|02-27-2013 11:35 AM|
You find 305 heads on 305's. You can probabily buy 2 or 3 complete 305's with $200.
You are looking for the 4416 heads. Don't forget the porting, to wake them up.
|02-26-2013 09:38 PM|
|lg1969||They will do fine on a 307 with 1.72" intake valve. For MPG they are fine, forget it for performance. BTW: the subject is 327.|
|02-26-2013 08:35 PM|
|ryder57||Ok so I got side tracked off my project for awhile now its time to try and get something done. I can't find 305 heads to put on the 307 but I did find a set of heads with the casting #3795896. The guy said they are 283/327 heads. Would thes be any good on a 307. I can get them for about $200 rebuilt and ready to bolt on. Is that a fair price?|
|02-02-2013 07:13 PM|
|lg1969||You guys are getting off the subject. The question was can a person build a 327 with left over parts. I say yes, you got a 350 block, 307 crank and rods then all you need is 327 piston. As for the cam I used the old 447 lift 327/350 hp cam on a 307 that bored 30 over. It idle very nice with slight lope to it. The cam had a strong midrange torque. Put some 305 58CC heads and you really wake that 327 up.|
|02-02-2013 10:43 AM|
|ryder57||Great sounds like I need to sell some scrap metal|
|02-01-2013 08:36 PM|
Ummm...wouldn't that be WOK's and not frying pans...lol
|02-01-2013 08:26 PM|
The only other viable use for a 882 head is to learn OEM SBC cylinder head porting hand skill.
Then, when you are done practicing porting they are best when melted down. China needs more frying pans.
Now you got the hand skills to port a better high compression head for your 307.
|02-01-2013 08:21 PM|
882 castings are 76cc chamber heads with smog controlled flow...which could possibly be the worst head ever bolted to a small block. I have used several of these heads on my race boat...as anchors!
|02-01-2013 08:01 PM|
Find a cylinder head with a small combustion chamber.
882 heads are useless and usually cracked too..
If the valves are 1.94x 1.50 and usable keep them and the retainers and locks.
If small 1.72" valves diameter ditch the heads whole.
Find a better head.
On the 307 bring the piston to TDC exactly and measure the piston deck clearance @ TDC.
This will be a whole different motor with a high compression cylinder head on it.
With a 882 head on it its no surprise your friend gave it to you. It would be a very lame motor.
You can fix that.
If you want any chance of using the thumpr cam in a 307 working well you need a high compression ratio+ head port flow
stiff gears and a converter.
You want a cylinder head with a real 53cc to 58cc chamber volume (measured) and a thin .015" head gasket.
The 307's piston deck clearance @TDC matters.
|02-01-2013 07:36 PM|
|ryder57||Ok so I started taking the 307 apart and inspected the heads and they are not 305 heads. They are the "882" casting number heads with the big valves. Should put them in the 350 block and build it since they are bigger heads?|
|01-30-2013 12:17 AM|
Will need serious rear gears and a serious stall converter.
If you are not willing to do that , pass on that cam.
|01-29-2013 10:19 PM|
|ryder57||How would a Comp Thumper cam work with this set up? Duration@.050" 227/241 lift is .511int/.497 exh I found one really cheap a guy bought but never used is this to much cam?|
|01-29-2013 12:07 PM|
For your modest goals and budget I'd just use an "RV cam" in the 205-215 duration range, clean up the bowls and chambers around the valve seats, run flat top pistons with the 305 heads, a moly cast ring set, a stock type timing chain will be fine, stock crank, rods, valve covers, rockers, pan, etc. I would step up to a m155hv oil pump, but otherwise mostly stock everything else except maybe some headers and as said mild work on the heads. Maybe a used performer or RPM intake if you can get one cheap, a plain jane 600cfm holley vac secondary carb, a rebuilt HEI ignition with a stock module and maybe a hotter coil, recurved of course.
Just keep it simple and you'll be able to get close to 1hp/ci on a shoestring budget.
|01-29-2013 11:46 AM|
350 block into a 327
I agree with the k.i.s.s. method. If you're on a budget and money is an issue, maybe it would be simpler to ust clean up the 350 block and bolt the 305 heads on it. The smaller combustion chamber would boost compression without having to re-work anything. Its the most economical way to get a good running engine. Then save your dimes for a point down the road when a more radical build is in the budget. Good luck with whatever you decide to do.
|01-29-2013 11:15 AM|
You do not pick a camshaft solely by what the compression ratio.
Pick a cam that will do the job you want the motor to do.
Pick the cam duration based on the rpm range you want the power to be made at.
Then pick a compression ratio that is usable with the intended fuel.
Obviously if you limit the fuel choice to a low octane 87 octane then you need to go easy on the engine compression ratio.
just remember low compression ='s low torque output.
A high performance engine needs a high performance fuel.
For a high performance pump gas motor using a 92 octane fuel a compression ratio of 9.8 to 10.5:1 works
real well. And the cam , from that point, does not have that much effect on that.
On pump gas, once you get beyond about 10.5:1 cr your chance of having engine knock problems
greatly increases, reguardless of what cam is in that motor.
You want a generous compression ratio, but not excessive for the fuel in the tank.
More compression ='s more engine torque output. Up the the practical usable limit of the fuel in the tank.
Beyond 10.5:1 compression consider it EXPERIMENTAL, as you are at or real close to the practical street operational edge of GOOD pump gas.
10.6,,,10.7 +++ expect that the motor may/probabily will want more fuel octane that wahts in the pump.
Allowing he engine to ping and knock because the cr is too high for the pump gas fuels ability to resist detonation ("octane"), will result in engine damage. Its just a matter of time.
Just realize a cam cannot be a big cam and be a small cam a the same time.
Pick a cam based on how you will really be using the vehicle and the gear ratio.
Placeing or establishing the RPM @ 60MPH ("cruise rpm') is a good bench mark.
Bigger cams need a high stall too, especially in a small cid engine.
Intake manifolds. If you want a powerfull 307 then a RPM manifold and 750cfm carb is great choice.
That same motor will want a cam and gear and a converter too.
If you area after big horsepower do not dummy it down with low horsepower parts or a small carb.
A 307 makes (more) power like any other motor, By breathing more air and processing more fuel.
Yup it will need rpm.
But of you do not want a big horsepower, and want a low rpm , stock like cruiser, then keep the cam small
and use a low end torque type intake manifold.
The RPM manifold and others (dual plane hi rise) like it that have a full plenum divider have broad power range.
If you want to cam it up for power, you want stiff gears. ( A 3307 is much like a 283 or 327, it likes RPM, when hot rodded.
If you are not willing to do that, keep the cam for your 307 relatively small.
Like stated you don't really want or need a 2.02" intake valve for a 307. A 1.94" valve gets it done.
Especially when the head is ported for improved air flow. Flow is power. A 1.94 x 1.60 valve set is ideal for a high perf
street 307. A 1.94" x 1.50" valve set gets it done too.
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