Dynoed my 427so Cobra today.... interesting to say the least!

[Excaliber]

Man thats gotta make the heel\toe thing a real bear...

[John McMahon]

...personally, I never even noticed it when driving.

I don't know how tall Keith is or if this is his first Cobra or not, but the pedal thing is just "one of those things" you need to get used to in a Cobra.

While the setup varies from manufacturer to manufacturer, I think we have all had to adjust to the pedals being off center left from a normal driving position.

[neverwouldof]

Originally Posted by Excaliber

Man thats gotta make the heel\toe thing a real bear...

Heel/toe driving is impossible.... i'm going to try and get it set up differently. I'm 6'2 and it has a dropped box in it. but my left knee is still crammed between steering wheel and door sill. Fred must have had short legs or been no taller then 5'10. Also going to have seat position moved 1.5" back which is far as it will go.

[DAVID GAGNARD]

Went to a Mustang Club car show today, brought my race car and my daughter drove my 65 Fastback and I entered it under her name, I only go to 2 or 3 "local" cars shows a year and this is my favorite........good folks and everyone has a good time, great club, they make everybody feel "like family"..........

Well, anyway, they had a couple of guys there with a chasis dyno and was charging 25 bucks a run........it was the kind on wheels (big trailer looking thing) about 6 or 7 feet off the ground.......they probably dynoed 6 or 8 cars and after the judging I tried to get my car on it, been wanting to chasis dyno my car since it has been finished.........well, it did not happen, ramp was too steep and my header collector flanges hit and I needed another 2 inches of clearance to get it up there, we tried adding some boards under the tires, but could not make it work............

So I'm interested in some results and watch them dyno 4 cars, the results were very suprising to say the least.........

Cars 1 thru 3, all 05 Mustang GTs, all 3 bone stock except for maybe a K & N air filter, that's it..........all 3 made from 262rwhp to 267 rwhp, they are adveritsed at 300 flywheel hp!!!!!!!!!!!! that's from 13% to 11% driveline loss, I think either Ford "fudged" those #s a little or else the driveline is very efficent.............

Now the kicker, car 4; 1969 Mach I, 428 Cobra Jet motor, I think these were rated at around 335hp to 350hp???? not sure........anyhow the owner said this motor had about 500 miles on it since a complete rebuild, he added Edelbrock alum heads,headers,big loud Flowmaster dual exhaust,850 cfm Holley, more cam??? not sure how much, not extremely wild, but better than the stock cam, electronic ignition.........now this motor was not an all out motor, but a "healthy" motor, which he estimated to make about 450 hp at the flywheel, never been dynoed, just his estimate, which could be achieved with what he had in the motor.............he ran it up to 6500rpms each of his 3 pulls............

Pull # 1, why he started from a dead stop in 4th gear, I'll never know, but he did, not very good #s, don't remember the exact #, but the owner said it had to be wrong.....I thought the motor loaded up real bad and he probably fouled the plugs some..........

Pull # 2; pretty much the same as # 1, except he starts out before they had the laptop ready and got some wierd readings, so they discounted the whole run.........

Pull # 3; operator told him to start in second gear and do the pull in 3rd gear, again, have NO CLUE why they would do it this way, but they did, I was standing near the rear of the car watching the driveline, he was running WAY,WAY rich by now, both exhaust pipes looked like a diesel truck going up a steep slope loaded down,he made 272 rwhp!!!!!!!!!!!!! when he shut it down and the operatpr showed him the #s and the printout, he was pi$$ed and told them to unhook the car and guide him down......they had a few words and he left, was only charged for 2 runs.........

Later talking to the operator he told me the "average" loss he has seen for late model cars with a stick shift was 15%........

The old Mach I was running a 4 speed toploader and 9" rear end with 3.89 rear gears, he had on a set of drag radials and as I was watching the rear of the car of his last pull, I did not see any signs of his tires slipping or spinning on the drums.........he had a very badly tuned motor, no doubt, but still thought he should have made from 350 to 375 hp at the wheels, he was about 100hp off............

Looks like I will not get a chance to do my car as those portable units are just to steep for my low sitting car............

I was very surprised at the low % of loss for the 05 GTs and very suprised at the high? % loss for a 428 Cobra Jet motor, sure thought it would have done a lot better.............

PS: almost forgot, I took second place with the race car and my daughter took a first place with the Fastback, boy was she proud!!!!!!!!!!!we had a great time together and I think she may be turning into a full fledged waxer now...........

