Dart Iron Eagle Heads

That is the total HP you can expect.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

40 thou deck clearance??yack...your machinist should of offered to zero deck it....

20 horse is 4 1 hundredths....



see other posts about the inefficiencies BEHIND the motor....


thats where you can kill some big ET and get that thing in the 14.70s or 80s....




al  

When I put my new heads on I am going to use a .015-.02 inch thick head gasket which will make the quench area around .055-.06 which is the best I can get with my engine without different pistons. Right now it has a .08 quench area, so .06 should be alot better.

So what you are saying is that .01 inch off your deck clearance is 5 horsepower.  

no...i was not clear,

on your time slip...20 hp is '4 one hundeths'...two decimal pointsover to the right

ex (just plugging numbers)

400 hp gets you a (example) 13.87 ET,420hp can get you a 13.83 or so....we are splitting hairs,but the gains from 70hp are not that huge...

on a 13flat car...putting a 250 shot of NOS typically nets you bout 7 tenths ET reduction and i say typically because traction, hence 60ft ET is the all time variable here....too many variables..but they pretty much all can be accounted for...


alan  

I found a different set of heads that might be better than the iron eagle I will list the specs for both

Iron Eagle                                 Edelbrock #61909

180cc intake runner                        170cc intake runner
77cc exhaust runner                        60cc exhaust runner
52cc chamber                               54cc chamber
valves 2.02/1.6                            valves 1.94/1.55
max lift .520                              max lift .600

Flow                                       Flow
intake 208cfm at .500 lift                 intake 252cfm at .500 lift
exhaust 175cfm at .600 lift                exhaust 192cfm at .600 lift


Which heads would be better for the 307.  

Stick with the iron eagles.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

Why the edelbrock give almost the same comression and they have smaller runners and valves and way out flow the iron eagles just there aluminum.  

What about the trick flow super 23 street heads with the 56cc chamber, 175cc/67cc runners, 1.94/1.55 valves and flow about the same as the edelbrock but still way better than the iron eagles.  

Well what ever heads you use just remember when going to a higher flowing head the  peak HP and torque will be at a higher RPM.
Also there is a such thing as the heads being too big (flowing too much) for a certain application and when that happens it will hurt the performance.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

Ok I think I have it, so your saying that the iron eagles are better for my applacation because they flow less cfm and the other heads flow to much cfm and would not help the power as much because they are to big and would kill the low end torque.  

Now you've got it your learning.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

Well then, Iron Eagles it is.  

Good luck on that head swap.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.

OK, thanks. Next weekend I am racing in a 1/8 mile bracket race and Im running 10.77 at 66MPH in the 1/8th when I let the car shift its self at 5000RPM at 60MPH, so when I run the 1/8th I will just pull it into low gear and run the full 1/8 in first gear, is there anything that I can do for very little money to make the car run faster. Like advance the timing or something like that, anything that will make it faster.  

What is the timing set at now.  
Professional hi-performance engine builder

Horsepower sells Engines and torque wins races.