Dyno results; your opinions wanted

[Jarrett]

This does involve me having a car dynoed, but because my questions are not really of a performance aspect, I decided to post this here.

This was originally posted on Acurazine as the car in question is my 2003 CL-S6.

So, my experience at the dyno yesterday was less than encouraging. I arranged with Redline Performance in Arlington, TX to perform the first of three sets of runs I planned to do. I wanted to one set when I was completely bone stock down to the OEM Acura panel filter, one with the J37A4 intake manifold to finally put that thread to rest and one with the manifold, ported runners, 76mm throttle body and stainless headers. The shop manager knew this going in and told me it would be $50 for each set of pulls.

I showed up yesterday and the shop manager was not there. The other guys were fairly polite and handled the dyno runs for me. It had been raining on my way there, but had stopped for about 30 minutes by the time the car was strapped down (this is relevant in a moment). We performed the first run and got 216.07 hp with no torque reading. There was a wire running back to his computer that was taking an RPM signal from the engine that was broken and twisted together. It came untwisted for the first run and that's the reason I was given for there to not be any torque reading. Fine. We had two more runs so I figured it was not a big deal.

The operator performed the next runs in 3rd gear because he said he was getting up to 130mph in 4th gear and didn't feel comfortable doing that with the tires still being a little wet. He assured me the correction factor would handle it. I understand math and I'm okay with that. I also know that While 4th gear is ideal, 3rd isn't awful from a ratio perspective. The second and third run were done fairly close back to back. The broken wire was twisted back together and we were getting an RPM signal this time. The second and third runs were 16-22whp less than the first run!

I asked why and he said that the decline was due to heat soak. I did drive the car about 45 minutes on the freeway, and another 15 on city streets to get to this place, but that doesn't really add up to me. I'm very non-confrontational, so I didn't press further with the operator. I went inside to pay and ask the guy who was running the shop in the absence of the shop manager and all he did was go get the operator so that I could get the very same explanation. No help there. So, I paid and left. I really want to email the shop manager as I planned on using this place two more times to get all of my upgrades recorded. I just didn't leave there very confident at all.

Can someone else give me an opinion based off of what I've read and let me know whether or not I'm being overly dramatic about this? I don't plan to make trouble with negative reviews or anything, but I still don't feel that I even got the information I went in there for. What good is a baseline if it's not accurate? To be completely honest, I don't think that the 216whp is accurate, but with dynos being so different, only the gains from that point on the same dyno are relevant.

[h22sparkle]

Nice what's the setup and was it tuned and if so by whom

[cb9love]

I would have to talk it over with the shop manager. I don't feel as if the dyno run is even usable with the equipment malfunction. Even if the results are accurate they have been tainted with what could be a precieved malfunction.

[Jarrett]

Nice what's the setup and was it tuned and if so by whom

I'm assuming you didn't read any of the post.

I would have to talk it over with the shop manager. I don't feel as if the dyno run is even usable with the equipment malfunction. Even if the results are accurate they have been tainted with what could be a precieved malfunction.

I did get around to emailing him today. It was pretty awkward, so I was putting it off. I just felt uncomfortable because if I get what I want, I'm still going to have to go back in there with the guys who passed it off as normal before. We'll see what he says.

[owequitit]

This is the stock dyno run on the J32 that came with the car correct?

How many miles does it have on it?

It seems that in good weather (not hot and schweaty as it has been here in Dallas) these engines will do around 220-230WHP bone stock. MAYBE 240, although the output was pretty close to the J30A4, which commonly falls around 230WHP.

So from that perspective, I don't think it is all that far off of the norm.

The torque curve appears to be normal for that generation of Type S J series because it had that little dip in the middle from the runners opening up (as I recall). The 2003-2007 V6 6MT cars basically had the same concept, except that Honda made some refinements to the manifold which sort of eliminated that middle dip. They also didn't have full headers, which may have made a slight difference. I think their ECU's were better too.

It really doesn't seem absurdly off to me, but if you aren't sure, I am sure there is another reputable dyno shop in the DFW area that would be happy to test it. It just will cost you more money.

*EDIT* Is the dyno pull stopping at 5500 related to the wire malfunction?

