[TMessick]

OK, I need to vent.

Weather in Michigan is finally above 0 degF, so I got around to pulling the heads off my Camaro ('69 307). I knew the original owner had "hardened valve seats installed" at some time back and that the heads that were on there were no longer the originals, but when I had first checked (back in the days before the internet) I couldn't ID what they were. Well apparently, I had some rare heads on there -- 471513. Limited production 79-81 267 V8 heads. Cute little 1.72" intake and 1.38" exhaust valves. Haven't CC'd the chambers to sort out how bad my compression ratio was. I'm thinking this is why the car completely fell on it's face at about 4000 RPM or so even with the 4bbl and "performer" cam.

Cyl's are in "OK" (not too bad, not too good) shape so I'm still debating if I want to slap on some 305 HO heads and slap it back together or spend a bit more $ getting the short block freshened up. Plan is to eventually do a 383, but I'd need to swap the trans (3.42 ST10) and rear (8.2) to handle the torque and $ isn't that free-flowing right now. I'm also a bit curious to see how the 307 runs with decent heads since I alread spent the $ on the carb, intake, and cam (carb and intake will go on the 383 eventually and the cam was la summit special for like $70). The idea is to put a little bit of fun in the 307 and upgrade the trans/rear over the next couple of years in prep for the "real" motor.

Anyone want a set of ultra-rare no performance heads? At least I know the 416's should give me a good bump...

 

[pdq67]

You need to hunt up a good pair of medium valve double-hump heads and go!!

Add one Performer cam, the 204/214 jobber from Summit while you are at it....... Unless your new cam is a mild one like it???

pdq67

PS., and use the .015"/.017" /020" thick shim headgaskets too!

 

[oger]

The 305HO heads should work just fine. I always used 283 Power Pack heads but they need too much work for unleaded gas. You may actually be suprised how well the thing runs.

 

[DenRS]

If price isn't an issue, try the trickflow 175 cc heads with 56cc chambers. Not sure if you want to spend that kind of money on the 307, but I'm sure it would definitely wake it up with these heads.

http://store.summitracing.com/partd...rt=TFS-30300001&N=700+311478+115&autoview=sku

 

[TMessick]

Thanks for the happy thoughts. I currently have a set of 416 heads off a 305 H.O. trans am sitting at my parents place back east. Also have the summit 204/214 cam, edelbrock perf. RPM manifold and 600CFM carb, and (just picked up) a set of thorley tri-y's. Since the carb, manifold, and headers will all transfer to the "next" engine, I considered them an investment in the future. Originally planned to just slap on the 416 heads to "wake up" the 307, but now that I have the engine torn down to the block, I'm debating replacing it (I'm partial to a 327 at the moment) or trying to refresh it with new rings and a backyard hone job.

I keep waffling back and forth for the long-term plans. I go from "I want a 383, torque rocks" to "I want a 327 with a solid lifter because high-RPM power is FUN". Unfortunately, I really don't trust my trans behind a 383 (probably OK with a 327?) and I don't want to spend the $ to do engine and trans at the same time right now. So my choices are:
-- slap the 416 heads on the 307 as-is and drive it till it dies (cheap)
-- slap on the 416 heads and re-ring the 307 (yeah, it's a band-aid)
-- replace 307 with 327 short block. Use 416 heads for now, upgrade later (?)

Planning on trying to borrow the tools to measure my bores and see how bad they are and see if it's even worth trying to re-ring. (engine has ~95k I'm assuming the rings are pretty beat but not sure if it'd be worth re-ringing). Also trying to price out what it would cost to have a decent 327 short block built (preference towards hyper pistons, OK with cast 307 crank, big journal, etc.) This may be the best compromise for me..

DenRS -- any thoughts on how those 175cc TF heads would do on a 327? I like the flow numbers from the TF heads, but the "normal" 195cc heads seem a bit too big for a 327 unless you REALLY rev it out.... Just thinking. That's the problem with the SBC, too many damn choices...


For reference, here are some crappy shots at my cyls:
http://i133.photobucket.com/albums/q75/messit/307_cyls/307cyl1_1.jpg
http://i133.photobucket.com/albums/q75/messit/307_cyls/307cyl2_1.jpg
http://i133.photobucket.com/albums/q75/messit/307_cyls/307cyl3_1.jpg
http://i133.photobucket.com/albums/q75/messit/307_cyls/307cyl4_1.jpg
http://i133.photobucket.com/albums/q75/messit/307_cyls/307cyl5_1.jpg
http://i133.photobucket.com/albums/q75/messit/307_cyls/307cyl6_1.jpg
http://i133.photobucket.com/albums/q75/messit/307_cyls/307cyl7_1.jpg
http://i133.photobucket.com/albums/q75/messit/307_cyls/307cyl8_1.jpg

 

[jumpstart]

You could try to find a running 350 at a local yard. Throw your existing goodys on/in that and have some fun. You would then have a 350 block (maybe a never before rebuilt 4-bolt) for later use for a 383. Just my preference for the 350 over the 327. Cubic inches rule on the street. Good luck.

 

[pdq67]

Slap the heads on her and go!!

They may have 1.84"/1.50" valves, hardened seats, 58 cc chambers and 160 cc intake ports...... And I hit your cam right on the head!! You will be fine here so run her, imho....

pdq67

 

[pdq67]

Install the heads and go and use .020" thick shim headgaskets and you should be right at 9.75 to 1 CR..

pdq67

PS., I hit your cam right on the head!! And fwiw, those heads may/should(??) have 1.84"/1.50" valves and hardened seats, 58 cc or so chambers and 160 cc intake ports so will do you fine...

 

[TMessick]

Well, just in case anyone digs this thread up in the future, I CC'd my 416 heads (305 H.O. off of an '81 trans am, 1.84" int, 1.50" exh) as well as the 513 heads I pulled off (originally off of a '79 vintage 267 apparently, 1.72" int, 1.38" exh).

This was all done by leveling the cyl heads on the bench and using a 10cc syringe that I bought at a pet supply store ($3, I'm cheap). Apply 10cc at a time until the port/comb chamber is full with no meniscus...

416's:
Comb Chamber volume, ~58cc
Intake ports (outer) ~158cc
Intake ports (inner) ~150cc
Exhaust ports (outer) ~55cc
Exhaust ports (inner) ?? (heat crossover makes this kind of hard....)


513's:
Comb Chamber volume, ~55cc
Intake ports (outer) ~154cc
Intake ports (inner) ~145cc
Exhaust ports (outer) ~55cc
Exhaust ports (inner) ?? (heat crossover makes this kind of hard....)

Although I'll be the first to admit that my method isn't all that accurate, I was suprised that the 513 heads had such large ports. Based on the comb. chamber shape, these things seem EXACTLY like the '-601 castings, but with the teeny 1.38/1.72 valves....

 

[DenRS]

Tmessik,

I have the 195 but haven't installed them on my 350 yet. Chevy High performance just installed the 175 on the 84 z28 with a 305. The dyno numbers were not that great 211hp at 5150 rpm and 226lb ft at 4400rpm at the wheels. This is with a mild cam 210/216 dur at .050 with .469 in and .484lift with 1.6 rockers. 84 z28 still have emissions to deal with. I'm sure it would make much more hp with a bigger cam on a 307.

Also in the mag there is also a guy running a 355 in a 90's silverado with these heads. He is also using a supercharger and nos. He dyno'd at 511 hp on motor


The flow numbers on the heads are

In Exh
.100 61 53
.200 127 105
.300 180 142
.400 216 160
.500 242 172
.600 242 180

 

[zdld17]

Mortec says :
471513.....79......267/350.