HEAD vs HEAD 2.2 turbo = stock vs Ed Peters

[5DIGITS]

I'm of the opinion that chamber and piston design is totally dependent on intended application.
If we are talking about a moderately boosted street engine, on pump gas, then squish becomes a desirable design
consideration.
On the other hand, an all out turbo race engine, on good race gasoline or Meth, squish and quench can be unnecessary or even counter productive, especially with a small bore engine like our 2.2L. The pressure differential between the intake port, and chamber is so high at the moment of valve opening, that mixture motion and charge homogenization are pretty much guaranteed.
I have essentially no squish in my race engine and it has a wide and forgiving tuning window. I don't know, maybe I got it all wrong, but it works for me.

I agree to a point...
Where race applications benefit from whatever octane level is needed to support the task, it's supplementing and somewhat band-aiding the short comings of improper combustion chamber design and much needed squish with the use of fuel that would otherwise not be required to keep the components in one piece. When one can make equivalent power at a much lower boost level - case in point, our last dyno day that came with 300+HP @ 17psi versus the closest performer at 275HP @ 25PSI. It's the difference between making all the parts work together, as you mentioned, versus simply blowing hard on poorly matched hardware to accomplish sub-standard numbers.
It's not that anyone always gets it right, it's that someone occasionally does.

[glhs875]

I agree to a point...
Where race applications benefit from whatever octane level is needed to support the task, it's supplementing and somewhat band-aiding the short comings of improper combustion chamber design and much needed squish with the use of fuel that would otherwise not be required to keep the components in one piece. When one can make equivalent power at a much lower boost level - case in point, our last dyno day that came with 300+HP @ 17psi versus the closest performer at 275HP @ 25PSI. It's the difference between making all the parts work together, as you mentioned, versus simply blowing hard on poorly matched hardware to accomplish sub-standard numbers.
It's not that anyone always gets it right, it's that someone occasionally does.

Not trying to start an argument and that your post won't hold true, but you have left alot of things in question about the combos from the two different HP levels made. Like intake/exhaust flow of the heads, intercooler differences, any camshaft differences, size (HP rating) of the turbos used between the two, exhaust pipe diameter,etc.

[83scamp]

Not trying to start an argument and that your post won't hold true, but you have left alot of things in question about the combos from the two different HP levels made. Like intake/exhaust flow of the heads, intercooler differences, any camshaft differences, size (HP rating) of the turbos used between the two, exhaust pipe diameter,etc.

I think you guys are saying about the same thing. 5Digits references the hardware working together. It's the total combination, not just the chamber design, it's not just the porting, it's how the entire system works together to make power. It's why a guy can make 300+ hp on 17 psi, and the next guy can't do it on 25 psi... Just pushing harder on the turbo doesn't get you more power. Everything has to work together for it to work efficiently.

Like 5Digits said, it may not be that one guy gets it right all the time. Sometimes you just luck into a combo that works efficiently. There isn't one formula that works to make big power. Obviously there are some basics to making power, and those are pretty well documented. But once in a while somebody hits a combo that works that nobody really thought of...

[glhs875]

I think you guys are saying about the same thing. 5Digits references the hardware working together. It's the total combination, not just the chamber design, it's not just the porting, it's how the entire system works together to make power. It's why a guy can make 300+ hp on 17 psi, and the next guy can't do it on 25 psi... Just pushing harder on the turbo doesn't get you more power. Everything has to work together for it to work efficiently.

Like 5Digits said, it may not be that one guy gets it right all the time. Sometimes you just luck into a combo that works efficiently. There isn't one formula that works to make big power. Obviously there are some basics to making power, and those are pretty well documented. But once in a while somebody hits a combo that works that nobody really thought of...

I guess we are basically saying the same thing. I feel it would be educational for everyone to know what the differences are between the two combos mentioned. That is the main reason behind my comment to 5Digits post.

[83scamp]

I guess we are basically saying the same thing. I feel it would be educational for everyone to know what the differences are between the two combos mentioned. That is the main reason behind my comment to 5Digits post.

Yes, it would be an interesting comparison. If all the details are known.

[Shadow]

On the other hand, an all out turbo race engine, on good race gasoline or Meth, squish and quench can be unnecessary or even counter productive, especially with a small bore engine like our 2.2L. The pressure differential between the intake port, and chamber is so high at the moment of valve opening, that mixture motion and charge homogenization are pretty much guaranteed.
I have essentially no squish in my race engine and it has a wide and forgiving tuning window. I don't know, maybe I got it all wrong, but it works for me.

I would have to agree with this 100%!

