Should I keep these heads?

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66 Barracuda

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I'm building a 77 360 for my 66 Barracuda. Block .020 over, new cast crank, KB 107 pistons, 72 340 high-po exhaust manifolds, holly 750, (not sure of the cam) I guess the question is, are these heads worth rebuilding with 2.00 intake valves for this application, the exhaust ports of the heads are considerably smaller than th hi-po manifolds. Or am I waisting time-money-effort!!!!!!!!!!!!
Do I need something with a less cc chamber.
 
If the seats are beat, I'd run 2.02 intakes and 1.65 exhausts, have unleaded seats stuck in, the guides trimmed and spring seats cut, and have the chambers reduced to 68cc. They'll be fine.
 
Good Idea, would probably save a ton of money. But wouldn't a 77 already have hardened seats? Also, if you mill the head, does the intake still line up and seat properly? I'v never milled a head.
 
Hummmmmm, I thought I answered this question earlier. Is this posted somewhere else?
 
What if I crammed a KB 190 piston in there with Quench dome height .050".
 
Why? You do want to run pump gas right? If so, stick with the lower ratio pistons.
 
I only ask because Kieth Black advertises them at 10.5 : 1 with a 72 cc head.
 
Can run pump on 10.5-1?

How big is the cam? Or what one will you run?
 
Sorry Haven't gotton that far yet. Just trying to learn as much as possible from you guys so I get it right the first time. Want to have fun street and strip.
 
OH, the 77's should have hardened seat, yes!

Ummmmm, are headers oput of the question?

Street strip fun? OK, umm, how fast in the 1/4? Or just a basic street brute.

What tranny and what rear gear do you have and want to run?
 
Ok, hear we go.
77 360
3.58 stock cast crank
TCI 904 tranny with 2500 stall
8 3/4 rear end with 355 gears
225-60-15 tires in rear
old torqer 340 intake single plane
Probably holley 750

This is a 66 Barracuda. Refuse to cut on car. So I'm going with 72 340
hi-po exhaust manifolds.

Looking for at least 13 on the quarter.

This is why im searching for head help.
Thanks.
 
I don't think you'll have to cut up the cars metal in order to install headers. True, there are some model headers that would require that, but there are more that do not require it.

Best of the bunch are ethier Dougs or TTI headers. Both expensive but worth it.

Stick with a zero deck piston. I'm not sure what cam would do the trick for 13's. I'll have to do some figurin before I suggest a cam.
 
So if I stick with the zero deck piston, even with a 72 cc head, wouldn't I still be somewhere around 9.5 or 9.8 to 1 on compression? At least that's what Keith Black is advertising. Which would be good.
 
Yes, I've run this combo before. 9.8-1
I *think* the comp cams XE268 would do the job.
Or the 268AH-10 which is a 340 cam from com or the MP 340 cam upgrade is also in the same ball park.
 
My un-blown combination wasn't very far from the one he's using.

My car is (look to the left) a '72 4-door; probably 250 pounds heavier than the Barracuda he's building; there's .25-sec right there....

My engine's specs...

360 Magnum stock short block
Stock Magnum heads with a bowl port only 9:1 true compression; stock, dished pistons
Early 340 cast iron exhaust manifolds with a complete TTI 2.5" system (H-pipe), Dyno-Max Super Turbos
Low-performance (water heated!) aluminum 180-degree M-P intake with an out of the box, 3310 Holley (750 vacuum secondary). Stock jetting all the way.
Windage tray
Stock-type, curved M-P distributor and an Orange Box.
Hughesperformance cam.... VERY mild! Only 214/218 @ .050, but with lots of lift (.525") Ground with 114-degree lobe separation. Idles at 475 in gear, with 14 inches of vacuum.
Good to 6,500 rpm, but stops pulling hard at about 5,600.

904 with a Trans-Go shift kit and a stock 318 converter; 2,500 rpm stall (lots of low-end torque with that cam!) Stock 2.45 first gear ratio.

The cam is a reground Magnum hydraulic roller using 300# springs, heavy duty pushrods and Crane roller aluminum rockers. All from Hughes...

8.75" 'unlocked' rear (no sure grip) 3.91:1 ratio with 8"-wide BF Goodrich T/A Drag Radials (J-U-N-K.... stay away), with stock springs and an air bag on the right rear.

The bottom line:

On a 95 degree day at sea level (Sacramento, CA) it ran a best of 13.35 @ 102 mph, with a best 60-foot of 1.91. I had to leave at 1,200 rpm... no bite. Driver wt. 250... :angry7:

My Magnum heads might be marginally better than 360 L-A heads (just a guess; I don't know that for a fact), and my roller cam is probably more aggressive on the lift than a flat tappet, but his 250 pound early 'Cuda weight advantage over my '72 4-door sedan probably cancels all of that out.

