Sounds like a good plan. I'm working on a 63 1/2 Galaxie right now with a 427 side oiler that has been stroked to 482. It has dual throttle bodies on a tunnel port type intake. He wants to take all of his grand kids cruising next summer. We put cal tracs on it and four wheel disc brakes so it will be ready to handle the power. I think it will be fun watching some of these bigger cars go at it.

Aren’t the header options for C bodies pretty limited?

Are 2” with 3.5” collectors available?

TTi shows a 1 7/8 header for C body cars with a 3 inch collector. That would be a tad on the small size for a 540 inch engine. Probably cost some power on the top end.
https://www.ttiexhaust.com/TTiC6573-440178.htm

Unfortunately those are the biggest available- I have a set of the 1 7/8" x 3" headers waiting to go on the car, along with a full 3" exhaust and Hooker Aerochambers. I know they're on the small side for any stroker big block. The header adapters TTI included are also not great for airflow, they have some weird bends.

I can't fab headers myself but I am planning on cutting the collectors short before they neck down to 3", and then running 3.5" from the collectors to manual cutouts, and then 3" back from the cutouts to the rest of the exhaust. Can tell in this pic that the header adapters take 2 tight 90* bends on each side to get to the relief cutouts in the subframe.

Definitely brings up a good point that the TF270's are already on the small side and will peak at something like 5500 rpm on a 572, and then it's going to be choked a little further with 1 7/8" primaries. Think that's further indication it's best to keep it at 540-ish for displacement, that should move the powerband back up some.

Big Tony (Mixon) had custom 2 1/8 or 2 1/4" ones made for his 71 Fury by someone in Chicago for his SR headed 440 of unknown displacement....in 2001. That car was in a wreck, I wonder if those headers are still around. I'll try to ask around about them or who made them.

Thanks Jeremy, that would be a miracle if there was a set of large primary C body headers lying around in a garage someplace!

Edit: Dwayne, also found a thread where you tested 1 7/8" vs. 2" dyno headers on a 542 and the 1 7/8" were down 40 hp at 6000 rpm. That's significant and is definitely highlighting one of the compromises of using the available off the shelf TTI headers on this build.

Actually, the dyno headers are 2-2 1/8 x 4……..and the FW headers used in the car are 1-7/8 x 3.5

Peak to peak the power was:
718@6000hp Dyno
678@5900hp FW(-40)

At the top of the pull the power was:
686hp@6800 Dyno
637hp@6800 FW(-49)

The FW headers were big winners down below where the converter stalls……..up 57ft/lb @4000.
But peak TQ was slightly higher for the dyno headers.
677@4500 dyno
673@4500 FW

I’ll quantify this statement by stipulating; “on the dyno here”……..
I don’t think it’s going to be slam a dunk that you can make an “easy” 725hp………..with a TF headed 540, on pump gas, with a valvetrain/drag n drive friendly camshaft……..using 1-7/8” headers………especially if they have 3” collectors.

The motor that produced those numbers above was about 11.5cr and used prepped Indy EZ-1’s(about 340cfm), a 440-3 manifold and an 1150 Dominator carb.
Doing nothing but swapping the heads for TF270’s may or may not have gotten the power solidly over 700 while retaining the small headers.

On a car with full exhaust and mufflers the difference would probably be less. The big tube headers probably don't evacuate as well once the system has some back pressure in it.
For a big street engine it is probably best to just depend on the torque curve to move the car. Pick a cam that has good, or good enough, drivability, and the power will end up where it ends up.
We would use our 2 inch dyno headers for a build like this and I'd expect more than 700 hp unless the cam was super small. But there can be a lot of difference between a production car headers and a really good dyno header.

I agree that the proposed TF270/540 combo is an easy 700hp build………with the dyno 2 x 3.5 headers.

In my build above, I’d expect replacing the unported EZ’s with the TF270’s would add a little something to that 718hp number.

I suppose the cam timing could be played with a bit to compensate for the less than great exhaust system. I've never gone down that road very far, but I suppose someone has. The little bit I played with it seemed to be counter-intuitive. I assumed the cam would need more exhaust duration to make up for cast iron manifolds but the opposite appeared to be true. As far as I could tell, leaving the exhaust open too long just pushed more exhaust back into the cylinder. The best cam for my old manifold engine was a single pattern. The split pattern cams with more exhaust duration all had less torque. This was not a "perfect" test since I changed a lot of cam events at the same time, but it did make me think about it.

That's really helpful, thanks guys. Dwayne, after I found your post on the 542 I started to think 700 wouldn't be that trivial to make with these heads on a 540, and with the additional info on the combo you've definitely reinforced that- it's not going to perform better. My heads aren't appreciably better and the induction won't be any better either.

It should be nice, torquey, hopefully near 700 hp, and work well in a heavy car but is only going to run a little better on motor than how my car currently runs on spray, just need to prepare myself now so I'm not dissapointed in a year after spending the money and putting it in the car. Most of the benefit will be a rotating assembly and block that won't be on borrowed time if it gets a 250 shot sprayed through it all the time.

Is there any benefit to overcamming it some, and bumping the static compression up to something like 12:1, and trying to keep the dynamic CR at a value that's pump gas friendly? Or not worth the 1-2% power improvement? Imagine the tuning window gets a little smaller at that point.

That definitely seems counterintuitive, Andy. Searching Speedtalk and there are similar posts too, would've never guessed that single pattern is better. I've read that both nitrous use and restrictive exhausts favor wide LSA's but wasn't sure on patterns.

Going to order crank and rods soon, assume 6 bolt is ok, 8 bolt isn't needed at this power level.

