aidandj

iTrader: (5)

Ahhh. The good old FM dyno. That explains it.

concealer404

iTrader: (3)

It didn't, though. Unless you're looking at a different chart.

The chart in OP shows more power at 3800 than your car made at 4000rpm. Almost exactly 30wtq more, ASSuming that the dynos read equally, which they almost assuredly don't.

You have a 3500rpm window of 200wtq or above. OP has a 4500rpm or greater window of 200wtq or above.

Your car looks healthy though. Got a chart from a dyno that is more common in order to compare apples to apples?

Goodwood

No, that's why I was asking. I mentioned dynos all being different earlier. Car feels awesome.

aidandj

iTrader: (5)

Sure. But you ignored the fact where you were wrong

Savington

iTrader: (31)

No apology, no retraction? Lots of negcats for you sir. You don't make more power at 4000rpm. You make a lot less, in fact. You also neglected to mention that your "15psi" was actually 17psi, since FM is at 4700ft of elevation. You should be very wary of sharing that dyno chart on this forum, since FM's dyno is notorious for reading extremely high. The OP's dyno chart is from a Mustang which reads ~10% below a Dynojet.

So yes, the OP's results are very impressive, and you owe him (and us) an apology.

If you think your 3071 "feels awesome" an EFR6758 would rock your world.

Colipto

Fun read, would read again LOL

codrus

As a concrete example comparing FM's dyno to a sea level dynojet (which is sort of the gold standard for comparable dynos), my car made 324hp/293tq at FM, 290hp/270tq on the dynojet. Those were both at 215 kpa MAP (roughly 16.5 psi boost at sea level, closer to 19 at FM), and with all the same hardware config.

Turbo cars in Grand Junction are always going to be much peakier than they are sea level, because the lower barometric pressure means more time to spool up and higher WG duty cycles, so lower VE once the turbo IS spooled.

My car later made 340/325 on that sea level dynojet running a higher MAP. I couldn't run it at that level at FM because the turbo was running out of steam, so there's no direct comparison there.

--Ian

Lexzar

iTrader: (2)

So what you're saying is if I use a Hydra in my car I make 10% more power.

emilio700

iTrader: (3)

FM will readily admit that their Rototest does not match seal level corrected Dynojet whp numbers. That said, FM's dyno does appear to be pretty consistent to itself over the years. As such it is a good tuning tool, just hard to compare net numbers from other dynos. FM knows how to tune a car so it's still a great option if it works out for you logistically, or you need an ego boost

concealer404

iTrader: (3)

That dyno wasn't on a Rototest if it was done anytime in the last couple years. I don't find the numbers coming out of their current dyno any more believable, but it's a tuning tool so it doesn't matter much.

Would make threads like this a lot less confusing if they would use a "normal" dyno, though.

codrus

FM's Rototest crapped out a while ago, and apparently the vendor didn't make replacement parts for it any more so it became junk. They have a different one now -- I think it's a Dynocom.

And no, even with a more common dyno, it would be essentially impossible to compare FM's numbers to sea level ones. With positive displacement pumps (like NA engines or roots blower) you can apply a linear correction factor and get something that's approximately right, but turbos are more complex. They operate on pressure differentials and when you lower the ambient pressure you drastically change their parameters, it's like you're using a totally different turbo.

Before the Rototest they had a DynoJet 248 (basically the most common dyno around). I ran my car there back in the early 2000s and then on a sea-level DynoJet of the same model. The uncorrected FM number was 190 rwhp, the SAE corrected value was 250, and the sea level dynojet was about 225.

--Ian

concealer404

iTrader: (3)

I did 245whp on the Rototest, spent 2 years fighting that piece of crap Hydra, had a Haltech installed and tuned, made a BUNCH more power.

Made 193whp on a Dyno Dynamics in Louisville.

