Thread: Hot Street 396 build, dyno numbers?

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Originally Posted by pat mccarthy

well i would not take much from this but your cam adv 4 with your cam at 6000 rpm =HP 476 and at4500 rpm= 476TQ or could be this 5500 rpm =488hp and 4000rpm=513 tq with some work hard to say pick a number you like

What is the advance on the 488hp? What do you mean with some work?

both the cam was adv4 that your cam could be already? did you check the intake cent line? work would be the heads my dyno is very limted on heads and other things that may help or hurt . what you need is to really dyno this and tune it in .or just shot low say 450 hp or spend money on the dyno time

Originally Posted by pat mccarthy

both the cam was adv4 that your cam could be already? did you check the intake cent line? work would be the heads my dyno is very limted on heads and other things that may help or hurt . what you need is to really dyno this and tune it in .or just shot low say 450 hp or spend money on the dyno time

And I did degree the cam, it came out at 105.25, it's supposed to be at 105. When I put the cam in I wasn't aware of how much a chain would stretch. So does that mean the engine is going to be a couple degrees retarded? And how much horsepower could that hurt?

Most cam companies grind in 5* of advance when they grind the cam to compensate for chain stretch. Subtract intake lobe centerline from lobe separation angle to determine the amount of ground-in advance. As the chain stretches, the cam will be more and more retarded. The bottom end will lose a little snap, but the top will pick up a little and power will be broader through the range, a little less peaky at the midrange.

I went back and found this post from an earlier thread...

Advancing or retarding the cam moves the engine's torque band around the rpm scale by moving the valve events further ahead of or further behind the movement of the piston.

Advancing the cam clockwise in relation to the crankshaft improves low-end power and response.
Begins and ends all valve opening and closing events sooner in relation to piston position.
The engine builds torque quickly, then lays down on the top end. Makes the motor "peaky".
Decreases piston to intake valve clearance.
Increases piston to exhaust valve clearance.

Retarding the cam counter-clockwise in relation to the crankshaft improves high-end power, but probably not as much as you lose on the bottom.
Delays all valve opening and closing events in relation to piston position.
Increases piston to intake valve clearance.
Decreases piston to exhaust valve clearance.

like the tech added moveing the cam 2-or+ you will not see i add 4 +adv to be what i was thinking that the cam had in it from isky..... they do this to help low end ... cam had on my dyno you have to put all the @ 050 in and so would the adv too

Something still just doesn't feel right here.

Oh yeah, you're welcome 69elko ...................

Kitz

My cam has no advance ground into it. Says right on the cam card. The intake centerline is 105. When I degreed my cam it came out at 105.25, so I left it alone. Do you guys think I should advance the cam some?

Originally Posted by 69elko

My cam has no advance ground into it. Says right on the cam card. The intake centerline is 105. When I degreed my cam it came out at 105.25, so I left it alone. Do you guys think I should advance the cam some?

just run it were it is .it is on a tight lsa but moving it would give you some more low end power ? with them small port heads it may work good do you have the room on the intake side to move it 4+?

I'll have to check the clearance after I advance it. I'm not sure. I'll run it the way it is, and then when I feel like I need more power I'll fiddle around with the cam timing.

i think it will be ok where your at