18 degree heads
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
18 degree heads
Anybody go the 18 degree heads yet, I'm sure someone has, but I probably missed it.
For my fall project,,, I'm tossing around the idea of 434 w/18 degree heads, single plane plane intake with @ 80mm throttle body intake,
For my fall project,,, I'm tossing around the idea of 434 w/18 degree heads, single plane plane intake with @ 80mm throttle body intake,
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,062
From: altered state
St. Jude Donor '05
I wish!
think there is a guy here with that same setup name escapes me (stevexxx?)
Pretty stout setup
Hes a regular sure he will post
think there is a guy here with that same setup name escapes me (stevexxx?)
Pretty stout setup
Hes a regular sure he will post
Last edited by cv67; Jan 22, 2012 at 10:06 PM.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
I cant see a reason to build , just another 434, it needs some spice, although every component involved with 18-degree heads costs more, I have no problem in making this a piece by piece process.
Less than 5 miles from me is an excellent Cylinder Head resource, so that part would be easy, and I would thoroughly enjoy welding up my own header tubes
Less than 5 miles from me is an excellent Cylinder Head resource, so that part would be easy, and I would thoroughly enjoy welding up my own header tubes
Safety Car
Joined: Feb 2000
Posts: 4,564
Likes: 109
From: Austin Texas
Your engine @ 7K RPM's NEEDS 1,758 CFM. That would be about 280 CFM per cylinder.
A set of Brodix 23 deg. T1 M2's like I have flow 309 CFM's.
To convert to 18 deg. heads?
Custom Intake
Custom Headers
Both will cost you a BUNCH of money.
23 deg. intakes & headers?
LOTS of choices.
EASY decision...
Safety Car
Joined: Sep 2001
Posts: 4,149
Likes: 547
From: Glenbeulah Wi
Not too sure why you would WANT to go that route.
Your engine @ 7K RPM's NEEDS 1,758 CFM. That would be about 280 CFM per cylinder.
A set of Brodix 23 deg. T1 M2's like I have flow 309 CFM's.
To convert to 18 deg. heads?
Custom Intake
Custom Headers
Both will cost you a BUNCH of money.
23 deg. intakes & headers?
LOTS of choices.
EASY decision...
Your engine @ 7K RPM's NEEDS 1,758 CFM. That would be about 280 CFM per cylinder.
A set of Brodix 23 deg. T1 M2's like I have flow 309 CFM's.
To convert to 18 deg. heads?
Custom Intake
Custom Headers
Both will cost you a BUNCH of money.
23 deg. intakes & headers?
LOTS of choices.
EASY decision...
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Not too sure why you would WANT to go that route.
Your engine @ 7K RPM's NEEDS 1,758 CFM. That would be about 280 CFM per cylinder.
A set of Brodix 23 deg. T1 M2's like I have flow 309 CFM's.
To convert to 18 deg. heads?
Custom Intake
Custom Headers
Both will cost you a BUNCH of money.
23 deg. intakes & headers?
LOTS of choices.
EASY decision...
Your engine @ 7K RPM's NEEDS 1,758 CFM. That would be about 280 CFM per cylinder.
A set of Brodix 23 deg. T1 M2's like I have flow 309 CFM's.
To convert to 18 deg. heads?
Custom Intake
Custom Headers
Both will cost you a BUNCH of money.
23 deg. intakes & headers?
LOTS of choices.
EASY decision...
Bending air on a 434 for an optimum performance is always a challenge, hence the SB2 / 18-degree heads. Also, my local shop M&M Competition Engines, @ 2 miles away makes SB2.2 exclusively
18 degree will make for HP than 23 degree on performance engines , that's a fact, fast cars are expensive, that a fact as well.
Safety Car
Joined: Feb 2000
Posts: 4,564
Likes: 109
From: Austin Texas
It is not this simple. A 434 is definitely air flow limited and the better flowing the head the more power it will make (assuming a high performance build and not a low RPM stocker). At 100% VE a 434 will need 879 CFM (4 stroke has 1/2 the power strokes that you calculated) but since the head only has a limited amount of time to get air into the engine the better the flow the more power potential. A general rule of thumb is that a head that flows 309 CFM can support 632 HP and on a 434 it will peak HP at 6250 RPM if the correct parts are chosen. If you want peak HP to occur at 7000 RPM on a 434 you need cylinder heads that flow 350 CFM at 28in of depression.
That's a fact...my engine builder has done half a dozen of them, and dynoed every one of them. Mine will be built to run E85, so the compression ratio will be in the 12.5:1 range to get the most out of the octane rating of the fuel.
My calculations were a bit off, and after looking at it closer I posted this in another thread...
For my M2 T1 227's, each port on the intake will need to be able to flow 309 CFM to not starve the cylinder.
A V8 engine gets a power stroke every 90 degrees: 720° ÷ 8 = 90°, which is four power stokes for each revolution of the crankshaft.
