Dyno pull results

[mysleeper6]

Several people have touched upon this, (and justa4banger is the voice of experience) but what really has to be considered with dyno testing is improvement. Since every dyno posts different numbers, their only use (outside of ego-stoking) comes with using the same dyno to establish a baseline and then getting data from each modification (someone said it best: it's a tuning tool). And everyone seems concerned only about changes in peak horsepower: you should be looking at the entire area under the curve as a measure of improvement.

You also have to consider that no dyno directly measures horsepower. What is being measured is torque, or twisting power. Horsepower is then calculated from the torque measurement by the formula hp=(torque x rpm)/5252. I saw the original poster was concerned about the relationship of the torque and horsepower curves. A couple of observations. The dyno you were using may have been using a different scale on one or both axes, which could have accentuated the differences between the curves. However, by the formula, your curves (and every other dyno sheet's curves) should have interesected at 5252 rpm.

 

[BluMicaR]

Several people have touched upon this, (and justa4banger is the voice of experience) but what really has to be considered with dyno testing is improvement. Since every dyno posts different numbers, their only use (outside of ego-stoking) comes with using the same dyno to establish a baseline and then getting data from each modification (someone said it best: it's a tuning tool). And everyone seems concerned only about changes in peak horsepower: you should be looking at the entire area under the curve as a measure of improvement.

You also have to consider that no dyno directly measures horsepower. What is being measured is torque, or twisting power. Horsepower is then calculated from the torque measurement by the formula hp=(torque x rpm)/5252. I saw the original poster was concerned about the relationship of the torque and horsepower curves. A couple of observations. The dyno you were using may have been using a different scale on one or both axes, which could have accentuated the differences between the curves. However, by the formula, your curves (and every other dyno sheet's curves) should have interesected at 5252 rpm.

Okay, my curves did NOT intersect at 5252, what does that mean? They're near the end of page 2.

 

[Zimmer]

didn't read whole thread so don't rip me a new one .... but damn that's a hot & humid day .... anyone have a lot of experience with running at different ambient conditions in his thread?

as to the track i ran stock first time ever i wanted to break 15s stock i wanted to test my own driving skills see how good i really was... sure i didn't have the baddest car on the strip but i knocked almost a second of my time just learning to launch the car and shift at diff rpm, etc... not to mention the first time i went i had such an adrenaline rush i'm lucky i didn't stall !!!! LOL g'luck brotha don't get too bent over it

 

[techspeak]

get a fuel pump. your ECU will like you more and give you more top end knowing it can maintain the pressure

 

[mysleeper6]

Okay, my curves did NOT intersect at 5252, what does that mean? They're near the end of page 2.

Woah. That is interesting, and I had to spend some time looking at other dyno sheets to make sure my math wasn't f*'d. Anyone else want to chime in on this? My first thought was the SAE correction, but even in that case there should be some value for rpm that equalizes torque and horsepower. Strange, but I'm not gonna stick my neck out and say it's wrong. Let me look at your sheets for a bit, and in the meantime maybe someone will bail me out!

 

[ericrapp]

Fuel pump?

get a fuel pump. your ECU will like you more and give you more top end knowing it can maintain the pressure

why not bigger injectors?

 

[mysleeper6]

Just pulling out 2 obvious points from your dyno sheet torque curve has left me even more confused. Look at your torque at 4000 rpm. Although its a little hard to read, it looks like you are making 320 ft. lbs. of torque. That should convert to 243 hp, but your chart reads around 210. At 5252 (where torque and horsepower should be equal) you are making 260 ft. lbs. which converts to (one to one relationship) 260 hp. I was skeptical at first but now I think there is something screwy with your sheet. Am I wrong?

 

[Vord]

why not bigger injectors?

bigger injectors won't help if our fuel pump can't pump enough fuel to keep up with the engine mods already.

the pump itself is the restrictive part.

