cast iron heads vs aluminum for stroked 340

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buzzmc

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Seems this question sort of gets answered and sort of not, or I haven't found the magic words to search for that comes up with an answer.

The intent - Build a stroker for the street, pretty beefy but still streetable. So it'll be a dual plane manifold (likely air-gap) deal.

To be honest, I'd prefer to "get away with" using hydraulic cam/lifters, and I'm wanting to use X or J heads as well.

It'll go to the strip every once in a while with friends, for fun. It's not a drag car.

All that said, I'm hoping to get in the mid 550's HP/TQ, which seems doable with all the right parts.

So - the question in the subject above... Can you tune up cast iron heads to work with this sort of combo... or if I'm really to hit the numbers I want, for the engine to breathe, am I going to need to part with some significant money for better heads?

While I'm asking questions, what's the deal with closed vs open?

Thanks!
 
You're going to have to part with some significant money for someone to port iron heads to that level or buy aluminum heads and have them ported.
 
550 hp/tq is a lot on the street. Have you had another car with a motor that has 550 hp/tq dyno sheet to back it up?

Without drag radials you'll have much more motor than tires.

An honest true 550 hp/tq 4" stroker is going to be on the raunchier side of things to fart around town and pick up groceries and take the kids to soccer in. It will be "beefy" and then some.

It's going to take ported J heads. And ported Edelbrocks too. To keep the cam streetable and still make the hp/tq.

Not sure 550 hp/tq and hydraulic cam go together. You'll still need good adjustable rockers at that lift. Probably aren't going to get enough engine vacuum to run power brakes and accessories.
 
autox - agreed... I guess beefy could be translated into beastly or nasty.

And the car has no vacuum accessories at all. It's caged, most things are not in it anymore, etc.

It's actually a 66 valiant signet, which was a pain the you know what to fit a SB into to begin with. It was originally a 225.

No frills, big HP/TQ, and maybe very accurately "unreasonably streetable". No turbo's or blowers either. Definitely looking for the under-stated wow factor...
 
Is it tubbed or mini tubbed to go along with the cage?

Can't fit much tire into a stock 66 Valiant.
 
I would think exhaust constraints with that chassis will limit your power unless you go fender well headers?
 
tti finally makes a-body headers.... but I had some custom made 15 years ago. Exhaust has been nuts before though. Actually, when I found out they had headers specifically for 63-66's I was over the top happy... as anyone "in the know" can understand.

Car's not tubbed. I'm not expecting significant traction adn therefore lower et's. Likely will buy a different set of wheels/tires solely for the track. Otherwise not overly concerned, though after it's built and done I expect I might change my mind on that front.
 
If you are looking for a cast iron stock "look", a set of prepped W2's will for sure support 550 hp.

Of course your current header flanges will not have port matchup. Econo W2's have stock exhaust bolt pattern, IIRC.
 
W2's are no good because of the exhaust differences, as you indicated.

So back to the topic.. Can X/J heads flow enough after being ported to support a mid 550hp/tq build... or is it just not going to happen?
 
buzzmc said:
W2's are no good because of the exhaust differences, as you indicated.

So back to the topic.. Can X/J heads flow enough after being ported to support a mid 550hp/tq build... or is it just not going to happen?
Click to expand...

Like IQ52 said, if you throw enough money (and cam) at them you could reach that number.

I would guess the F.A.S.T guys and NHRA stock class guys have heads that would get to that number. A 4.25 stroke thrown into a meaty 340 block would go a long ways.

Also, you could have someone with a real "happy" dyno get whatever numbers you want. Horsepower on paper at the flick of the wrist. :evil3:
 
buzzmc said:
W2's are no good because of the exhaust differences, as you indicated.

So back to the topic.. Can X/J heads flow enough after being ported to support a mid 550hp/tq build... or is it just not going to happen?
Click to expand...

Oh the heads can do it, but your hydraulic cam isn't going to.

Here are J heads flows we got on a set from about 10 years ago.

Lift.............Intake only........lost the exhaust flows

.100..............78 cfm
.200............139
.300............187
.400............232
.500............270
.600............292
.700............298

Then getting the rocker arms to work on these J heads, that's fun at those lifts!

Ported Indy 360X iron heads..........

Lift.............IN/EXH

.100...........78/69
.200..........147/137
.300..........203/191
.400..........241/235
.500..........275/267
.600..........296/286
.700..........306/294

Ported RaceMaster/ProComp aluminum heads

Lift..............Intake

.100..............69 cfm
.200.............139
.300.............195
.400.............240
.500.............271
.600.............300
.700.............297

These heads are on a 426 ci small block that is making 500 lb-ft of torque 4,200-6,300 rpm, 561 lb-ft of torque @ 4,900 rpm and 554 HP @ 5,400 rpm.......and.........well.......601 HP @ 6300 rpm. That is using a custom solid roller (over 250 degrees @ .050") that drives around on the street very nicely with 3.23 gears and an automatic transmission.
 