So in a single revolution, you have at least 4 cylinders filling with air simultaneously (but 90 deg. off of each other). 309 x 4 = 1,236 CFM
A V8 engine gets a power stroke every 90 degrees: 720° ÷ 8 = 90°, which is four power stokes for each revolution of the crankshaft.
So in a single revolution, you have at least 4 cylinders filling with air simultaneously (but 90 deg. off of each other). 309 x 4 = 1,236 CFM
And I couldn't agree more about costs. It seems that you spend cubic dollars to get small gains sometimes...but you have to spend it.
It'll be interesting seeing the results of your project...
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
All of the work on my first 3 engines was done here before the owner Bob, sold it to guys that used to work at INDY Cylinder Head, which is a premier MOPAR performance shop. i.e. Top Fuel etc.
http://mmcompetitionengines.com/
Last edited by LD85; Jan 23, 2012 at 11:06 AM.
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Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Spoke to my buddy at M&M, he says that a SB2.2 using Edelbrock Pro Port Heads, (they used to use the GM-011 heads) would cost $12k-$13k with me doing the assembly but with them blue printing the setup,,, and using a single plane EFI, tall deck block Dart Iron block, and hyd-roller, pump gas, 434CI.
I asked him for a ballpark power estimate and he said that he would "feel safe in saying @ 660-FWTQ and 675-FWHP range" , take it for what its worth
So, I'm stuffing the piggy bank and gonna put a freeze on gun purchases, my other hobby
and go out and sale Automation Equipment like I never have before!
Today its a dream and I hope some tie after Thanksgiving, its a reality.
I asked him for a ballpark power estimate and he said that he would "feel safe in saying @ 660-FWTQ and 675-FWHP range" , take it for what its worth
So, I'm stuffing the piggy bank and gonna put a freeze on gun purchases, my other hobby
and go out and sale Automation Equipment like I never have before! Today its a dream and I hope some tie after Thanksgiving, its a reality.
Race Director
Joined: Jan 2008
Posts: 16,027
Likes: 170
From: oregon
reading all this..can see the draw to 18deg heads, but, if you're going to do the fab work wouldn't using a turbo be almost smarter? you can set the hp level anywhere you want, can maintain a hyd valvetrain and do not need any trick engine parts..except a very solid bottom end and if possible inconel exhaust valves.
something like
http://www.youtube.com/watch?v=cccYWADbHPw
would not be all that hard to do
and another in action
http://www.youtube.com/watch?v=bpP20...eature=related
something like
http://www.youtube.com/watch?v=cccYWADbHPw
would not be all that hard to do
and another in action
http://www.youtube.com/watch?v=bpP20...eature=related
Last edited by racebum; Jan 23, 2012 at 06:41 PM.
Melting Slicks
Joined: Mar 2002
Posts: 3,108
Likes: 126
From: S.L.C. UT
The AFR 235's flow in the 340cfm range, and the AFR 245's flow in the 350cfm range, both 18 degree territory. And they use off the shelf 23 degree stuff, although the 245's require a shaft system.
Safety Car
Joined: Sep 2001
Posts: 4,149
Likes: 547
From: Glenbeulah Wi
The 245's should work well and save some money.
Racer
Joined: Oct 2007
Posts: 478
Likes: 1
"The AFR 235's flow in the 340cfm range, and the AFR 245's flow in the 350cfm range, both 18 degree territory."
I know what everyone is saying but I think there is more to this from my experiences. Comparing my motor to the LSX series I am down 30+ horsepower. Here are my stats.
1) 369cubes
2) 11.12:1 compression ratio
3) 280/280-233/233 camshaft on 113 LSA, .594" lift at valve.
4) AFR 210 heads modified by DR J., Flow 305cfm at .600" lift on his bench. Speed at the pushrod pinch is 315fps. 2.08/1.60 valves.
5.) Intake flows 336 cfm with maximum with max airspeed of 300fps at peak horsepower rpm of 6500rpm.
Everything is there and the best I can do is 420rwhp/417rwtq. If this was an LSX combination with the same exact specs I would be well past 450rwhp. IMHO I am thinking that the 18 degree and 15 degree heads utilize the available CFM better in creating horsepower. In other words it is much easier to make the power with the 18/15 degree heads than the 23 degree heads. I am still wrestling with this and found this thread quite interesting as I am looking into it myself.
I know what everyone is saying but I think there is more to this from my experiences. Comparing my motor to the LSX series I am down 30+ horsepower. Here are my stats.
1) 369cubes
2) 11.12:1 compression ratio
3) 280/280-233/233 camshaft on 113 LSA, .594" lift at valve.
4) AFR 210 heads modified by DR J., Flow 305cfm at .600" lift on his bench. Speed at the pushrod pinch is 315fps. 2.08/1.60 valves.
