BillP

I had my car in a dyno shop this last week, getting baseline runs as well as getting an SCT flash. The shop is Dynolabs (http://www.dynolabs.net) in San Ramon, CA. The owner is Ray Razon, and he's a good guy, and they work on a lot of Mustangs and Corvettes.

I'll post ALL the details later, but there were a few discrepancies in the spreadsheet I got from the shop, and I'll give them a chance to correct them before we publish the data. It was a cut/paste error, so we'll wait for the real stuff.

Bottom line: Hydrocarbon trap costs you 4-7hp across your power band!

The following information is run on 91 octane, SCT 91 octane flash, with factory exhaust (I've removed my Flowmaster Super40's, as they actually COST me 3-4hp across the board)

My car has a 5spd manual tranny.
Here is the rough data at 100rpm intervals: -->Dyno table

And here is the graph he provided me:

BillP

By the way, his dyno is a DynoJet.

If the 15% loss is accurate, my car is now running 325hp/350lbft on 91 octane.

The numbers for an 87 octane flash were darn close to the 91. I was a little underwhelmed with the increase on the 91, I'm sure there is more there, as 2005RedGT got 23hp out of his SCT tune. I think a second trip to the dyno shop is in order, down the road. The numbers for the 87 and the 91 were within a couple of HP across the board.

Bottom line: over 275hp at the rear wheels, a tick off 300lbft torque at the rear wheels. Nice.

Dan

Did you do a factory/stock dyno?

BillP

Ray didn't run it with the HC trap in place, stock tune, stock exhaust. My mistake, I brought the car over there with the HC trap out.

I'll post more info later, you can infer 4-7hp for the HC trap, stock or not. You can infer a couple of HP loss for the Flowmasters. The stock flash vs SCT 87 vs SCT 91 was done with the Flowmasters in place, and I'll post those after I clear up the aforementioned discrepancy in the data. I've asked Dynolabs for the raw data so I can compile my own spreadsheet from it all.

BillP

Here is more data.

This is from Flowmaster. This is their BASELINE run. This is WITHOUT the HC trap, with FACTORY mufflers, factory tune.

This is run on a different dyno, a Superflow. I don't know any more details about the dyno.

Flowmaster's Superflow Dyno, my 2005 Mustang GT

Notice how the horsepower peaks in the 5500rpm range, and torque peaks just above 4200? The numbers from Dynolab tend to not trail off as much, so the torque peak is still around 4200, but the HP numbers tend to flatten and keep high on their runs. I am not sure if the dynos are measuring differently at different RPMs or what. I know that some Superflows can be set to run with eddy current that simulates speed and weight differently than a Dynojet.

Dan

So 276rwhp and 290rwtq with flowmasters and no trap eh?

So, can I conservatively assume that the stock car is putting out the same values (removal of the trap and adding of the flowmasters cancelling out at the peak approx.)

With 12% losses its: 314hp and 330lb-ft (someone said ford quoted this as the %loss)

With 15% losses its: 325hp and 341lb-ft

I wonder which is closer?

BillP

No, the HC trap is 4hp at lower RPM, almost 7hp at peak RPMs. It costs you 7HP. The Flowmasters cost 2hp, less than 3 across the board.

And it ~really~ ~truly~ doesn't matter what the engine is putting out at the crank, as you can't drive a car without a drivetrain. It is what it puts to the road. And you can't compare my dyno run to another persons dyno run without a giant fudge factor.

My big deal is that the two runs I have for 87 octane tune and 91 octane tune were like 2hp off each other... meaningless (as two runs back to back can vary by 2hp easily due to engine cool down differences, etc.)

I think there was a problem with my tunes, I don't have the A/F ratios for them, so I am not convinced that they were cleaned up as much as possible. It looks like I gained 11 HP from the SCT 87 tune, and only 12 HP for the SCT 91 tune. But 2005RedGT got 23HP from the SCT 91 tune as modified by his tuner.

wild stray

M-1, good info, appreciate it! I still have to get a few more miles on mine before I try the tune, etc. I will attempt to do a good document job at that time.

2005RedGT

Great job, M1Rifle.

BillP

2005RedGT:

You and I are going to have to hook our tuners up with each other. THey shouldn't mind swapping tuning info if they are in CA and TX and don't share a common customer base.

PM me.

AFBLUE

The graph and one of the spreadsheets shows 276rwhp and the other spreadsheet shows 274rwhp.