 

[BluMicaR]

Just pulling out 2 obvious points from your dyno sheet torque curve has left me even more confused. Look at your torque at 4000 rpm. Although its a little hard to read, it looks like you are making 320 ft. lbs. of torque. That should convert to 243 hp, but your chart reads around 210. At 5252 (where torque and horsepower should be equal) you are making 260 ft. lbs. which converts to (one to one relationship) 260 hp. I was skeptical at first but now I think there is something screwy with your sheet. Am I wrong?

I thought there was something screwy given my mods. In my OP I said my buddy with an SRT-4 said these guys at this shop are nimrods. I didn't know them from Adam, it was just an impulse purchase upon seeing a tuner shop next door to Midas when I was in there to have Midas fix a donut in my exhaust. I'm betting their nimrods. I also found out why my turbo wasn't spooling high; if everyone has followed my 'have a variant manifold, need the variant kit to fix IC-turbo hose rubbing manifold' issue. My IC hose burnt through; I thought it was okay, but last night heard too much air sound and threw a CEL. Sure enough, quarter-size hole in the hose. New one on and you know I'd swear this thing has been leaking a little for a long time, including when I was on the dyno. My boost pulls to 18 then settles in 4th/5th/6th like it is supposed to now. I am going to try and smash my old tube in the scanner later...

I'm going to Antioch/N Chicago July 4th weekend; I am going to see if Ken can't get me in for a just-numbers dyno then to have non-retards log me.

A bad scan but you get the idea: this is the original IC to turbo inlet hose, it's about 4.5" on the inside of the bend, 5.5" on the outside. The hole is about the diameter of a quarter.
View attachment IC a HOLE.pdf

 

[Supermex]

Gents a word of experience being passed on...... unless you get a baseline on a dyno and then use that EXACT SAME dyno to measure your mods you will never know what mods made what hp.

Now for my SVO i did over 40 pulls in a month and a half. i was testing cams for a guy. i have my baseline runs with a setup and then i change the cam and ran the dyno, rinse, repeat..........7 more times. this is the best way to see your gains on a dyno. with that said, i used a dynojet dyno that has a HISTORY of reading a wee bit low when compared to other dyno's. But i have the proof Plus the time slips to back up the HP the SVO was making. the 438whp in the sig is every bit true....... not shabby on a 30+year old engine design with cast crank and rods.

This dyno graph shows the difference in power, with different mods, for my SVO in the course of a year. i didn't have the final dyno graph to add in (438whp) but its close enough .

That's good info and a lot of dyno runs LOL
And WOW what a BIG difference in numbers.
My personal goal is 400+ to the wheels daily.

I like to point out that there where other MS3's being dynoed the same day, and it was interesting to see how others compare.
We did get a close to base line as possible on car # 1
Here are the final results:
MS3 #1 bone stock
MS3 #3 COBB port unit, BOV, CAI and cat back exhaust
MS3 #7 COOB SRI test pipe and Greedy exhaust, BOV,and bigger TMIC
MS3 # 8 was mine w/ CAI and cat back

The best of 3 passes on Dynojet, no tuning, was very hot and humid.

 

[Vord]

I thought there was something screwy given my mods. In my OP I said my buddy with an SRT-4 said these guys at this shop are nimrods. I didn't know them from Adam, it was just an impulse purchase upon seeing a tuner shop next door to Midas when I was in there to have Midas fix a donut in my exhaust. I'm betting their nimrods. I also found out why my turbo wasn't spooling high; if everyone has followed my 'have a variant manifold, need the variant kit to fix IC-turbo hose rubbing manifold' issue. My IC hose burnt through; I thought it was okay, but last night heard too much air sound and threw a CEL. Sure enough, quarter-size hole in the hose. New one on and you know I'd swear this thing has been leaking a little for a long time, including when I was on the dyno. My boost pulls to 18 then settles in 4th/5th/6th like it is supposed to now. I am going to try and smash my old tube in the scanner later...

I'm going to Antioch/N Chicago July 4th weekend; I am going to see if Ken can't get me in for a just-numbers dyno then to have non-retards log me.

