I have a stock bottom end lt4 block with afr190 Comp package
Gm 847 cam 236/242 548/558 lift 1.5rr ported intake stock throttle body
24lbs injectors slp headers 1 3/4 3 in flowmaster all the way to the back
Centerforce clutch
My question is the car will not break the tires loose from a 10mph roll on street tires now if I dump at 2000rpm they will spin all day through 1st 2nd and 3rd. the car has been tuned by a very good tuner locally I mean the car drives great this guy really knows his stuff name is tony bishop car pulles all the way to 6600rpm feels like it will keep pulling but dont feel like testing bottom end at 3000rpm it comes on like a 200 shot i mean its fast but tony says that cam doesnt make any power under 3000rpm thats why it does not feel as torque at the bottom now my friend as stock ported lt1 heads and extreme energy cam and all the boltons he can spin them from a roll in 1st but he cant touch me on the street I know that my throttle body,exaust, and injectors need some attention but I just want to see if anyone else with this cam is haveing the same symptons thanks chrp3rd

 

the 847 loves the upper RPM from what ive read, and in a drag racing scenereo id think that the power commin on like a freight train at 3k would be awsome. you wouldnt have to worry about traction as mach as with a cam that builds power down low, but if your in it just to keep goosin on it at 10mph and want the backend to come loose, than maybe you want a cam that builds power at a much lower RPM, just a though.

 

That cam's powerband is like 3000 to 6800 I believe. If you have a good tune that would be an awesome strip cam, because you're never really under 3000 RPM when you're racing anyway, so you're always getting good power. I personally wouldn't want to take my car to 6800. I'd rather make power from 2000-6300 on a stock bottom end car. pushing an LT1 to 7000 just spells disaster to me...

 

It will make power even past 6800

I have driven a friends with it, except his 600 lift springs give out @ 6500rpm. Past 5k its nasty, past 6k its a monster.

Power band feels like a smooth transition on my cam. On the 847 it feels like a small turbo spooling up or something.

With your combo I would expect enough to break the tires loose by goosing it. Been to the dyno/track lately? Check wires. Always check wires when something goes wrong.

 

What springs does he have, BTW? I bought Comp's 978 springs, supposedly good past .600 lift... I was wondering what RPM they were good until, before they started to float.

 

I know with a 383 it has no problem breaking the tires loose...lol, But on less cubes I could see it having a more marked powerband. And yes it makes power to and past 6800 even in a 383.

 

He has some dual coil springs. Not beehives though. Forget the brand but they are advertised for .600 With 1.6rrs the 847 has something like .595 on th exhaust. He is buying something that is good to .700 ??? Ill try to find out what they are. I would not run the 846 with 1.6s on .600 springs.