[Straight Success]

Email and follow-up with a phone call to the manager. If he doesn't rectify the situation, or make up for it when you reschedule another visit, follow up with the BBB, the local media, and social media (which you have already done).

Maybe the manager has good business practices while his employees don't have the same.

All the best.

[Jarrett]

This is the stock dyno run on the J32 that came with the car correct?

Yes.

How many miles does it have on it?

97K miles. I've owned it since 89K miles and the ONLY time I drive it is back and forth from Denton to Bryan nearly every weekend.

So from that perspective, I don't think it is all that far off of the norm.

I was very careful in my email to the manager to not raise any complaints about how much power I made in comparison to something else. While I think it's low, so does everyone else that gets their car dynoed. All dynos read differently and I'm reasonable enough to agree that my best number may be lower than others for that reason. My complaint is how much the second and third runs differ from the first. Your edit may address my speculation here, though.

It really doesn't seem absurdly off to me, but if you aren't sure, I am sure there is another reputable dyno shop in the DFW area that would be happy to test it. It just will cost you more money.

You'd think. I've really been trying to get a company up here in Denton called ATS Racing to do it. They specialize in MR2s. However, they keep blowing me off repeatedly. I eventually settled on this place because they're one of the few places that tune Hondata that aren't backlogged with Gallardos and GT-Rs.

*EDIT* Is the dyno pull stopping at 5500 related to the wire malfunction?

That's something I forgot to type in the forum post but I did address in the email. It never starts dipping, so I don't know why they backed off. Hopefully the manager addresses that in his response.

[owequitit]

I would see what the manager says. It could have just been the operator. Just let him know that you are not satisfied due to the issues with the RPM lead, and results which seem to be low (even though they vary).

Obviously, the lower gear would affect it, but it should have had the opposite effect and driven power up (uncorrected).

Luckily, it is cooling off so if he brings you back in you may get a better result.

Also, my thinking on the correction and the total not being THAT far off was related more to the temps and humidity we have had here lately. I know on my side, the climb performance has been SUCKING BALLS. In fact, just the slight cool off the last few days has made a 10-20% difference in our climb performance (which would be affected similarly to an NA car). That could also explain the relatively low results. They can correct for DA pretty easily, but correcting for humidity and the ECU's response to heat is not as easy.

Hopefully, the manager will get back to you, repair the dyno and give you another run in cooler weather.

*PS - I know what you mean about all the speed shops around here being full with Gallardos and R8's. I have seen more random Lambos driving around the metroplex than any other place on earth. They seem like that are almost as common as Corvettes around here!

[Jarrett]

If there's one thing the Metroplex has in abundance, it's new money.

[Losiracer2]

damn you paid 50 a pull? Try looking on local honda or any import forums in your area for dyno days. I was able to dyno mine for 40 total (3 pulls) and I got a couple brats and hamburgers and soda out of it.

I did 184, 191, 188 whp on 3 back to back pulls torque was 144, 147, 155 all during about a 110 degree day lol

[Mike1357]

The way I understood it was 50 for a "set" (3 pulls).

Although there was a discrepancy with the first pull, the second and third (assuming they were similar to each other) should be valid for your purposes. If what you're trying to accomplish is to measure a power difference between modifications, as long as all subsequent pulls are done in similar conditions and in the same gear, you'll accomplish your goal. It was said before, but dyno readings will vary from machine to machine. I prefer the dyno-jet (in ground, 3000lb roller) because, although the numbers are lower in comparison to, say, a mustang dyno, they are more accurate because they simulate the weight and inertia of the vehicle on the road.

If it really came down to it, try to get a refund for the one invalid pull? Personally, if the first pull had no torque curve, then I feel they should've done a fourth pull. The drop in numbers could be associated with heat if the fan they had in front of your car wasn't directed to the radiator well enough to cool it efficiently.

[Raf99]

The way I understood it was 50 for a "set" (3 pulls).

Although there was a discrepancy with the first pull, the second and third (assuming they were similar to each other) should be valid for your purposes. If what you're trying to accomplish is to measure a power difference between modifications, as long as all subsequent pulls are done in similar conditions and in the same gear, you'll accomplish your goal. It was said before, but dyno readings will vary from machine to machine. I prefer the dyno-jet (in ground, 3000lb roller) because, although the numbers are lower in comparison to, say, a mustang dyno, they are more accurate because they simulate the weight and inertia of the vehicle on the road.

