Anyone do any flow testing on 273/318 heads? I picked up some "920" 273 heads for a Stock Eliminator project at a swap meet. I've ordered an assortment of valves to flow test the different shapes to see what works the best.

Some I got from Rock Auto, OEM replacement stuff, some Manley BBM 1.81" exhaust valves that I will cut down to the stock 1.78" size, also Milodon and MP valves in the same size. Ferrea had some 6000 series valves for the 318 sizes. I even found some GM valves with the 3/8" stems and 1.50" for the exhaust. I bought one each of the valves and so far I spent more money on the valves than I did on the heads.

I thought I'd see if anyone found a good valve in case I missed one. I can't go to the smaller stems (11/32", 5/16") in stock.

i am also building up a 273 stock eliminator to run in my 67 cuda. what combo are you going to run?

I haven't looked at the tech sheets for those motors, but on most Mopars, the heads get superceded, so I wouldn't be surprised at all if the "302" 318 heads are legal.

Edit: I just checked the sheet.....looks like 302's are legal.
I don't know if they're any better or not in that application though, but the better chamber might be worth something.

A friend was building a 1966 Dart for SS, then got a deal on a GM SS/GT car and moved to the dark side. He made me a deal on the Dart (the 1967 Barracuda is a better choice with bigger wheelwells in the back). It has a roll cage in it already and the 2800# SS springs. I'm hoping it can be a "dime rocket", but I'm sure it will cost more than a dime and may not be a rocket. Hopefully it will run decent.

The 302 heads are legal. I got the 920 heads cheap at a swap meet, but will buy some 302s if I can get them at a reasonable price. The 340 AVS intake and the Edelbrock LD4B are legal replacements for the flat 4bbl intake. I bought a 273 AFB carb off Terry Dye in MI. The Dart falls at the bottom of K/SA, but will most likely run in L/SA. I paid $50 for the heads and just spent $280 on an assortment of valves to flow test. I went through the Summit site and ordered one of every valve that was a 3/8" stem and around the stock 1.78"/1.50" sizes. Ferrea has some 6000 series valves and they were the most expensive.

I have some max effort 1.88 1.6 valve 302 casting heads from modern cylinder head that flowed around 220 CFM if I remember correctly. He said they were done for some kind of SS class or something, the rocker stands are milled flat, everything is CNC ported chambers and every thing... if someone needs em they should PM me, I bought em for a project that never got done.

Those would be good for a SS engine (318?). The NHRA spec for the 302 and 308 ports are the same for both heads (160cc on the intake if I remember right). They won't be legal for Stock though. I have to stick with the 1.78"/1.50" plus some tolerance (I think it is +.005"/-.015"). NHRA has opened up the valve job to "any valve job". I've tried to get a ruling on that, but nothing. I assume that means up to the guide now. If I could figure out how to do the valve job all the way to the intake face, those heads might be legal for stock.

Don't you still have to have a 45* seat?

No.

And........ Unless you set a record........no one will ever see it anyway.

He had any valve job in quotes. I'd have to see a rule book but I doubted they let stockers use other than factory seat angles.

I'm sure some have done it. Like you say, unless you set a record....

I've had some heads on my flowbench that were built for STOCK class and what they do would surprise most people. I know I was totally shocked.

Last I saw, the wording regarding the valve and seat angles remaining the same as factory had been removed from that paragraph in the rule book.
Now it's just "any valve job accepted".

The "valve angle" has to be stock...... This is the angle of the valve in the head(15deg, etc), not the angle of the seat on the valve.

The bottom line is, they want less stuff to inspect at tech.

There is definitely some ambiguity in that phrase!

From the NHRA Rulebook 2016:

"CYLINDER HEADS
Must be correct casting number for year and horsepower claimed,
per NHRA Technical Bulletins or NHRA accepted. Porting,
polishing, welding, epoxying and acid-porting prohibited.
Combustion-chamber modifications prohibited. Cylinder heads are
additionally restricted in that they must retain original-size valves at
original angles +/- 1 degree and must be able to hold original
cylinder-head volume per NHRA Specifications. Runner volumes
may not exceed the current Super Stock cylinder-head volumes as
listed on www.NHRARacer.com. Regardless of the poured volume
measurement, any modifications to intake or exhaust runners
prohibited. Any evidence of modifications from the original castings
will be grounds for disqualifications as determined by NHRA in
NHRA’s sole and absolute discretion. Any aftermarket steel valve
permitted, must retain stock head and stem diameters. Only
engines OEM-equipped with sodium-filled valves may use sodiumfilled
replacement valves. Titanium prohibited. Hardened keepers
permitted. Lash caps prohibited. Valve-diameter tolerance: +.005-
inch or -.015-inch from NHRA Specs. The following are prohibited:
spark-plug adapters; any grinding in ports or combustion
chambers; removal of any flashings; sandblasting or any other
modification to cylinder head; any film coating of intake and
exhaust runners; any film coating of combustion chamber. Runners
and combustion chamber must retain OEM appearance. Final
acceptance as determined by NHRA in NHRA’s sole and absolute
discretion. External modifications prohibited. Intake side of head
may not be cut into any part of valve cover bolt holes. Valve-cover
bolt holes must remain unaltered and in their original location.
Heat riser passage may be blocked from intake manifold side of
cylinder head. Blocking passage down in valve pocket prohibited.
The following are permitted: polylocks, jam nuts, screw-in largerdiameter
rocker studs or pinned studs, bronze-wall valve guides,
cylinder head studs. Valve spring umbrellas optional. Cylinder
head may have all of the seats replaced. Any valve job
permitted,O-ringing prohibited. Exhaust plates prohibited."

