: Dyno'd today; 40HP lower than average



M5eater
07-09-11, 07:56 PM
Went to my local dyno today; the results were not special and a little concerning.

Bear in mind, my 100% stock G8 GT with a 6L80E put down 311/333 on this dyno, which equated to < 15% loss.

my results;
422.63/420 @ 90F/ 23% humidity on SAE correction.


Checked the air filter and intercooler hoses for kinks, but didn't see any. Using Gary's data here
http://www.cadillacforums.com/forums/cadillac-cts-v-series-forum-2009/228746-im-still-collecting-factory-stock-dyno-2.html

this is the lowest dyno for a V2 by a slim margin, although my first run was acutally 419, second and third runs were consistiant within 4hp/4tq.


I'm trying to think of possible reasons for a percieved 24% drivetrain loss and only 14-15% loss on a simiar drivetrain.
so far all I have is;

it was 90F today.. but uncorrected only added another 3hp or so.

The car vibrates above 70MPH, and I've had to add some coolant(<1/2 a quart probally) to the intercooler a few times, but other than that, I kept to the breakin period sans 2-3 times while being naughtly (and one of those after I had the oil changed) this was on 700mile mobil 1 and the car had been sitting for ~ 45min to an hour before the run. Trans temps were ~ 165 during the run, in 4th gear sport mode and TC off.

I understand that Gary's data is pretty broad with consistiant down-ward numbers into the 420s, but can anyone think of what might be happening here? I'd like to check the plugs, but I doubt they're that bad out of gap to make up another 20hp or more. I haven't had an opportunity to check, but it appears to be boosting correctly in the 8-10psi range. This was also at all aspects in chesapeake VA, which is more-or-less sea-level.

http://i813.photobucket.com/albums/zz56/blmlozz/photo2Large.jpg

Gracias.

Domsz06
07-09-11, 08:18 PM
These cars are dyno queens. It was also hot so you prob had heat soak.

How many miles are on her?

Did you just run one run?

M5eater
07-09-11, 09:49 PM
These cars are dyno queens. It was also hot so you prob had heat soak.

How many miles are on her?

Did you just run one run?

just over 2,000 miles
best of 3 runs.

I had in the back of my mind it was IAT's as well, and since the cooler is jamed back in there we could not spray. I also didn't have a way to monitor IAT's either, but the fact that it remained so consistiant threw me into thinking it was something else?

PhxTriode
07-09-11, 11:50 PM
Remember correction is for NA motors. Boost compounds the effect especially with crank dependent boost at that.

I see upto 50hp variance from winter to summer

Domsz06
07-10-11, 12:08 AM
+11111 esp for us folks in the "hot as hell" spots of the world.

baabootoo
07-10-11, 12:17 AM
Unless it was sitting in the shade for an hour, with the hood up, it will be that low. On a Dynojet, I saw a 40 HP difference, with just a 20-minute cool down from VERY hot.

M5eater
07-10-11, 09:10 AM
Thanks for the responses, I've had F/I cars before, but never experienced heatsoak this baddly before, maybe I should look at what temps my previous runs were done at. After looking @ the G8's dyno, I had forgotten it was a cool 65F that day.

Razorecko
07-10-11, 09:20 AM
Looks about right to me, any mods or pure stock ? Heat is a killer for our cars, hence my constant push for a good aftermarket hood =)

M5eater
07-10-11, 09:25 AM
Looks about right to me, any mods or pure stock ? Heat is a killer for our cars, hence my constant push for a good aftermarket hood =)

100% stock. My previous F/I cars had at least 1 good run before they fell off a clif. the Consistancy is what threw me off. Give's me a reason to go back in november I suppose. :)

PremierJosh
07-10-11, 04:25 PM
How long did the car sit with the hood up or with the dyno fan running before the first pulls. Without logging iat's at least it's just a guess. I just dynoed a brand new one that was exactly where you are.

cbloveday
07-10-11, 09:00 PM
JOSH, please clear your inbox.

dvandentop
07-10-11, 11:50 PM
it is rediculously hot here not surprised on the low numbers

zinner
07-11-11, 12:05 AM
Might be some encouragement to get some new business for the dyno shop.