If it really came down to it, try to get a refund for the one invalid pull? Personally, if the first pull had no torque curve, then I feel they should've done a fourth pull. The drop in numbers could be associated with heat if the fan they had in front of your car wasn't directed to the radiator well enough to cool it efficiently.

^^ This. And your numbers are accurate. The place I go to uses a mustang dyno and the numbers are close. Heat soak doesn't help but is expected.
I wouldn't complain over one loose wire. Even with a proper wire it sometimes needs adjusting to get a reading depending what your source is.

I know sometimes the shop I use has far better cars than mine (porches, vett, skylines, etc.) and the owner delegates my pulls to other employees. Sure it feels like I'm worthless, but I understand.

I would simply ask next time you pull to have the owner there.

[h22sparkle]

This setup is fairly small. Im not sure what kind of numbers your car puts out stockwise: shrugs: I know I made more power than that stockwise with my si with just a tune and when I modded it and that dip in the curve is definitely holding you back did you even bothered getting it tuned.?

[deevergote]

Due to the missing RPM lead on the first pull, which was operator error, you should at least have been given a 4th pull to compensate.

The CL-S is rated at 260hp, so with a full 20% drivetrain loss, you're looking at 208whp. 221whp with a 15% loss. I'd say that puts your initial pull right smack in the reasonable middle of that estimate.
Given the age of the engine, the 3rd gear pull (as Scott said, it should be higher... but perhaps there was some overcompensation in the correction?), atmospheric conditions, and dyno calibration, a lower reading wouldn't be unreasonable. Heat soak is definitely a possibility as well, considering a 45 minute highway drive. Did the engine have a chance to cool down once you arrived, or did you pull it right onto the dyno?
Had the first pull not shown so high a reading, I'd be tempted to say the lower ones are to be expected given the factors mentioned above. The fact that the first run was 7-10% higher than the next two seems a bit fishy.

Hopefully the manager works with you. As I said, the disconnected lead for the first pull makes that pull essentially worthless. Especially since that pull reads significantly higher than the other two (would connecting that lead have anything to do with that?)
"Whoops! We messed up! You're only going to get 66% of what you paid for today. That's cool, right?" That doesn't fly in my book.

[Jarrett]

The way I understood it was 50 for a "set" (3 pulls).

This is correct.

Although there was a discrepancy with the first pull, the second and third (assuming they were similar to each other) should be valid for your purposes. If what you're trying to accomplish is to measure a power difference between modifications, as long as all subsequent pulls are done in similar conditions and in the same gear, you'll accomplish your goal. It was said before, but dyno readings will vary from machine to machine. I prefer the dyno-jet (in ground, 3000lb roller) because, although the numbers are lower in comparison to, say, a mustang dyno, they are more accurate because they simulate the weight and inertia of the vehicle on the road.

I still don't understand how those numbers are valid. If I'm wanting to measure the gains from installing a J37A4 manifold (estimated +12-15whp), how can I determine those numbers when the baseline I'm basing those gains off of fluctuate 22whp? I've never had another dyno fluctuate by more than 5whp. And that was a Camaro SS with a lot more power (292.4 to 297.6whp), so proportionately, it didn't vary much.

If it really came down to it, try to get a refund for the one invalid pull? Personally, if the first pull had no torque curve, then I feel they should've done a fourth pull. The drop in numbers could be associated with heat if the fan they had in front of your car wasn't directed to the radiator well enough to cool it efficiently.

Personally, I'd like all three redone. Just get three back to back to back runs in, and call it a day. That way weather conditions are all the same and I have the same information that everyone else that pays for runs gets. The cooling was sufficient. They had one of those large rolling fans directly in front of the car with the hood popped. Then they one of those blowers inches from the radiator.

This setup is fairly small. Im not sure what kind of numbers your car puts out stockwise: shrugs: I know I made more power than that stockwise with my si with just a tune and when I modded it and that dip in the curve is definitely holding you back did you even bothered getting it tuned.?

You continue to display an inability to read. The "setup" is a completely factory car. It happens to not be an Accord. And no, I didn't bother getting my completely stock OBD2b car tuned.