spring and no higher than 4000 rpm for sure and i have asked them they dont know im not saying there right thats just what they told me that 18 degrees of timing was plenty
 
7x20's huh? Max EGT's are...? Turbo specifics are...?

Your timing is way too low.
 
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How about some info on your driveline you can have all the power in the world but you gotta get it through something to get it there.
 
shortbusdriver said:
Change injectors out for a properly set up 5x.018" sac would be my first change on that setup.
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Like lee said get some good sticks. .. then get up there to about 23-25º of timing and maybe swap n some 5ks. And what's the specs on turbo please don't say its a single t6 housing on street truck lol
 
1st, start using punctuation. Your posts are horrible to read. 2nd, This is another case to prove that big injectors, big turbo, full cuts, no plate, and bigger lines doesn't mean you are going to make power.

What dyno are you using? Loaded?
Can you load the truck and get the turbo spooled at a decent RPM?
Have you changed anything yet, or did you make 10 pulls w/o changing anything?
I would start by bumping timing and pulling some fuel. What exhaust housing is on the 475?
 
S475/83/1.0 t4 flange
The truck has a built 5 speed with a south bend dual disk with 4/10 gears front and back
I have tired bumping time up to 20 and 22 with no real gain in power
Hold good fuel pressure i have a fass 220 hold right around 45 pounds
 
it needs more timing, you are not trying to make power where the 75 is spooling, fact is its going to drive like crap but it needs 24-26 at least


also, the 7x10's are junk
 
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