So….more header talk….this had me scratching my head

So….. sitting in the staging lanes Saturday( had a good bit of a wait before before we got pulled, talking to Vance, guy who drives the Rod Shop Dodge Dart( races it in stock).
Up walks a guy I have met several times at a get together a good friend of mine has once a year.
His name is Chris Hardy. He owns RET, racing engine technology. Tons of guys nationally run his heads in stock and super stock.
Him and his dad were hitters in 6 banger Buicks in stock forever.
Anyhow he asks how my car was running, I said OK, but better when I get around to getting bigger headers for it. He ask me a few questions. I had told him of the recent “ bigger heads and bigger intake” swap. He asked how the car 60 footed now compared to before. I told him I have enough hits now to say that it’s about 3 slower. Typical 1.47 before, now 1.50 almost every lap thus far. 10 or 12 hits thus far.
Told him I was looking at putting a 1 7/8 tube on this 418. He told me no way, he would even consider anything bigger than a 1 3/4 tube with what I have, heavy car, Yada, Yada.
He says… “ you have obviously been listening to dyno guys too much. You need to think about torque, more torque, faster down the track. You have a bigger runner head now, you have lost torque, thus the 3 loss in the 60 foot.
He said a lot of the stuff he is doing, he is telling his head customers to put 1.5 inch tubes on, not even 1 5/8. I was like..are you friggin kidding me..lol
Said he just finished a set of heads on a shoebox Nova that qualified 10th with a 327/ 275 horse motor that they installed couple days before Sonoma last weekend, and in spite of having wheelstand issues car went like 9.99..13 quicker than they had ever been…and still sorting it out.
Guy is without a doubt smart, just goes against everything I have ever though I knew about headers.
Anyhow..
Signed,
Confused in Kalamazoo

I do not find that surprising at all, not one bit. As talk goes here, HP, HP, HP, HP!!!! The bigger header is the way to go. However……. At the track …….
This may not be so. A well thought out exhaust will show a bit ether way on the dyno but the track is where it counts. If you can get some cheap headers……

B3422w5 said:

So….. sitting in the staging lanes Saturday( had a good bit of a wait before before we got pulled, talking to Vance, guy who drives the Rod Shop Dodge Dart( races it in stock).
Up walks a guy I have met several times at a get together a good friend of mine has once a year.
His name is Chris Hardy. He owns RET, racing engine technology. Tons of guys nationally run his heads in stock and super stock.
Him and his dad were hitters in 6 banger Buicks in stock forever.
Anyhow he asks how my car was running, I said OK, but better when I get around to getting bigger headers for it. He ask me a few questions. I had told him of the recent “ bigger heads and bigger intake” swap. He asked how the car 60 footed now compared to before. I told him I have enough hits now to say that it’s about 3 slower. Typical 1.47 before, now 1.50 almost every lap thus far. 10 or 12 hits thus far.
Told him I was looking at putting a 1 7/8 tube on this 418. He told me no way, he would even consider anything bigger than a 1 3/4 tube with what I have, heavy car, Yada, Yada.
He says… “ you have obviously been listening to dyno guys too much. You need to think about torque, more torque, faster down the track. You have a bigger runner head now, you have lost torque, thus the 3 loss in the 60 foot.
He said a lot of the stuff he is doing, he is telling his head customers to put 1.5 inch tubes on, not even 1 5/8. I was like..are you friggin kidding me..lol
Said he just finished a set of heads on a shoebox Nova that qualified 10th with a 327/ 275 horse motor that they installed couple days before Sonoma last weekend, and in spite of having wheelstand issues car went like 9.99..13 quicker than they had ever been…and still sorting it out.
Guy is without a doubt smart, just goes against everything I have ever though I knew about headers.
Anyhow..
Signed,
Confused in Kalamazoo

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I forget, what is your shift RPM and the RPM through the traps?

Bobzilla said:

I forget, what is your shift RPM and the RPM through the traps?

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Light set at 6300, so I shift at probably 64/65, stripes about 65-66 in the 1/4.
Less obviously in the 1/8

I just stepped up to a 1-7/8 TTi header because that's all they had in stock. I know what my motored dyno'ed at with 1-3/4. It'll be interesting to see what it'll do on the chassis dyno.

