Newbie with 307 Questions?

I just got a 1969 C-10 with a completely stock 307. I got it "running" well enough to get it out of the woods it in was and where I could actually get to the inter workings of the truck without the need to spray myself down with deep woods off to keep the ticks off of me. Know I need to plan what I am going to to next. I can get it to crank but will not run well at all. Has no pull and oil leaking everywhere (gaskets), I am getting ready to brake this thing down but want some ideas about what to put it back together with. I don't what a supertruck, just something to have fun with, and use around town. AND NO I DO NOT WHAT TO SWAP IT OUT FOR AN 350. Not for what I want to do with this truck.

Here's your best shot....
http://www.amazon.com/How-Rebuild-Yo...0793522&sr=1-5

I have read that 305 heads from casting 4416 or 2601 with 1.84" intake will work well with the 307 block.

Quote:

---

Originally Posted by gte436e

I have read that 305 heads from casting 4416 or 2601 with 1.84" intake will work well with the 307 block.

---

So will a set of the old "Power Pack" heads.
When you go throiugh it, mild cam, good intake and exhaust, be conservative with a good carb and you'll have more then enough for that truck.

THIS is where I got the info for the 307 I put together...joe

Thanks Joe, I checked it out, lots of good info there.

What aluminum heads could work with the 307?

Post #1....

Quote:

---

Originally Posted by gte436e

I don't what a supertruck, just something to have fun with, and use around town. AND NO I DO NOT WHAT TO SWAP IT OUT FOR AN 350. Not for what I want to do with this truck.

---

Post #7....
"What aluminum heads could work with the 307?"

Is it just me? First you are adamant about retaining the 307, then you seem ready to lay down $1100 for a set of aluminum heads for it when you could make way more power with a boneyard 350 using boneyard Vortec heads. In my opinion, spending money to build an aluminum-headed 307 would be like administering steroids to a midget.

Now that I have that out of my system, I'll try to answer your question. I might try using the Edelbrock #60879 heads. They have 60cc chambers, so it would be easier to make some decent compression ratio with them. The intake runners are 165cc's, so you could more easily keep port velocity up with the small displacement 307. They're drilled for the early intake manifold bolt pattern too, so that makes it easy to mount any of the early Gen I (55-86) existing hot rod intakes to them. They use centerbolt valve covers, so the early valve covers won't work. Valves are 2.02"/1.60". I would call Edelbrock and inquire about using them on a 3 7/8" bore (3.875") motor. Now, if you're going to bore the motor and install new pistons, then the bore will be 30/1000's larger at 3.905", so there may or may not be any physical or flow limitations between the valves and the bore, depending on the valve lift of the cam you will use. I don't know the spacing of the valve centerlines on the 60879 heads. Call Edelbrock and talk with them.
http://www.edelbrock.com/automotive_.../contact.shtml

So finding a set of 305's with 58cc chamber would be much better.

By the way Tech i liked the book too, lots of good information. I have a friend you has a 305 in his garage he may sell me. I may just go with it instead. Would it be better than tying to get something for nothing out of this 307?

That write-up on The H.A.M.B. is a good one. The 307 has indeed gotten the short end of the stick in the reputation department; properly built, it can be every bit as good as any other "Mouse". One of the performance magazines (Super Chevy, or maybe Chevy High Performance, or one of the others) did a budget 307 build some years back, and got a very good performing engine by just following the basics of performance engine building. When you look at the engines pedigree, you will find that it is the homely sister of the great Corvette engines of the late fifties and early sixties - and they were not slouches. Dress her up right, and she will not be unattractive, at all.

After everything I have read, this may be my plan.

305 heads 416 of 601 castings.

summit k1102 cam set

intake ??? z28 style maybe 2101

Holly 650.

GM HEI ignition

How would that match up???

