SIR TEST RESULTS

[Ron Earp]

How about using a single dyno and running the same car with and without restrictor within minutes of one another? I'd love to oversee one of those tests.

Hey, I'll cover the costs if anyone wants to bring their BMW to the Dynojet in Raleigh NC. Haywood's Custom Speed shop, used it a number of times for various street cars as well as IT cars. $100 an hour, no limit to pulls for the hour. I'll pay, you bring the car well-prepped BMW 325, you bring the SIR. Think there are more than a few top running candidates in the area. I'll be there, Jeff Young will be there, and any other local IT'er that wants to check it out. Be an interesting test conducted by a non-involved indivdual(s).

R

[lateapex911]

OK, guys, I am almost finished shoveling, so.....

First, the CRB is on your side. They are not going to make any decision that could endanger the competiveness of the E36. If it means pushing back the implementation date, then they are open to that. I like your comment DJ, about radicals and rationals. What I saw this weekend was the CRB being very rational, and bending over backwards to get this resolved properly. I know that we got off on the wrong foot with the timing and the lack of data.....the CRB and the ITAC agree, and are going to attend to those issues.

Second, this is a tricky bit of business, as has been pointed out. Where do results come from? If I had MY way, I would hire Sunbelt to build me a top notch legal motor, and then go testing, with lots of SIRs, application parts, and on every dyno I could find. I would end up with a ton of data points and a lot of confidence in my final decision.

But this is the real world. So we are relying on an effort that is being put forth by members of the CRB, the ITAC guys, and actual competitors, like yourselves. Obviously, it's a difficult process, and to some degree, judgement and trust are part of the formula.

So, we are pressing forward with an evolving plan to aquire as many data points as possible.

This weekend was a major step, and we got to do some good back to back to back testing of various setups, and we owe a debt of gratitude to a competitor and a CRB member who opened his personal shop up for the day so we could make noise and burn gas.

One downside to the testing is that we are using real guys and real cars, and their privacy needs to be respected when requested. Another is that of course, no two dynos are created equal. Another reason we are trying to get many data points.

We have scheduled another test this coming weekend, with a different car, and a different size SIR, then, the weekend after that, we will be back at it with more SIR sizes, plus the ones already tested for repeatability, and at this point it looks like we will have the car we tested this weekend, AND another car.

At that pont, we will have a better picture, and can make more decisions. I have a further plan in mind, but I am not sure of it's liklihood, as it is rather ambitious.

I hear what you guys are saying about repeatabilty, legality concerns, and so on, and I assure you that we will do the best we can. I can promise that the effort will be far and above anything IT has ever seen.

Now, I know you want data and numbers, but at this point I can't release them. I can say that we see the need to do more testing, as the numbers that we have gotten so far from various sources are not showing the repeatability that is desired.

This is a process, and we are at the begining, with much more to come.

The dyno used in this test was a Clayton, a roller based chassis dyno. It uses lighter rollers, and the standard procedure is to bring the car up to speed, then drag it down, gradually increasing the load. It will not be the only type used, as we have scheduled testing on other makes as I mentioned above.

Stay tuned!

[dj10]

The dyno used in this test was a Clayton, a roller based chassis dyno. It uses lighter rollers, and the standard procedure is to bring the car up to speed, then drag it down, gradually increasing the load. It will not be the only type used, as we have scheduled testing on other makes as I mentioned above.

Stay tuned!
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Jake, From what i know, correct me if I'm wrong, the 2 most common dynos are dynojet and mustang? I heard mustang dyno read low and dynojets read high. If we are to shoot for a target hp reading wouldn't we need to use 1 or the other or both if we have a conversion scale. NASA uses all dyno jet and uses a 14.5 weight/hp ratio. Maybe this is the way to go?.
Having seen the results Jake, I think you should post what ever results you have BUT PLEASE also post your conclusions as well. You just told us you want to do another test we will abide by that. I'd like to see your pictures if you have any.
Thanks
dj

[lateapex911]

Well, good points on the different dynos, and we are aware of them, and we would love to run the full set of tests on all of them, LOL. Sadly practicality does enter the equation, but the results will be interpolated, and testing on different types of dynos is part of the plan. And DJ, not just one more test, but many more pulls. We did about 4 or 5 hours on Saturday.

Ron, back to back has already been done, and will be done again, numerous times. I like your offer! I encourage any and everyone to take Ron up on it.

Pictures! I forgot! lets see what I have...
The first pic it the opening, then the exit. The third is a view of the assembled unit, the sizing insert is alongside.

hmmmm. picture posting issues..lets try that again.

odd...i have done this before with success...but it isn't working now.

[mlytle]

Oh, pardon me; did I wander into the Bimmerworld Forums again by mistake...?
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that would be the bimmerforums, and geez, i hope not!

[lateapex911]

LOL......yeah, been there, done that, never agian!

they win the prize!

