I did a lot of pulls a few days ago and have some ??? The runs were made in 4th gear and IC temp's were monitered externally with a pyrometer and the runs started at +/- 3 deg. of the same temp. but most of the late runs fell off at high rpm. It was a mild day and I had lots of air flow parallel to the ground with the top edge of the fan at about the IC level blowing across and not down on it. Oil temps were not monitered and water only by factory gauge. The runs at the end of the day were also closer together as I was no longer changing SuperTrapp discs, just intakes. A/F was not checked either as I had no way to do it.

Could the fall off still be heat soak even though IC temps started the same?

Would running in 3rd gear help much? Would that throw the torque numbers off? I've seen a few results posted on MINI2 that showed less whp than I had but more torque and wondered if they ran in third. Would third also be better since I'm mainly interested in autocrossing, even though torque #'s may not compare fairly.

Am I correct that 1/4 mile runs can be done on the dyno?

I will be going back again in a few days and test in reverse order and post results in more detail then but best combo of software and intake with best SuperTrapp disc number was 189 whp and 167 ft/lb on a different combo of software and intake. I had my light weight wheels and tires on, 28-30 lbs. and they are 23" in dia. This was done on a Mustang 1750 DE

Big thanks to Mugami for lending me his intake and pyrometer doing the swaps and monitering the temps.

Edit. A few quick notes, went back again today, ran in third gear, tested everything again in reverse order, same IC temps at start, outside air apx. 8 deg. cooler, 94 octane instead of 93. I'm up to 196 whp and climbing @ 6850 where the dyno cut me off, later, and torque peak is now at 170 @ 3.8k. I now have a clear favorite between the 3 intakes and with which software. The Madness intake on stock JCW software beat every other combination, beating the JCW/JCW combination by an average (not peak) of 2.7 whp and 3 lbs. of torque over the last 1000 rpm. Over the whole tested rpm (2.9k to 6850) range it bettered the JCW/JCW by an average of 1.86 whp and 1.83 lbs. The Madness/JCW never lost any torque to the JCW/JCW and at only one rpm did it loose any hp and that was 1 whp @ 3.3K. From 2.7k down the JCW/JCW was the best, up 3 lbs. on average.

The combination of a slightly cooler day and 3rd gear cut apx. 20 deg. off my end of run IC temps. Mugami will probably correct this as he was doing the temps and it may have been more.

Well, I just got an alignment after the dyno and a new Webb Extreme bar, to my surprise I was at 1/2" toe out in front!!! I wonder how much power that cost me. Well it's off to the Peru Tour tomorrow.

 

Hello-
Please see my web page Dyno Warnings! Your fan setup is not adequate and it will damage your car. True dynos for forced air engines are run in wind tunnel conditions. Most all testing is done in the real world at a test track. Be careful.
Regards,
Don

 

I run in third gear, instead of 4th, since I don't have access to one that can simulate 110mph over the car. And, no I have one that does 90mph either, but with my following explaination you'll see why. Now why 3rd and not 4th? Both are really close to the recommended gear ratio of running a dyno run, at least in my 03 MCS they are...dunno about the new gear ratios. Secondly, I run 3rd so the dyno pull goes quicker and my car is under less stress without the proper airflow. This will also help alleviate some issues with heatsoak and detonation caused by extremely hot intake charges. I also make sure I have a fan blowing directly on my intercooler. Yes, I do this for every run. It's safer. I'd rather not be replacing my pistons because I do run around 25psi of boost which in and of itself is going to generate a tonne of heat and increased heat and/or increased boost can cause detonation. Detonation can lead to many bad things such as blown pistons. So to me it's worth it to keep my car safe as safe can be.

Some mustang dynos will allow you to do a 1/4 mile run, launching, shifting and all. FWIW, Mustang dynos tend to show lower HP than other dynos. On one dyno my car made 253whp, then a few weeks later on a Mustang dyno my car would only make 220whp. Big difference. As long as you understand that not all dynos do/show the same thing, you'll be just fine.

 

Conditions were perhaps better than I described as there are two hudge shrouded exhaust fans, at widnsheild level, at the rear of the 15x28 room and the front 28-30" fan is shrouded as well. This is where many of the local circle track and drag racers dyno their cars, as the dyno is rated to 2,000 hp.

 

i took my car for a dyno run when it was stock, and the mechanic put it in 5th gear instead of 4th. I got 121whp. Can anyone estimate how much it would've been in 4th?

 

Inexpensive dynos, such as a Mustang, with large fans blowing are not suffiencient for forced induction engines. That is why manufacturers don't use them -- they test in the real world. The air box is designed to run with pressure. Read the article I posted from Banks Engineering on my web site.

 

Nice reading and i do agree with most of it.. To add also to help with the heat problem we were spraying down the IC before the runs and keeping it soaked during the runs. which help with the charge going into the engine but never thought about the charge going into the SC itself. With the exception of the Stock intake the others we use were pretty much open air intakes and were in the front flow of the cooling fan. Still not a pressurized area. I did inform it wouldn't be the same as ON road. '

Something to Note in this area it's not easy to find a TEST track to do this on. So we do what we can for Grassroot testing. So far we can agree on the exhaust. We found for the Supertrapp. Having around 17-19 disc was the best combo for a JCW stock set up. We even tried full open which wasn't as good as the 17 disc set up. With the class Gowest runs in he is not allowed to touch the motor so we can only deal with Intake, Exhaust and programming.(ECU Flashes and Piggy back systems only). He has the Stock and UniChip. While im running MTH Standard file with SAFC-II. After a few more MODS coming soon ill be upgrading to the MTH tuner. to finish out the car. Currently im happy with the 205whp. with the next set im hoping for 215whp this include the Tuner file. Then its time to due the heads and cam profiles. Since i didnt want to touch the motor itself until the warrenty ran out two months ago =)

 

Bump, edited first post to reflect my second day of dyno info.

 

why should i correct anything. .. you correct on the IC number they were on avg 20-30 deg cooler today