I just rebuilt a 307 for my friend...got advice here and it all made sense. We were in the same boat...we had the 307, didnt want to buy a whole 350...work with what ya got!!:D

I used the same exact setup with the K1102 cam and 416 heads. The boost in compression using the 416 heads will put some punch into that motor. The 601 heads with the smaller cc would make the compression a bit too high for my taste. The Summit K1102 is a great match for the 307 with those heads, it will give good torque and good driveability.

Your other questions:
Intake - 2101 or similar dual plane aluminum will be great.
HEI - perfect.
Carb - 650 is fine, maybe a bit big, you can always jet it down...a 600 should be perfect.

Also, a decent set of headers will be worth some extra power.

You'll have a nice street motor when its done.

Good luck!

Quote:

---

Originally Posted by 63BoxNova

650 is fine, maybe a bit big, you can always jet it down.

---

Every time I see this statement, it gives me pause, wondering what area of science it came from. I have been in some heated discussions with another member of this board about this statement. According to everything I've learned over the past 50 years, the throttle bore size and venturi size dictate the CFM of a carburetor, not the jetting. The jetting you choose only changes the relationship between the amount of air compared to the amount of fuel that is being pushed into the ports by atmospheric pressure with the intake valve open. A 650 CFM carb is a 650 CFM carb, no matter how you change the ratio of air to fuel by changing the jets.

Tech,

Does that set-up sound appropriate for this engine?

I'm with Tech 100% on this one - you can not change(reduce) the cfm without changing the physical size of the carburetor body or adding a restriction plate (like sanctioned race bodies require - different story altogether).

That said - If you want a bit of balance between performance and economy, go with a 600cfm carb - like an Edelbrock 1406. Electric choke and very solid design. You may find it a bit rich out of the box and need to re-jet, but try it in the stock configuration first and see if you're satisfied with the performance. I've used a lot of the 1406 carbs very successfully.

Summit SUM-210216 is a 750cfm Quadrajet (rebuild) which is also an excellent carb and was GM's choice for a lot of years on everything from 305 - 454. Great response off idle and there's nothing like those big secondaries when they come to life for a bit of tire chirp in second gear and a wonderful deep growl that lets folks around you know you've got more than a timid mouse in there! This is probably my all time favorite carb but I caution people that it is way too much fun (and perhaps addictive) to kick the gas pedal and your economy goes right out the tail pipe!

Regards,
Glenn

Glenn and Richard are dead on......DO NOT ATTEMPT TO CHANGE CFM or tame a carb down by disrupting the air to fuel ratio. Air is air. It needs the proper amount of fuel to be correct regardless of the size rating of the carb.

I'm gonna put the whole thing together and run a DynoSim on it, but I'm waiting for a reply from Northern Auto Parts to tell me what the compression height of their Sterling (Federal Mogul???) part #235NP pistons is. Not that you're going to change pistons, but while I'm doing it, I want to start a new thread on a cheapo 307 build using 283 pistons and 400 rods. 307 pistons are hard to find anymore, but there are still 283 pistons available from several sources and they'll work with the 5.565" rods in a 307. I just need to get the compression height nailed down so I know what to say in the thread about block deck height and gasket thickness. If anyone knows this CH info, please post it. I want to use a flat-top piston so I can create a good squish. I hate those fosdick stock Chevy pistons with the hollowed-out crowns.

For now, I will say that the 305 heads look like a good bet for a budget build. I found some information on the 416 heads while surfing and will pass it on. Chambers are 58cc's, valves are 1.84"/1.50" and stock flow numbers are as follows:
0.050" 31 15
0.100 63 37
0.150 92 61
0.200 116 78
0.250 134 92
0.300 157 101
0.350 170 105
0.400 182 107
0.450 189 109
0.500 195 110
The 601 heads may be close to the same. I don't know since I found no flow figures on them.

Having looked at flow numbers on a multitude of different cylinder heads until I'm blue in the face, I would say that these numbers look very realistic. I'll use them on the DynoSim pull.

