Head specifications 3927185 1970

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Can anyone give me the specs on these heads as far as how many cc's the intake runners are. I know they are probably 1.72 I am hoping they are 70cc but what beyond that. I have some boat anchor 624 with brand new 194 and z28 springs to put in.

Thanks

[MonzaRacer]

They are stock 307 2 bbl heads, small valves and should show up in the 72 to 76 cc range(depends on the previous work and how the factory was going to apply them)
what they would do would be fly cut ,so to speak, as they cut the intakes and exhaust to open the chamber up a few cc.I have seen them actually unshrouding the valves ,mostly on lighter cars like camaros and novas.And they would leave the tighter compression in hopes to make a slightly higher power outy put in say chevelles, impallas and trucks.
The work very well on low to mid rpm small bore engines. They can be put on 305s but they are for a larger bore. They are a great head for 283s and even a mild 327.
They can be opened up for good port velocity but they are all in by 5000 to 6000 on small engines and choke bigger engines.
The do make great torque.
another head that was patterned in the same mold but a little heavier casting is the 991/993 truck heads.
A good thing for these heads is to up them to 184 swirl polish valves and then you use a rounded course roughing stone and "throat" the portsdown to the guide.Another trick is since it is maxed in lift use below .500" you dont need super fast valve action, you cna use a head machine for installing guides and seats and spot the guides and I remove around 5/32 of guide height in the ports and get some real awesome velocities.
I actually built a 355 with a set of similarly done 991 truck heads and this engine with a split lift cam made some ungodly torque. i used them with my pistons .018 in the hole and a steel shim gasket and while it did like premium only it was tough.
I personally have a set of 185's and they have had the 184s added and I had added 160 exhaust and we were going to use them to choke a 355 for my nephews s10 but he gave up so I am going to run them on a 283 in my Monza.
Really depends on what you intend to use them for. A real wierd engine but it does work and make scary torque for a stroked 307 is to add either a 350 or 400 crank.
Now while you may not think it would work smaller bore long stroke engines with these heads can get some scary port velocity going for stock heads. Shaving them will bring the compression up. Be care ful on cam selection and milling if used on a 305.
I have built several 307(younger kids, less money, and we had great results, but not very a good head for big engines.
I like to use on hand parts as a lot of times I just dont have big cash for aftermarket heads so I use what I have.
They do take to porting of sorts just dont get super radical. Be judicious and sparing and only try to straighten the ports slighly. Removing restriction and smoothing is all thats needed .
As for 624 Those are junk, weak thin deck crack prone heads. Only fit for grannys impalla and if the have crack even dry cracks , junk them or sell them to someone needing stockers.
As for trying to install 194 you would have to open the chamber a lot BUT the Z springs are my mian stay spring for most street builds.HeckI have them on my SR torquer heads with bigger valves(all used and rebuilt by me), set at 100 on the seat and the springs still ,after over a year and a half (90 miles aday 5 days a week) they still spec at 95 to 98 on the engine and this is with a LT4 HOT Roller cam.
Good luck

[Footjoy]

WOW Thanks these heads are on a 307 I wish had the time and money to stroke it. but I have to sell stuff when I'm done and nobody wants this complete 307 with 2, 3,000 miles on it period. So stroking one I would own for ever. I do appreciate your responce. The thing I like is the knowledge gained along the way.

Thanks again

[MonzaRacer]

Pick up a set of forged 307 pistons, and build the crap out of it.
My buddy has built 3 of them and no one believed they were 307s.
Heck it used to be a big thing to stick a 327 crank in a 283 (it makes a 307) way back when.
Honestly the 350 crank in a 307 brings the cubes back up and makes like a 330 engien with lots of torque.
The big thing I did was simply chuck the pistons up in a lathe and cut a little off the top and slid them in and tada, lot o torque.
The 307 with a 400 crank is even better than the 350 crank in a 305 block. Its even better at it allows you to unshroud the heads. And if you find some good aftermarket 400 length rods you can use stock pistons with very little mods ( I really for get all of the compresion heights but it isnt that hard to get it right)
The torque is the big winner and you can fiband tell them its a 307!!! hehehehe

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What would you get if you put a 400 crank in a 307 and put vortec heads on it? Would it run strong? Do you have a machine shop? Iam going to run a tune port so anything after 5500 rpm is really not important. I think it has been bored 30 which makes it about 3.999 bore

[MonzaRacer]

No it puts it at 3.915, The 307 Chevy has a 3.875 bore factory.
The fun part is mix and matching rods/pistons as I am looking for my notes on the 350 cranked one(we did the measurements for the 400 cranked one, one of my friends did some work on one and I know of another one that was even done.
It drives me crazy when I cant remember all the details of engines I work on.
I do have notes but I need to find them.
As for the Vortec heads I would think they would work awesome but I would think of using aftermarket parts for the TPI.
Just a thought.
Neat thing is everyone thinks 307s are dogs but my buddy had a forged piston 307 and 5.13 gears in a 68 Impalla and got it into the low 8s in the 1/8th mile and I figured that was a real world proof of a 307 in a huge car going fast.
4390 pounds and it ran low 8's! Very credible and everyone gives them away and I use the cranks to build large journal 327s from 350s.
Lee

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Let me know when you find your notes I would like to know what rods and pistons were used

thanks Greg