Analyze this

[Bernardd]

I dyno'd my car friday nite. She put down 293hp @ 6k and 268 ftlbs @ 5200. I haven't scanned the sheet yet.

Mods:

z31 ecu

z32maf

holley 255lph hi press pump

440cc injectors

2.5 to 3 in downpipe with 3in piping (pressbent after trans x member)

pod air filter

gn intercooler w/ 2 in piping from turbo to stock tb

t04b 60-1 compressor/ .81a/r stage 3 hotside

stock wg actuater with adjustable arm for boost control

egt gauge.

progressive alky system, with m10 and m15 nozzles spraying -40deg ww fluid (70-30 mix)

rebuilt jatco 3 spd with a 2.8k stall and b&m shift kit.

ngk 8-11's gapped at .035

 

The dyno was the mustang type. I was unable to increase the power with changing afr's and/or timing. I did gain about 30hp with increasing the boost by 2psi. Afr's were kept at12.1- 12.5 with 22deg advance at max boost. I cannot say what the actual psi was but the boost was off the 20psi of my gauge. I've tested the gauge against others and it seems to be 4psi generous at 19psi. I'm guessing it to be about 20-21psi. One thing that puzzles me is that the maf readings where lower on the dyno than on the road. The voltage dropped to 4.0vdc during the first runs on the dyno, while the same boost settings resulted in 4.2-4.4 during road testing. The 2 psi increase brought the maf readings back up. My timing chain is stretched a bit with pos 2 resulting in a deg or two of retard (power shift to higher rpm) and pos1 resulting in about 5-6deg's. I know I can improve the setup a lot with better piping but it still seems like the torque is way low.

Bernard

[AnTmanS130T]

Your Hp seems ok but your torque seems very low.. I am running around the same setup yet out of all 5 graphs my highest hp was 270 / 322 torque on about 16psi 93 octane. I am sure you seen my thread and maybe we can help each other out. I know you talk to my friend Bryant (Stinky) a lot about tuning due to the fact of him messing with the z31 ecu's a lot. He is the one that is helping me right now..

If you have aol instant messenger hit me up at Hallucinationed1.

[Pyro]

Good hp but as you already know, that torque is pretty low. Should be 350ftlb! Are you sure you are reading the dyno sheet right?

 

I think your biggest problem is the stock wastgate. The turbo exhausting directly into the exhaust pipe is much better than dumping into the open volume of the stock wastegate then necking back down to get down the exhaust pipe. Not a big deal at lower hp, but starts becoming a restriction at higher hp levels. That could be hurting the torque???

 

Here is another one for you Bastaad525. 293hp at 20 psi of boost

(20 + 14.7)/14.7= 2.360

2.360 x 125hp = 295hp.

And the other post "Dynoed the 280". 270hp at 17psi of boost which is also just about right. 2.156 x 125hp = 269.5 hp

 

That formula is rock solid!! Why can't you see that??? hahahaha

Remember 125 hp base for a stock L28 then do the boost multiper. Works everytime!

[yo2001]

the torque is low due to late torque peak.

 

Nice number considering Mustang dyno reads pretty low.

[Sean73]

Bernard -

 

My torque was also low: 232HP / 232 TQ.

 

I attribute this to dyno operator error / inexperience. He accelerated too gradually, failing to build boost at low RPM, resulting in a gradual torque rise, and late torque peak.

 

Had he floored it, boost would have maxxed instantaneously, and I think I would have seen an earlier torque peak.

 

I'm looking forward to seeing your chart.

 

Sean

[SleeperZ]

Bernard -

 

My torque was also low: 232HP / 232 TQ.

 

I attribute this to dyno operator error / inexperience. He accelerated too gradually' date=' failing to build boost at low RPM, resulting in a gradual torque rise, and late torque peak.

 

Had he floored it, boost would have maxxed instantaneously, and I think I would have seen an earlier torque peak.

 

I'm looking forward to seeing your chart.

 

Sean[/quote']That sounds reasonable, and may bring the power peak back down. I was running a stock engine/cam/turbine when I dyno'd last year, getting a comparable hp figure and monstrous torque.

 

420 ft-lbs at 3500 rpm, 314 hp at 4500 rpm.

 

At 5500 rpm, when the dyno operator stopped, my hp was 290, and torque had dropped to 275 ft-lbs.

[SleeperZ]

I just noticed the boost level you ran at, Bernard. A 60-1 compressor should be able to make that power at 15 psi, where is your system restricted?

[AnTmanS130T]

That sounds reasonable' date=' and may bring the power peak back down. I was running a stock engine/cam/turbine when I dyno'd last year, getting a comparable hp figure and monstrous torque.

 

420 ft-lbs at 3500 rpm, 314 hp at 4500 rpm.

 

At 5500 rpm, when the dyno operator stopped, my hp was 290, and torque had dropped to 275 ft-lbs.[/quote']

 

 

I hate to say it but your dyno numbers don't match what you ran. Are you sure the 314 / 420 was not a spike or ignition glitch. A friend did 400 ft / lbs on a stock T3 on a error spike. Post your graph if you have it. Usually a obvious spike is that one spot making those numbers and the rest of the graph level off and far from that one spot. I don't see how you ran a 12.8 @ 110 with that much power. I put down more power than a 280z last week and he has ran a 12.7 @ 108..

[SleeperZ]

I hate to say it but your dyno numbers don't match what you ran. Are you sure the 314 / 420 was not a spike or ignition glitch. A friend did 400 ft / lbs on a stock T3 on a error spike. Post your graph if you have it. Usually a obvious spike is that one spot making those numbers and the rest of the graph level off and far from that one spot. I don't see how you ran a 12.8 @ 110 with that much power. I put down more power than a 280z last week and he has ran a 12.7 @ 108..

