some flow numbers off of the new head

Hamilton Cams said:
I'm cutting one tomorrow! We are going to just add a plate after cylinder 4 that has an o-ring. It only has to hold 15-17psi coolant ;)
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care to send it to me when your done?? lol!!! No, if you think you may do a small run of 4B heads, let me know. I want one.
 
Sorry, that would be a completely different tooling bill which means it will be much cheaper to chop off two cylinders. An oringed plate on the back will fix her up. I post pictures when we are done.

Zach
 
I can take that 2cyl drop off yer hands for ya.:D

I'd like to experiment before I start making chips in a good head.
 
chop the back two off one, front two off another... repeat process w blocks....... build a bad ass straight 8 !
 
Hamilton Cams said:
Sorry, that would be a completely different tooling bill which means it will be much cheaper to chop off two cylinders. An oringed plate on the back will fix her up. I post pictures when we are done.

Zach
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have you got a picture of the head cut up for the 4 bt
 
We are on the fence with the 24v. If we nix the tubes and go for a CR feed through the valve cover then we would have to as well for the 24v. Going through the traditional connector tube will really limit how it will flow.

I'm in overload mode right now with the 12v head development, 8.3l economy cams , ISX economy cams, 6bt economy cams and high compression pistons for the 6bt 12v and 24v and fast rate p-pump cams. I'll post updates on the 24v head after I meet with some injector gurus and the 6bt head that is chopped to 4bt when we have time.

On a side note if you know of any 8.3l(6ct or ISC) guys that are willing to test an economy cam, tell them to email or call me at the shop
 
Zach.
It seems like flow from a cylinder head could be represented by a graph of a single valve event multiplied by rpm. Flow starts as soon as the valve begins to open and stops when the valve finally closes. If pressure inside the cylinder is held constant(don't know) the ramp up and ramp down seems like they would be mirror images of each other(if the graph shows lift on the horizontal axis and flow on the vertical axis). The total amount of flow would be the entire area under the curve. My question is in regard to low lift numbers. My head flows :
INT:
(lift)
.200 192
.300 256
.400 260
.500 266

EXH:
(lift)
.200 205
.300 255
.400 280
.500 284

Is there a way to compare total flow from a head that has more flow at low lift, but less at high lift? Low lift occurs on each side of the graph, in effect increasing the base area while high lift flow would seem to affect a narrower area at the peak of the flow curve.
I know nothing about these things and am just trying to understand some of math behind all the hard work you have been putting into this project.
Thank you.
Ron Allen
 
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I have this conversation with people all of the time.

This head is adding to the debate, but I'm glad you asked the question. We do not have a visual interpretation of the flow numbers at this point like a dyno graph, but that is a great idea. A lot of people are more visual as opposed to crunching data and interpreting how the data will affect their trucks. I will say that on street trucks, .100", .200" and .300" data is much more important that higher lift numbers. I will see if I can find a way to quantify airflow at a given lift for a given duration.



Here is what I tell my customers: Before flow numbers can be considered, you need to know what the RPM range of the engine is. I was setting up an engine for a gentleman and I asked him what rpm range he was going to run. Well I drag race so just off Idle to when I shift at 4000RPM.

Alright, you need the 188-220 cam, I tell him. It works better than any cam we have done to date from just off idle to over 4300 RPM. Well that is good he says, but lift is only going to be .533" at the valve and this head does not peak until .675". I need more lift he tells me. To get you to the .675" you want, I will have to put a big duration sled pulling camshaft in your truck that does not come on until 4000rpm, you will need a big stall convertor, and a very large pump that flows well as high as possible. Well how am I going to get the Flow I need with such a small cam? he says. This is a guy coming from a stock head, stock cam to this new setup.

This is where a customer needs to be realistic with what they need. RPM range dictates duration. Duration(since I push the designer to the limits of lift vs. duration)dictates how much lift you can have.

If the rpm range dictates what duration cam you run and the duration camshaft dictates the lift potential, then in a round about way the rpm range dictates where you want the head to flow.

It is pissing in the wind to get the head to flow well at .800" when you are lifting the valve .500"! I am constantly told (in the nicest way possible) that I am an idiot because I tell customers that they do not have to cut the pistons on their 4500rpm drag truck to get the best cam for them. One of the biggest mistakes people make with their builds is over porting the head and over-caming the engine. This is true in Gas engines and as more and more hard parts become available to the diesel world, it is true for us as well.
Matched parts will always kill a mismatched "superior" combination.


I put as much lift as I can into all of our designs. This lets the valve open as fast as possible to get to the higher flow numbers as fast as possible. Due to our higher lift designs, we keep the valve at the higher flow numbers as long as possible in a given duration. That being said, lower lift numbers for 90% of all customers are the numbers that need to be looked at because their rpm range dictates it. Street trucks spend most of their time from 1800rpm to 2800 rpm. At 1800 rpm, velocity of the port is VERY important. This means that a conservative port job with a nice valve job is the best for the application. Another way we are seeing to increase low lift numbers considerably as well as increase swirl is pocketing the head around the valve. This greatly increases the ability of the air to enter or exit the cylinder at very low lifts and is very important in power production at lower rpm ranges.

The downside? Lower compression which hurts lower rpm performance. This is why we are working on higher compression pistons for the 12v!
 
Well after a bit of time playing with different valve jobs, it looks like the best bet for street trucks running cams under .320" lobe lift need to run a 30 degree intake valve angle. Combine that with .050" taken off of the head and you will see a big increase in low lift flow. Al lot of people put a lot of attention on higher lift numbers at .600" and over, but that is not necessary on a street truck with .500" lift at the valve.

Zach
 
Hamilton Cams said:
We are on the fence with the 24v. If we nix the tubes and go for a CR feed through the valve cover then we would have to as well for the 24v. Going through the traditional connector tube will really limit how it will flow.

I'm in overload mode right now with the 12v head development, 8.3l economy cams , ISX economy cams, 6bt economy cams and high compression pistons for the 6bt 12v and 24v and fast rate p-pump cams. I'll post updates on the 24v head after I meet with some injector gurus and the 6bt head that is chopped to 4bt when we have time.

On a side note if you know of any 8.3l(6ct or ISC) guys that are willing to test an economy cam, tell them to email or call me at the shop
Click to expand...

Our main tillage tractor is begging for one of these, not sure about doing testing, fieldwork is pretty much done, and I'd have to buy mom and dad a weekend at a nice bed and breakfast so I could get it put in without him noticing. LOL
 
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