Granted, I will be spraying the piss out of it

Sounds about right.
Go over to speedtalk forum and search for everything posted by Calvin Elston. IIRC screen name "exhausted"
And/Or do a search here for that name as I've posted some links in the past.

Another name to look for is Larry Meaux. He's the creator "Pipemax" software, and has a shop in Louisiana.
But I think Calvin's explanations are useful.

Mattax said:

Sounds about right.
Go over to speedtalk forum and search for everything posted by Calvin Elston. IIRC screen name "exhausted"
And/Or do a search here for that name as I've posted some links in the past.

Another name to look for is Larry Meaux. He's the creator "Pipemax" software, and has a shop in Louisiana.
But I think Calvin's explanations are useful.

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Larry Meaux( also an elite head porter) was sent these new gen Bloomer heads to evaluate. He liked them…a bunch.

We race a number of Small block Mopars.
Even our Superstock 340 Duster was definitely quicker
with 1 3/4 Hooker Headers than any 1 7/8
Header we tried and we tried a lot (The TTI Step 1 5/8 to 1 3/4
is faster yet in our applications particularly with correct stepped collector)
It was one of the First A body Superstock cars in the 9's (Especially
in SSKA @ 3400 lbs).
Of course for the last 30 years we have gone to Proprietary Multiple
Steps headers which a quite a bit faster than any single tube size pipe
header. We guard the specs on these and collectors pretty closely.
If you get to a Division or National Race try to get a peek at the headers
on any cars with similar engine family to yours (If you can without getting attacked).

I will tell you that IF you want to do a header like Calvin Elston builds, then you really need to start over with your entire program. That is because (this is as close as I can get to how he explains it but you can certainly go to speed talk and yellow bullet and search his stuff and read it so here goes…) almost all exhaust ports and exhaust valves are too big. I agree with that. So, if you can shrink the exhaust valve and port and then make the intake valve and port bigger, you can use a header like he builds (a tri-y design with…now I can’t think of it…a merge collector) and if you change you cam timing to match I believe there are some huge power gains to be made.

The problem is how many of us are going to do that? If I was younger and I was up for 40 plus hours of welding and all the R&D I’d do it. But I’m not young and I’m just not into it.

I will say this though. Cam timing, compression ratio and header cross section are very much intimately related. Trying to change one and not the others will not produce decent results.

I cant tell you how many times I’ve tested what is considered bigger diameter tube headers and not one single time have I lost power. Not once. BUT…I also picked the cam timing or the engine they were going on already had favorable cam timing. So what is “favorable” cam timing?? We have to talk about the heads.

All in-line wedge heads are deficient in overlap flow. And you NEED overlap flow. Without overlap flow, the engine will be what I call numb to almost any changes one might make. I know we’ve all seen engines like that. You can port the heads and the results suck. Change the intake manifold and nothing. Bigger headers and again nothing. BTDT. We also see it on dyno tests all the time. They also don’t respond to normal tuning changes. The engine is just numb.

When you see something like that, bet everything you have that the cam timing is wrong. It is the brain of the engine. And a numb brain means a numb engine.

Contrary to popular belief, lower compression engines usually need a bigger primary tube than the same engine with a larger primary tube. It’s all related.

So now we have a relatively high compression ratio and no overlap flow and you bolt on bigger headers and…nothing. And I’d bet when the big headers went on, you had to add jet. That’s your clue the header isn’t working. Big jets are SLOW.

Look at a Hemi. It has incredible overlap flow. So much so that you need to do things to reduce it or you throw power right out the pipes. The in-line wedge is the other end of the spectrum.

Speaking specifically about carb applications, you need to pull on the booster as hard as you can. Anything you can do to pull the booster harder will make the engine make more power.

The number one killer of overlap flow is wide LSA’s. It just kills overlap flow and makes the engine numb. The closer to correct you are on overlap, the more power you will make because you are using that overlap to pull on the booster. The same goes for head porting. If you port the heads and flow more, but it requires bigger jetting, you can almost bet it will lose power. You lost the pull on the booster. It seems counter intuitive but that’s how it works.