A bad scan but you get the idea: this is the original IC to turbo inlet hose, it's about 4.5" on the inside of the bend, 5.5" on the outside. The hole is about the diameter of a quarter.
View attachment 133068

After considering Sleeper6's comments and doing some research on my own about these weird dynos. You need to go back and ask for your money back. I still think your AFR is too high, and the power dyno makes no sense. I ran some numbers and they dont have a right alteration factor. by this i mean, most dynos are (Tq*RPM)/5252, which is why they always intersect there.


at 4k I got 318 tq, 205 hp. plugging in backwards you get 6204 as the scaling factor.

at 3k I got 275 tq, 135 hp. Scaling factor: 6111

at 5k I got 275 tq, 225 hp. Scaling facor: 6111

at 6k I got 181 tq, 178 hp. Scaling factor: 6101.

so pretty much this dyno is saying HP= (TQ*RPM)/6111. 6111 is simply an estimate as the graph is slightly hard to read.

What this means is absolutely nothing. Its just a bad dyno, or they are way off in calibration or something, or they modified their scaling factor. I dont work with dynos so I dont know what is customizable about their programs.

 

[ericrapp]

bigger injectors won't help if our fuel pump can't pump enough fuel to keep up with the engine mods already.

the pump itself is the restrictive part.

I will pm you please for data thanks. Blue keep us updated. I have heard of some shops up our way that really did not have a good handle on tuning or even monitoring turbo cars. Hope all works out well.

 

[Supermex]

bigger injectors won't help if our fuel pump can't pump enough fuel to keep up with the engine mods already.

the pump itself is the restrictive part.

Does anyone knows at what point our injectors will max out?
What size injectors comes with stock?
And finally is there an aftermarket pump available for the MS3?

 

[Vord]

yes there are. CP-E has one.

http://www.cp-e.com/2111.html

Mrlilguy will have more info on this as he has done the most about it. If you want to find out more, you can search for his post or maybe PM him.

ProtegeGarage has one also. and they give a link to www.mrlilguyCDFPs.com

http://siteground207.com/~protegeg/product_info.php?cPath=160_395&products_id=1294

Now don't hold me on this, but I don't think anyone has maxed our injectors, or atleast I havent heard about it. cp-e, I THINK, (notice how i capped that) has claimed theirs will be good for 450-500+ hp. I don't remember were I read it and its not on their site, so don't hold me to it, its been a while. None the less, they have gotten at minimum 450 hp on it. I don't know if this was tested or is projected or if it was tested on some kind of testing machine. Generally, CP-E is open about their research and they back up products 150%. If you check the site and info. isnt there, call em' they will be glad to share its limits and how they found them out.

I do know that our pump is more restrictive than the injectors.

Hopefully the thread maker wont be mad for this short thread-jack. If anyone else has questions on my info. please PM me.

 

[Supermex]

Thanks Vord, I'm looking into it.
All this is related to the topic

 

[Hapa88]

dyno dynamics always show lower than competitive systems (mustang, dynapack, dynojet)

What correction factor did they use?

A friend of mine has a Dyno Dynamics dyno and he can make any car read any number. In fact my NSX dynoed at 211whp on the first pull, he changed that factor and the second pull was 248whp (exactly the same graph shape).

People don't seem to understand that Dynos are tools and not all of them are calibrated to the standard. There are tons of variables. About all a dyno is good for is telling you how much change there was between one run and another.

 

[BluMicaR]

After considering Sleeper6's comments and doing some research on my own about these weird dynos. You need to go back and ask for your money back. I still think your AFR is too high, and the power dyno makes no sense. I ran some numbers and they dont have a right alteration factor. by this i mean, most dynos are (Tq*RPM)/5252, which is why they always intersect there.


at 4k I got 318 tq, 205 hp. plugging in backwards you get 6204 as the scaling factor.

at 3k I got 275 tq, 135 hp. Scaling factor: 6111

at 5k I got 275 tq, 225 hp. Scaling facor: 6111

at 6k I got 181 tq, 178 hp. Scaling factor: 6101.

so pretty much this dyno is saying HP= (TQ*RPM)/6111. 6111 is simply an estimate as the graph is slightly hard to read.

