Anyone used the summit Iron LS blocks? Thinking about getting one for an "iron ls1" turbo build. Done a little searching and most reviews seem positive. Have seen several reviews that said it showed up a little rusty, though.


Anyone ran these? Any extra machining needed before assembly?

 

There is some kind of coating on them it seems when you get them, they kinda look like hell but I've yet to see anything that would require "fixing". Not putting it together for a while but I will update when we do.

 

I bought one, and it had rust in the cylinders. I put ARP main studs in it, and it needed align-honed for that. Just had them bore it oversize a little to get the rust out.

 

There's been a few posts over the years that these blocks are often out of spec. Low bid machine shop/supplier I'm sure.

If you go with one from Summit, have a shop check it's measurements.

 

I thought I read in one of those posts that ATK supplied them with they're LS blocks...

 

hmmm. Seems I may as well just buy a junkyard engine if I'm going to need a machine shop to get involved either way.

 

I bought the 6.0 Ltr blocks that they sold several years back, supplied by ATK.

I had to get the cylinders honed to size With torque plate. They were too tight.
New cam bearings installed.

Once I started assembly, I found the #3 main cap to be off center a bit. It took some massaging of the cap and bearing in order to get the clearance within spec.

The 408's running now and no issues so far. But it took a little bit of money to get it right.