ESS 550 Low Dyno Results?

[Iyzmi]

I've had my ESS 550 kit installed for a few months and about 4k miles now so I decided to run it on the dyno and see what kind of numbers I'd make. My car is stock other than the supercharger and ACM exhaust mod. I was expecting to put down somewhere around 470hp (on 93oct) but came a little over 20hp short at 448.

At first I thought I might have a boost leak coming from the intake boots, they looked a little deformed when I installed the intake manifold and I was never quite satisfied with how the manifold seated. I replaced those and went back to the dyno, only to make pretty much the same numbers. I'm wondering if 448hp/300tq is within the realm of "normal" or if there is an issue I should be hunting for?

[///M Kidding]

I'm no expert but I'd be mad if I bought a SC kit and only gained 30 some HP:

[Iyzmi]

Originally Posted by ///M Kidding

I'm no expert but I'd be mad if I bought a SC kit and only gained 30 some HP:

So would I, luckily that's not the case. A stock M3 dynos around 340-350.

[Iyzmi]

Here's a picture of how the manifold is seated with the new intake boots. Does this look right? It seems to me like it should still be lower in the boots but it won't go any lower and is "bottomed out" in this position.

[Hierlevelz]

Originally Posted by Iyzmi

Here's a picture of how the manifold is seated with the new intake boots. Does this look right? It seems to me like it should still be lower in the boots but it won't go any lower and is "bottomed out" in this position.

Looks normal.

[Iyzmi]

Originally Posted by Hierlevelz

Looks normal.

Thanks for the input. I'm wondering because all the pictures I've seen show the lip of the velocity stack sitting flush against the top of the intake boot.

[Rat3d ///M]

Velocity stacks look normal, but your numbers do not. FWIW, I dynoed 559bhp and 371lb/ft @ around 7600rpms (hp would've been higher if he took it to redline but he backed off about 800rpms early). That was with resonated test pipes (primary cat delete) acm exhaust mod and an ESS tune

Of course this was read in bhp, as the dyno I used just reads that way (not sure how that works, but that's just what the guy said) but factoring in even 18% drivetrain loss which I think is high I am at 449whp and 305 lb ft which is closer to where your numbers lie.

Of course I should be closer to 585bhp with my test pipes at redline, which puts my numbers higher than yours (which is understandable as you have primary cats). I don't know what to tell you, your numbers don't seem too terribly low, but I would've expected higher (i've heard 470rwhp is normal for the 550 kit).

[///M Kidding]

Originally Posted by Iyzmi

So would I, luckily that's not the case. A stock M3 dynos around 340-350.

Oh I thought your numbers are bhp not whp

[pbonsalb]

448 rwhp seems in the ballpark though perhaps on the lower end of the range for a non intercooled ESS VT 550 kit on an otherwise stock car. Your muffler baffle deletion adds no power. A full X pipe or test pipes would add power. The kit is rated at 550 crank. Driveline loss is around 15%. 85% of 550 is 467 rwhp. You are a little low.

I would want to know what your IAT were on the dyno. Since you are non intercooled, they could have been high, and that saps power. The dyno correction factor compensates for weather conditions, not heatsoak or pulled timing. Insufficient cooling fans on motor while running on the dyno (there is no airflow on a dyno unlike driving at speed, so fans are needed) could lower the results. And a need for maintenance such as an old air filter or worn spark plugs or weak coils could reduce output. The top end of your graph looks a little choppy for smoothing set at 5, for example, which might indicate an issue.

[///Mobbin]

I'm considering an ESS 550 kit now so curious how this plays out.

Best of luck with a resolution OP, lot's of good advice here already!

[Iyzmi]

Originally Posted by pbonsalb

448 rwhp seems in the ballpark though perhaps on the lower end of the range for a non intercooled ESS VT 550 kit on an otherwise stock car. Your muffler baffle deletion adds no power. A full X pipe or test pipes would add power. The kit is rated at 550 crank. Driveline loss is around 15%. 85% of 550 is 467 rwhp. You are a little low.

I would want to know what your IAT were on the dyno. Since you are non intercooled, they could have been high, and that saps power. The dyno correction factor compensates for weather conditions, not heatsoak or pulled timing. Insufficient cooling fans on motor while running on the dyno (there is no airflow on a dyno unlike driving at speed, so fans are needed) could lower the results. And a need for maintenance such as an old air filter or worn spark plugs or weak coils could reduce output. The top end of your graph looks a little choppy for smoothing set at 5, for example, which might indicate an issue.

Yup, I'm aware that the exhaust mod adds no power. Don't know what the IATs were but the ambient temp was around 60F. Keep in mind the runs were weeks apart too. The car was not heat soaked for any of the runs as far as I could tell. I could put my hand on the manifold and head unit and they were not excessively hot. Oil temp was at about 200. Air filter and spark plugs are brand new, installed alongside the rest of the kit ~4k mi ago. The dyno tech actually mentioned that it was the straightest and smoothest graph he had ever seen .

[kerrit]

when was the last time you replaced your primary 02 sensors? They are wideband sensors and have a direct impact on engine performance. Mine were starting to read off a bit at 40k miles, even though they threw no codes

[pbonsalb]

If he logged AFR on the dyno, rich readings that cost power would show up, or lean readings that cause detonation. Its useful to use the tailpipe sniffer option as well as the boost log option.

