What is the horsepower potential of this head on a .030 over 440? Given max effort cam and intake selection using Flat top pistons, roughly 11.5 to 1 compression.

700+ hp with a drag race type solid roller cam. You'll need the matching parts of course. Ported intake, really good carb, correct valve train parts, correct size headers, good oil pan, etc.

Most street/strip guys pick parts that give them 600 hp with those heads and compression, but you can add another 100 hp if you know which parts to use.

It’ll be easier to get there with 270’s.

Thanks for the replies, I'm trying to decide on what would be the best approach to reducing my ET. I want to run a 10.50 index class and I am now consistently running 10.70's. Was considering a cylinder head swap from 240 to the 270 head but a cam change may get me there if 650 hp is doable with the 240 head. My current cam is a flat tappet 254 int and 260 exh @ .050. Looks like I would need about a 40 hp increase to get me there.

What size carb are you running now?

A 1000 cfm pro systems 4150

Would need a little more information before I could provide specific advice. Car details, engine details, etc.

If you're making 600 hp today then it should be possible to increase the engine to 700 hp with a well matched solid roller. You'll need a really good intake to hit 700 hp. Good intakes are hard to find for the standard port heads so you'll most likely need to have an intake ported which could cost $1000 just for the porting. You'll also need a set of good 2 inch headers and the oiling system needs to be correct for that much power.

It is probably cheaper to swap over to a set of 270 heads since then you can buy a better intake. Sell the 240 heads and 4150 carb and intake and buy a set of 270 heads with the good roller springs. Then get a solid roller in the 260/270 range (talk to Dwayne), a good intake and a 1050 Dominator. If you get decent prices for your existing parts you won't be out a ton of money. Especially if you can buy the intake and carb used.

How many runs on the short block ? What’s in it ?
Have you thought about adding a stroker kit and using the top end you have ?

So my thinking or wondering is, how much horsepower is left in the cylinder heads? What is the most cost effective way to get where I want to be? Perhaps I should have opened the thread with that question.
The combination is a 3700 lbs. with me in it.72 charger. 4.30 gears . 30x9 slick .5200 flash stall converter, footbrake car. The engine is a .030 over 440 with flat top pistons, total seal gapless top rings. 11.7 to 1 compression..ootb 240 heads
deep port match trick flow intake by Hughes engines. 1.6 rockers. a 1000 cfm pro systems calibrated carb. A Hughes engines flat tappet cam 254 int,260 exh @ .050 . 640 lift int 656 exh. My best et in very good weather is a10.57 @ 127mph. avg et is 10.73 @125. The engine has 110 runs on it. I'm a lot closer to 10.5 index than the 11.5 index. Can I get 40 hp with a cam change?

Talk to fast68plymouth and AndyF. They’ll get you there.
Nice car !

127 mph @ 3700 lbs puts you right around 600 hp which is what I'd expect from those parts.

If you have good headers and a good oiling system then an upgrade to a solid roller will pick up some power. Fully porting the intake will pick up power too but it is expensive. I used a fully ported M1 4500 on my pump gas 470 and we made over 700 hp but it was a very expensive intake. Probably cost $2000 to duplicate it these days since it was cut open and then welded back together. There are more choices for an RB intake. Maybe the std port version of the Super Victor for example. Sticking with the 4150 carb will cost you some power. Are you willing to put a scoop on the car? Do you have fresh air to the carb?

The cam I used was a custom 264/268 that Dwayne had ground. That same cam should work for you or he might have something that would work even better. You will probably need a looser converter to keep the engine in the power band all the way down the track. Something in the low 6000 range for the shift fall back should work but you would need to spend some time with a converter rep.

I think the 4.30 gear would work since the engine should make peak power right around 7000 rpm. The converter will probably slip around 10% so driveshaft speed is 6300 which works out to roughly 130 mph.

Sounds like the current combo is a good candidate to try the roller cam swap first and see how it pans out.

If you pull the heads off to swap the springs/retainers/etc, then I’d have them milled a bit to sneak it closer to 12:1.

Post a pic of a representative time slip.

Cool car

I agree with the cam swap. I would also suggest picking up an inexpensive data logger. Maybe borrow one from a buddy if you don't want to buy one. If you can data log Engine RPM and Driveshaft RPM you'll be able to help a torque converter mfg pick the correct converter for the car. You might pick up up one or two tenths with a "perfect" converter. Really good converters are expensive, but they are still cheaper than a lot of other upgrades.

This is a time slip from last weekend. I didn't mention but the car has 2' hooker super comp headers, and a hood scoop. I put a fiberglass hood on last year.

Put that thing on a diet. That's impressive for a big car.

I don't think a cam change is going to be the best for that you need a better 60. If you spend 1000+ on a roller I bet you go slower. You need more compression to go with a bigger cam. More compression is probably the best bang for the buck,even with the current one, like at least a whole more point. If you find a tenth in 60 you 'll be there no problem.

What type of converter do you have now?

At what RPM do you launch?

Have you calc'd the slippage?

Are you running bias or radial slicks?

What's your trap RPM at 125 MPH?

At what RPM do you shift?

Have you sealed the carb to the scoop?

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How do you like the UNSS series? I've been looking at getting into it if/when my old car is running again.

Are the heads out of the box? I would think milling them to get to a higher compression (I'm assuming you're running race gas anyway) combined with skilled bowl and chamber porting that enhances the mid lift flows would make more torque/hp would help the ET more than a cam swap on your stock heads. From what I've seen it's not too hard to pick up another 10-15 cfm particularly in the .350-.500 range, so IMO that would be the rough equivalent of adding cam lobe "fatness" (as far as cylinder filling) without impacting the seat to seat cam/converter relationship the car already seems to be working well. pulling up the mid-lifts would be closer to making your flat tappet feel more like a roller with no downside.

I launch the car between 2800 to 3200 depending on rt . The converter is from dynamic it's a 9inch.
Never calculated the slippage. Not sure how to do that without a data logger.
I'm running Goodyear radial slicks. BTW they don't work as well as the hoosiers I was running
My trap RPM is 6600 and I shift at 6400
The scoop is sealed to the hood I attached a picture

The UNSS series is good, I enjoy the competition. There was a large turn out last week almost 70 cars competing.