M5eater
07-11-11, 09:32 PM
Might be some encouragement to get some new business for the dyno shop.
I've been going to this place for years, I would find that unlikely.


How long did the car sit with the hood up or with the dyno fan running before the first pulls. Without logging iat's at least it's just a guess. I just dynoed a brand new one that was exactly where you are.
hood up? Maybe 10minuites,

The car sat closed for at *least* 45minuites. I was the last of a medium sized group to run.




it is rediculously hot here not surprised on the low numbers
it is, and yet, it was super consistiant. The guy didn't let it sit, we had a large CFM fan running in front of course, we got it on there, and did our runs.

The car certinally ''felt'' fast comming back from NJ today doing some WOT @ highway speeds. When she goes in for the problems she has I might ask my dealer what their thoughts are. One of my friends keeps bugging me about telling them as his friend with a GT500 managed to get his dealer to acutally go diagnose it on the dyno and it ended up being a throttle blade issue. So if anything it'll be to shut him up ;)

JOEYCTS-V
07-11-11, 09:44 PM
Where in Jersey did you have it dynoed?

M5eater
07-11-11, 09:52 PM
Where in Jersey did you have it dynoed?

No where, this was done in Chesapeake. I drove to new brunswick NJ this weekend and back for family.

DoingOK
07-11-11, 10:02 PM
So you must be the gentleman I was told about. I know the shop (and owner) where you got the car dynoed.....I was @ the Performance Autosports open house when someone got the text and told me about your dyno. I was going to dyno myself, but there was too many in line.

Gary Wells
07-11-11, 10:04 PM
M5eater:
The most common thing that I can think of would be the heat.
Did they use large enough fans to cool the motor down between runs?
Also, a lot of dyno shops run those fans on the motor when the dyno run is being performed.
Could it be their dyno?
Or could you get there early enough to let the car cool down before the dyno run?
Just some random thoughts.

M5eater
07-11-11, 10:22 PM
So you must be the gentleman I was told about. I know the shop (and owner) where you got the car dynoed.....I was @ the Performance Autosports open house when someone got the text and told me about your dyno. I was going to dyno myself, but there was too many in line.

LOL, there were probally a dozen people waiting for me to run (this was a bunch of MS3/MS6/MSP guys) but I didn't know I made the gossip level of underwhelming-ness.

are you sure?

Allaspectsmotorsports specifically is where we were @, Guy's name is keenan.


Did they use large enough fans to cool the motor down between runs?
unlikely. This is a fairly hole in the wall shop. 1 industrial floor fan is all you get,a few minuites between runs if you're lucky.


Could it be their dyno?

maybe, but unlikely, as I said before, the G8 GT with the 6L80E hit a spot-on 310.7/333 which is ~ 14.5% drivetrain loss. The CTS was probally past what the Quattro A4 S4 I had previously were.


Also, a lot of dyno shops run those fans on the motor when the dyno run is being performed.

you get the 1 fan, and you used to get none..


I may just wait until the winter to run again under similar conditions to the G8, and find a way to spray the exchanger(it's the one in between the radiator and condesor right?), and if I still post some low numbers *then* decide to do something.

I probally just need to find a better shop, but it's fairly barren in the Hampton Roads area.

DoingOK
07-11-11, 10:49 PM
I know Keenan and Chelsea........I was in Richmond @ Performance Autosports while you were getting dynoed. I was sitting there when a friend got texted as to your results. I said it sounded a little low, but every dyno is different and it was hot outside. I'd like to see the black paint sometime. I live in Smithfield.

Rich

M5eater
07-11-11, 11:52 PM
I know Keenan and Chelsea........I was in Richmond @ Performance Autosports while you were getting dynoed. I was sitting there when a friend got texted as to your results. I said it sounded a little low, but every dyno is different and it was hot outside. I'd like to see the black paint sometime. I live in Smithfield.

Rich

Keenan is a good guy, I just wish he'd make it big and get the shop updated a bit. Bungie cord fan on a stick as a dyno fan has a certain dirty feel LOL.


