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Questions-12G295 head.

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Intresting that. Not sure what I actually learned that I could use but intresting for sure.
 
Donn, my error regarding the 202 being nearly a clone of the 295. It's the <u>206</u> that's very close. /bcforum/images/%%GRAEMLIN_URL%%/blush.gif The 202 is indeed, a closed chamber head.
I'm restricted to only three heads that are legal for the 948 in H Production. The 2A629, 12A185, and the 12G202. I had the 202 done because it has the best configuration of the three possibilities. The 12A1456 isn't allowed.
Jeff
 
But those shinny places surely look great in Pics.
 
Yeah, wouldn't it be nice if you could see them when the head is on the car!

Personally for a street car, I'd polish the chambers enough to be mostly smooth and enlarge the ports around the valve guides, rounding the sharp bends nicely, and taper the guides. Then a 1st class 3 angle job with polished valves with correct shaping. Most bang for the minimum buck.

Valve shaping isn't rocket science. Small mods make a big difference, something like this:
Valvemods1.jpg
 
racingenglishcars said:
(And shiny combustion chambers don't increase performance)
(worth noting.)
Click to expand...

No, but polishing is the best way to equalize the chamber volume, when you get down to the final gnats whisker.
I'm not having any luck finding the flow bench data from that 202, but I'll keep looking. They're pretty decent numbers.
I just wish I could legally run a 295.
Jeff
 
Now we talking. For some reason that all makes sense. To me that would be best done on a lathe? yes, no. How is that done certinaly not free hand with a grinder.
 
Interesting! I use an intake and exhaust valve in the race car that is round; no three-cut, no rim flow--round. Perfect seats all the time. I am usng Chevy valves, too. 1955 Healey Hundred.
 
JPSmit said:
jlaird said:
Roger that Hap.

Hay I figured out what to tell the shop guy.

"Hi Hap, here is the head I need worked"
Click to expand...

Good call - BTW saw in Classic MotorSports that Hap is going to be speaking in Florida in January at the British Motor Trade Association in St Pete's

Congrats Hap!
Click to expand...

I won't be in Florida at the BMTA, I'm too busy to take a few days off, they just mentioned I had attended in the past, but David Anton, Joe Curto, John Twist and others will be there, so it's a good deal to attend and get to pick these guy's mind. Between going to the race track with customers, and taking extra time to be a British car club president, attending the BMTA for me this year isn't a reality.
 
Well, I read Vizard...& read Vizard...& read Vizard

& then I decided to build my engine back stock!
 
And now you know the rest of the story. Some story isn't it.
 
Everytime I read that book I wish I'd gotten an engineering degree!
 
racingenglishcars said:
With all the work repairing a 295 head, one could just as well start off with a bare head and buy all new guides, valves and springs. there's one on evilbay here right now only $6.50, in PA.
Click to expand...

And the max bid is quite a bit higher than $6.50 -- ask me how I know... /bcforum/images/%%GRAEMLIN_URL%%/thirsty.gif

Tim
 
tony barnhill said:
Well, I read Vizard...& read Vizard...& read Vizard

& then I decided to build my engine back stock!
Click to expand...

Tony, I was waiting for that! I feel I can say so because I've felt much the same way at times. Then its usually Jeff to the rescue! /bcforum/images/%%GRAEMLIN_URL%%/cowboy.gif

Oh yeah, I've a street version out in the garage someplace too. /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif

Tim
 
I have now seen them go for $50 to $300. No telling who wants what.
 
Head arrived today, nice indeedee.

Looks like it has been skimed a bit to 2.729 from stock 2.750 and has been ported and releaved but not polished.

May have new valve guides, more looking required.

Even had a bunch of dead bugs in one of the exhaust ports.
 
How does one differentiate the various heads that are out there...are there number-stampings somewhere? (Just for future referrence) I have 3 engines (non of which have been apart yet!) and was wondering when I get into them how to identify what I've got! Can I just go by engine #,but what if a head has been replaced?
 
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