Atomic

iTrader: (42)

Certainly a bigger turbo will make more power, but from what he said above thats not what he is after. A s480 will be much easier to fit and generally behave better and more friendly with his goals. If he wants 1200+ then sure the s500 series would be much better, hell I even thought about upgrading to one at one point.

With a 80mm a 416 will spool it no problem and a converter that big will just make it less street friendly and probably blow through the turbo's powerband very quickly.

I would go for a around 9.3-9.5 compression. Will meet your pump gas requirement and be able to make that power without using e85 or meth and still be peppy driving around.

kbracing96

iTrader: (26)

And Am I reading this right, your putting this monster turbo motor in front of a 4l60?

03sierraslt

iTrader: (22)

I hope not.

George C....

If he decides he wants more then that power as we all do then a s480 will be choked up..run into huge back pressure issues and can lead to a hurt motor.....didnt you go thru this same thing with a 408?

03sierraslt

iTrader: (22)

Out of curiosity, what do you guys consider to be too much back pressure on turbo setups? It seems to me I see 2-1 a common ratio?

George C....

2:1 is borderline

1:1 is ideal but most single builds wont see that
1:1.5 is target
2:1 is what most average see and it shows with back half mph

Atomic

iTrader: (42)

If he decides later he wants more power then certainly a turbo upgrade would do it or just up the boost, but he didnt say he wanted to oversize it now for the future. His requirements are pretty clear, and there is no need for a donkey dick turbo.

Backpressure is not a boogie man, especially on a street vehicle. I dont know what you are referring to with any issues I had on mine? I maxed out the s482 I had, not sure what you are getting at? My build wasnt an all out drag car, it was driven on the street as a street vehicle.

Most of the KB and trick kits you see guys with will have 2-3:1 backpressure, which is fine and about what any factory turbo car will be. More power can certainly be had with a huge turbine and lower backpressure, but it will have more inherent lag. That is not debatable. Fine for a drag car, not so good for a street car. 2:1 is pretty good for a single turbo v8 with a street type setup.

George C....

So a 82mm on a 408 and now youre telling him a smaller turbo on a 416........
Back pressure is shown on the track by how much it picks up
Also to much back pressure will kill a turbo and easily destroy valve springs
Not saying for him to run donkey dick turbo but youre telling him to run too small of a turbo for a beast of a motor

Hell some 416s can run twin 80mms....hell ghostryder is doing just this

Op is gonna have to decide what he really wants based on what he has...his trans with anything but his motor NA wont live long...also has to realize how much motor he actually is packing...for only 800 goal he could toss a 5.3 with a s480 and do all he wants

Atomic

iTrader: (42)

I'm telling him smaller because his goals are not what mine were. Yea I ran an 82mm on a 402, but also made 1000hp. He only wants 800, which is perfectly do able with a smallerror turbo and will drive much better on the street than a big one.

caviness

iTrader: (12)

I want to do the 416 cause it will have pretty good power down low before the turbo comes on , when the trans lets go ill upgrade with 4l80 but that's what I have for now and it should be ok on the street, might not last long at the track. 800rwhp will be fine in the truck for now if I decide to go more then we can turn up the boost or upgrade the turbo , but for now just want something not to laggy , just medium size cam for turbo not stock cam , and whitch turbo kit for what I want I know there is a few to chose from , also what will I have to do on the fuel system to make the power with room to turn it up if I decide , if it turns out to make 800 rwhp and later I can turn it up into the 1k range with some meth and more boost that might be ok for latter,