307 chevy

Hey i was talking to my stepmom and we were talking about this truck my dad has and she want to have it as her own little hot rod. Well its a 1970 c-10 short bed with a 307 bored to 311cid hooked up to a 3spd on the column to top it off it has a 12 bolt rear. All she wants is a rumbling cam and it to look stock but she wants it to be fast. She wants me to build it next year for my senior project. So i told her what i was going to do and she liked it. So heres my ideas im not putting a new clip on the front or a ford 9inch rear end in it. I want to hop up the 307 to have about 350hp or so and with a big cam and i think she wants a/c and power steering and power brakes im not sure yet but she will most likely. she wants the 3spd and i want to put in a 4:56 rear gear and i might drop it. Oh and i dont think i can run all those bells and whistles with a big cam, so im might buy a vaccum pump to make up for the lose due to the big cam. what should i do and is the any good ideas for the future project. Oh and ap72 dont tell me to run a 350cid cause it aint happening cause my stepmos want to use the engine in it.


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Sound rumbly and be fast with a 307 in a 5000lb truck?
I'd say a Comp nitrous cam and a 100 shot.

dont buy a cam for sound. buy it for performance. the awesome sound will come if the car is beastly. get the cam that will benefit you most performance wise...

well its a short bed and will have a 4:56 rear gear so it that bad, and how is it that it weighs 5000lbs when my long bed f100 with a 390 weighs 4000lbs

Well im really just wanting a mild cam about 270 to 280 at the most plus with the headers and the purple hornies it will sound nice. does that sound good 83sliv

yeah that should be ok... if yur lookin for a mild cam that should be fine...

well what about with with all the power steering and power brakes and a/c. will the cam make enough on the bottom end power plus it has to make enough vaccum for power brakes.

yeah, i suppose that could be a problem... haha just stick with 270ish then...

any other ideas on the project.

howdy there

actually a 72 older c-10 shortbed was no where near 5k lbs. they were actually right about 3500-3600. i have the factory specs sheets to prove it. if you take it to a scale and weigh it you will see it is actually in the mid 3k's for weight.
i think you might be getting the 5k number from the GVRW plate on the door frame.
but this is not the empty weight of the truck.
instead it is the maximum the truck is to weigh when legally and fully loaded(gross vehicle weight rating)

if you put an rv cam in it and do some porting of the runners and ports and polish the exhaust ports and get some better exhaust and put a Q jet on it and HEI distributor from any '75-up v-8 chevy engine then it will go a long way to wake up the 307.
i would probably opt for a common set of 1980-86 years 4416 casting 305 heads for it, these are only 58cc CC's and with a little clean up and some 1.94 valves put in they will do really well especailly on a smaller bore engine like the old 307's(these engines were made from 1968-73 FYI ; 283 bore and 327 crank)
i always mill them a little as well, and run them on 350 engines often. not great for high RPM power, but really good fun around town stop light racing and showing off.


my first chevy ever was a 68 c-10 longbed 2wd with the 307 and 326 3 speed on the column and stock 3.73 open 12 bolt. it was a clean truck all stock original even the 503AA light green paint i gave 2k for it and ended up pulling the 307 out for a fresh 1980 305 and then for a fresh .030 TRW piston and unknown camshaft equipped 1972 truck 350 engine that i put the 80 305 4416 casting heads onto and also a th350 in which pops right into place of the 326 speed trannies. it was much fun in town with the 3.73 ratio. outran most anything locally in the low ranges, no top end of course

it weighed 3850 with me in it.

these trucks are lighter than you think, before especially.

my first vehicle ever was a 69 f100 2wd long pickup with the 240 and 3 on the column, unknown ratio 9" axle probably 4.10 but its hard to say,

you wont find a stock rear for the chevy with anything deeper than 3.73 unless you happaned across a rare over drive equipped 3 speed one that did get 4.11 in these.

otherwise only the C-20(8 lug trucks) got anything deeper. either dana 60 or eaton HO52(5200lb capacity) 4.57(eaton), 4.56(dana), or 4.10 in these.

hope any of this helps somehow

good luck!

thank very much that was very helpful haha 5000lbs i thought that was wrong.

no problem anything i can help with specifically on this engine and these trucks 67-72 CST era just lemme know

well thank you i might have to do that in the near future.

I would use the comp high energy 268 cam, this gives you a lopey idle without the loss of low end torque. I would recommend installing a set of 416 casting heads off a 305 to get the compression up. The stock 307 heads had a 74cc smog chamber and small 1.71 intake valves. The 305 heads have 58cc chambers and 1.84 valves. Since the engine has already been overbored and likely the pistons are "rebuilder" pistons which have .020 off the compression height which kills quench and compression. If your planning to do a total rebuild then I would have the block decked to make up for this, as these are the only pistons avalible for a 307 other than forged pistons which cost around $500 bucks. A set of small tube headers and Dynomax super turbo`s would sound really nice. A Quadrajet carb and a K&N air filter would also be a improvement. HEI ignition with pertronix flame thrower coil and module, spiral core spark plug wires from Moroso or the like (Do not use anything with accel written on it)
You could do some bowl port work on the 305 heads to further improve flow.
This package would give the truck a nice sound and quickness that would likely make your mother more than happy.

will i have enough vaccum for power brakes.