Coffee&Cars
Well-Known Member
Maybe this will help, from Muscle Motors...... .257 x no. of cylinders x flow @ 28"
example-- .257 x 8 x 410 = 843 hp.
example-- .257 x 8 x 410 = 843 hp.
Max horsepower with EQ heads?
- Thread starter gregsdart
- Start date
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Coffee&Cars
Well-Known Member
My Cruster on the left has EDDY RPM heads, ported by me, has stock 45 degree valve seats and 2.14 intake valves on a 493 stroker 440, 273 Degrees at .050 and .625 lift. Best time to date is 10.29 @131 mph. Don't know the flow but I am happy with it.
I don't know who cooked up that formula, but i have done better, and others have done better yet.
528 cube wedge, Indy 440-1 heads, single four intake, 15/1 compression, max flow of the heads was 368 at .750 lift, which was the net lift of the cam. This motor has pushed a 3065 lb car to 8.77 at 153 mph, and the 60 ft was slow by .05 on that pass. That was in about 2,000 da air to boot. So the dyno hp should be about 880? For corrected hp. From the experiances of a very well known engine builder, there is another 30 hp at least if I go to a tunnelram intake. That works out to over 900hp with an improved version of a "stock" NON RACE (what ever that means!) Head that has too little cross sectional area for the rpm it runs. The data logger shows 7450 rpm on the shifts and 7500 in the lights. Peak hp is at 6900, by the way. The car slowed .03 when i tried to drop the shift points to 7250.
I see that some don't get the idea behind this post- the point is, what could be had for power out of these EQs without major expense beyond big valves and a full port?
Sure, this combo i cooked up in my head won't make max power at 7200. That is my safety margin. I would expect peak power at maybe 6700, and with a TR intake the motor would probably like a 7,000 shift point.
When i first data logged my car, i was surprised to see the true shift rpm of 7450. I have the airshifter set at 7200, it takes another 250 to complete the shift! So things often aren't as they appear, aand we never know as much as we think we do!
Someone mentioned something about the combo doing better with less stroke? I have run the same basic heads on 475, 499, and 528 cubes, and picked up power everytime i went bigger, all with heads that are "too small". I doubt it is much different with these heads.
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And maybe this will help further.......
My 451 stroker with Edelbrock RPM heads flowing 349 cfm made 787 HP for 2.255 hp/cfm. My 500 wedge made 848 with 370 cfm for 2.292 hp/cfm.
Your formula says he will only make 614 HP and I can only get 718 & 761. I like the way he and I calculate it.
Coffee&Cars
Well-Known Member
That formula comes straight out of HP Books, Big-Block Mopar Performance written by the guy who owns the Muscle Motors shop.
Heck of a big difference between your cubic inch and intake port cross sectional area ratio between the 528/440-1 combination and the 408/EQ combination. The 528 shouldn't get to choke rpm until about 7,300 rpm and the 408 will get there at 5,500 rpm. Now, if you can find another 1 square inch of cross sectional area in the EQ head I think you could get 650 HP. But 3.00 square inches in that head isn't going to happen without serious modifications.
So, my answer to your original question is 590-610 horsepower.
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So what would the choke rpm be on a standardport big block 906 iron head be? Heads were ported, gasket matched to a regular port size intake. The motor is/ was 535 cubic inch.
Brian Hafliger
Well-Known Member
Take a look at this...not a full on "kill" build, but a good effort build....How to Make 600 HP with Cast-Iron Heads on a Mopar 340 Stroker
moper
Well-Known Member
"the point is, what could be had for power out of these EQs without major expense beyond big valves and a full port?"
I still think 2.3 x the max flow will get you close given the attention to detail, gas porting, vacuum pump, etc etc etc. Leave the big block comparisons behind. We're talking a 4" stroke small block. "Major Expense" will be in the fitting of valvetrain you want (and would need) to theoretically reach your goal figures. Plus this is a race car - for that extra expense you get an extra 40-50lbs on the nose at no extra charge. As Scotty would say "You canna change the physics, Caaptain..."
I still think 2.3 x the max flow will get you close given the attention to detail, gas porting, vacuum pump, etc etc etc. Leave the big block comparisons behind. We're talking a 4" stroke small block. "Major Expense" will be in the fitting of valvetrain you want (and would need) to theoretically reach your goal figures. Plus this is a race car - for that extra expense you get an extra 40-50lbs on the nose at no extra charge. As Scotty would say "You canna change the physics, Caaptain..."
Not enough information. I know what the smallest cross sectional area of a 440-1 is and the smallest cross sectional area of the EQ heads I have here, but I don't know about the heads, particular gasket and intake that was used in your case. To me it is doubtful the engine would make any more horsepower at 6,500 rpm than it did at 5,500 rpm.
I know you are aware of this, but for those watching along, choke doesn't mean quit winding, but, not making more horsepower as it rev's. It's sucking all the air it can through that port restriction. No more air, no more horsepower, no matter how tight you wind it. But if you are making 600 horsepower, that could hang on for awhile and the vehicle would keep accelerating.