The current trend has been for years now to reduce seat to seat timing (not bad if you do it correctly) and then open the LSA up to extend the RPM range where they need it. Invariably that engine will be numb to tuning, header sizing and intake manifolding.

So the header gets blamed when the cam is the issue.

We just went from 1.625 to 1.875 headers on @lead69’s Dart. The engine was pretty close on tune before the headers. Just bolting on the bigger headers made the engine pig rich. And most would jump to the conclusion that the big header was killing it. In fact, the opposite was true.

The big header actually was pulling harder on the boosters and even on the idle circuit (which is exactly what you want the header to do) and made it pig rich.

I had to go up .008 on the idle air bleeds, but I really need to go in and reduce the idle feed restricters some and go back down in idle air bleed for drivability.

I went 7 sizes SMALLER on the primary jets and 8 sizes smaller on the secondary jets. It’s pretty close at a cruise but it’s still a bit rich at WOT.

And all that is because the compression, cam timing and header size are working at overlap to pull on the booster.

If you bolt on better header or a better intake and it does nothing or goes slower, look at your cam and what you have at overlap.

Well said.

I went from a 1 7/8 Hedman Hussler race header to the TTI 1 5/8 to 1 3/4 step header on my stroker small block and have had better performance. I'm not hip to all of the science that Rat Bastid mentioned above (that stuff is just voodoo magic to me) all I know is I didn't lose any performance. Now, I will say I had to play with carb jetting to find the happy spot, which could point to some of what he was speaking about.

So is there a "formula" for figuring out what primary tube diameter is best for a specific cam LSA ? I'm sure it's different for max effort race set up and street car. When I had the headers made for my 528 Max Wedge headed solid roller 308R the guy asked me why I wanted 2 1/8 pipes. I couldn't answer and he asked what dyno headers were used. 2 inch. He said then that's what we will make.
Race car only 66 Valiant so no aftermarket headers were available.

Not really. Too many other factors. In addition to cam specs, RPM range(s) of most interest, displacement, VE are three of the big ones. Pipemax will show the effects of changing the variables. At least for me it was well worth the price of admission. YMMV

Mattax said:

Not really. Too many other factors. In addition to cam specs, RPM range(s) of most interest, displacement, VE are three of the big ones. Pipemax will show the effects of changing the variables. At least for me it was well worth the price of admission. YMMV

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Thanks anyways. I should have put more research into it before I committed. On the other hand there aren't a lot of people that do custom headers near me. Obviously I had to bring them the car. I believe the dyno place used the 2 inch cause that was what they had for a BB Mopar. 707 hp with MW Stage 6 heads that only flowed about 325 at 650 after Dwayne Porter worked them.Not complaining, just wondering if I should have done something else.

Les Gibson said:

I went from a 1 7/8 Hedman Hussler race header to the TTI 1 5/8 to 1 3/4 step header on my stroker small block and have had better performance. I'm not hip to all of the science that Rat Bastid mentioned above (that stuff is just voodoo magic to me) all I know is I didn't lose any performance. Now, I will say I had to play with carb jetting to find the happy spot, which could point to some of what he was speaking about.

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If you don’t mind, can you post your cam numbers, compression ratio, gearing, converter stall speed, intake manifold…that should help see what’s happening.

Edit: tire diameter, shift RPM and trap RPM too if you don’t mind.

A lot of old school advice is going out the window as computers are unboxing some of the magic.

It makes sense to me based on what little I know about it.

Interesting stuff.

Actually Calvin built his headers for the engines he was given.* In fact he often mentioned that he rarely got any opportunity for input on the engine. One of his main working points was that "blowdown length" is "king"
While one doesn't want to restrict at maximum output, it is just or more important to keep velocity of the mass flow moving away from the port through the entire rpm range of interest. This is what Mr Hardy is driving at when he's talking torque.
See Novice exhaust question: What is "blowdown length"? - Page 2 - Don Terrill’s Speed-Talk

With a 4 into 1 design, pipemax will show pretty much the same. We just dont get the explanation from Larry to the extent we did from Calvin. In general their findings agree, even though Calvin did not do engine work and did much more roundy round. Larry also has a small forum for pipemax users. I havent been on for years but good stuff there.

