Russell Baird

I'm putting together a 350 to replace the one currently in my car. The block i have in mind is .060 over, has cast flat tops, and maybe 30,000 since it was rebuilt. I have two head options, 305 heads (416 casting) and big chamber 624 heads, with less than 1000 miles since the previous owner had them redone (1.94/1.60 valves). Two cams, a puny rv cam and a comp 280 h. And three intakes, an antique torker, the torker 2, and a performer. I also have a holley 750 vacuum secondary, a 4160 600 cfm holley, and a good quadrajet. I know all parts are in good shape, just wondering whats the best setup for my car. I'm leaning towards the big chamber heads, the 280 h, performer, and the quadrajet, for some efficiency. I used an online compression calculator, and assuming no decking of the block or heads, it should have 9.6 to 1. Any help would be appreciated.

Orr89RocZ

iTrader: (20)

416 heads 280h and port the torker 2 or performer

Night rider327

iTrader: (13)

If you MUST use those parts I would do the..

416 heads, 280H cam, performer intake, mill the divider wall 1" deep x 2" long, add a 1" open spacer plate and/or adapter, the holley 600 carb.

The 624 heads are junk really. Light weight, crack prone versions of the 882 smog heads.

The 416 heads are an ok head. Not great but better than the 624's. I have seen/heard of guys getting 230+ cfm out of the 416 heads with some port work and 1.94" intake valve upgrade.

The torker 2 is about the worst intake every made. I rather have a factory iron 4bbl intake that the torker 2 on most builds.

Right now the online compression calculator is just a guess as MANY things will change this.

The stock compression height (center of wrist pin to crown of piston) on a 350 is 1.560" A lot of jobber/rebuilder pistons are 1.540" or so, putting your piston .020" deeper down the bore.

Also "flattop" is just a gen. idea as the volume of the valve pockets can range from 2.5 cc to 7.00cc

Just the 1.560 to 1.540" compression height pistons will change compression by 0.569:1

My only concern would be with the 416 heads, your compression may be pretty high and the cam is kinda small for 10.5 to 11.5 type compression.

I think you might be able to work around that some though once you know your true specs and compression.

The 280H cam when installed straight up has 4* advance built into the car. Degree the cam in, use a timing chain set that has cam timing adjustment key ways and install the cam at true 0 advance (4* retard) on chain and this will help out.

Russell Baird

The compression is my biggest concern with the 416s, i'd buy vortecs and the right manifold if i wasnt in college still. That and the last 350 with 305 heads i saw was a dog, but that might have been something else wrong with it. And i've read the 624s are junk but since someone else spent the money to have screw in studs, stainless valves, and i know they arent cracked were the reasons i was leaning towards them. I'm going to pull the known junk heads from it today and i'll try to get some specs on deck height and all that fun stuff, my cousin has a dripper to cc things somewhere.

Night rider327

iTrader: (13)

I'm not a fan of 305 heads on a 350 but when your forced with this or that part, you look at whats best.

I know the 416's flows much better than the 624's.

The 76cc chamber 624's will kill your compression. The best you can get would be around 9.1 with your .060" over flat top engine

2005Impalla

416 heads, 280 cam, old torker intake, 750 carb.

Russell Baird

I havent been working on the car since before the holidays, too busy this time of year. Anyway, as an update on my junk parts, i looked closely at the 416s, and there's this cool line between the valves on one of them, they must have been good and hot or something. Anyway, that rules them out. And it has slight dishes, not flattops. Basically, things dont look great now for any type of performance. I think i'm just going to put it together so the car is mobile, then find a vortec engine to build over the summer, and have something a little nicer under the hood. Thanks for the input to all who helped though.

2005Impalla

Pay attention to my future posts as I will be installing a vortec 350 in my Camaro in the next couple of weeks. Its a fresh crate motor that I am doing a cam swap in and the normal bolt on's.