Finally got to dyno

[WAbernethy]

Well I finally got everything straightened out with my "junkyard turbo" setup, except for that pesky oil leak. Anyway, I was kinda depressed with the numbers overall. 161 Hp/186.8 ft/lbs at the wheels. Not sure what this relates to back at the fly but it's a little lower than I expected. The guy that tuned it for me said that the computer was only showing 5-5.5 psi, my gauge reads more like 7-8psi. Maybe I'm just getting less boost than I thought.

Anyway, just wanted to know what you guys thought. The shop I went to has a Dynapack chassis dyno. Anyone have any experience with these?

[95_240sx]

Where is the feed for your boost gauge at in association with where they had theirs at?

Rick

[crzycav86]

How much did it cost?

There's a phillips 66(i think) near my house that charges 27 dollars. I'm not if thats per pull, or whatever, but I thought that sounded like a pretty good deal

[WAbernethy]

My gauge is hooked up to the vac line that used to go to the EGR valve. He t'd off of one of the hoses near the fuel rail.

It cost 120 bucks, ouch, but he did like 6 pulls and tuned my safc with their wideband setup. I think it was worth every penny.

[Checkered-Member]

dag well your tq figures look good, the low hp might be because of an error in the computer,

what was humidity?elevation? temperature?

[theronin]

that seems rediculously low. make sure you dont have a boost leak or something.

[S14tat]

wow you got your car dyno tuned for only 120? holy **** i had to pay 250 for my tuning but i had 23 pulls anyways for 5 psi, you should make more then that tuned. cause 160 something at the wheels is rediciously low for 5 psi. you should be close 190-200 at the wheels with that boost tuned. if your makin 160 at 5 psi untuned then thats more understandable. how much power did you gain from the AFC tuning?

[4felix20]

what kind of parts are you running? maybe the turbo is crappy or something...

[WAbernethy]

I'm using a CT-26 from a Supra. It's not he best turbo for sure but it does make full boost from about 2500 to redline. I'm using 2" piping and running it through a starion I/C. My bottom end is original but still holds about 160 psi on all cylinders. Not sure about the humidity or pressure, but it was cool out, about 70 degrees. As far as having a boost leak, wouldn't that be rather noticeable? I mean, it seems to make boost quickly and holds it well. Wouldn't I have heard something while it was boosting on the dyno? I was looking under the hood while it was under full throttle/load. How can I check for this?

We gained about 20 hp overall. We tried to go a little leaner but got slight detonation. The readout from the wideband stays between 12.2 at lower rpm's to 11.6 at higher rpm's. I think it's tuned pretty well.

Back to my original questions, Has anyone dealt with this type of dyno setup? I'm wondering if this is one of those that reads lower figures when compared to others. What's the average power loss through a manual transmission?

I know the numbers sound low but it pulls like a crack whore on a glass pipe. Still haven't found anyone that wants to have a little showdown so I don't have anything to compare it to but time will tell. I did have some redneck in a full-size Ford try to take me but that was a joke. Had him by 3-4 carlengths before I got out of 2nd gear.

[S14tat]

the average powertrain lose for any transmission is 7.5% per set of gears. since a RWD has 3 set of gears, thats one input shaft, one counter shaft, and one output shaft. that equals to around 22% power train lose. so your probrably making 200 and change at the crank.

[andrave]

I was thinking dynapack was a brake dyno and not a chassis dyno, I thought dynajet was the chassis dyno.*shrugs*maybe I don't know what I'm talking about.

[NateDogg]

You hp is low due to your compression reading. Should be around 175-180 if you want better power. Take it easy on that old girl or just turn up the boost and put her out of her misery. Does it use a lot of oil?

[Nathan]

22% powertrain loss? Yeah...if he bolted 100lb. weights to his driveshaft or something...and 160 psi isn't all that bad, it should be 175-180 when it's BRAND new. That's not a huge difference.

[WAbernethy]

It uses very little oil. Maybe 1/2 quart between oil changes. Not sure about what type of dyno it actually is. It's called a chassis dyno by the company that owns it. http://www.eurospeedperformance.com

[TurboKA37]

what did the dyno graphs look like? pretty smooth? when do u make max hp?

[WAbernethy]

Yeah, it's a nice smooth curve all the way to about 5300rpm and then it starts to drop slowly. I'd post them but I haven't scanned them yet and I don't have anywhere to host them anyway.