But the simple answer is plug the numbers into pipemax and you'll see what sizes pipes are recommended for what you are doing with that engine. Then you can see if the headers you're looking at will move you in the direction you want.
___________________________________________________________
*eg 1 5/8” headers and 500hp? - Page 7 - Don Terrill’s Speed-Talk

**Larry Meaux regarding some sizing relationships Bill Jenkins , Larry Meaux and header wisdom. - Page 3 - Don Terrill’s Speed-Talk

66Valiant528 said:

707 hp with MW Stage 6 heads that only flowed about 325 at 650 after Dwayne Porter worked them.Not complaining, just wondering if I should have done something else.

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You mean on the cylinder head choice?
How many cubic inches is the engine?

Now, from what I was told & heard, there were multiple Stage VI castings. One version that was, “More Portable” than the base VI casting. IDK if that’s true or not.

What I do know is that MoPar was still using the stock architecture in trying to develop the head and hitting a wall in performance. The slight adjustment made in moving the rocker pushrod area over offered more of a ceiling. But it was still something of a stock replacement head in aluminum.

Chapman had the beauty of being able to have MoPar approach them for help. I’m sure they had more than just a couple of sets to cut up to learn just what can and can’t be done on porting.

Dwayne found 325 cfm? I’d call that smoking good.
The head is limited and his results are really good for sure. 707 hp? Yea buddy!

Here’s the flip. What else was available at the time at what cost?

Dwayne didn't like the heads. No raised roof and stock length fat valves. I worked at the dealership and got a great deal. And frankly at the time like 12 to 21 ? years ago there wasn't a lot available. The Chapman's were but out of my price range at the time. 528 cubes matching MW port single plain M1. I picked the cam that fit Dwaynes recommendations. Less that 670 lift and as much duration as I could get away with. Mopar P5155616 657/659 308/315 275/282@50 Apparently it works. Even the dyno operator (a known Chevy guy) seemed surprised.

Told him I was looking at putting a 1 7/8 tube on this 418. He told me no way, he would even consider anything bigger than a 1 3/4 tube with what I have, heavy car, Yada, Yada.

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What was the predicted performance gain with the 1-3/4 over the 1-5/8 on your combo?

PRH said:

What was the predicted performance gain with the 1-3/4 over the 1-5/8 on your combo?

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I never asked him. His big point was do whatever you can to build torque, he seemed to think going any bigger at all would be a mistake. Threw me for a loop??

B3422w5 said:

I never asked him. His big point was do whatever you can to build torque, he seemed to think going any bigger at all would be a mistake. Threw me for a loop??

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Now for the 700.00 question. Should I trust him. Lol.

Rat Bastid said:

If you don’t mind, can you post your cam numbers, compression ratio, gearing, converter stall speed, intake manifold…that should help see what’s happening.

Edit: tire diameter, shift RPM and trap RPM too if you don’t mind.

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Comp Cams roller, gross lift .654 intake, .655 exhaust, duration @ .050 269 intake, 276 exhaust installed at 106.0 center line.
13.9:1 compression, 5.13 gear, approx 5000 stall with 9 inch converter, edelbrock victor W2 intake with either a first generation 1050 dominator or a Quick Fuel 1050 dominator style carb, I run both. Tire diameter is 31.5, shifting at 6500, trap rpm in the 1/8 is about 6700, 1/4 around 7000. These trap RPMs are a best guess as I can't recall the exact numbers.

pittsburghracer said:

Now for the 700.00 question. Should I trust him. Lol.

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he is a little hard to talk to. Very, very opinionated.
I looked up what he said about the heads he just did and we’re put on before Sonoma in that Chevy 2.
Sure enough, qualified 10th. Chris said they were unloading the tires at the hit with big wheel stands and the car was still 13 faster than it had every been before.
I don’t doubt his results, he has been involved as both a racer and head guy/ engine builder for a long time.
Met him two years ago at a friends house at an annual party they have. My buddy, the host, has had him do work on several of the street Vettes he owns, which is how they met.
I had never heard of him or his business at that time.
Vance Cummins has his heads on his Stocker Dart that runs well into the 10’s, and had his heads on the car when it ran in the old IHRA Top Stock class( very fun to watch) mid 9 sec motor back then.
I didn’t even know Vance used him till last weekend at the NMCA deal