To port or not to port?

I've been playing with the 543 build on my computer while I wait for the block to return form the machine shop. Computer dyno software has it's limitations but it should be good for an A to B comparison for properly calculated changes. Knowing this, I modeled my 543 build in Dyno Sim 6 as well as possible. The head flow data came from Hughes website so it may be a little biased. Still, those are the numbers I had so that's what I used. I selected the Hughes SEH3236BL-10 cam for the calculations. It was understood from the start that my old Eddy heads were going to be the choke point on this build.


Knowing the 543 is going to be dragging around 5300 lbs of Imperial wherever I care to go means it's got to be a mild build that still makes plenty of vacuum for power brakes and remain a low maintenance reliable engine.

Check out the projections below. Consider the shift points with a 727 and where the power begins to roll off. Would you pay the $1600 they (or other porting services) want to do a full CNC port job on these heads? The results are on par with their porting results on other common heads.
I don't see massive flow differences between other aftermarket heads below the .550" lift that I'll be playing in.

Thoughts?

Obviously, stock heads are on the left and full CNC ported heads are on the right.

I wouldn't pay Hughes a dime, but I would talk to Dwayne Porter.

I spoke to him about the cam choice and porting.

The biggest reason I went to Hughes for the info is that they've flowed a bunch of different heads and have the numbers on their site. I like that better than looking at heads that were tested on a hundred different machines all over the world. I'm a data guy and a single source makes for a better A/B comparison in this situation.


As for the fondness (or lack thereof) for the company, that's one of the biggest things that drove me away from racing. There's a non-stop hate fest going on. Racers piss on one guy and put another on a pedestal while the next racer does just the opposite. It's as hypocritical as the 350 lb driver spending thousands to build a light weight race car while refusing to go on a diet himself.

At the very least get a good valve job, Back cut on the intake valve, bowl blend & you will be good to go.

I am betting bowl work, biggest valves, what ever gives you excellent flow numbers up to your max lift will be your best choice. A wide 110 lsa on a motor like yours sounds all wrong to me. Small heads, HUGE motor! Likes overlap. The question is how much overlap can be used and not screw up the manners down real low? Vizzards book on power has a chart that says a 540 with those heads could do best with a 100 degree LSA! But obviously it might have a pretty ratty idle. Some Harley cams have a similar situation, and aftermarket grinds can be had with 98 LSAs! Something to think about. Time to consider a REAL custom cam!

Small heads, HUGE motor! Likes overlap

This^^^

No hate here, I've ran two of his cams, both made good power but neither held up well. As far as their flow numbers go, I'll let that dog lie.

Porting should be a good investment on an engine that big, even if you don't turn it much more than 4500 or 5000 rpm. I've used Hughes before for port work and they do a good job. I ran a set of their CNC ported Edelbrock heads on a 427 inch SB and it made excellent power. I wouldn't have any problem sending the heads to them. You should have them port match the intake manifold at the same time.

While I agree porting the heads would def be worth power on that combo........Spending $1600 to port some RPM heads wouldn’t be a viable option for me.

If you already own the heads, you could sell them for as little as $600, add that to the $1600 the porting would cost...... and buy TF240’s...... and be money ahead.

The numbers they have on the site are “ optimistic” at best
Would wager 95% of people on here would agree.
I would get your Eddies CNC’ed at Modern and be done with it. I doubt they anywhere close to 1600

This is a street only, DD build right? I would just use them as is. I'm running OOTB Eddies on my 512 and it still spins the tires on a 40 roll with a 3.54 gear and 285 Nittos. It's going to be like driving around on ball bearings as it is. Save the money.

Yes, the 1.46 valve spring TF240 heads are only $962 each from Summit (free shipping) so that is around $1900 for new heads. Not sure if the $1600 includes shipping back and forth to Hughes. If it doesn't then you'll need to add another $200 to the bill since 50 lbs heads are going to be expensive to ship. The existing Edelbrock heads should be fairly easy to sell locally for a few hundred each.