[TurboKA37]

im thinking its the turbo. all i really know is mainly the t3/t4 turbos so i dont know much about the one you are using. the fact that its spooling by 2500 and making alot of torque im thinking its not flowing enough in the higher rpms

[S14tat]

how is 22% unrealistic? when you look at a power chart for a mustang, or any other rear wheel drive car, you times the wheel hp by 1.22 and you get a number very very close to what the advertised crank hp is. i don't know where they got the number from but thats what i learned in school ( automotive engineering tech) i know i'm nothing compared to some of the more hardcore guys here, but that numbers been proven to be a pretty close power train lose. you can even do it with FF's since FF's only got 2 sets of gears, the input and output shafts, its usually a 15% power train lose. and if you do the same thing to most FF cars the wheel hp will match the crank hp. i didn't make this stuff up.

[WAbernethy]

I don't see how it could be the turbo. If the boost holds all the way to redline, it should be flowing plenty. I know it's small but I'm only asking for 7psi. I thought that if the turbo was too small, boost would dropp off at higher rpm.

[TurboKA37]

holding boost doesnt have much to do with it. its more the turbo's efficiency range and turbos that spool quickly tend to become inefficient at higher rpms. thats why the huge turbos u see on supras highly modded supras and such have very bad lag but create enormous emounts of power at high rpms.

[Turb0wned]

how much did you pay for the turbo?

[WAbernethy]

OK then. When a turbo has exceeded it's efficiency, what are the symptoms? Exccess heat and the inability to produce boost at high CFM's. Maybe I'm just misinformed. I don't think I'm having a problem with either at only 7 psi. My cold side feels cool even after hard runs and I'm not having trouble with detonation. This turbo is big enough to feed a small 6 cylinder at 7psi, why would it be too small to feed a large 4 cylinder?

[TurboKA37]

we'll have to get a NICO certified turbo expert in here. too bad WD has been gone for a month and a half

[andrave]

if you used a very small turbo it could easily run out of steam at higher rpm's. on a relatively small sr20, the stock turbine runs out of steam pushing past 10 pounds at redline...

on a much larger 2.4, the problem would be multiplied. of course thats with a tiny lil T25 too.

[TopStreet240]

the turbo is not the issue unless it has some major shaft play. My shop deals with a lot of turbo supras and one of our guys was easily putting 15psi out of the turbo. The turbo should be more than capable of running the 8 psi you are looking for. What kind of exhaust are you running (this could be a loss in the power) what kind of intercooler and piping, also i would check for a vac. leak. sometimes you cant here them but they can really cause some major power loss.

[Nathan]

22% is just a good bit higher than the commonly held 14-17%, even for a fr setup. It's not like I have any data to back this up except knowing one tuner (Bob Norwood) who uses 16% pretty much across the board, but especially when he tuned a nice old school Supra. If it's good enough for Bob Norwood...it's good enough for me! The bad thing is that if differs across EVERY car since there are so many factors that affect it right down to the transmission or differential oil used. The only way to find out is to do a engine dyno, then a chassis dyno

[S14tat]

well i guess its all up to who you want to listen to. cusae this is what i got from my text book and professor and from my boss and DRT lolz:icesangel

[WDRacing]

Ok, I'm finally back. I wouldn't say it was the CT26. I had one of those little bastards cranking out 20 psi on a 3SGTE MR2. It did have some drop off at higher rpms but it was still using the stock wastegate aswell. I know the 2.4 is 23% bigger, but 5300 rpm is very low in terms of a built motor, unless your talking in terms of big blocks. Anywho, 160 static CR doesn't seem all that bad. I've boosted worse. It would be most helpful if I knew what the car was doing prior to the turbo install. Thats most likely where all the keys are lying. Its very important to dyno your car at each stage of development that way you can maintain some kind of baseline for your modifications.

I would also like to see your dyno sheet. With a turbo that size the torque line should go verticle at 25-2700 rpm and stay there till around 45-5000 rpm. The horse power should follow a some more lazy curve but similer.

You should expect 10 hp per psi of boost after a turbo install.

What were your EGT's?What was your A/F curve?We're they getting any knock?

WD

[TurboKA37]

OMG!!! WD ive missed u! i was starting to think u were killed in a top secret spy mission or something! and the KA-T section has been a little lonley without you. how have you been?

[WDRacing]

Back for good bro...