David

[clayfoushee]

Originally Posted by DAVID GAGNARD

Went to a Mustang Club car show today, brought my race car and my daughter drove my 65 Fastback and I entered it under her name, I only go to 2 or 3 "local" cars shows a year and this is my favorite........good folks and everyone has a good time, great club, they make everybody feel "like family"..........

Well, anyway, they had a couple of guys there with a chasis dyno and was charging 25 bucks a run........it was the kind on wheels (big trailer looking thing) about 6 or 7 feet off the ground.......they probably dynoed 6 or 8 cars and after the judging I tried to get my car on it, been wanting to chasis dyno my car since it has been finished.........well, it did not happen, ramp was too steep and my header collector flanges hit and I needed another 2 inches of clearance to get it up there, we tried adding some boards under the tires, but could not make it work............

So I'm interested in some results and watch them dyno 4 cars, the results were very suprising to say the least.........

Cars 1 thru 3, all 05 Mustang GTs, all 3 bone stock except for maybe a K & N air filter, that's it..........all 3 made from 262rwhp to 267 rwhp, they are adveritsed at 300 flywheel hp!!!!!!!!!!!! that's from 13% to 11% driveline loss, I think either Ford "fudged" those #s a little or else the driveline is very efficent.............

Now the kicker, car 4; 1969 Mach I, 428 Cobra Jet motor, I think these were rated at around 335hp to 350hp???? not sure........anyhow the owner said this motor had about 500 miles on it since a complete rebuild, he added Edelbrock alum heads,headers,big loud Flowmaster dual exhaust,850 cfm Holley, more cam??? not sure how much, not extremely wild, but better than the stock cam, electronic ignition.........now this motor was not an all out motor, but a "healthy" motor, which he estimated to make about 450 hp at the flywheel, never been dynoed, just his estimate, which could be achieved with what he had in the motor.............he ran it up to 6500rpms each of his 3 pulls............

Pull # 1, why he started from a dead stop in 4th gear, I'll never know, but he did, not very good #s, don't remember the exact #, but the owner said it had to be wrong.....I thought the motor loaded up real bad and he probably fouled the plugs some..........

Pull # 2; pretty much the same as # 1, except he starts out before they had the laptop ready and got some wierd readings, so they discounted the whole run.........

Pull # 3; operator told him to start in second gear and do the pull in 3rd gear, again, have NO CLUE why they would do it this way, but they did, I was standing near the rear of the car watching the driveline, he was running WAY,WAY rich by now, both exhaust pipes looked like a diesel truck going up a steep slope loaded down,he made 272 rwhp!!!!!!!!!!!!! when he shut it down and the operatpr showed him the #s and the printout, he was pi$$ed and told them to unhook the car and guide him down......they had a few words and he left, was only charged for 2 runs.........

Later talking to the operator he told me the "average" loss he has seen for late model cars with a stick shift was 15%........

The old Mach I was running a 4 speed toploader and 9" rear end with 3.89 rear gears, he had on a set of drag radials and as I was watching the rear of the car of his last pull, I did not see any signs of his tires slipping or spinning on the drums.........he had a very badly tuned motor, no doubt, but still thought he should have made from 350 to 375 hp at the wheels, he was about 100hp off............

Looks like I will not get a chance to do my car as those portable units are just to steep for my low sitting car............

I was very surprised at the low % of loss for the 05 GTs and very suprised at the high? % loss for a 428 Cobra Jet motor, sure thought it would have done a lot better.............

PS: almost forgot, I took second place with the race car and my daughter took a first place with the Fastback, boy was she proud!!!!!!!!!!!we had a great time together and I think she may be turning into a full fledged waxer now...........

David

David, I've been wondering the same thing lately. I had always expected 20-25% loss as standard. When the new Z06s showed up advertised as 505HP, I was shocked to see most getting 450 RWHP bone stock, some a little more, some a little less, but a whole bunch of them very close. So many have been tested by owners, it's not a fluke.

Only 11-12% loss is amazing in some modern cars, assuming, of course, the advertised ratings were not understated.

[ByronRACE]

13-15% is normal drivetrain losses for a typical modern rwd manual transmission Ford. And by modern, I mean about 1985 and later. That loss was confirmed on multiple occasions using a superflow engine dyno and a dynojet chassis dyno at Mustang Ranch in Santa Clara, CA.

260+rwhp for a new manual transmission Mustang sounds about right. My 03 4.6L Marauder daily driver with the slushbox pulls 250rwhp on a dynojet 248.