My advice is to call Hughes and tell him what you want (ask for Dave), in the cam department. They only do Mopar stuff, and they're very good at what they do.

Good luck; I think 13's will be easy for you.
 
Great post Bill. Let me ask you about his ride, what do you think he'll run with the small differences in cars and gear?
3.55's vs the 3.91 and weight dif?
13.70's?
 
Thanks for the kind words, Rob.

I'm thinking it will depend somewhat on the cam he uses. I'd try to stay somewhere around 225/230 degrees @ .050" (with about .480" gross lift,) for driveability's sake since this is not JUST a race car. Street manners are important, and with a 3.55, you can't get very wild with duration or your daily driver experience will be a little disappointing, I would think.

I don't have ANY affilliation with Hughes (don't even know the guy), but every time I call there for advice, he always takes his time explaining why he recommends whatever he does.... never in too much of a a hurry to talk about specifics; that's why I'll give him my bidness the next time I need a cam.

It doesn't hurt that MOPARS are all he does... unlike Comp Cams, which is also good, but basically a Chevy outfit.

I think that if he gets a moderate cam, but one with a couple of steps more duration than mine, that 13.50s would be like falling out of a tree for that car.

Just my .02.....

Bill
 
IMO, you will need a lower static to run any cam under 220°.050.... otherwise you have a tendency to detonate. I would go larger on the cam to run the higher static... because it makes more power overall, and doesnt lose drivability. The XE268, and Lunati 268 grinds are on the hairy edge of not big enough. but I'd rather have more power and performance all accross the range, than go lower to run a very mild cam. Just builder's choice there...lol. As far as hughes, ask 10 guys, and you'll find at least 4 that hate them for various reasons. I think they are ok, but very attitudy and god forbid you have a different idea. They answer questions. The matter is not open for debate...lol
 
I'm confused. Do the 77 360 heads have the small exhaust port like a 318? You said there was a big differance between your 340 manifolds and the head's port. What are the numbers on your heads?
 
Moper.

I detected some of that "not open for discussion" attitude, but since I was the one asking, and I'm just a hobby racer (and he's "in the business"), I never argued with him.

My cam turned out well... it was exactly what I needed, but I degree my cams when I install them and the one I ended up with was the THIRD one he sent me; the other two were not ground correctly.... they either had too little gross lift, or the event specs were inconsistent with the card. Not bad enough to make it run "funny," probably, but didn't match the card.

He gladly replaced the first two (probably after seeing that I was right, after he got them back.)

Ultimately, he told me to degree it in, not by any other spec than making sure the intake valve closed exactly where the cam card said it should. I did that, and it has 195 pounds of cranking compression with a true 9:1 c.r.

But, in order to get it to close there, I had to advance it 4 degrees.

Now, I have TOO MUCH low-end torque (blows the tires off leaving from an idle), so the next time I have the front end off the motor, I'm going to take that advance out of it and try running it "straight up." I think it will destroy some of that excessive low-end, and maybe pick up a little on the top.

Anyway, Dave Hughes dictated every part in my valve train (what to buy) and not a single item has proved problematic... so far. Of course, I have a 6,000 rpm street engine with hydraulic rollers... what could possibly go wrong??? LOL! But, it DOES go 106 in 1,000-feet.... :sign10: Fast enough for an old man....

I'd buy from Hughes again... Guess I'm one of the six out of ten... LOL!
 
Bill, yup. I own a hughes cam... never ran it, but I did buy one...lol. I am surprised to hear the gringing issue tho. Honestly, aside from the lack of newer lobes, I stopped running MP for the same reason. They were ground terribly.. Like Gump's box of chocolates... I never knew what I was gonna get... AS long as the customer is happy, it really doesnt matter.
 
bobscuda67 said:
I'm confused. Do the 77 360 heads have the small exhaust port like a 318? You said there was a big differance between your 340 manifolds and the head's port. What are the numbers on your heads?
Click to expand...

No Bob. The 340 & 360 have the same sized intake & exhaust ports which are larger than the 318's. The exhaust manifolds have a bigger port window. Why? I don't know.
 
The driver's side 340 hi-po exhaust manifold will not fit your 66 Barracuda. Headers are your best option. TTI, Doug's, Layson's or Spitfire make under chassis headers for your car.
 
Bill Dedman said:
On a 95 degree day at sea level (Sacramento, CA) it ran a best of 13.35 @ 102 mph, with a best 60-foot of 1.91. I had to leave at 1,200 rpm... no bite. Driver wt. 250... :angry7:
Click to expand...

They don't call it the Sacramento Slickway for nothing!

As far as compression goes, I wouldn't go over 10:1 for pump gas with the iron heads. Not sure what you can get in Washington, but with our 91 octane in CA 10:1 is definitely the top end.
 
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