Some real V8 Dyno #'s to compare

65coupei6

65coupei6

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My club recently had a Dyno Day. I wasn't able to attend but here are some rear V8 numbers to compare against some numbers other inliners have post for their 6's. Most people always think V8 with 300hp+. But, unless you are talking pro drag cars they really do not get up there.

86 SVO 4 cyl. 180.3 rw 225.3 torque 207.3 flywheel (stock)
03 Mach 1 278.8 rw 306.7 torque 320.6 flywheel. (Yes, it is under rated at the factory for insurance reasons :) )
69 BOSS 429 284.8 rw 341.3 torque 327.5 fly (stock)
67 289 242.1 rw 258.6 torque 278.4 fly (4-barrel)
67 351C 263.3 rw 287.5 torque 302.8 fly (4V head, long tube headers, x-pipe, Holley 4-barrel)
65 289 170.2 rw 239 torque 195.7 fly (mild mods)
67 351C 205.7 rw 261.6 torque 236.6 fly (2V heads, 4 barrel, headers, had ignition problems)
93 Cobra 226.6 rw 275.6 torque 260.7 fly (stock)
70 BOSS 302 235.4 rw 254.7 torque 270.7 fly (stock)
03 GT 232.3 rw 274.1 torque 267.1 fly (stock, 154 MPH on Dyno)
84 SVO 4 cyl. 221.7 rw 252.8 torque 255 fly (ported head, T3/T4 turbo, ported exhaust manifold, roller cam)
65 289 144.8 rw 202.8 torque 166.5 fly (4-barrel, GT exhaust)
92 Miata 331 Stroked Windsor 230 rw 268 torque 264.5 fly (Get's sidways on the Freeway when you stomp on it! Fun to ride in :) )
69 March 1 351C 292 rw 388 torque 335.8 fly (Drag Car!)
 
I had a dodge shelby charger....with a cam and compueter chip went from 160hp stock to I think 202...

I miss that car

i dont know why I felt I had to tell you all that now....sorry for the hijack...

:shock:
 
I'm delighted man. Some good news for you. Talk to your mates about this.

The flywheel figure is not 1.15 times the rwhp figure. A set of car tires on a dyno soak up twice the hp as a stock set of tires because of the contact area is often in two postions. It could be argued that if the contact area is doubled, the load on each is halfed or even quartered as the front wheels are not being pushed etc, but roads aren't made of steel, and chip seals, stone mastic asphalt and conrete are not like steel either.

For an auto, use 1.333 times the rwhp to get net flywheel hp. A C6, FMX will soak up more than that, perhaps 1.36. AOD's are quite good, as there is no torque convertor slip. C5's are almost as good as a T5 speed. If its not warmed up, then you loose much more than that.
Click to expand...

For a T5 manual, use 1.265 times the rwhp to get net flywheel hp.
Click to expand...

Sources

These figures come from Wheels Magazines from 1977 to 1981, Brads Speed shop, COME engineering, Ford Australias well publicised 1993 Mustang Cobra engined Falcon GT hp barney and some of Street Machine Australias tests over the last 13 years.

I've seen a British race car manual list 15 to 17% due to drive train losses, but they don't include tire losses, a glaring ommision virtually no-one except Pommy Race engine developers like APT pick up on. It really upsets me when a guy gets rwhp figures, and then only adds 1.15 to get net installed. At 100 mph on a dyno, there is over 10 being parasitically stollen due to heat and friction on a set of 235/60 14 tires. Then a lot of autos slip up to 3 % on a dyno since they don't warm up.

Then the dyno man gives you rwhp verses speed graphs because they don't like to do calcs for fear of scaring the customer into thinking he's cooking the bookes. The SAE correction for baraometric pressure and air isn't often done right, and the dyno calibration needs to be current.

Here's my slant on your figures. The speed at which the maximum power was at changes rolling resistance, allong with tire section. Not bold figures.These are conservative!