Just curious what the difference is and does this mean that factory would be 262-264rwhp (You say you gained about 12rwhp overstock)

Sorry, I just got a little confused from the posts above.

BillP

Spreadsheets only cover 100rpm increments. Max can occur between the increments. Hence the difference.

But note! I only had spreadsheet data to 6000 rpm. The HP increases past 6000 rpm on this dyno run. Like I said, I have incomplete data (and in the case of the other runs, it looks like I accidentally got some data from one run cut/paste into data on another run). So the spreadsheets give only part of the picture.

Once I get all the dirty details (I've asked the shop for the raw data from the dyno runs), I'll tabulate them and we'll repost. Then we'll also be able to show factory mufflers vs. this particular Super40, and factory tune vs. SCT tune. Until I clear up the discrepancy in the other spreadsheet data, it doesn't make sense to publish it.

BillP

AFBlue-

I have runs with stock tune, flowmaster mufflers (which cost you about 2hp), and they are in the 261-262 peak RWHP area. I didn't show that data because I still have some questions for the dyno shop to clear up before I post them. My apologies.

The differences between stock tune and SCT tune were all done with the Flowmasters installed and the HC trap removed, because that's how I dropped it off at the shop. In retrospect, and if more dyno time was available, it would have been ideal to put it all back to stock (mufflers, trap, factory flash) and get a baseline. But it would be time consuming to do every combination, so we have to infer a little.

Dan

I agree, I was just curious by how much Ford underrated their peak crank values.

In a perfect world, magazine etc. would only list rwhp/rwtq numbers.

V10

But don't go only by M1s #s. There are going to be variations from one car to the next and from one dyno to the next. Some may have more power than M1's, while others will have less.

Thanks for posting all the info, M1.

Having the manufacturers go to RWHP may be a good thing. I'm sure as more and more high HP cars roll out, the government and safety groups are going to make a lot of noise. going to RWHP would make the #s look lower and most of those critics will never understand the difference.

Dan

But don't go only by M1s #s. There are going to be variations from one car to the next and from one dyno to the next. Some may have more power than M1's, while others will have less.

Thanks for posting all the info, M1.

Having the manufacturers go to RWHP may be a good thing. I'm sure as more and more high HP cars roll out, the government and safety groups are going to make a lot of noise. going to RWHP would make the #s look lower and most of those critics will never understand the difference. [/b][/quote]
I know there are variations, but every data point counts. With a few dynos one could establish an approximate range of true output.

Also, you'd think insurance companies would want to go to a rwhp system as well since there are so many car companies underrating horsepower numbers. Now, of course I'm not for that because it will mean higher rates. Insurance companies use actuarial science so in the end rates will depend more on claims than power output, but they have to establish a rate group/classify the car, so it does come into play.

Anyways, rwhp/tq would really make for more accurate comparisons between cars. The only possible problem is that you may get different values between manuals and autos. Do you list two sets of values? Probably for the average consumer not familiar with rwhp/tq, they would prefer the simplier crank hp, even if it is misleading.

On a side note, I wonder if the day will come where a computer will run your car down the quarter mile/0-60mph to allow for an accurate comparison between vehicles?

Kluski

Will running without the HC filter effect the car (other thant he horsepower aspect). I guess I am getting at; will it do any harm?

BillP

No. The HC trap is there to trap HC molecules that drift out after turning off the motor. This is to aid in the smog tests done for EPA and CARB, nothing more. If you are familiar with dessicants used for trapping moisture, the HC trap does the same thing, trapping HC and releasing it back to the intake charge later when the motor is on.

It's a hideous solution. It affects WOT numbers across the RPM range, not just as you approach readline.

Kluski

So if you live in an area that does emission testing for the state inspection, you should sneak it back in before the inspection, then take it our afterwards.

Does it just slide out?

BillP

Yes, put it back in for all inspections.

It doesn't just slide... there is a rubber lip (molded into the intake tube) that blocks it from "falling" out. You need to use rat nose pliers, and gently push the lip to the outside of the steel tube that is the body of the HC trap. Once you have massaged that lip all the way around the body, grab the HC trap by the steel outer body (NOT THE VANES!) and tug it out 1/8" on one side, then go around 90deg and do it again, repeat as necessary. After a few cycles, it will come out more than must that 1/8th or so, it gets easier as more of it comes out.

It pops back in much easier than it comes out. But getting it out is easy, just requires a little patience and 2 minutes with a set of pliers.