Ask him who requested he change shirts before he sat in the suede seats in the V (to which he corrected; alcantara) and my name will come up

If you go to the lions club meet every 1st and 3rd friday @ the race-car place (can't remember the name now) I'll likely show up. I'm out in Suffolk, so we're not too far away.

jb7952
07-12-11, 10:41 AM
Does heat affect a SC motor more than a NA motor? The reason I ask is that it's been very hot here lately (90+, humid) and the car seems quite a bit slower. Maybe it's just in my head, or I'm getting used to it?

SPEED74V
07-12-11, 11:09 AM
Does heat affect a SC motor more than a NA motor? The reason I ask is that it's been very hot here lately (90+, humid) and the car seems quite a bit slower. Maybe it's just in my head, or I'm getting used to it?

You will be able to tell the difference big time, especially at 90+ degrees & humid. I live in South Dakota and some days it is hot and humid then the next it is 65 degrees and these supercharged cars definitely like cooler air.

dvandentop
07-12-11, 11:15 AM
You will be able to tell the difference big time, especially at 90+ degrees & humid. I live in South Dakota and some days it is hot and humid then the next it is 65 degrees and these supercharged cars definitely like cooler air. where do you live in south dakota? I am in sioux falls i have a silver sedan.

Razorecko
07-12-11, 12:24 PM
the motor can handle the heat better than the humidity. So if its 65 but 100% humidity you will feel it where as if its 80 and 10% humidity it will still feel good.

Luna.
07-12-11, 04:56 PM
Did you get the chance to inquire about your IAT2s?

M5eater
07-12-11, 05:03 PM
Did you get the chance to inquire about your IAT2s?
I didn't know how to log or view them, so we did not take measurements. She goes in this thursday for other stuff, I plan to ask them(the dealer) about it, I don't expect they'll make a big deal out of it, in which case I'll go back with some ice and spray an see if I can duplicate or improve the numbers. If I can't improve, I'll have more ammo. If they do improve by a good amount, we'll know what went wrong.

serturbo
07-12-11, 06:44 PM
IAT2s kill my ET on the strip. 80-90 IAT2 = 12.0-12.1; 90-100 = 12.1-12.2; 100-110 = 12.2-12.35.

Luna.
07-12-11, 06:47 PM
I didn't know how to log or view them, so we did not take measurements. She goes in this thursday for other stuff, I plan to ask them(the dealer) about it, I don't expect they'll make a big deal out of it, in which case I'll go back with some ice and spray an see if I can duplicate or improve the numbers. If I can't improve, I'll have more ammo. If they do improve by a good amount, we'll know what went wrong.

That's cool.

I agree with most others in this thread that the heat and humidity have the potential to torture your numbers, almost not withstanding the SAE correction factors. I know that, in theory, they are supposed to adjust the rwhp to a "standard," but I swear, my rwhp numbers are almost always higher if my car is tested on a cooler/less humid day than the opposite, yes, even considering the SAE adjustment. This is strictly anecdotal and isn't intended to be considered as proof of anything, but it just strikes me that both my Vs (well, when my 1st gen was maggied) will/would, SAE corrected, generate higher numbers in certain atmospheric conditions.

As far as the IAT2s, that's a fairly easy number to look up when the car is on the dyno. I almost always ask the dyno operator to let me know what IAT2s the car is generating on the dyno. If that number starts to get too high, I'm going to start asking questions and that could be a reason why a car isn't making as much power as one might otherwise expect.

I'm sure some of the dyno operators/experts can chime in here for a detailed explanation if I'm missing something

SPEED74V
07-12-11, 07:44 PM
where do you live in south dakota? I am in sioux falls i have a silver sedan.

That's pretty sweet - I live in Sioux Falls also and mine is a silver sedan:D

We will have to get together sometime. I really want to make it out to the road track by omaha a couple times yet this summer. I just ordered some TSW Wheels and NT01 tires for the track yesterday. My car will be going to Speed Techniques by Tea this fall for some E85 and other upgrades.

Sorry - don't mean to be a thread jacker