Spectre

I found a performnance shopo that
sells a 4-71 blower for 600 $ ..
and also a 6-71 for 1500 $

Is the 4-71 a good unit ?
the price is real tempting..

how much boost does it produce ?
Ive got a 4 bolt 350, nodular iron crank
forged pistons , vortec heads ( 98 yukon engine)

thanks 4 the replies

Damon

Including what? The blower itself is usually pretty cheap. Does it include the blower intake that the huffer sits on? Does it include the "snout"? Is the snout the right length for your application? What if it's not- will they exchange it? What about the blower pulleys upper and lower? Are they the right ratio to provide the boost you need for your engine? If not, will they exchange them for a set that will give you the right amount of boost? What about the drive belt- included? And what about the drive belt tensioner- included?

The 4-71 and 6-71 are tried and true hotrod blowers and make good power for little money. All you need is the hood clearance to fit 'em.

Damon

When setting a motor up for a blower you need to watch your compression. You don't need or want a lot. 8.5:1 is plenty with iron heads. 9:1 is getting marginal. You don't want to live of the ragged edge with a boosted motor, especially not a roots-blown motor.

Your forged pistons are a good start but even they will die a horrible death if you run in detonation for a while under boost.

Spectre

I see , ill check that asap !

Thanks man !