I'm not after happy numbers.

It's probably pretty good indication with the builds that I have found and can read about that it's probaby not possible.

Most builds favor ported Eddy's and solid cams. I discount the single plane manifold folks running 7k+ rpm's because that's not what I want at all.

The only other build I've seen with cast iron heads was a 600HP build, but it was on racing fuel with very high compression - Also not happening.

I understand all the pieces need to match up, and that really cam and airflow are the biggest issues it would seem for me - or anyone wanting to build a potent stroked SB... I was just hoping that there might be some evidence / wisom out there that you could get the airflow from some well ported X/J heads (I happen to have 3 pairs of heads with 2.02 intakes and adjustable rockers.... I should probably just sell some to finance the Eddy's).
 
It's not that the goal build is unrealistic but it is a odd one. Like mentioned, Mike at MRL has interesting engines that should be looked into.

Otherwise, the only iron head(s) worth looking at are the Indy or the more capable W2.
For aluminum, well done Edelbrocks will turn some numbers. There's also Brodix. B1BA-MC.
W5's are a crap shot. Only worth IF the can be ported out to what you need.
 
Indy x heads will be a whole lot cheaper than porting out J or X heads plus they will have a close chamber for a nice quench build. The hydrolic cam is probably not the best idea, a good FT solid in the .250 @.050 area with a total lift of just about 575 to 590 using 1.6 rockers will work nice with the indy RHS X heads.
 
a mild 418 (425 hp) will have a ton of torque and should break traction in any of the first three gears at will.
..a tremendous street engine,
..how did you arrive at 550 hp?
 
550? Easy answer, why not?

Honestly, when I started reading/researching, mid 500's seems very doable wiht a stroked small block and still keeping it reasonably drivable... So that's why. You don't need to run a single plane manifold and turn 7500rpm to get there. Everything has to add up and match up well from the ground up... Which is what prompted the question about heads.

I've gotten enough helpful info from a few different people that lead me to believe well worked X/J heads will work just fine... Which is good since I already have them anyway. Add stroker kit, match up a cam and a carb, go have fun... THat's the plan.

If I wanted to get really sneaky I suppose I could hide the MSD and remove the MPerf valve covers with stock, and anyone looking at the motor in the future would be scratching their head wondering what the hell was going on in there :) ... That's also the plan.
 
You'll get there a lot easier with Edelbrocks and shave 50+ lbs off the frontend..my 416 made 520 h.p. with a set that were mildly ported..running a set on my 360 now seeing the results i will never use steel heads again,got a set collecting dust in the garage now:D:D
 
Hide the MSD under the battery box.

I'm with stroked340!

And speaking of which, what heads do you have? Stockers? I have 3 set collecting dust myself..... LMAO!
 
I've been involed in a few 4" engines that cleared 550hp N/A. If you want to use iron, sure, you can do it. to be honest I've never, ever, ever seen iron X/J/O/whatever heads that went 300cfm, or that gave the results that indicated that ability. Even with tubing the pushrod holes and making them bigger. But, to make 550 you don't need that much. There are other ways to skin a cat. If you can't make it via airflow at lower rpm, you can make it via more power strokes per minute with less air. You need a real 250cfm at .600, and a cam large enough to make full use of it and get some serious rpm. So can you? Yes, you can. But you'll be porting the hell out of them, modifying the rocker setup to run blocks and Jesel rockers, and you'll need to spin it to 7K+. You won't do it at all with a hydraulic cam. Maybe a flat tappet solid, but more likely a solid roller. If you want to be more reasonable in terms of reaching a goal, rather than trying to hobble yourself beacuse it looks cool, then go with either the Indys or RPMs with full porting. I'm still not 100% behind the lower price point heads but they might be able to do it too. If you get an honest 300cfm from anything at .600, you can make 550 with the right camshaft. But I still don;t thin that cam will be a hydraulic.
 
Agreed, won't be a hydraulic cam. Was hoping for that too, but that's not in the cards. And that's ok.

Only way it works is for it all to work together, and that's part of the equation.

I won't build a car to spin 7.5k, want nothing to do with a single plane manifold, and building power from 4500+ isn't what I think of as streetable. If I did that I'd tub it, trailer it, and take it to the strip.
 
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