We have gone in the opposite direction regarding Squish/ quench from the gitgo and I believe it has everything to do with not only the repeated success we have had, but also the longevity............(ie. Wide and Forgiving tuning window )

[Dr. Johny Dodge]

interesting thread .. especially as I scored two ported heads just last week from a local shop that's closed
one G , one F-B

I'll have to wash up the F-B head and compare it to the pics but I think it may be a long way off from what I'm seeing here
from the quick look I had I think it hasn't been much more than smoothed

anyone have some good G head combustion chamber pics ?? - something from a known good performing head as that's something that could really help if I had something to
work from / copy /compare

[83scamp]

anyone have some good G head combustion chamber pics ?? - something from a known good performing head as that's something that could really help if I had something to
work from / copy /compare

See Warren's picture above. Doesn't get any better than that...

[glhs875]

See Warren's picture above. Doesn't get any better than that...

What he said!!!

[Shadow]

anyone have some good G head combustion chamber pics ?? - something from a known good performing head as that's something that could really help if I had something to
work from / copy /compare

I could show you pics of the G-head that's on the Charger IF I could find them. lol

G-head is easy though, for some simple basic flow........

Upon first glance they would appear Almost stock looking. At closer glance you would notice that the chambers have been enlarged to the size of the ID of the H/G firing ring and the "sides" of the "bathtub" have been laid back and opened up to promote flow. No where near the extent of Warrens head, hence the "stock" (albeit Larger dimensions) appearance.

[glhs875]

I could show you pics of the G-head that's on the Charger IF I could find them. lol

G-head is easy though, for some simple basic flow........

Upon first glance they would appear Almost stock looking. At closer glance you would notice that the chambers have been enlarged to the size of the ID of the H/G firing ring and the "sides" of the "bathtub" have been laid back and opened up to promote flow. No where near the extent of Warrens head, hence the "stock" (albeit Larger dimensions) appearance.

It would be interesting to see pictures of the heads being used by members.

[glhs875]

Here is a picture of mine. This head has been an experimental project and has lived a rough life!! LOL The head makes great power! Makes way way more power at higher boost levels than the 20psi max that was used for the time slip of my signature! If I were to ever build a new head I would want the combustion chambers to be more like Warrens.

[2.216VTurbo]

It would be interesting to see pictures of the heads being used by members.

I have a +1 swirl head at the shop right now that I will have back in a couple days. I'll take some pics next week. It started life as a TVL head that I had on Woody a couple years now it's finding a home on SmokeBox I mean RedBox I've done some reshaping of the chambers and ports after Tyler finished with it. To me it has *too much* removed from the chambers but he does great work so it's more cost/time effective than starting from scratch with a stock head. Im having new, valves, guides, and springs installed and I touched up the ports a little.

[OmniLuvr]

so alan, where did he take "too much" away from the chambers? I'm sure we will have pics soon, but I hate waiting...

[Dr. Johny Dodge]

thanks
Warren's head looks different enough I wasn't really sure what the heck I was looking at lol

it started with FB heads .. but the raised boss around the spark plug hole was making me think MAYBE it was a G head
the dimple opposite the plug had me wondering too

I guess that's where we get to the looks like half of each style

[Force Fed Mopar]

I've only ever run swirl heads, and stock ones at that with stock Garretts. But, I've had good luck with them so far, and have helped a couple others tune theirs with good results.

I've discussed it with 5DIGITS at length before, and my consensus is that when you start getting higher than 14 psi on a FB head, the swirl it induces is so fast that it starts becoming counterproductive. You end up having to pull more and more timing. Whether it's because the efficiency goes up and needs less timing, or the sharp edges of the chamber cause knock, or the heat of the charge goes up, or whatever, I'm not sure. I know that at around 20psi and up on my best tune, the timing drops to 1 degree total timing at spool-up and ramps back up pretty quickly after 4500, which is where the pumping efficiency starts to drop off. I have run up to 25psi on a stock FB with a stock Garrett and a awic system, but that is pretty much the useful limit of pump 93 octane IMO. I ended up going just as fast at 20psi as it did at 25 with some tuning, so 20-22 is pretty much where I'd stop on that combo.

Also, mileage was about 26-28mpg in normal country/town driving, and 34-35mpg on the interstate on a 2.5 in the Lebaron.

[5DIGITS]

I've only ever run swirl heads, and stock ones at that with stock Garretts. But, I've had good luck with them so far, and have helped a couple others tune theirs with good results.