Goodwood

Good info, thanks. The dyno at FM is a dynocom, I don't know anything about that brand. I was under the impression that dynojet dyno's read about 10% higher than factory pro dynos, and there's so many other factors that unless you're in the same place, same fuel, same temp, et all, at as close to the same time that comparisons aren't really accurate. Anyway, sorry to question whether a dyno chart is impressive.I'm unaware how my question is going to effect the owners enjoyment of his motor. If it works, and they're happy, good for them.

I looked at the efr kit from trackspeed, but clearly I am not an expert at turbocharger systems, and it not being a complete kit at the time I purchased my kit, wasn't what I was looking for. Maybe next time now that I have a bit more understanding of all the bits necessary for the system to work. The last car motor I built before the BP was a 455ci olds V8 back when there were 2 Germany's. It had a carburetor.

I am wondering about the 15 psi of boost really being 17psi of boost due to altitude, and what that really means. If the charge is at 2bar, why would it matter if it took 15, or 17psi to get to the 2bar? At sea level it'd take less work for the turbo to get to that point, but wouldn't the output be very similar? I once read in Road and Track that turbocharged F1 motors, in the old turbo era, worked harder, and made more heat at the race in Mexico City, but the power output was about the same.

"Lots of negcats for you sir" Did you just assume my gender? I have a cat, he's awesome. Kills all the damn packrats around my house. I don't feel like negcats will effect my enjoyment of the car.


"You should be very wary of sharing that dyno chart on this forum, since FM's dyno is notorious for reading extremely high" You asked if I had a dyno chart. Jeez.

Savington

iTrader: (31)

e: nm, don't feed the trolls

Goodwood

Damn dude, do you have such thin skin that you can't answer a simple question without attacking? Why do you get to be so rude, and condescending when asking for a dyno chart, then saying be careful about posting that dyno chart? Who the hell claimed any dishonesty? If it's so impressive, this was an opportunity to tell me, and everyone who reads this thread why it's it so. Instead you get a case of the ***. Quality.

concealer404

iTrader: (3)

I can only guess as to what i missed, but i imagine it was somewhere along the lines of:

1) You stated your car made more power at a certain rpm range. It didn't. Not even close.

2) Your chart even if the correction factor/dyno used were nearly equivalent, doesn't show a setup in the same league as what was posted in OP. (Which is true.)

And then maybe a snarky comment or two in the middle.

Goodwood

Pretty much nailed it. Except my dyno result was 376, OP 389. At 4k i am at about 155hp, OP at 189. I'm told the dyno is **** and it doesn't count except to boost my ego, and i have negcats. I'm told that my system is pants, and if I want to really be happy to buy vendors system, vendor then insults me. lol I get more negcats. I eat lunch.

concealer404

iTrader: (3)

Peak doesn't mean much of anything. I think that's the point that's being made here.

At 4k you make 30ftlbs less than OP chart had at 3800rpm. This isn't a small difference, and it would be larger if you were both on the same dyno.

OP carries power much farther than you do. Difference would be larger if you were on the same dyno.

The dyno you used is fine. It's just not comparable.

At the end of the day, people reacted negatively when you came in and pooped on a result. And now you're mad because it turns out you were wrong.

Your setup is fine, nothing wrong with it. It's just not comparable, so if you don't want more things like this to happen in the future, understand the difference.


This is like me with my Budget Bilstein coilover setup making snide comments about the double adjustable Xidas. "Well, MY setup ALSO suspends my car whilst in motion upon the ground!"

ridethecliche

iTrader: (2)

I mean... why would you expect any different when you're basically entering a pissing contest and your **** is off the mark?

You didn't come in here asking why that was impressive or questioning anything. You came here saying how something was not impressive because you were able to get in that balllpark with a different system on a different dyno. You were proven wrong. Now you're butthurt about the fact that your numbers are wrong so you're trying to save face a bit and have your tail between your legs.

Did I TLDR the last page and a half pretty well?

Goodwood

Fair enough. I was wrong about the numbers. I wasn't looking at my chart when I made the claim that the power was more at 4k, I thought I was closer to 200hp. Wrong. I feel like this thread has been completely highjacked, and I regret that. I'm going to try and let this die. :-)