Low Dyno Numbers - Need some opinions

[delita1]

Car stock made less than impressive numbers, I was wondering why that could be - figured, do upgrades and see if they're made up for. Low and behold, they weren't.

Stock baseline 360/365 horsepower, post JB4+downpipe/exhaust, only made 390's whereas I've seen other (Z4 M40i btw) make 380s-390s stock, and more like 430's DP/JB4. In fact, per the JB4 forum one of the guys there made 433 on map2 with 91 octane, I'm not even breaking 400 with 93 octane and EWG installed. Made 30 horsepower/70 torque, but the horsepower numbers are very low. All things considered, what are the biggest contributing factors out there to look for in figuring out what is causing those drops?

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[Raidernation]

What type of dyno does your tuner use? What elevation are you at. There so many factors in dyno numbers. I am sure someone with more knowledge will chime in. I wouldn't worry about "The HP Numbers" and enjoy the car.

 

[GreyMadder]

Car stock made less than impressive numbers, I was wondering why that could be - figured, do upgrades and see if they're made up for. Low and behold, they weren't.

Stock baseline 360/365 horsepower, post JB4+downpipe/exhaust, only made 390's whereas I've seen other (Z4 M40i btw) make 380s-390s stock, and more like 430's DP/JB4. In fact, per the JB4 forum one of the guys there made 433 on map2 with 91 octane, I'm not even breaking 400 with 93 octane and EWG installed. Made 30 horsepower/70 torque, but the horsepower numbers are very low. All things considered, what are the biggest contributing factors out there to look for in figuring out what is causing those drops?

Where in VA are you? What shop?

 

[Benjilis]

I’m on a JB4 and run map 3 with e30
I hit a peak of 444 whp on a a dyno.
car is completely stock

I would suggest sending your logs to BMS via email at map 1 and increase to map 2+ once you get the “ok” from the BMS team.

 

[VA90]

Normally, I would say never try to compare one dyno to another but the delta (which is where you should focus) is less than I would expect. What map are you on? 1? Either way, definitely send the logs to Burger like Benjilis says. You should also go over to n54tech.com for more help.

 

[delita1]

Where in VA are you? What shop?

Richmond. National Speed.

I'm going to run logs over the next few days - the dyno on Map 3 looked nuts, but I also think the tech who ran the map (with his JB4) probably didn't have the right firmware - I updated it when I got the car back to V18 beta.

That being said, I thought the initial numbers were disappointing in comparison to other baselines as well as the post JB4 dyno. The car has ~1000 miles so it's not fully "broken in" per say - not sure if that would have any cause for the numbers not being quite where they should yet or not.

I will also run the tank dry and try a better 93 octane (I had just filled it up at a local Kroger with 93) - the BMS Z4 that they posted dynos for last year was running 399 horsepower and 409 torque on 91, whereas I came back with like 361 horsepower / 380 torque on my baseline. His post JB4 numbers on map2 91 oct were also 30 hp / 40 torque higher than my map3 on 93. I also have the EWG installed.

 

[dethred]

I live 45m from you. We can meet up and compare how the cars feel if you want. I'm a 21 with JB4, catless dp, and exhaust.

 

[Xxyion]

you're using the dyno wrong. A dyno is a tool meant to gauge your improvement based on the mods that you added and not to compare your stock numbers vs someone else's. Thats why every dyno will read differently and on different days at different elevations. You could dyno where you are and make 360whp and then come to California and make 390 whp on the same dyno type.

making 390 after JB4 vs your base 360 means you made 30 whp over stock. Thats the number you need to focus on.

 

[dethred]

you're using the dyno wrong. A dyno is a tool meant to gauge your improvement based on the mods that you added and not to compare your stock numbers vs someone else's. Thats why every dyno will read differently and on different days at different elevations. You could dyno where you are and make 360whp and then come to California and make 390 whp on the same dyno type.

making 390 after JB4 vs your base 360 means you made 30 whp over stock. Thats the number you need to focus on.

He did make a post addressing virtually everything you just said. He's comparing against a Z4 on the same dyno, and he also feels that 30hp isn't enough of a delta... I'd have the same concerns.

 

[delita1]

I live 45m from you. We can meet up and compare how the cars feel if you want. I'm a 21 with JB4, catless dp, and exhaust.

yeah this would be great man, especially if you know some good spots to do some testing. It’s going back to the shop tomorrow for a week to do XPEL then I’ll be good to go

 

[dethred]

yeah this would be great man, especially if you know some good spots to do some testing. It’s going back to the shop tomorrow for a week to do XPEL then I’ll be good to go

Sounds good, PM me when you're ready. Also, if you're willing to spend the $150, get a dragy. Performance numbers don't lie, even if it seems like your car is making less power.

 

[delita1]

Sounds good, PM me when you're ready. Also, if you're willing to spend the $150, get a dragy. Performance numbers don't lie, even if it seems like your car is making less power.

Draggy will be here tomorrow actually

 

[Xxyion]

He did make a post addressing virtually everything you just said. He's comparing against a Z4 on the same dyno, and he also feels that 30hp isn't enough of a delta... I'd have the same concerns.

However he also admitted that the run was also based on a run that was made last year. As i stated before, the same dyno can and will read differently even based on the day. What if it was colder that day and the Z4 was able to make and hold more boost compared to when he did a dyno run where it was hot and his car was heat soaking. Hell even a bad batch of gas will cause different numbers.

I mean who knows...maybe he's right.

 

[dethred]

However he also admitted that the run was also based on a run that was made last year. As i stated before, the same dyno can and will read differently even based on the day. What if it was colder that day and the Z4 was able to make and hold more boost compared to when he did a dyno run where it was hot and his car was heat soaking. Hell even a bad batch of gas will cause different numbers.

I mean who knows...maybe he's right.

I'm no expert but that's quite a difference based on the day. It has been in the mid 50's in Richmond the past week or two, at the most. Temperature probably wasn't a factor. I live 40 miles away, and my IATs haven't gone above 80 -when driving- since I got the car last November. My guess is the shop he used probably also agrees that something is possibly wrong, otherwise he probably wouldn't have been concerned. We will see his dragy numbers and I'll probably do a few test runs with him and that will be fairly definitive.

 

[delita1]

I'm no expert but that's quite a difference based on the day. It has been in the mid 50's in Richmond the past week or two, at the most. Temperature probably wasn't a factor. I live 40 miles away, and my IATs haven't gone above 80 -when driving- since I got the car last November. My guess is the shop he used probably also agrees that something is possibly wrong, otherwise he probably wouldn't have been concerned. We will see his dragy numbers and I'll probably do a few test runs with him and that will be fairly definitive.

Appreciate it - and yes the shop said it looked off too, unfortunately they were pretty full at the time and I had to get it out of there and over to my PPF installer this week. I'll be back in the shop by next week looking into it and running some more tests on different JB4 maps as well as having them check for anything that could cause a drop in horsepower.

The only other piece of information I can offer is that the car only had 850 miles on it when running these dynos, not fully past the break in period and I have personally never had a car on a dyno brand new so I can't even speak to how much numbers can fluctuate once the car is "broken in".

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