wow this a really old thread I sold a new set of bowtie 2 heads that were bare I bought many years ago but never used them to the poster on here L holms.

 

What kind of $ are those going for?
x2 on cracking....they can be ported, not crazy #s but decent. (potential)

 

No clue. I got rid of them because of old antique combustion chambers. That and without porting they did not flow all that good not a whole lot more then across the assembly line heads of 1960s. I'm thinking I bought them new around 1984 just never got rid of them for many years.

 

Old thread, and the internet has lost carnal knowledge on a lot of this stuff, so I don’t mind putting something up on a lost generation of performance parts.

I still have all of these heads, as that was my generation!

You can get decent performance still out of like Bowtie Phase 6s. I am up in the 500+ hp range with Small Blocks. These are still the highest hp potential traditional 23 degree units!

You have to change the guides on some of these, don’t get the ports too thin. The spring diameter needs to be checked, as they were changing during this era! The Bowtie mostly stepped up to 1.55 pockets allowing duals more easily! I was liking the 1.379 duals, but finding a steel retainer is difficult now, that is perfect sized for that GM unit! Great compact spring for older heads! The old Double humps could be machined to step up!

If I wasn’t using GM Bowties, I like Brodix like Track 1s. I have some old stuff like Brownfields, and some ported units from Traco’s favorite porting guy Letterman

All of the Iron Phase 2 bowties can be taken out to flow around 275-290 cfms. Phase 6 aluminums, 280 is a great max number, some more talented could maybe get 5 -10 cfms more, but you will be thin. Stopping at about 270-275 is reliability! You can widen the ports on the bare undrilled units, but that requires exotic offset rockers!

 

If you really look at the Chambers they were already starting to make improvements there. The angle plug locations helped flame travel with domed pistons.
I never noticed the port areas being thin but most of the heads I ported needed about 3 containers of bars leak to seal up the water. But that was pretty common. They aren't the best or close to it today but it was a start back then.
Whenever I hear a die grinder I can taste the cast iron lol.

 

Black boogers lol
Porting cast iron takes a lot of patience. 270-280 is a good # for a sb head. in this day and age its easy to say "less than 300 is a pos". Not so
Anyone notice the tfs double humps have the same old school type chamber ( or close anyways)
TC Id sure love to takea walk through your garage and see all that good stuff. In teh 80s worked at a dealership thier parts catalog had all the good stuff. knew back then I ought to stock up but was young/broke!
Now Im older and broken down

 

I bought a ton of it, and then got broken! .

I threw some random parts pictures up in that Guldstrand rare parts thread near the end, just a month or so again. Have some Bowtie stuff shown. At 300 Cfms, I equate the build to a 600hp engine. Generally if you are cammed and built right, you should be able to get double in HP to the Cylinder head intake flow. Yes a 600hp small block isn't so hard to do anymore, following the pioneering guys that came before us all.

 

600 is doable but gets tough and keep it driveable
500 mid 4xx-500 is too tough, geting above that usually means cubic $ and sacrificing something.

Below is an example of a simple 11 sec car doubt its 500chp
12.5:1 350
pink rods
Ported bowtie/turbo heads
Holley strip dominator 850 holley
Used to DD it on the 405 fwy when 55mph speed limit was around
4.56 gear, converter. never been apart since the 80s runs like stink. Very reliable

 

It's an old thread but has info of value ...

... see the pic https://cimg2.ibsrv.net/gimg/www.cor...31978fac68.jpg

... see the exhaust valves (smaller) ... see the faint blue outline around exhaust seats ...
... that's telltale evidence of the hardening process of the exhaust seats ... these are probably done via electric induction coil ... but perhaps via flame.

Anyway, for those who didn't know, that's what seat hardening looks like.

 

One thing I see, is a lot of overkill. You can have the baddest set of heads on the baddest *** engine, but if they are too much, it is worthless essentially. 2.20 valves have supported stock mills, and heavily ported runners. If you want to throw away any street driveability, then put 600 hp head and a cam into your build and 2.10 valves in your small block. Bad ***! isn't always the fastest!