I have been doing a little research on the pistons. Honestly I can't answer your question but I did find out that on the pistons I have, the wrist pin is moved up .020 which means the piston top will be lower into the bore which is really gonna hurt my compression. If you google b557 pistons you will see what Im talking about. Also they are throwing around numbers that might shine some light. I appreciate all your help and time on this matter.

 

...Unless you have the block decked, or use thinner head gaskets.

 

jumping back to carbs i like holleys, and call lunati for cams i called em they were far mor helpfull than comp or crane. what size intake runners do you have, do you have AC and power brakes gonna need lots of vacum i would think i may be wrong though you might be fine to go to a bigger lobe sepperation like 110 and smaller lift 480/460. but as i said i may be wrong

 

WARNING: Mountainous mass of energy response! Read with caution, tolerance, and understanding. Hope I am not too late. Get a comp 268H or 270H or lunati 60102 or xe262, to use with AFR195's for $1500. Fully honest 350+ to 400+ HP&TQ in a 350 cid daily driver. I REALLY like the comp cam's classic 270H magnum street cam.
I can swap you my shiny EPS intake for one of your carburetors.
If your pistons are .025" down in the hole you may use a felpro #1094 (.015" coated shim gasket) but you REALLY should surface the block's deck to 60 RMS smoothness. this will acheive .040" 'QUENCH' height. It is best to use a 6" rod and the right piston combo to have 'zero deck' but with the stock deck height. But the next best is to deck the block to ZERO when insisting to use 5.7" rods (prob' cause they are stock) then use gasket .039"-.042" compressed thickness for your quench.
Here is some good advice: Buy the AFR heads for $1500! when you take off your old crappy heads, take a dial caliper (or proper measuring device )and use the depth end of the caliper to the top of your piston from the top of the piston bore (the deck) just to get an idea you know if its level with the block or not or about how far in the hole. Once you do that and have determined you have the wrong pistons for an undecked block, get the correct 1.561" height pistons for UNDECKED blocks to replace your cast "burn a hole in my pistons" piston. Go ahead and get some good street hypereutectic (hyper) pistons like Keith Black (KB) or whomever. To use your crapcast (no pun toward you personally, I have had crap cast pistons) pistons in an undecked block will burn your top ring or just cause probs in the long run.
1) Get AFR heads.
2) Get the pistons. 6cc relief Flat tops or dish with 65cc heads. Summit has some cheapy 1.561" hypers for $87
I do not, however know the extent of their durability. You may opt for the good part that can tolerate the high performance of 400+ horses and the heat/pressure that comes with it or just burn a hole in your pistons under poor conditions. You may ask for a knowledgable tech at summit about their ability to withstand 450 REAL hp. Be sure to say REAL hp not dreamed up hp. And we all may have heard the all too often heard speech of "my stock 350 making 530hp with stock iron heads low compression and a huge cam" is taken as truth in a "don't hurt their feelings" kind of ignorant deal, sorry peeps.
3) Get the .038"-.044" quench height. Wich if your pistons are deck level (may not be exactly level) the compressed gasket thickness will be your quench height IF your pistons are level in block. If not, you will have to determine the best size head gasket with your piston depth. .040" total is perfect if you don't have forged rods, crank etc.(less stretch.) people are running .035" with all forged internals and low rpm. But they still smack the head from time to time.
4) Then get the 270H cam you'll be all set. Go ahead and get the nitrided version and the 4&7 swap you could even get a wider lobe separation ground in to allow slightly higher compression or slightly lower octane. Always use ZDDP additives and cam break-in lube from schneider race cams. No matter what cam you install. And follow to the letter break-in procedures EXACTLY. My 2Cents. This cam and AFR195's you get 400+ hp with excellent street manners. This cam and other heads =doodoo but could work ok.
Use the old performer RPM or stealth air strike gap without: 'THE NOTCH' -for best street mpg and driving. Remember if you go smaller cam to calculate your DCR correctly, with dynamic stroke based on cam design. THIS is what dictates, and helps to find fuel octane requirements not SCR.
5) So note that this cam works with this compression and shouldn't cause detonation if you size piston cc, headcc, and cam intake valve events with dynamic stroke correctly.
6) If you want a much smaller cam (I.E. XE250 this XE is WAY bigger than it sounds, or 250H & the like ETC.) you may need to go with a 10cc dish piston with 65cc head or possibly the 75cc heads with the flat tops after calculating might not though. The 270H cam is like an XE262 that handles very slightly more DCR meaning it produces very slightly less Dynamic Compression Ratio. (keep in mind the 270H is like the XE262 but not the xe268 or xe274 like some
would think.)
7) If you go roller cam use one of the larger gas eaters as they are very streetable. The main reason is that the roller cam needs to be a certain size to really gain any benefit of eating more gas to gain power over a hydraulic cam's output due to finally overcoming the added weight of the roller lifters. I believe this occurs roughly between 225 and 243 degrees at .050" lift -very generally of course. So that and bigger are going to finally increase power over a comparable cam. I.E. XE274 versus Xr284HR or the like because they will have similar power curves and output. but it is right where I believe the 'ROLLER' really starts paying off in power, besides its friction reduction. No the HR268HR isn't going to make more power than an XE268 hydraulic flat in my opinion all things being equal, for example DCR! Make DCR equal then compare cams. And you will find you are comparing flats making more power on the lower side of 230 degrees duration @.050" lift. The Rollers making more on the Higher side of 234 degrees easy.