I got a friend with a 42 Lightning with "tired" 575's trying to figure out what to do with them. He has never been thrilled with them and is at a crossroads whether to rebuild or replace. Any ideas?

I'd rebuild but junk the blowers and get an 8-71 or Whipple!

I agree with Panther.

I'd suggest selling them to some poor unfortunate soul who currently has, oh I don't know, say 496's. And start fresh!

And yea, I'd be open to parting with my 496's.

You can upgrade them to 700s with the majority of the parts.Even those blowers.

I had mine rebuilt and loved the outcome. Bored them out to 509 blocks. Went with a hydraulic cam and Morel hydraulic lifters. Changed the fireing order. Reworked the heads. Went with MSD ignition. Arizona Speed reprogramed the ECM's. The Blower Shop rebuilt the blowers. They can make the blowers stronger but I wouldn't run them for much more than 200 hours before rebuilding, depending on how you drive it. I picked up 150 hp without intercoolers. I could have got more hp out of them with the intercoolers but wanted reliability.

If you look up 10X he can tell you more about them. He helped rebuild them.

can you go more into detail.....Have a buddy looking at a boat with merc 575's

Cam,head work, more boost for ex.

Call Eddie Young @ 615 216 7449. He is in middle TN.

What hours are on these 575's?