408 truck dyno
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TECH Enthusiast
Joined: Dec 2002
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From: Fort Worth
408 truck dyno I dynoed 408rwhp@5700 and 436rwtq@4200. I know they look low but, it had 24 degress timing , 4.10s, truck intake, through Flowmasters, and spinning 85lb 20s. The torque curve is FLAT, it makes 430 at 3600 and still makes 400@5800. I need a bigger camshaft, it is a 230/230@112+4.
On a 200 shot with pump gas, it made 580rwhp and 677rwtq. I am very happy with the nitrous numbers. It still has the lean spike but, it is getting better. I will install a fuel cell in the very near future.
The A/F ratio is off alittle from the street tuning I did. On the street it is 12.7 and on the dyno it is 12.3, I guess the dyno can't load the motor like 4500lbs can.
What do ya'll think?
On a 200 shot with pump gas, it made 580rwhp and 677rwtq. I am very happy with the nitrous numbers. It still has the lean spike but, it is getting better. I will install a fuel cell in the very near future.
The A/F ratio is off alittle from the street tuning I did. On the street it is 12.7 and on the dyno it is 12.3, I guess the dyno can't load the motor like 4500lbs can.
What do ya'll think?
Thread Starter
TECH Enthusiast
Joined: Dec 2002
Posts: 698
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From: Fort Worth
On a 150 shot it ran a 7.39@95 in the 1/8th, shifting a 6000. Full weight and street trim. Looking at the dyno, I think I will lower the shifts to 5600. I bet it pick me up another tenth, maybe another 1mph also.
I have been amazed with my buddy's truck it runs best on the motor shifting at 6,100 and on the bottle 5,800.
I have been amazed with my buddy's truck it runs best on the motor shifting at 6,100 and on the bottle 5,800.
Thread Starter
TECH Enthusiast
Joined: Dec 2002
Posts: 698
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From: Fort Worth
They are 6.0 heads. A local guy did them, Lloyd Elliot (big in the LT1 world). They flowed 304 intake and 206 exhaust, on stock valves. No tricks no pipes, I was standing beside him while he flowed them. Small valves, 2.02s intake. Everyone said I needed bigger. I was trying to keep the velocity up, to make the lower RPM grunt a truck needs.
I am happy with the torque I just thought the HP was low (until the juice).
I am happy with the torque I just thought the HP was low (until the juice).
