lq4 402 help
#1
lq4 402 help
I don't know a whole lot about the engine (no build sheet). I do know that it is a 402 with 241 heads and yellow valve springs. truck intake manifold with stock throttle body. the cam sounds weak also (no cam spec card). the truck dyno'ed 285 at the wheels with a manual vb 4l80, 2500 stall torque converter, 9" 5.43 ring&pinion and 37" tires. probably about a 30% drive train loss. I'm disappointed in the numbers. what can i do to squeeze out an extra 100rwhp naturally aspirated.
#7
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as said above, intake/valvetrain addressed first. a popular upgrade is a tbss intake manifold with a 90mm throttlebody. im no guru but i would guess a cam in the high 220's/low 230's intake/exhaust duration would work well would that converter. also, is the trucks pcm tuned? i would think i 402 even if it was choked with a baby cam and small intake would easily make over 300hp even through an 80e and 37's
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#9
Thanks for the info. The truck was dyno tuned at Cunningham motorsports. I believe it made power between 3500-5800. Is the fast Lsxrt worth the time, or will I see similar improvements with the tbss intake? Are the 241 heads holding the engine back?