so i finally take my car in to get dynotuned with my safc 2.
[mods:cattman headers/downpipe, unorthodox udp, k&n universal cone, advanced timing 17*, motegi liteweight 16s, apex'i s-afc2 ]
and after an hour of tuning this is what happened.



the tech smoothed out my dips, actually made my car run richer than
normal... ran it a bunch of times with a little improvement, [2nd highest run had 251 peak] mainly smoothing out my lines. the numbers started to dip as a whole, [power curve looked the same] so after the 10th run, he said my car could use a minute to cool down a bit. after 3-5 minutes, he came back, did one pull, and i got an overall 15.7 hp increase and a 23.5 tq increase there's a gap around 5.7k rpm, the tech said i probably had a misfire somewhere. should i worry?

it's weird..you can see my a/f doesn't have any major modifications, but i'm VERY happy with the final number i put down.

i don't know much about sae correction, and i realize that these numbers probably aren't corrected, but even UNcorrected, i'm impressed by these numbers. what do you guys think? [it was drizzling when i got dynoed, and my car comp said 71 deg. i'm in san bernardino, ca. ]

 

That rules! What did you think the #'s would be before you did it?

 

Absolutely incredible. If you can run those numbers on a track, it'll place you well into the 13s.

 

Do you have the run files? I'd love to take a look at em.

Also, most people here use SAE correction as opposed to STD, so I'm not sure how comparable your numbers are to other people on the .Org.

 

sorry, just got a printout.

yeah, can anybody explain more about std vs. sae? how to correct for each. i know there's a million factors going into dyno numbers, and i would like to get a better idea of how i stack up against other max's. [can't help it... i wanna feel proud, but i dont' wanna jump the gun.]

 

WOW! Very nice numbers! Can't wait to tune mine!
So would that be like 300hp at the crank?

 

nice... i'll try and get 'em

 

Will, do you not have an aftermarket cat-back? I guess that's what you implied by not mentioning any other exhaust mods in your list.

 

http://www.forums.maxima.org/showthread.php?t=400820
The #'s in that chart are corrected.. STD.
Interesting.
Most likely Knock/detonation due to heat.

So you do not have any sort of cat-back.. Another interesting fact.


Also, the actual data #'s wont read past 57xx on run 11 because the RPM signal wire was not connected correctly.

The runfiles would help

 

my cat and b-pipe are stock. the previous owner put some no name muffler on there [i wanna switch it back to stock and get a cattman b-pipe]. plus, headers/downpipe from cattback like i mentioned before.

what's wrong with the data past 57xx? didn't quite get what you were saying. sorry... total noob still. i'll get those run files as soon as possible.

 

from what i understand dynajet runs a little higher than actual street numbers. several of my friends suggested using mustang dyno, because it's load compensated, and reflects truer numbers you would get driving down the road. anyone have both done, and can verify if there is a difference b/w dynajet vs mustang dyno?

 

I've actually known people to dyno both higher and lower on a Mustan dyno compared to a Dynojet.

Dynojets do dyno a little higher on average, but its all dependent on the settings used on the Mustang dyno you're comparing. The numbers can be comparable if the load settings are done right. More often than not, they are not comparable, esp not on the .Org. Take a look around the dyno forum, I think there are at least a few threads talking about the differences between the 2 that might give you more info.

Dynojets are commonly used for people to play the internet dyno game; as a way to compare whp with other people. It is kinda like a benchmark and also seems like the most commonly accessible dyno out there.

 

Thanks. That's what I thought.

I think Nmexmax was trying to say that the break in the hp and tq lines past 5.7k might indicate the RPM wasn't being picked up, in other words, they didn't hook the sensor up right.

 

looks like a small shot of nitrous to me, no way you pick up all that torque and hp from tuning especially when the a/f is almost untouched and the timing can't be adjusted. Why did the pull start around 4k and why did the a/f get so lean? That looks exactly like my dyno when I hit the juice with the stock fuel system/pump.

I'm just not seeing that big of an increase from just tuning with an safc-2 especially when the timing can't be touched and the a/f is on par from the earlier run.

 

Great numbers, but he won't be touching 13s for a while.

 

the first set of numbers are realistic and on par with all the other cars with his mods STD corrected. The so called "tuned" numbers are not realistic or believable in my opinion as per my previous post.

 

no nitrous, no FI at all. i'm actually a big fan of the n/a maximas, and trying to get in the 13s n/a. [apparently people have differing views if my car can do it yet]

like i said, i was surprised too...[the title of my post]. the second highest run was a peak of 251, which had a similar curve, just lower peak. after ten runs, we let the car sit for a while, the tech said it was getting too hot. after a few minutes, we came back and did one last run to see where we would be at... and got this. [the increase isn't all from tuning. as mentioned before, tuning basically smoothed out my curve, getting rid of dips. the increase in hp probably had lots to do with the break, and the drop in temperature outside. the run starts around 4k because the tech took 3rd gr. pretty high up the tach before shifting. i just thought that's how you do it. still a noob, please educate.

regardless. in optimal conditions, i was very pleasantly surprised at the numbers my maxima put down. i'm still working on getting those runfiles to see how my sae numbers stack up, like puppetmaster said.

again. no nitrous.

 

well why didn't he do it on the first run? please educate. Those torque numbers make no sense especially gaining 25+wtq low end by just letting the car cool off.

