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Dyno results are IN!!! for real this time!!


Guest bastaad525

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Guest bastaad525

OKAY hey I finally found a couple places nearby that have Dynojet chassis dynos! Gonna try to just get in a baseline run or three to see where I stand at the moment... not only power wise but to be sure I'm safe running 10psi w/o the intercooler seeing as it seems the actual install of the I/C I've had for MONTHS just keeps getting farther and farther away! And also just because I'm a numbers freak and dont like not knowing :bonk:

 

So... I'm hoping for like 200 at the wheels, but expecting closer to maybe 180 :( ... I like dynojet dynos because they are usually very optimistic :D I'm also expecting it to be a little lean at the top but since I'm NOT running an I/C... less oxygen getting into the cylinders with each compression, I hope it wont be to dangerous levels. I see no signs of lean running on the spark plugs so I'm not too worried. We shall see

 

Oh and on a side note... for the first time today I noticed that I totally screwed up with this glasspack I installed... I must have been really tired when I had this done... I got one of those crappy ones that has the 'fins' that stick up into the exhaust flow... so now I am convinced that I have just about the worst exhaust setup possible on this car... possibly even worse than it was stock.... from the downpipe there is a 3" crush bent piping that runs to about where the diff is... where I originally had the exhaust dump... then due to lack of funds, and lack of a place that could do more 3" (the place that did the first half was HORRIBLE and I vowed never to return) the last part of the piping is down to crush bent 2.5"... into that horrible glasspack... well at least I can be happy with knowing there is lots of easy, relatively cheap power to be had there

 

No wonder my turbo is so damn laggy..... on the flip side, as a little test I punched it at 1500rpm in 5th (totally lugging it I know), and saw that from that point I will hit full boost (10 psi) by 2000rpm! Normally at lower numerical gears it comes on later... like 2600... ah well it's neither here nor there...

 

so how much power you guys think I'm good for?

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hey, your predictions sound about right. On my very bad dyno pull w/o tuning the sds, and ignition problems at 5k I ran 182hp and 220ft/lbs at 8 psi on the stock turbo. This is intercooled though.

 

New turbo on the way and hopefully will get all my problems fixed or at least most of them 350hp here i come :twisted:

 

-Austin

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Guest bastaad525

Sorry guys I changed the topic name before typing up this reply and apparently more than a few people came to see the results during the time I was typing this up!!... sorry!

 

 

Wooowooooo good day good day...

 

 

well... first... the nitty gritty :twisted:

 

199rwhp @ 5200rpm

234rwtq @ 4100rpm

 

this is on a dynojet dyno btw

 

man did I call it or what :) well this was at the very top end of what I expected... given the vast number of other people here and at zcar.com that have dynoed very similiar setups I was expecting much closer to 180 or possibly even less. So needless to say I was very pleased with the results... this is 50-60hp over stock with nothing more than turning up the boost 3 psi! This is no I/C... crappy restrictive exhaust (SO much power to be had here!!)... worn out spark plug wires (!!!) and an EFI that is still pretty buggy.

 

Now some of the finer details.... torque comes on strong, early, as would be expected. It hits 220 lbft at 2800rpm, dips down a bit and stays above 200 all the way past peak and to 5000rpm where it finally starts to drop off... a nice, mostly flat curve. HP climbs steadily and then levels off at 4100rpm, rising only slowly to the 5200rpm peak and doesn't fall off at all by 5500rpm which is where I asked them to stop the pull. From 4200 to 5200 the HP is pretty much flat.

 

And then there's the bittersweet news... A/F ratio. When boost first kicks in the fuel goes pretty fat... gets down to about 10:1 AFR, and stays there til about 3600rpm and slowly starts to lean out. By 4500rpm it's about 12.5:1 and levels off until about 5100rpm where it suddenly starts rising again, up to 13:1 at 5200rpm. So here is another case of that lean top end showing it's ugly head after 5000rpm... I fully expected this... actually I expected it to go lean way before that point so I'm very happy with this also. So... how badly lean is 13:1? Am I in danger there?

 

I'm going to make upgrading the fuel pump my next priority, as the major oppinion from you guys on the forum suggests that it's the fuel pump running out of flow at that magic 5k rev point... I HOPE that this simple upgrade will be enough to take care of this issue.

 

We did three runs total with the first one being the best one, runs 2 and 3 both peaked a few less hp and ft lbs... I assume from the heat caused by the first run. I also tried run 3 with my 02 sensor connected (I've driven the car with it disconnected for months) just to see what I was 'missing' ... turns out.. not much. Runs 2 and 3 were nearly identical power and torque wise, but there WAS a notable difference the A/F. Especially in the mid range of like 3000 to 4000rpm the car ran quite a bit more lean... 11ish to 1 compared to 10ish to one with it disconnected... yet, on the low end it ran more rich... *shrug* above 4400 it was pretty much identical AFR between the two runs. Well.. there you have it... I'm a happy guy :)

 

I have a scanner that I haven't used in like 2 years... maybe later today or tommorow I'll get around to hooking it up and installing the software to scan the graph for you guys to see. I can never figure out how to post it where it will show up in the thread... I know how to upload stuff to my gallery here but it always just shows up as a red X, or just the link shows up and you have to copy and paste... I dunno.

now I NEED my fuel pump and I/C!!!