I've discussed it with 5DIGITS at length before, and my consensus is that when you start getting higher than 14 psi on a FB head, the swirl it induces is so fast that it starts becoming counterproductive. You end up having to pull more and more timing. Whether it's because the efficiency goes up and needs less timing, or the sharp edges of the chamber cause knock, or the heat of the charge goes up, or whatever, I'm not sure. I know that at around 20psi and up on my best tune, the timing drops to 1 degree total timing at spool-up and ramps back up pretty quickly after 4500, which is where the pumping efficiency starts to drop off. I have run up to 25psi on a stock FB with a stock Garrett and a awic system, but that is pretty much the useful limit of pump 93 octane IMO. I ended up going just as fast at 20psi as it did at 25 with some tuning, so 20-22 is pretty much where I'd stop on that combo.

Also, mileage was about 26-28mpg in normal country/town driving, and 34-35mpg on the interstate on a 2.5 in the Lebaron.

Well said !!

[Shadow]

Here is a picture of mine. This head has been an experimental project and has lived a rough life!! LOL The head makes great power! Makes way way more power at higher boost levels than the 20psi max that was used for the time slip of my signature! If I were to ever build a new head I would want the combustion chambers to be more like Warrens.

Even your chamber is more extensively done than the Chargers. Although it's hard to tell if you got everything out around the tight sides where the firing ring of H/G meets the chamber walls.

Didn't take too many pics back when we did the head for the Charger and we have always kept things pretty simple. I did find this pic though, when I blew the H/G I snapped a couple pics and this was one of them.

[Shadow]

I've only ever run swirl heads, and stock ones at that with stock Garretts. But, I've had good luck with them so far, and have helped a couple others tune theirs with good results.

I've discussed it with 5DIGITS at length before, and my consensus is that when you start getting higher than 14 psi on a FB head, the swirl it induces is so fast that it starts becoming counterproductive. You end up having to pull more and more timing. Whether it's because the efficiency goes up and needs less timing, or the sharp edges of the chamber cause knock, or the heat of the charge goes up, or whatever, I'm not sure. I know that at around 20psi and up on my best tune, the timing drops to 1 degree total timing at spool-up and ramps back up pretty quickly after 4500, which is where the pumping efficiency starts to drop off. I have run up to 25psi on a stock FB with a stock Garrett and a awic system, but that is pretty much the useful limit of pump 93 octane IMO. I ended up going just as fast at 20psi as it did at 25 with some tuning, so 20-22 is pretty much where I'd stop on that combo.

Also, mileage was about 26-28mpg in normal country/town driving, and 34-35mpg on the interstate on a 2.5 in the Lebaron.

I agree with everything your saying and can concur that any larger turbo build than S-60 seemed to suffer greatly trying to make power at higher boost and the amount of tuning, or more accurately, Detuning, was ridiculous to say the least on the FB heads. (I've had several people insist on staying with the FB head because of what they read on the internet lol)

I have used stock FB heads with no larger than S-60 turbos up to 27psi and made power all the way up, but on race gas as they would never support that on pump. (full bodied 1990-91 Daytona 108mph trap speed)

Anything I would consider "built" we always went straight to the G-head because of flow and just a way more simple platform to work with.

Just like the 2 piece vs one piece intakes, we would pick up several hundred RPM of PB, just swapping out a stock FB for a stock G-head.(all about Flow)

This was with the understanding that we wanted to Increase the PB, knowing that, ultimately, it would be the Easiest route to making Big Power

So it all depends on what your objectives are.

What really makes things interesting, is the resent offering by 5DIGITS. At first I had thought that maybe Ken had figured out a way to get New code into the old system. (ie. Our modules, with features like Command AFR's where the O2 remains in the loop even under WOT conditions)

Looking at the direction of this thread makes me realize that IF your intention is to follow the Squish/quench way of thinking, well then I can clearly see why the need for Greater fuel and spark control above 54-5800rpm. (I did not see this because I have experienced no need in the case of the Charger)

As the tuning "window" becomes narrower, finite Control becomes much more crucial.

I have seen more people burn themselves down and/ or utterly Fail in a build by setting a low boost goal with ridiculous timing ect in an attempt to reach that goal. Maybe Kens new cal templates with birth a new era in the development of that ideology!

Or maybe I have No clue and just shooting in the dark! lol

Guess we will wait and see

[glhs875]

Even your chamber is more extensively done than the Chargers. Although it's hard to tell if you got everything out around the tight sides where the firing ring of H/G meets the chamber walls.

Didn't take too many pics back when we did the head for the Charger and we have always kept things pretty simple. I did find this pic though, when I blew the H/G I snapped a couple pics and this was one of them.

Yes, the sides of my chambers are worked all the way to the H/G area. I think our chambers look similar to one another. I prefer a G casting head for what goals I had. It would be neat to have a new casting made up from scratch that offers some of my ideas as well as the ideas from others as improvements!!!!