[Ron Earp]

Jake, From what i know, correct me if I'm wrong, the 2 most common dynos are dynojet and mustang? I heard mustang dyno read low and dynojets read high
dj
[/b]

This is essentially correct. The Dynojet reads higher than the Mustang dyno might be a more correct way to say it because the Dynojet seems to jive pretty well with published stock hp figures. Could be Mustangs read low while Dynojets are about right.

Anyway, Dynojets are by far the most popular of the two and can be found all over. Never heard of a Clayton dyno. I understand the logistical challenge of doing something like this, but, if you are not going to use an instrument that folks know and understand, then you are opening the entire procedure up to ridicule and nitpicking. In the end you might not have buy in from the people that matter, the BMW drivers. But, you might not have buy in from them anyhow.

Anyone wants to do tests in Raleigh I'll buy.

Ron

[dj10]

Well, good points on the different dynos, and we are aware of them, and we would love to run the full set of tests on all of them, LOL. Sadly practicality does enter the equation, but the results will be interpolated, and testing on different types of dynos is part of the plan. And DJ, not just one more test, but many more pulls. We did about 4 or 5 hours on Saturday.
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Jake, I didn't mean you should test on all the different dynos, I brought that up to show everyone that there are differences and no one should be blind to this. Example: if I'm 181 rwhp on a mustang dyno I might be 195 rwhp on a dynojet. The SIR is limiting us to 220 CHP if you calculate this is 180.4 rwhp using the 18% crank to rear wheel loss. So the target number of 220 CHP came from where and which dyno, if any? If the rx7's are using, as another example, a mustang dyno and the SIR is based on a dynojet, we would get killed.
If you won't give us any info about Sat. tests at least give us your personal conclusions and did the SIR's you had even come close to your expectations?? Damn Jake, give us something to think about.
dj

[Joe Harlan]

This is essentially correct. The Dynojet reads higher than the Mustang dyno might be a more correct way to say it because the Dynojet seems to jive pretty well with published stock hp figures. Could be Mustangs read low while Dynojets are about right.

Anyway, Dynojets are by far the most popular of the two and can be found all over. Never heard of a Clayton dyno. I understand the logistical challenge of doing something like this, but, if you are not going to use an instrument that folks know and understand, then you are opening the entire procedure up to ridicule and nitpicking. In the end you might not have buy in from the people that matter, the BMW drivers. But, you might not have buy in from them anyhow.

Anyone wants to do tests in Raleigh I'll buy.

Ron
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If my memory is correct the Dynojet is an inertia type dyno (with optional eddy loadcell) The mustang is a single or double roller type dyno with the eddy loadcell standard. The Clayton is normally a double roller loadable type dyno that works much like a water break engine dyno. All of them are good for reading peak numbers and should be pretty close in those numbers. I would not bother going to a dyno shop that cannot load and hold individual rpm ranges for proper tuning of those rpm and load ranges. Clayton is the old grand daddy of dynos and have always been good units. I would have no problem with results from this type of dyno.

[gpeluso]

Joe,
Glad you think it's a good dyno,but that not what Ron,DJ,and myself are talking about. We are talking about comparing apples to apples. Many HP numbers have been thrown around. AB, talked about an RX7 putting out 182 whp. I'm concerned that the goal itself maybe flawed with 220chp. If that is the goal the BMW would seem heavy. It just seemed like on Friday this information was going to be very open. Time is not on your side. I really seem to like someone like Ron helping out. He seems like a voicce of reason.

Greg

If my memory is correct the Dynojet is an inertia type dyno (with optional eddy loadcell) The mustang is a single or double roller type dyno with the eddy loadcell standard. The Clayton is normally a double roller loadable type dyno that works much like a water break engine dyno. All of them are good for reading peak numbers and should be pretty close in those numbers. I would not bother going to a dyno shop that cannot load and hold individual rpm ranges for proper tuning of those rpm and load ranges. Clayton is the old grand daddy of dynos and have always been good units. I would have no problem with results from this type of dyno.
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[Andy Bettencourt]

I'm concerned that the goal itself maybe flawed with 220chp. If that is the goal the BMW would seem heavy. Greg
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You think so? I think you would be in the minority. Tell us why you think it would be heavy.

http://itforum.improvedtouring.com/forums/...?showtopic=7315

The information WILL be open, once we get it all and make sense of it. Time is of the essence, we undertand that.

AB

[gpeluso]

ab,
minorities can be right,.........I knew you couldn't stay away. Hey, I'm smiling again.

Greg

You think so? I think you would be in the minority.

http://itforum.improvedtouring.com/forums/...?showtopic=7315

The information WILL be open, once we get it all and make sense of it.

AB
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[AntonioGG]

Here's an interesting thread to read about dyno differences:
http://forum.specmiata.com/cgi-bin/ultimat...0786;p=0#000000

As far as the test results...the suspense is killing me! This is worse than watching "24".

