afr engine combo
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I never advocate building motors piecemeal. Usually costs you more in the long run. You don't want advice so I'm not gonna offer any.
Ratio, the line between single planes and dual planes is getting very blurry. I see a lot of dyno tests and the best dual planes make power up top just like milder singles, and milders singles aren't giving up much down low to the more radical dual planes. Different engines with different cams respond differently, of course, but it's a horse apiece at this point. I know your a big advocate of milder singles planes, but good dual planes are right there.
Ratio, the line between single planes and dual planes is getting very blurry. I see a lot of dyno tests and the best dual planes make power up top just like milder singles, and milders singles aren't giving up much down low to the more radical dual planes. Different engines with different cams respond differently, of course, but it's a horse apiece at this point. I know your a big advocate of milder singles planes, but good dual planes are right there.
reenmachine
Dirt-Old 20+Year Member
Not to be picky, but torque is not power, it is torque. Mathematically, they are two entirely different things.ratio411 said:
Horsepower makes you go fast, torque gets you to that speed quickly. To quote an old adage, "horsepower sells cars, torque wins races."
ratio411
Founding Member
Not to be picky, but you have it backwards.reenmachine said:
Torque is a measure of power.
Horsepower is a measure of time.
Torque is the power attained, and HP is how fast it can be made.
If torque won races, a diesel couldn't be beat in the quarter.
I have 500 ftlbs of torque in my Powerstroke, but only 210 hp because it is slow and steady torque.
That is what I am getting at... you build everything for torque and you won't get your et.
There must be a balance.
Dave
Max Power said:
hey sorry if i offended you, i didn't mean too. what i meant to say is i'll eventually get the rpm and bigger cam but I have the heads off any ways and that's all I can afford right now. I WILL put the better parts on later but I just can't right now. sorry if that came out offensive. Alright after looking around i've pretty much decided i need alot of suggestions. I like the brodix, afr, tf, ptl and rpm heads. a plus i see with iron PTL's is that I could afford to upgrade my intake while i'm at it. now i am asking for advice and my bad about earlier maxpower
ratio411
Founding Member
I ran the numbers through the PC and got:
315/325 as listed 94% volumetric efficiency
322/329 with RPM intake 95%
329/330 with Stealth 96%
These are just modeling numbers, but they are based on airflow etc...
So they give an idea.
I am going to play with 185s now...
Btw: 185s shouldn't cost much more...
Ported stock heads flow 155.
Edit:
185s
Stealth
Everything else the same...
337/337 99% VE
Remember that peak torque is not the concern for a street engine, average torque is more accurate:
Original combo: 247 ft/lbs average
Last combo: 270 ft/lbs average
This means that throughout the power range, the gain is 23 ft/lbs.
I would also like to note that there is no way I know of to model Tri Ys, so all have been 1.5" primary LTs.
315/325 as listed 94% volumetric efficiency
322/329 with RPM intake 95%
329/330 with Stealth 96%
These are just modeling numbers, but they are based on airflow etc...
So they give an idea.
I am going to play with 185s now...
Btw: 185s shouldn't cost much more...
Ported stock heads flow 155.
Edit:
185s
Stealth
Everything else the same...
337/337 99% VE
Remember that peak torque is not the concern for a street engine, average torque is more accurate:
Original combo: 247 ft/lbs average
Last combo: 270 ft/lbs average
This means that throughout the power range, the gain is 23 ft/lbs.
I would also like to note that there is no way I know of to model Tri Ys, so all have been 1.5" primary LTs.
ratio411
Founding Member
Go with the 165 cc AFRs, the 185s have 2.02 intake valves, you would probably have to fly cut the pistons, lowering compression even more. The 165s will make very decent hp numbers. You can always pick up the intake later and it is fairly easy to install. You could always pick up a used one for a little savings.
Dave, I'm running Tri-Y's on the 331 stroker in my Ranger, there's NO loss of power with them. This 3800 lb, aerodynamics of a brick, 89 Ranger runs mid 13's with them, thru the mufflers, on street tires. My Canfields are probably the equivalent of the AFR 165's, same sized valves (1.94/1.60) They flow around 270 with the .587 lift cam I'm running on the intake and around 200 on the exhaust side. With the same heads on a 5.0 short block and a B303 cam (1.7 rockers), the motor would pull to 7500 with them. On the 331, all I push it to is 6500, no need to go higher. Plus the 331 has way more bottom end (starts to pull at 1500 instead of the 5.0's 3000) than the 5.0 they were on had. After running the 331, I'd much rather have the bottom end than stressing the motor up at the top end of the rpm range. He'd never miss the 185's on a 302 short block with the 165's and a good dual plane intake. Sure the 185's will make more power, but it'll be at the upper end of the rpm range,ratio411 said:
reenmachine
Dirt-Old 20+Year Member
Not to be picky....well, OK, now I gotta be picky. Sorry to get all "engineer" on you:ratio411 said:
Torque is not a measure of power. It is a force that tends to rotate or turn things. Its units are (force)*(distance), e.g. foot-lbs. That is, one ft-lb is defined as the moment, or "twisting force" created by applying a force of one lb. at the end of a 1-foot lever arm.
Horsepower is a measure of time???? So, if someone asked you how long it took to get somewhere, you could say, "oh, about 72 horsepower"???
Power (e.g. horsepower) is a measure of how quickly work can be done. The units of power are a unit of force multiplied by a unit of speed, or a combination of torque and rotational speed. For example, a force of 1 Newton on a 1-meter lever arm gives you a torque of one Newton-meter (N-m). Multiply that by rotational speed and you get power in Watts. Of course, the same holds in English units; 1 horsepower = 746 Watts.
You can put a torque of 200 ft-lbs on a breaker bar, but can you spin that 4000 times a minute? That's the difference between torque and horsepower.
OK, lecture aside, you are basically right.ratio411 said:
It's just a matter of terminology, and I'm an anal-retentive engineer so terminology is sacred to me. Of course "performance" is a combination of horsepower and torque, and there must be a balance, as your example demonstrates. You wouldn't want to try to tow your car trailer with a Peon SRT-4 even though it has the same horsepower as your Powerstroke either.Anyway, let's let dude get back to his engine discussion.
Don't take this the wrong way, but I believe that you should get the heads first, but dont install them yet. Wait until you get the new cam and intake too. Its like you can't have one with out the other. I mean if your heads allow for a lot of air flow but your cam and intake will not allow for this flow, there is no point in doing the install yet. Save yourself some time and wait. You will end up spending extra time for all of the same parts you had to take off for each. You will end up taking each part off twice unsead of once. Those gaskets can get expensive, and you will have to mess around with timing twice instead of once. That can take a while if done correctly.
WantaGT said:
No worries!
Heads are where most your power is made, and they are also the biggest pain to swap out, so if you must go piecemeal, get heads first. Heads are becoming a replacement item these days anyway, with the cost of porting and good valve work.
You will be limited to the 1.94/1.90 intake as stated above. If you follow Hearnes advice and get a brand that isn't trendy right now (read AFRs), you may just be able to afford tha cam and intake anyway.
I went with Performer RPMs and they are a good head for the money. There are others, and most are very good. Just make sure you get a head that will clear the pistons.
I have no experience with Pro Topline, so I can't comment. Brodix are a respected name, but I personally haven't used them. I would be comfortable buying them.WantaGT said:
I bought my RPMs from a friend of a guy at Edelbrock, so I got the deep deal. $995 is a good price for them, and I love the steel inserts in all the bolt holes. I also like that everything is in the stock location.
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