What this means is absolutely nothing. Its just a bad dyno, or they are way off in calibration or something, or they modified their scaling factor. I dont work with dynos so I dont know what is customizable about their programs.

Can you point me somewhere more specific or give me some verifiable info I can take in and argue with this sumbitch?

 

[mysleeper6]

After considering Sleeper6's comments and doing some research on my own about these weird dynos. You need to go back and ask for your money back. I still think your AFR is too high, and the power dyno makes no sense. I ran some numbers and they dont have a right alteration factor. by this i mean, most dynos are (Tq*RPM)/5252, which is why they always intersect there.


at 4k I got 318 tq, 205 hp. plugging in backwards you get 6204 as the scaling factor.

at 3k I got 275 tq, 135 hp. Scaling factor: 6111

at 5k I got 275 tq, 225 hp. Scaling facor: 6111

at 6k I got 181 tq, 178 hp. Scaling factor: 6101.

so pretty much this dyno is saying HP= (TQ*RPM)/6111. 6111 is simply an estimate as the graph is slightly hard to read.

What this means is absolutely nothing. Its just a bad dyno, or they are way off in calibration or something, or they modified their scaling factor. I dont work with dynos so I dont know what is customizable about their programs.

Good work Vord. The thing is, they should be using 5252 because that is the rpm at which hp and torque are equal. That number was derived by James Watt. He decided (or determined) that one hp was equal to 33,000 foot lbs. per minute (kind of arbitrary). If a one pound weight on a one foot fulcrum is allowed to rotate 360 degrees, 6.2832 ft lbs of work has been done (circumference of the circle times the one lb). Dividing 33,000 by 6.2832 shows that that one pound weight must rotate at 5252 rpm to equal one hp. So, if they aren't using 5252 they aren't registering in the terms Mr. Watt intended them to.

Here's a good link with more theory regarding dynos.
http://www.vettenet.org/torquehp.html

 

[Vord]

Can you point me somewhere more specific or give me some verifiable info I can take in and argue with this sumbitch?

I don't mean to be a dick, but any mechanical engineering based physics book will do the job. this is a standard, a SAE NET HP is measured as such, at the wheels or not doesnt matter. If its a big deal, I would take him to the better business burea, there is no arguement here that his dyno has a incorrect correction factor. This may not be illegal, but it seems fraudulent to me. Although in your case, it wasnt trying to make you look better, it still is a cause for concern as dynos are used to correct mistakes, and find issues with cars (like detonation and even in some cases, as yours, you are trying to figure out if you have a "power" leak or if its the dyno). I haven't ran the TQ numbers with a proper correction factor, but it seems like your TQ numbers are on par with the mods.

Take the car out to a drag strip and run it a few times, get a nice 60-ft time and compare it to other numbers with similar mods. if you cant get a good 60-ft time, I will run my car from 40-80 and give you a specific time and you do the same and we can get another car to do 40-80 (hopefully one with similar times). Testing a car doesn't require alot of complicated work, its making sure that you arent ******* something up that is a problem.

 

[Vord]

What correction factor did they use?

A friend of mine has a Dyno Dynamics dyno and he can make any car read any number. In fact my NSX dynoed at 211whp on the first pull, he changed that factor and the second pull was 248whp (exactly the same graph shape).

People don't seem to understand that Dynos are tools and not all of them are calibrated to the standard. There are tons of variables. About all a dyno is good for is telling you how much change there was between one run and another.

The issues here isnt what dynos are used for. The issue is that he feels he is leaking power somewere and we are trying to figure out if there is a real loss in power or the dyno is ****** up.

Now obviously the dyno is ****** up, what is left is to make sure his car is working properly without any turbo leaks or fuel cuts or detonation (thats my concern as I still think his AFR is high. I dont know much about AFRs and tuning, but no one has given me a solid answer as to why his AFR is 14+ in low RPM). If he runs another dyno, we know s*** is working fine. If he finds a good dyno place, atleast they maybe able to test for leaks or detonation or whatever concern he has.

sorry for my long-winded answers, but its a serious topic!!