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Guest bastaad525

some other relevant details for tech minded people like me

 

it was a nice cool day.. I'd say low to mid 70's... dry and windy... and I'm in the valley so the elevation is very close to sea level.

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Guest bastaad525

damn... going back and reading some archived posts to get more educated on this A/F thing... Seems kinda odd to me that I"m getting so much variance in my AFR... from 10:1 to 13:1... most of you guys never see variances of more than .5:1

 

gotta wonder what that might be an indication of...

 

so guys do I need to worry about low 13:1 AFR's? I see most of you guys keep it in the 12's...

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Guest bastaad525

John K - most... not all

 

I still have to run with my O2 and TPS disconnected or the car misfires a lot and doesn't feel 'right'. Then there's also the strange problem of the TPS causing the timing to do strange things when it's connected. Even running it this way, it still has a misfire there at low engine speeds... I need to replace the MSD that I fried. There are other small issues... mostly with the EFI. Then other little things I need to take care of, like getting a new fuse box... and now I'm also turning my attention back to suspension... the eibach/tokico combination rocks, but are really highlighting the fact that the cars 30 year old bushings aren't up to the task... so those need to go soon. But yeah... it's been relatively problem free for some time now (KNOCKIN ON WOOD AS I TYPE THIS!!!!!) and has been a real joy to drive every day. At least now with the dyno I got to see what it's doing... I've been so worried that the A/F would be WAY off and that the power would be low as a result... glad that isn't the case.

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Guest bastaad525
Congratulations on the good numbers. Stoic is 14.7:1 so 13:1 isn't too bad. I think 12.5:1 is what most people shoot for.

 

alright I wont worry much about it then... it's a good thing though that I never rev past 5500... I went back and found this link right now:

 

http://www.z-parts.com/stuff/run1af-tor.JPG

 

this is a dyno graph of Tyson 280zxt's car... just shows torque and A/F. This graph is nearly identical to mine... he was running the same amount of boost as me, though his car was intercooled at the time. The torque and A/F curves match almost exactly... they took his all the way to redline though... and look how lean he got... all the way to 14.2:1 by 6500rpm :shock: I dont see a point taking it that high though it's just winding out after like 5500... and after looking at his chart again I dont worry about the big variation in A/F I got... must be a Z thang :-P

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Guest bastaad525
Congrats!!! :cheers:

 

Now the real question: If you had it to do over again' date=' would you???

 

Jon[/quote']

 

 

HELL NO!!

 

 

all the $$$, frustration, pain, days where I had no transportation, all the fear of 'when will it break down again... how long do I have?' (I STILL feel that way!), the mysterious bent valve, the mysterious burning oil... rebuilding the whole damn engine not by choice, the super buggy EFI... and like $10k+ spent on this car this year alone? No... I'd either have bought someones done or near-done V8 hybrid for like half that, been just as fast if not faster, and have technology that I actually know enough about to work on (4bbl baby!) or I'd have put the ten g's as a down payment on a shiny new 350z. I love the car... dont get me wrong... but the money and time could definately have been better spent. Not that I'd ever dissuade anyone from doing a turbo swap... I just had a tremendous run of bad luck with mine.

 

god it's gonna know I'm talking bad about it and break down like crazy now watch....

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Guest bastaad525

another question... where do you guys think my optimum shift point would be? Figure with my tranny and diff, the RPM drops almost exactly 1000rpm with each shift... the dyno guy, after checking out my graph, says 5500 would be best... but I'm thinking even earlier at like 5000 or possibly even earlier? I want the after-shift RPM point to be on the upswing of the torque curve right? I've heard so many differen't 'methods' I forget which ones actually make sense....

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Guest bastaad525

if I'm not dead tired when I get home from work tommorow morning I'll dust off the scanner and get it loaded up. That graph of tysons though is really really very close to mine... even the actual numbers (230lbft vs 234... very similiar rpm peaks... and his A/F matches mine 95% exact, both the actual numbers and the shape of the curve)

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Guest znow white

congrats man :rockon: I think those numbers are good and will get much better soon as you intercool! :twisted: the only downside is you spent allot of money (10k just making sure its not a typo) is that including your old NA motor and labour cause that seems high.

Iam planning to my turbo swap as soon as I can find s30 chasis and your expenses are scaring me I hope I dont run into that much bad luck. :?

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