It has been said that these are thin wall castings, so you probably don't want to go nuts hogging them out or cutting for larger valves if you don't have to. Personally, I agree with the idea that the bowl and valve seat area are where the choke points are in any cylinder head, so maybe a little work in there with cartridge rolls to smooth things out a little and call it good would be the order of the day. I wouldn't try to do any port matching at the manifold/head intersection. You'll end up with a cross-section view that looks like an Anaconda swallowed a pig. The increased volume at that point will slow flow down and may result in fuel falling out of suspension. A real good professional 5-angle valve job with a 3-angle back cut on the valves would probably be worth its weight in gold.

Standard Abrasives has a nice little porting kit that can be used by a home hobbyist to clean up the bowls and chambers. Ideally, an air-powered or electric-powered die grinder would be used with these, but in the old days, I used a 1/4" or 3/8" drill motor to do it. It just takes longer and you have to let the drill motor cool down between grinding sessions. Standard Abrasives also sells individual cartridge rolls and such if you can't spring for the $52 price tag on the kit.
http://standardabrasives.carshopinc....d/52221/260001

If you find that you have to replace many valves in the boneyard heads, you might consider buying a complete set of valves with reduced stem diameter in the bowl area. They'll help the flow figures a little.

And again, if any of you fellow or gals can help me find some readily available pistons for cheap, I'd appreciate you sharing the source. What I need is 283 flat-top pistons, 3.875" diameter with oversizes available up to 0.060" and a compression height in the area of 1.795" to 1.805". Northern Auto Parts has them in the part #235NP for $12.95 each, but I don't know the compression height yet. Thanks, Richard.

Denny, I have a lot of respect for your knowledge and will not ever argue with you again. I might end up clutching my chest and falling onto the keyboard!!!!:eek::LOL:

Suffice to say that you have your beliefs and I have mine. :) That's why there are over 400 different religions on this rock, because not everyone believes the same. Peace brother. :)

Tech,

I look forward to seeing the thread.

Quote:

---

Originally Posted by techinspector1

Depends on what duty you have planned for the motor. A rule of thumb for a street/strip motor is to use heads with intake runner size at 1/2 cubic inches. 307 cubic inches X 1/2 equals choosing a runner size of 153.5 cc's. Moving up to the first commercially available aluminum cylinder head, if I were tasked with choosing heads for you, I'd choose the Edelbrock #60879 fully assembled units. These heads have the early manifold bolt pattern so you can use any of the standard early Gen I manifolds, although you'll have to use centerbolt valve covers. The small 165cc intake runners and 60cc chambers will be an excellent match for a "stroked 283" motor such as the 307. Springs are rated for max valve lift of 0.575", so you can run just about any cam you want to with them, within reason.

Cutting the block decks for 9.000" block deck height, using an Edelbrock #7310 head gasket and flat top pistons with a 1.675" compression height will put the static compression ratio at 9.74:1 and the squish at 0.038". I'd choose a cam with duration around 225-230 degrees at 0.050" tappet lift and use a 2800-3000 stall converter.

If you want, I'll put all the info into my DynoSim and choose a cam that will be tailored to your application. You may have to change the rear gear though, you can't run this compression ratio and a bigger cam using a stock 2.73 rear gear (for instance).

If I were not going to go to the trouble of building the motor and just wanted some aluminum heads on it, I might choose an Edelbrock with a larger chamber (64cc's), even though the runners would be larger and port velocity would be down some over the 60879 heads.

---

Please run the DynoSim and see what you get.

Quote:

---

Originally Posted by gte436e

Please run the DynoSim and see what you get.

---

Can you post a photo of the piston crowns in the 307? And can you measure how far down in the bore the pistons are at TDC?

I can't yet, I don't have it broke down yet, or even out of the truck for that matter.

Does anyone know if casting #14102187 will fit on a 307?

14102187 is listed as a cylinder head that fits a 1987 thru 1999 305 engine. It has 55cc chambers and 1.84/1.50 valves (yes 1.84 not 1.94). The useage is listed as boat/car/truck so it was a general use head casting.

mike in tucson