I'd argue several points with you Hotchkis, since I've got the years on my car to prove it and owned it for 38 yrs.
The SBC springs will indeed work, and not sag enough to cause rubbing, unless you're running tires way wider or taller than stock. I've run 7" rims on the front with smallblock springs in mine since I installed them around 1975, and only recently replaced them with more smallblock AC springs. The new AC springs sit slightly higher than what I took out, but BBC Camaro springs will really give it a nose high attitude, much like mine had when I got it in 1973.
I've also been running a TH350 since around 1975 when mine I had it specially built by a good friend to take drag racing. It has a complete Transgo Competiion kit, with Corvette clutch pack, and some other changes I don't remember today, but I drag raced it for 16 yrs., and drove it on the street since I put the trans in around 1975, and the same TH350 is still in there and working as good as it ever did.
My engine is a fairly mildly built 427 bored and a bit of other work that puts out around 450 HP. Plenty to destroy any trans that isn't built right. I questioned my friend when he said he thought I should dump the TH400 and go with a well built TH350, but he assured me I'd gain a little HP with less mass, and it would hold up fine the way he built it. It seems he was right from what I've experienced.
As for headers, I haven't found any clearance issues in the swaps I've done using SBC frame and motor mounts with a BBC swap. I even switched my frame and motor mounts on my '71 to SBC mounts and I can drop my headers into the engine without any problem, or without removing the engine or even loosening up the mounts. Plenty of clearance to all suspension, frame, starter, plugs, etc. Much better than most SBC Camaros I've dealt with.

 

Thanks for that, i will check mine out to see if i will need new springs.

 

I have Hotchkis 2'' drop springs for a BB. My car still sits about an inch too high for my taste. I may put some more miles on it before I do anything to mod them. Just to make sure everything has settled.

 

Here's a picture just taken with smallblock coil springs just installed in my big block Camaro. I don't think they sit too low, or too high:

 

Luke – As 1791BB427 pointed out, you can run SBC springs with a BBC, it’s just a matter of tire size that will change your experience with them.
If you want to build up a TH350 for your big block, you can and it can hold with the right parts. We even have a tech with a built 700R4 holding a 427 with 480HP and 550 ft lbs, so just about anything can be done with the right parts. The TH350 has a lower first gear than the TH400 which is cool. We were just pointing out that stockTH350 vs stock TH400, the 400 will last longer.
Pablo – do you have pictures of your Camaro? How long have you had our springs installed?

 

Thanks for all the help, got loads of info to look into. I passed on the Big block which was offered to me, as it was a bit of a un-known and likely would need a re-build sooner rather than latter. I will be saving up and getting a re-furbed block built up by an experienced engine builder.