Very well, go do it. You've convinced me.
Krooser
Building Chinese Free Engines since 1959...
I don't think those EQ heads will support over 525HP from what I've seen... just won't flow enough. Nothing wroung with them...
My ported W2's flow 280 and the HP was 575 with the original set-up it had... ported M-1 intake, 580 lift cam, 13.5 to 1, 3.79 stroke, 4.030 bore... yada yada yada.
My ported W2's flow 280 and the HP was 575 with the original set-up it had... ported M-1 intake, 580 lift cam, 13.5 to 1, 3.79 stroke, 4.030 bore... yada yada yada.
There are similar formulae out there, the variable is the aggressiveness of the valvetrain action & it's control. Most of these are based on a fairly(but not extremely) mech.
flat tappet camshaft profile. Not max velocity .904 dia. based with high ratio rockers, not mushroom tappets, not rollers. The output factor goes up with these as long as
the springs/pushrods/etc. are up to actuating & controlling this high rate. Similarly, the velocity in a head is going to limit flow as IQ52 said, the more efficient a port is,
the higher this can be. But the viscosity of the fluid(air&fuel) will eventually develop sufficient friction that, for lack of a better "visual", the boundary layers "swell" up &
start "closing" the effective flow area of the port. Bigger engines demand more and the port velocity for a given RPM is automatically higher, so if the port CA can't handle
6K, it does little good to equip the engine with a 7K combo..........................
Brian Hafliger
Well-Known Member
Something seems wrong here...I made 560HP with my W2's over 13 years ago with a 360, 12.25:1, solid FT cam, victor 340, TTI 1 7/8 headers...by chance are you running a small header tube? Just curious, as you should be at 600HP unless your using a 700cfm carb.
famous bob
mopar misfit
Interesting! Never heard that formula before. Is it accurate ? According to it, my 440/505 street motor makes 723 . Happy w/ that. Car weighs 3278 w/ half tank of lawnmower gas (91) oct. , 3;73 gears, What will it run ? Anybody !!!!!!!!!!!!!!!!
famous bob
mopar misfit
-sorry about jackin the thread !
Bob, you might as well start a thread with a lot more info. Full engine and chassis specs. I will look for it and giv you a guestimate. Greg
moper
Well-Known Member
I got you on the Megablock Greg...lol. I guess if you're already pushing that around it is a bonus...lol.
Again to IQ's point on "winding"... Torque is measured force. Horsepower is that force over time. So even if the choke point creates a limit of the amount of air in the engine may still rev higher if there are no pumping losses and if each firing event is so much torque, the more events in a minute will always bring more horsepower. Right up until it doesn't. That's why I mentioned the smaller stroke earlier. Less expected pumping losses.
Again to IQ's point on "winding"... Torque is measured force. Horsepower is that force over time. So even if the choke point creates a limit of the amount of air in the engine may still rev higher if there are no pumping losses and if each firing event is so much torque, the more events in a minute will always bring more horsepower. Right up until it doesn't. That's why I mentioned the smaller stroke earlier. Less expected pumping losses.
That's a nice rocker setup! How did it setup pattern-wise OOTB?
Moper, it also makes sense to me that a better tuned system (tunnelram) will enhance the most important part of the induction cycle- the overlap period. Any thing that can be done to help that event would help carry power higher sincé the pressure differential can be up to five times that of peak lift.
famous bob
mopar misfit
Seems like I`ve typed this a lot lately. Don`t mean to be tooting my horn! ----------------------- 440/505, 10.3 c.r. , .620 lift solid street roller, alum victor knock offs/ flow 352 @ .600 , but don`t go up much from there. 1200 CFM throttle body/fast 2.0 , 727 fully auto, dana 60/3:73 Detroit locker, 2' tti w/ full 3 1/2" exhaust/dumped in front of rear axle , caltrac system, w/ 295 65 15 draq radials for the street (gas mileage), have (28" tall drag radials for the strip ??) 6 point cage/ subframe conn. , motor plate , alum. water pump housing, alum. crossflow rad., mech. fan/ with elec booster if needed. 68 fastback weighs 3278 w/ 1/2 tank 91 oct., cheeta shifter in stock console, 4 wheel manual disc brakes. Recip.assem. race balanced by hughs engines, absolutely no vibration . Have a reworked torquer 2 on it, but am reworking a weiand team G for comparison later, team G has a huge plenum, good for stroker, but has terrible scatter n 2-7 runners( working on that !) running a 4x14 filter, or I would be running a victor intake/ not enough room. Not completely broken in yet, and still tuning (plugs black) 6 pack scoop sealed to throttle body. prostars all around.
famous bob
mopar misfit
whew !
RAMM
Well-Known Member
You're absolutely right that a GOOD tunnel will add 30-40 HP over most good single 4 set ups. J.Rob
The problem with the 525 HP theory is that RAMM has already blown that number out of the water.
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