5.) Intake flows 336 cfm with maximum with max airspeed of 300fps at peak horsepower rpm of 6500rpm.
Everything is there and the best I can do is 420rwhp/417rwtq. If this was an LSX combination with the same exact specs I would be well past 450rwhp. IMHO I am thinking that the 18 degree and 15 degree heads utilize the available CFM better in creating horsepower. In other words it is much easier to make the power with the 18/15 degree heads than the 23 degree heads. I am still wrestling with this and found this thread quite interesting as I am looking into it myself.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
IMHO I am thinking that the 18 degree and 15 degree heads utilize the available CFM better in creating horsepower. In other words it is much easier to make the power with the 18/15 degree heads than the 23 degree heads. I am still wrestling with this and found this thread quite interesting as I am looking into it myself.
The best engines I can recall reading about always seemed to have hi CR, and the ones that had crazy good numbers, well, I was always suspicious of those.
At this point, i.e. today, I don't see myself spending $12k but the engine in my car has probably only @ 10k miles on it, so I am in no rush, I'll read and study about this more, lots to consider, hood height and clearances etc.
The only custom part is the headers as far as I can see, everything else is off the shelf, although the heads are ported by a CNC , just as many others are. So off the shelf yes, and costly yes
yes!
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Also, I agree that there are less costly options, if I had to do it on today's budget, I would buy a Dart SHP block ($1500) or Little M, and then throw my forged 406 parts into it, and add a blower or SC.
Safety Car
Joined: Sep 2001
Posts: 4,149
Likes: 547
From: Glenbeulah Wi
"The AFR 235's flow in the 340cfm range, and the AFR 245's flow in the 350cfm range, both 18 degree territory."
I know what everyone is saying but I think there is more to this from my experiences. Comparing my motor to the LSX series I am down 30+ horsepower. Here are my stats.
1) 369cubes
2) 11.12:1 compression ratio
3) 280/280-233/233 camshaft on 113 LSA, .594" lift at valve.
4) AFR 210 heads modified by DR J., Flow 305cfm at .600" lift on his bench. Speed at the pushrod pinch is 315fps. 2.08/1.60 valves.
5.) Intake flows 336 cfm with maximum with max airspeed of 300fps at peak horsepower rpm of 6500rpm.
Everything is there and the best I can do is 420rwhp/417rwtq. If this was an LSX combination with the same exact specs I would be well past 450rwhp. IMHO I am thinking that the 18 degree and 15 degree heads utilize the available CFM better in creating horsepower. In other words it is much easier to make the power with the 18/15 degree heads than the 23 degree heads. I am still wrestling with this and found this thread quite interesting as I am looking into it myself.
I know what everyone is saying but I think there is more to this from my experiences. Comparing my motor to the LSX series I am down 30+ horsepower. Here are my stats.
1) 369cubes
2) 11.12:1 compression ratio
3) 280/280-233/233 camshaft on 113 LSA, .594" lift at valve.
4) AFR 210 heads modified by DR J., Flow 305cfm at .600" lift on his bench. Speed at the pushrod pinch is 315fps. 2.08/1.60 valves.
5.) Intake flows 336 cfm with maximum with max airspeed of 300fps at peak horsepower rpm of 6500rpm.
Everything is there and the best I can do is 420rwhp/417rwtq. If this was an LSX combination with the same exact specs I would be well past 450rwhp. IMHO I am thinking that the 18 degree and 15 degree heads utilize the available CFM better in creating horsepower. In other words it is much easier to make the power with the 18/15 degree heads than the 23 degree heads. I am still wrestling with this and found this thread quite interesting as I am looking into it myself.
I am not sure what your goals are but your combination could benifit from a cam with a tighter lobe seperation and more duration. It will idle rougher but it will hit harder and make more power if the cam was changed.
Safety Car
Joined: Sep 2001
Posts: 4,149
Likes: 547
From: Glenbeulah Wi
My heads on a 427 make 750 HP and 695 lb./ft.
That's a fact...my engine builder has done half a dozen of them, and dynoed every one of them. Mine will be built to run E85, so the compression ratio will be in the 12.5:1 range to get the most out of the octane rating of the fuel.
:
That's a fact...my engine builder has done half a dozen of them, and dynoed every one of them. Mine will be built to run E85, so the compression ratio will be in the 12.5:1 range to get the most out of the octane rating of the fuel.
:
A rule of thumb is (intake flow X .256 X 8 = HP potential of a high performance street car), (intake flow x .280 x 8 = HP potential of a competition built engine designed for racing with limited on no street use), (intake flow x .311 x 8 = HP potential of an all out drag race engine, no compromises)
HP street (309 x .256 x 8) = 633 HP
Competition (309 x .280 x 8) = 692 HP
All out, no compromises (309 x .311 x 8) = 769 HP
These are rules of thumb and should only be used as that.