Antonio
--no dog in this hunt, but curious about the results

[Joe Harlan]

Joe,
Glad you think it's a good dyno,but that not what Ron,DJ,and myself are talking about. We are talking about comparing apples to apples. Many HP numbers have been thrown around. AB, talked about an RX7 putting out 182 whp. I'm concerned that the goal itself maybe flawed with 220chp. If that is the goal the BMW would seem heavy. It just seemed like on Friday this information was going to be very open. Time is not on your side. I really seem to like someone like Ron helping out. He seems like a voicce of reason.

Greg
[/b]

Greg, I am not going to go into what you like or dislike. I think if you look through several of the threads on this subject you will find an offer of 4 hours of my shop time to help with this problem. I have offered to help install one of these should anyone want to take me up on it.
What I am saying is if all dyno's in question have a properload cell you will get reasonably good data to compare to each other. If the dyno used is nothing but a straight pull inertia dyno you will get big marketing numbers and no other valuble data. WHat would you all do if you went to an inertia dyno and got exactly the number the CRB was shooting for but the car was not drivable on the track? I think these guys are going at it the right way by hold their water until all the data is in. What pisses me off is this is exactly the testing you all were screaming for when the rule was handed down. I would suggest Ron is making a great offer, I would also suggest that if somebody takes him up on it that they bring somebody along that understands what they are looking at. Make sure the Dyno facility has the ability to load at different settings and steady state and that they also have a wideband O2 runnning recording the fuel mixture through the whole process.

[Ron Earp]

I would also suggest that if somebody takes him up on it that they bring somebody along that understands what they are looking at. Make sure the Dyno facility has the ability to load at different settings and steady state and that they also have a wideband O2 runnning recording the fuel mixture through the whole process.
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Joe, I know what I am looking at and have done lots of dyno runs using various equipment including wide band, EGTs, and limited airflow feeds. We can steady state load, static run, and record all sorts of parameters during a run. Depends on which shop. Neither are mine just ones I use because the folks are very good, flexible, and like to fool with cars. I prefer the Dynojet because that is what everyone is used to, most folks, and I find them very repeatable from day to day and very accurate for seeing differences in changes performed. Anyone is welcome to come, someone just needs to produce the car, bring the stuff to tune their BMW, and we'll see what we get.

Ron

[Andy Bettencourt]

ab,
minorities can be right

Greg


[/b]

Anyone can be right, but I am having a hard time understanding why you would think the BMW would be an underdog at the same hp level as the RX-7 given all the other factors listed in the thread. It's easy to just stand up and disagree, but at some point you have to tell us why.

http://itforum.improvedtouring.com/forums/...?showtopic=7315

[gpeluso]

AB,
I have given an example.........since you said you were not going to post until the info comes.....go read........

Greg

Anyone can be right, but I am having a hard time understanding why you would think the BMW would be an underdog at the same hp level as the RX-7 given all the other factors listed in the thread. It's easy to just stand up and disagree, but at some point you have to tell us why.

http://itforum.improvedtouring.com/forums/...?showtopic=7315
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[Andy Bettencourt]

AB,
I have given an example.........since you said you were not going to post until the info comes.....go read........

Greg


[/b]

Never said I wasn't going to post - just not the info until it is ready...and if Jake wanted to post his FIRST hand info, that would be up to him. Try and read the actual words, not what you want them to say.

Link me to your comments. Can't find them.

AB

[MMiskoe]

This might be considered a dumb question but I'll risk that.

If there is so much riding on this testing and so much effort being put into it, why screw around w/ a chassi dyno? Although engine dynos are harder to get set up initially, they have much better ability to provide consistant numbers because of the environmental controls they can provide.

Get the SIR worked out on the engine dyno where its easy to make the changes, then do some pulls on different chassi dynos to show driveline losses & differences between dynos.

You can test forever, but if you don't cmpare apples to apples you are wasting your time.

Tell me where am I wrong in this idea.

Matt

[gpeluso]

AB,
I talked about the end result of HP of the BMW compared to the RX7. Showed the weight differences and brought up the question of what type of dyno used to measure 182whp you claim that an RX7 is capable of. Are you comparing apples to apples. I have a feeling YOU are not. That's right you. You never addressed different readings from dynos,DJ has been asking. Next an CLayton????? Ron makes a great poiunt. Why not use comparable info. The way you are condoning the test info it can interpretted differently. Even, if you hit the goal , how can you give the BMW less power than an RX7 but more weiht?AB, you will not tire me. You are tring to confuse the issue. Just get the info!!!!!!!! You love those little faces, huh.

Greg

Never said I wasn't going to post - just not the info until it is ready...and if Jake wanted to post his FIRST hand info, that would be up to him. Try and read the actual words, not what you want them to say.

Link me to your comments. Can't find them.

AB
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