[617E90M3]

You need test pipes. Will net you the 20 you are missing. I have a 550 kit and put down 470whp on a terrible day ( 88F / 65 humidity )

The VT1 kits really pick up a difference with good/bad weather. I would pick up some test pipes as that's the best next mod for your car.

A better test of "power" IMO is trap speed @ the track. Do a soft launch and see what you are trapping.. as EVERY dyno reads differently.

[Iyzmi]

Originally Posted by kerrit

when was the last time you replaced your primary 02 sensors? They are wideband sensors and have a direct impact on engine performance. Mine were starting to read off a bit at 40k miles, even though they threw no codes

I don't believe they have been replaced. How can I test if they are reading correctly or otherwise how did you know when to replace them?

Originally Posted by 617E90M3

You need test pipes. Will net you the 20 you are missing. I have a 550 kit and put down 470whp on a terrible day ( 88F / 65 humidity )

The VT1 kits really pick up a difference with good/bad weather. I would pick up some test pipes as that's the best next mod for your car.

A better test of "power" IMO is trap speed @ the track. Do a soft launch and see what you are trapping.. as EVERY dyno reads differently.

You put down 470 with test pipes? That would make me feel a little better about my numbers on stock cats, I thought people were making nearly 500 with test pipes. The weather should have been working in my favor though as both runs were at about 55-60F. I'm reluctant to do test pipes for a few reasons. Mainly, I need to be able to pass emissions and don't want the car to be any louder as my neighbors probably already hate me with 5:30am cold starts as it is.

[6ixSpd]

The key point here is the lack of a before boosted dyno... you can't take dyno numbers as absolutes without stock to compare the gains with.

[JEllis]

Originally Posted by Iyzmi

Here's a picture of how the manifold is seated with the new intake boots. Does this look right? It seems to me like it should still be lower in the boots but it won't go any lower and is "bottomed out" in this position.

The bottom of the stacks were a little more flush with the rubber when I installed my kit. You really have to make sure the manifold is all the way down. That being said, ESS has refined their velocity stack design over the years and this could be the new norm.

I would say your numbers are in the ballpark for a car with a full set of cats. A lot of the near 500 WHP ESS 550 dynos you see are from cars that had either the primaries or both sets of cats removed prior to, or inclusive with the SC install.

[Iyzmi]

Originally Posted by JEllis

I would say your numbers are in the ballpark for a car with a full set of cats. A lot of the near 500 WHP ESS 550 dynos you see are from cars that had either the primaries or both sets of cats removed prior to, or inclusive with the SC install.

Right. I am under the impression that 470 was expected with full cats and 500 with test pipes or an x pipe. Even people with 535 kits and stock cats seem to dyno more than 448 though, hence my mild concern. I wouldn't expect test pipes to add more than ~25hp.

[JEllis]

Originally Posted by Iyzmi

Right. I am under the impression that 470 was expected with full cats and 500 with test pipes or an x pipe. Even people with 535 kits and stock cats seem to dyno more than 448 though, hence my mild concern. I wouldn't expect test pipes to add more than ~25hp.

I would say 470 is the lower end of a 550 kit with cat delete with 500 being the high end. Towards the end of the ESS 535 run, the kits were supplied with the 550 pulley. I had a 535 kit on my car and when the 550 kit came out I asked ESS and they said to measure my pulley it was the updated 550 pulley. So, even some of the 535 dynos you are seeing are really late version 535 kits.

Your within 22hp of your "goal". I would almost say its just a low reading dyno but it could be something as simple as bad plugs, a tiny boost leak, crappy fuel. What was your stock dyno, if you did one?

[Iyzmi]

Originally Posted by JEllis

I would say 470 is the lower end of a 550 kit with cat delete with 500 being the high end. Towards the end of the ESS 535 run, the kits were supplied with the 550 pulley. I had a 535 kit on my car and when the 550 kit came out I asked ESS and they said to measure my pulley it was the updated 550 pulley. So, even some of the 535 dynos you are seeing are really late version 535 kits.

Your within 22hp of your "goal". I would almost say its just a low reading dyno but it could be something as simple as bad plugs, a tiny boost leak, crappy fuel. What was your stock dyno, if you did one?

Unfortunately I do not have stock dyno numbers to compare with. I would think comparing Dynojet numbers to other Dynojet numbers would be close-ish, but obviously not perfect. If anything, I was thinking I'd read a little higher than average due to using 93 oct fuel over 91, and the colder ambient temps/low humidity here in WI. FWIW, the tech mentioned their dyno is not known for reading low and always nets comparable results to other Dynojet results he's seen.

Plugs are only 4k miles old and fuel was different between the two sessions since they were weeks apart (I only use Shell, Mobil, or BP). I thought it might be a tiny boost leak from the intake boots but those are brand new now too. Not sure where else to look for a boost leak, especially one that would only be ~.5-1 psi.

The car runs great and builds power very smoothly. I'm very satisfied with the performance overall, the dyno numbers just lead me to believe something is not 100% right. I don't plan on perusing this "issue" too much further if it's not something obvious at this point. Just a little disappointed that I somehow ended up with the lowest reading 550 kit I've ever seen posted.

[dragonsi]

How many miles are on the car? Maybe check to see if you might have a weak coil pack

[Iyzmi]

Originally Posted by dragonsi

How many miles are on the car? Maybe check to see if you might have a weak coil pack

49,500. How would I check that?