I took the +/-1° to mean the valve angle relative to the deck. Sort of limiting how much you can angle mill the head.

Or race at Indy. Probably will never do either one. I've heard several stockers got torn down at Indy, not just record holders. Some are from a random draw. I guess someone could protest another competitor, but I haven't heard that happening very often. I just want to run fast enough to qualify at the divisionals and the national events near Dallas. Probably need to run at least -.50 under or a bit more.

Seems very clear that the valve job is NOT a tech item any longer

My buddy Mike got a random teardown at a divisional. Sometimes they pick 2 and take a look.

Exactly...... Or trying to put a little "cant" in them by installing the guides not parallel to their original c/l.

The valve job however, is wide open now. Play with as many, or different, angles as your heart desires.

In division one, where there are often 100+ stockers at an event, a .50 under car doesn't get much scrutiny. You'd be in the bottom 1/3 to 1/4 of the field most of the time.

We don't get that many in Division 4. I notice that Fletcher qualifies in the bottom half of the field. Not sure if that is some sort of strategy in the ladder. As long as I qualify, running below the index only counts if I'm running someone in the same class, heads-up then. Otherwise it's pretty much a dial-in bracket race from what I can see.

For the most part, I just want to play and hang out with my other stock and SS friends I've made over the years. It's not like there is any money to be made in it. I toured the Rousch Racing facility in 1998 and the old Trans-Am car was there. I asked the guy about it and he said they got tired of racing for "ashtrays", aka, trophies.

There are definitely qualifying "strategies" being played out in Stock.
Qualifying lower means you would be eligable for the bye in later rounds.

As long as you're fast enough to not worry about getting paired up in a heads up run with someone who's qualified higher than you are, qualifying higher isnt really much of an advantage.
Unless you're hoping to be able to get the bye earlier rather than later.

As an example of division one..... Maple Grove spring race, 113 cars.
.525 under was number 92. My buddy was number 40 with .786 under, and there were 18 cars running .90 under or better.

I looked back at the national event in Ennis. More cars than I thought.

1. Brian Massingill FS/C 10.30 9.132 -1.168
2. Bill Skillman FS/A 9.70 8.558 -1.142
3. Charlie Downing FS/G 11.35 10.250 -1.100
4. Stephen Bell FS/A 9.70 8.617 -1.083
5. Jeff Lopez FS/C 10.30 9.226 -1.074
6. Nick Reiter D/SA 11.55 10.491 -1.059
7. Brandon Bakies G/SA 12.00 10.948 -1.052
8. Thomas Marlow G/SA 12.00 10.959 -1.041
9. Sammy Pizzolato B/SA 11.25 10.211 -1.039
10. Butch Marlow FS/G 11.35 10.315 -1.035
...
46. Patrick Courts L/SA 12.70 11.906 -0.794
...
61. Brenda Grubbs AA/SA 10.70 10.165 -0.535
62. Jeff Teuton E/SA 11.70 11.206 -0.494
63. John Brimer A/SA 11.00 10.526 -0.474
64. Leon Philpot L/SA 12.70 12.228 -0.472
65. Parker Devore I/SA 12.30 11.922 -0.378
66. Bill Bogues H/SA 12.15 11.800 -0.350
67. James Tolston Jr. E/S 11.65 11.317 -0.333
68. Lowell Gerber H/SA 12.15 11.916 -0.234
69. Bill Bailey G/SA 12.00 11.797 -0.203
70. Keith Bakies C/SA 11.40 11.203 -0.197
71. Sharon Bogues J/SA 12.45 12.598 0.148
72. Gerald Nivans W/SA 16.65 27.418 10.768
--------- Not Qualified ---------
73. Dale Hulquist D/SA 11.55 DQ

It looks like two other cars in L/SA. Class winner might take -.80 or so. #1-5 Qualifiers are all the new cars. I heard that the #1 qualifier is a bit of a douche (JK, LOL!).