I did not find enough feedback on any idle/low rpm drive-ability or possible surging.....real life driving experience - not just dyno charts and 1/4 mile stuff. What's going to be your car purpose re: a street machine, track car etc.
I couldn't even find dyno stuff on it, other than GM propaganda!
Imho, I'm disappointed in my 525.
In terms of idle, it does have a nice choppy idle to it.
[ame="http://www.youtube.com/watch?v=HIAFwqaK8CI"]RCR superlite SLC First Start - YouTube[/ame]
It does buck a little bit at low speed, but not horribly so. I'm not certain if it's the engine or the engine/clutch combo, but it is a bitch to get going from a stop. Normally I'm used to easing off the clutch and giving a little bit of gas. Here you need a lot a bit of gas because it loves to stall. Even on the dyno my tuner was swearing up and down at it. Adjusting the ?idle? timing though helped, so it's not as stall happy. Honestly, my 408w with a big-ass cam is easier to drive.
I think I would hate life if I had to drive this engine in traffic constantly.
In terms of power, it was a bit of a let down - barely 530 flywheel hp with headers and intake. Wayne also has quite a bit of extras (ported heads, etc..), so it's not fair to look at his engine. And, honestly, if I'm going through that nonsense of buying a crate engine and doing heads-off work, then i'll just do what I did for my 917 - go to Katech and buy engine. Yes, they're expensive, but there's no 2yr wait and I know I won't get an engine where rocker arms are 90* off the valve spring at 0 miles and I'm told it's due to "shipping damages"
In terms of GM build quality, hah. I originally bought my crate engine because I wanted peace of mind knowing it was assembled by the factory and would stay together forever just like an LS3 corvette. And then Shane told me the horror stories of the crate engines he's put into cars (e.g., no oil pressure, oil leaks out the rms, etc...). So I figured maybe Shane just has massive bad luck. And then I searched LS1tech and found at least 25% of people have problems with their LS crate engines. And then as I was working on mine I found numerous issues (e.g., crap in the valve covers, flexplate was only on hand-tight, waterpump was only on handtight) that shouldn't be. But it survived the dyno so I'm hoping maybe just the accessories weren't bolted on snugly and that's the worst of it.
Oh, and warranty, hahahahahhahahahaha. I bought it for the warranty, but then I read on LS1tech about your chances of success in the event of a claim.
So, in a nutshell, I would not do EFI again (I <3 carb) and I would not buy a GM crate again - it's not a sleeper and build quality can be suspect.
Also, don't buy the GM ECU thinking 'oh, it's for the 525 or the 480 so I won't need a dyno tune, it will be pretty close'. My a/f was pretty wonky and my timing was horrible - at some points I was at 15* timing