86 SVO 4 cyl. 180.3 rw 228 hp SAE net
03 Mach 1 278.8 rw 375 hp SAE net
69 BOSS 429 284.8 rw 360 HP SAE net
67 289 242.1 rw 306 hp SAE net
67 351C 263.3 rw 333 hp SAE net
65 289 170.2 rw 215 hp SAE net (manual?)
67 351C 205.7 rw 261.6 torque 236.6 fly (2V heads, 4 barrel, headers, had ignition problems)
93 Cobra 226.6 rw 286 hp SAE net (manual?)
70 BOSS 302 235.4 rw 298 hp SAE net
03 GT 232.3 rw 274.1 torque 267.1 fly (stock, 154 MPH on Dyno) Oh yeah, thats probably 20 hp worth of rolling resistance right there! 293 SAEnet hp may be 303 hp or more!

84 SVO 4 cyl. 221.7 rw 280 hp SAE net
65 289 144.8 rw 183 hp SAE net
92 Miata 331 Stroked Windsor 230 rw 268 torque 264.5 fly (Get's sidways on the Freeway when you stomp on it! Fun to ride in ) 291 hp SAE net
69 March 1 351C 292 rw Shift kitted FMX or C4/C10? 370 hp SAE net.

I'm prepared to argue the toss. Theres lots of info to draw on!

Be encouraged. Some dynos read low, and people get saddened 'cause they could pay a few bicks and get a high reading dyno, get lied to and feel better even though there car could be very strong in the first place.

Here is a link on a cool 289 Cougar, sent by kind forum freak :wink:. The poor owner was worried because he only got 140 or so rwhp on the rollers. In fact, if its auto, he has more than 186 hp at 4000 rpm, and much more if the dyno man was prepared to rev it. If the auto was cold, the power could have been 200 hp at 4000 rpm.

The torque figure, if measured in second gear in an auto is at 2500 rpm, rather too low. This is 410 lb-ft at the flywheel, but needs to be divided by the torque multiplaction factor, 1.40 or so for second gear in a V8. That's about 290 lb-ft. This indicates enough to get 240 hp netSAE at the flywheel. The package is little different to an 84 5.0 HO engine, similar 600 cfm carb, just a little less capacity and a wilder mechanical cam.

This guy has been cheated out of power because, in my opinion, the dyno runs didn't cover the entire rev range. There are some questions over the low torque speed, and certainly, the operator was covering his safety obligations by buttoning off past 4000 rpm. A little 289 loves revs! 5500 rpm or 6500 rpm with a mechanical cam.

I'm pleased that the dyno runs state the facts, and look entirely truthfull.But you know, how would you answer a very high torque reading good enough for a mild 351W, and 351W 2-bbl like power at only 4000 rpm? Its got more power at 5000 rpm, I'll bet!
http://www.fordmuscle.com/phpBB/viewtopic.php?topic=13921&forum=16&10
 
Marco said:

here are some rear V8 numbers to compare against some numbers other inliners have post for their 6's.Most people always think V8 with 300hp+. But, unless you are talking pro drag cars they really do not get up there.
Click to expand...

This could be taken two ways....

1) AHAHAHHAHA that's funny look at all those V8 thinking they're hot stuff, but the turbo fours have almost the same output :lol: :lol: :lol:

2) AWWWW man!!!! :cry: :cry: If V8's put out numbers like that, what's my little six gonna look like.... :( :( :(

BTW here's a link on this same matter (sort of )
http://www.mustangandfords.com/techarticles/5216/

Alex
 
Alex: That is basically what I was trying to get across.

1) People with V8's think they are hot stuff and always slam on imports. But, alot of the imports with 4 cyls. and 6 cyls. make decent power just like the 4 cyl SVO.
2) Some people also think that our 6's can make V8 HP. I don't know about that.

XECUTE: That's good info. Thanks. I will pass along the info to the owners of those cars. They will be happy.
 
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