As most of us know the weak link are the 256 Weiand blowers on these motors. If something goes wrong with the blower there are no hard parts available. I found a company that takes the time to get their blowers to work with the 575Sci setup. Dyers Blowers makes their own cases and rotors. They took my TBI plates and resized the holes to fit their 8-71’s They also took my thermostat housing and machined an adaptor so it also could be used. They also machined a new lower pulley so I could use the serpentine belt setup. I will be running the 8-71’s 5% over for 6-7pounds of boost. I will start the installation tomorrow and I will post photos. So glad to find someone so helpful as Gary and his son Bill.

http://www.dyersblowers.com/

heard some good things about them, had i not found the deal i did on the 420 megablowers i did they were my next call

What throttle bodies does that use? Two Two-barrel TBI's?

Yes

How much $ ?
What is your HP gain?

I paid $3300. per motor + shipping

As for HP gains...I'm sure there will be some but I have no idea.

The lower Pulley (like the one they machined for you) is available from The Blower Shop (steel). Tstat adapter is available from whipple and the Throttle body adapter was a direct bolt on for me. I am about where you are at as far as over-driving and am at about 9.5psi on my stripped littlefield 871.

Knot trying to jack up your thread ... Looks like you have a killer set up going. I have the Blower shop set up. 6-7 pounds of boost. And the support has been great. I have the Arizona Speed set up and I really like it. The stock merc fuel injection has been awesume so far.
Chad

You have the 250 blowers correct? What are your HP #s? And did you do the aluminum heads as well? I've got a 29 fountain with a 575. And my name is Chad as well lol. Would like to talk to u more about it. Can u please PM me ur phone # if that's cool?

Thanks Chad

looks good!