 

You should be able to get deep in the 13's n/a if your car realisically makes the numbers posted and its not some HUGE correction factor or fluke. You are making 20+ more wtq than any other NA 3.5L Maxima no matter what mods they have. SR20DEN makes around the same hp number about 4whp higher STD but his torque is about 20wtq lower. Makes no sense and its not really possible without some assistance.

 

hahah ... i'm sorry i can't explain it. i wish i can prove to you somehow that i was n/a, and all it was was a break/drop in temp. maybe it was a fluke... again....

I WAS ALSO SURPRISED.

i should be installing a b-pipe in the near future. i guess the best way to find out would be another dynotuning sess. see where my numbers land.

 

well the torque number is whats in question mainly, its possible to make 250whp SAE if these new cattman headers are as good as they are marketed to be but gaining that much torque is just not going to happen period from exhaust bolt ons.

 

Have you tried getting the run files?

 

it seems your still at a 12.7 to 12.5 AFR at PEAK whp...and still putting out 261whp/261wtq? seems high as hell to me....just for comparison, I have the same setup as you willkim (with a bpipe), and I dynoed 245whp/247wtq SAE....I remember i viewed them in standard as well...both hp and tq shot up another 8 or so....your still dynoing alot higher than the average max....

maybe some track times would put this to rest? if his trap speed is really high, then that will prove that he's making the power he is on the dyno

 

WILLKIM- are these the new generation cattman headers? thats quite impressive if it is....maybe puppetmaster will be in for a suprise when he dynos on the 8th

 

It will be the typical hey look at my awesome dyno numbers, my car trapped 100mph.

 

if he tracked his car....and trapped at 103-104...would you buy that hes making the power he really is? or your confident he won't be trapping that high?

 

it all depends on the elevation, car weight, and outside temps at the time of the run. With an approx 2000ft abs and normal car weight and 70 degree weather the car should have no trouble trapping 103.

 

If the rpm signal wasn't tapped properly, the torque numbers can be skewed.

This happened to a few members at a local dyno meet at R&D Dyno. I was putting down 26x tq figures on a stock maxima

 

I saw a dyno run file that showed this. .. and also, it(OP's dyno) wasnt connected correctly due to the cut out of data at 57xx.

I've seen an A33B put down over 300 ft/lbs with only ~240whp....N/A...

 

These power numbers put his power to weight ratio close to where my Trans AM was in stock trim. I dyno'd 264 in stock trim and was trapping at 100 to 102 mph. His power to weight ratio is a bit better than mine was, but he definately lacks the low and midrange torque my TA had. Having said that, with the power he's making assuming he can drive trapping at 100 to 101 should be fairly easy...103 to 104mph I would think would require closer to 265 to 270 rwhp in the these maximas.

 

I think the issue is that the horsepower figures are derived from the torque output on the dyno jet (IIRC). So if the signal wasn't tapped correctly, people are in speculation. This is especially true since there was only a simple cool down and fairly rich A/F (plus not much correction made to it from the base run) to contribute to such a large gain.

 

called the shop this morning, gave them my email address for the files. still no word. i'll let you guys know as soon as i know.

yes they are. i was the lucky guy who got a free install down in san diego by cattman's old shop.

that means in std you were getting ~253whp and ~255 wtq. not THAT far off what i have. also... don't make wheels make a big difference? could the extra 5-6 whp/wtq i'm getting be 'cause i'm running smaller lightweight rims? [16"s, <15lbs.]

i agree with everyone in that these numbers are suspicious. but this was the end of a tuning session, and all the numbers were looking "realistic" until run 11. maybe during the break the rpm signal was knocked or something. i'm gonna talk to the tech about all the controversy i'm causing and try to get a couple free pulls to settle this. i already mentioned somehting to him, and he seemed a little offended that people would question his methods.. haha.

i also want to take it to the track as soon as i get new tires.
.. for arguments sake.... IF these numbers are realistic... and IF i know how to drive... i should be trapping 101+ mph with street tires?

 

If you have the power, you won't need to know how to drive. The car will determine your trap speed. The E/T on the other hand will be attributed to your driving

 

That's actually a pretty good theory...

 

Considering how low rbrown81's numbers were when he first dynoed em, I'm still not gonna get my hopes up. Esp not with the debate going on here now.

 

yeah...

talk about a burst bubble.



i'm gonna try and get a few more pulls in with a b-pipe and get some trap times.

i'm still hanging on to the slim hope that these numbers are legit.
but i'm probably gonna be when i see a few more pulls and a trap time.

 

just talked to the tech. he told me about run 5-6 he realized the ac was on

the next run... he got about 6-7 more whp and wtq.

wtf is going on here. i wanna verify or find out what my car's really putting out.

 

waaahhh? Hopefully you get compensated with some free runs. The A/F could be a bit higher and the b-pipe will give you more area under the curve

 

[QUOTE=willkim]that means in std you were getting ~253whp and ~255 wtq. not THAT far off what i have. also... don't make wheels make a big difference? could the extra 5-6 whp/wtq i'm getting be 'cause i'm running smaller lightweight rims? [16"s, <15lbs.]QUOTE]

thats true...but i still have a hard time buying it...your making 261whp STD with a 12.7 AFR...thats on the rich side (lose hp)....i'm making like 253whp STD with a better AFR than that....I can't clarify what AFR i was at on that run...but I know it was nearly perfect....within 13-13.5

I also have a bpipe and you don't....but i'm still putting out less hp than you...I know a bpipe alone wouldn't be something to talk about...but we are both bolted on and tuned....enough to bring out noticeable power in a bpipe

 

Those are awsome #s!! What does a stock motor put down with an auto tranny?