700 hp on the dyno with dyno headers won't be a problem with that engine but I don't know how much RWHP once the engine is in the car. I don't think I'd increase the compression much over 10:1 unless you have access to av gas or are willing to buy race gas and mix fuels. The pump gas compression ratio won't get in the way of making 700 hp with those heads and 540 inches. I think it is really a camshaft decision. Where do you want the power curve to sit at, how lumpy of a cam are you willing to put up with, and how are you going to decide what the timing should be to work with your intake and exhaust systems?

Here is a short video of a customer's car. This is a 505 with pump gas compression, TF270 heads with a ported Indy intake. He is running a 4150 flange Sniper XFlow and a solid roller cam. I think he has the same 264/268 Comp roller that Dwayne designed for my 470 dyno engine. This engine made a little over 700 hp on the dyno. I think peak was 713 or something like that. It has a very lumpy idle. The idle was too radical for a four speed so he had to switch the car over to a 727. It drives pretty well with a high stall converter and it shows a lot of potential at the track. I think it weighs around 4000 lbs so your car might be a bit heavier. I think this car ran high 10's the first time at the track but I'm not sure. He hasn't taken it to the track much so it isn't sorted out yet.
https://youtu.be/fGiFuOuBnvQ

Suggestion for you. You spent all that money on a nice block, great choice. Why not make it more bulletproof with a dry sump. I know how much more it costs, that’s what I did. It’s not a whole lot more than a good wet sump setup. 2cents.

Thanks, I'm totally, completely ok with that level of idle chop- my car is almost as bad right now with the 0.590 solid in it.

https://youtube.com/shorts/0JXBtCaDklA?si=IWh1aJWk2TNNq-HB

we have pump 93 here and any time it gets sprayed I do mix race gas in it for safety, but on motor would like to keep it pump gas friendly. Sounds like bumping the compression up to the ragged edge is not worth the hassle.

Thelma- I am struggling a bit with that decision. If it was in something other than a C body a dry sump makes sense but it would require an oddly shaped custom oil pan to start with and I don't know how much of the subframe can be cut away to put a better shaped oil pan on it. $15k seems to get me a solid 700-ish hp pump gas street motor, that meets my performance goal on spray. I could spend $30k and move to something like the BES B1 heads with custom 2 1/4" headers and make 850+ NA, but I think that is more radical than what I want this car to be on the street, and definitely more than I want or have to spend. It does seem to be a bit of a waste to buy a good block and build such a low output motor but the goal is durability, and if it never spins past 7k I don't think a dry sump really buys me that much.

Maybe someone with one of the better engine sims can model your combo, with the small headers…….. and play with the cam timing a bit and see what the trends look like.

the 1/2" diameter loss of the 3" collector will limit you far more than the 1/8th inch of primary size, the collector will be like a Peak Torque RPM cork and limityour torque peak to a lower RPM, whereas the primary will slowly pull down the power (relative to the larger pipe) at whatever that RPM peak is achieved.

I whacked the 3" collector of a set of Hooker 1 7/8" at the back of the primary tubes (shortening them a bit too) and slid on and welded a 3 1/2", And when I went from a RB standard port to a Stage 6 headed low deck with the raised ports I never even had to take the collector flanges off the X pipe! fit perfectly.

For what it’s worth, Aviad is advertising the entire setup on their website for 3700.00. You will probably want a bigger tank than what they offer, they can be had from Stefs or Petersen. I’m not sure if their prices are up to date, but their pan depth would probably fit above your K member with no trouble. Take a look at Aviads website, you may find it interesting. Dry sump was worth it for me, about 25 additional horsepower on the dyno. Bes ported my 440-1 and manifold, I do have aluminum rods and higher compression than you may want, but I made 850hp easily with my bill miller aluminum block. Mine is 572 also. I understand the radical part, my car is strip only.

IF you are considering buying heads from BES, just call there and ask them, what to do, get the heads, cam, intake all from them???

Block showed up today! FedEx even wheeled it into the garage for me. SN 1082, I understand why they can take so much power now, the difference in the mains is impressive. It came with all the hardware needed and cam bearings as well which was a nice touch. Need to figure out what rear main seal to use. The included pickup adapter is 1/2" NPT. I still need to flip it over to make sure all of the head bolt holes were drilled!

Wize, I definitely think I can cut the collectors off these and change them to 3.5". Making headers isn't in my skillset but I do have friends that would help me redo the collectors. I want to do 3.5" to cutouts, then 3" to the rest of the exhaust.

Having to temper back the scope creep. A dry sump and the full BES top end with their B1's looks killer, but that's gonna be another $15k to spend, including getting custom headers made. That's a decent value to add another 300 hp. A relatively mild 540 with my plate kit is going to get me to where I want the car to be though, and worst case am thinking I could redo the top end later if low 10's isn't quick enough.

Thinking I only need a 6 bolt crank, going to order them and the rods after Christmas, along with a bunch of stuff from Summit. Also thinking head studs over head bolts. Will measure tomorrow to see if I can fit the 440-2 Indy intake underhood or if I need to stick with the TF 4150 intake and then port match it myself.

6 bolt crank is all you need but before you decide double check availability on flex plates. You'll want a high quality flex plate for that engine and sometimes 8 bolt ones are easier to find in the SFI grade. Head studs can be a nice upgrade but sometimes they'll interfere with the header flange. With the power you'll be making you need to upgrade a lot of the little parts. You'll need Cometic head gaskets for example, and the best bearings. The one piece rear main from Fast Fish is usually a good investment but you might want to talk to the engine builder before you buy too many parts. Some engine guys only want to use certain parts.