I would have to agree, trying to feed a 540 with the Eddy heads even with some porting is not going to be money well spent. My best guess, that on the drag strip, porting those heads on a 540 maybe a tenth in ET. Spend the money for a CNC job on a better set of heads.

No one has mentioned that 3,300 is the dividing point. The porting offers no help below that point, either in torque or horsepower but does pick up a good amount above that. Where do you plan to spend the most time? Above or below 3,300? And how important is that extra power above 3,300 to your planned usage since there is no gain (actually a little loss) below that. That much low end grunt trying to push that heavy boat will be a major tire-fryer anyway, so would more of the same even be usable?

Why not just try the heads you have as they are to see how you like it? Would it be that big a deal for you to throw the extra coin at them later if you just had to have more? Also, if you wait and still wanted more, you would have a better feel whether you would want to just port the Eddies or move on to bigger, better heads.

You have a point if the OP is wanting a lot of power above about 5,000. But up to that point a small port head on a 540 will be superior in torque output where this deal will want it- 2800 to 4000 maybe? Having run a 535 with ported 906 heads, i can vouch for the torque!

Has anyone ever seen a street type stroker with a reasonable cam not have tons of torque? I've built two small block street/strip strokers, one with a 4" crank, a 408 and my current one with a 4.125" crank, 434". The 408 had Curtis Boggs ported Edelbrocks with a 260/264° @ .050, .628/.633" flat solid. The 434 has ported Indy 360-1's with a Comp 263/271° @ .050, .711/.719" solid roller. Neither of these engines have been soft on the bottom end, anywhere on the bottom. I understand I'm running a lighter car with more gear, but I find it hard to believe that unless something is way out of kilter in the combo that you're going to make a street type big block stroker soft on the bottom. I guess if you put a set of old pro stock wedge heads on a very low compression build with a huge roller and a 2.76 gear in a dump truck you could muck it up. There is always that guy, but I don't see feets as being him.

Modern Cylinder Head ported my Stealths ~4 years ago for $750.

I should havé mentioned this before--- how much flow can be gained with some basic mods? Like bowl porting, backcut valves, whatever will improve flow down low on the cheap? Much less costly and might meet your needs real well. That certainly would raise the torque up above 3200, probably give you 75 percent of the power gains a full port job would?

I sent an email to MCH to get their opinion on porting vs replacing.

Every BB I've worked on made more power by helping the motor get more and fuel
That include bigger cams, bigger carb, more carbs, better exhaust, bigger heads and better heads and so on

Personally, I think you are overthinking this.

If you really feel like you want more power, sell the Edelbrocks and buy some Trickflow heads, as Dwayne suggested.

If it was me, I'd just run what you've got.

I don’t know how big the $1643 job from Hughes is, but the MCH cnc job actually makes the heads bigger than the TF heads.
240cc vs 252cc.
At 540+ cubes, the volume could pay off.

If the price was right....... I’d say it’s a good option.

Do yourself a huge favor. Call Dwayne.

Based on the dyno testing I've done I'd say that TF240 heads work better than MCH ported Edelbrock heads. I've dyno tested them both and the TF heads work better. Not a ton better, but they do work better. If it was my engine I'd buy new TF240 heads and sell the Edelbrock heads as is. I think that will be the least money for the best result.

It would make for a good back to back comparo test.
Throw some of the biggest Hughes cnc version into the mix as well(as long as we’re doing some imaginary testing).

Mill the Ede’s down to the same chamber volume as the TF heads to eliminate that variable.

If you’re starting from scratch....... the decision is a lot easier.

I'll do a back to back test early next year when I change my 512 low over to TF240 heads. Right now it has MCH ported Edelbrock heads on it. I'm sure the TF heads will pick up power based on the testing I did with my Coronet engine. I ran both heads on the Coronet engine and the TF heads worked a little better. A little more torque and a little more power. Nothing huge, but roughly 10 to 15 better at the peaks with everything else very close to the same.