I'm not sure what you mean. The dyno sheet and my time slips are real, and not that I'm a great driver, I get 1.9 second 60' times. Maybe because I run at 5800' altitude?

 

I had a scanned dyno plot that was posted here, but now it's not here any more. It's been two years. It wasn't a "spike", this dyno session comprised 5 pulls, all within 10% of each other. Until I rescan the sheet, I'll describe it to you.

 

The torque rises linearly from 150 ft-lbs at 2000 rpm to 400+ at 3300 rpm, runs flat to 4000 rpm then drops linearly to 275 ft-lbs at 5500 rpm. The hp starts at 60 at 2000 rpm and rises linearly to 270 hp at 3300 rpm, and continues to rise slowly to 320 peaking at 4500 rpm, then fades to 280 hp at 5500 rpm.

 

Keep in mind, these are corrected numbers for 5800 feet altitude. I don't know if they reflect what the car will do at sea level or not, that depends on whether my injectors and ECU would support the airflow, but that should be a minor point as we are talking about my T3/TO4B V trim, stock head, engine and dispacement with all the intake (3-1/2") and exhaust (3") restrictions removed.

[Bernardd]

Bernard -

 

My torque was also low: 232HP / 232 TQ.

 

I attribute this to dyno operator error / inexperience. He accelerated too gradually' date=' failing to build boost at low RPM, resulting in a gradual torque rise, and late torque peak.

 

Sean[/quote']

 

He let me drive the car. Which would make your statement 100% true. I rolled into it until 45mph then floored it. My torque converter allows the rpm to shoot straight to 4k and full boost is right behind it. The torque maxed at 5200 during all the runs, hp climbed steadily until end of the run at about 6k.

SleeperZ: I'm running 2" IC piping and the stock tb. My exhaust is 2.5 to 3" mandrel until just after the tranny case, then it's 3" press bent out the back. Several of the guys I know are in the 11's with these tranny's have dyno'd either lower or just higher than me so I'm not too worried about it. I am going to remove one restriction at a time and see what makes the most difference. I'll try and scan the sheet tonight and post it up later.

[Guest bastaad525]

 

The torque rises linearly from 150 ft-lbs at 2000 rpm to 400+ at 3300 rpm' date=' runs flat to 4000 rpm then drops linearly to 275 ft-lbs at 5500 rpm. The hp starts at 60 at 2000 rpm and rises linearly to 270 hp at 3300 rpm, and continues to rise slowly to 320 peaking at 4500 rpm, then fades to 280 hp at 5500 rpm.

[/quote']

 

That sounds exactly like my dyno curve... except your's is about 80hp/100ftlbs higher !!!!

 

 

Sleeper that is a very "T3" curve... you making that high number with stock T3???

 

You know sleeper, I've always been very curious about the details of your setup... the only thing I know is that you're running a 300zx MAF/ECU.

[Bernardd]

dyno graphs are up:

http://album.hybridz.org/data/2/medium/graph.JPG

http://album.hybridz.org/data/2/medium/graph_2.JPG

 

interesting note: I couldn't run the same amount of boost as what I ran on the dyno. Maf voltages went up to 4.6vdc, and I got some knock. I had to lower the boost a bit. I'm not sure how dyno's work exactly but my beside the fact that I had a great time, I don't think they load the car the same as on the street. I think I'll explore the limits of the engine setup at the track from here on. It seems like a waste when the setup on the dyno won't work the same as on the street. That's my gut feeling.

[SleeperZ]

That sounds exactly like my dyno curve... except your's is about 80hp/100ftlbs higher !!!!

 

 

Sleeper that is a very "T3" curve... you making that high number with stock T3???

 

You know sleeper' date=' I've always been very curious about the details of your setup... the only thing I know is that you're running a 300zx MAF/ECU.[/quote']

It's a hybrid turbo with a stock T3 turbine and actuator, and a V1/V2 trim compressor. I am running 370cc SVO injectors, a Z31 MAF element imbedded in a 3-1/2" intake pipe, and I tune the WOT mixture with an adjustable FPR. My intercooler is 2" inlet and outlet (Spearco), and it opens gradually into a 60mm Weber TB on a N42 intake manifold, port matched. Stock exhaust manifold, port matched to the turbo, a 2-1/2" stainless DP opening into a 3" mandrel bent exhaust and a 3" Dynomax Ultraflow muffler.

 

Stock '86 Z31 turbo ECU, stock Z31 ignition, stock timing.

[Sean73]

Bernard, - did you make note of when you reached full boost?

 

In your dyno chart, torque is rising in parallel with HP, between 4000 and 5000 RPM. This seems to indicate that boost was also rising.

 

Here is my chart, running 10 psi. At 4750 RPM, I am at about 230 lbs of torque. On your chart, you're making about the same torque at the same RPM. But you said you were running 20 psi? There's no way we could be making the same torque at 10psi and 20 psi respectively, unless you were not at full boost, or there is a big discrepancy between dynos.

 

[Afshin]

Bernard, I think your torque converter not locking until 4000RPM has a lot to do with it. I imagine the peak torque to be around 4500 rpm . I would not be surprised if the current dyno graphs more so reflects boost build up with max boost coming on at about 4800-5000rpm. Also, it is not uncommon for a dyno to be off by huge margins, specially if it has not been calibrated....

Also, looking at the graphs, I don't think that the main culprit is restriction (However, you should get ride of the 2" piping, at least with 20psi of boost). You have too much power in the higher rpms and climbing hp as well, I would expect the hp t be falling off much sooner with any major air restriction. I would not trust that dyno run sheet for anything!

 

Also sleeperZ, I was just thinking about the correction factor for the dyno run you had, if it was the standard correction factor for a non-turbo car, it could be significantly off, since NA cars lose much more power with altitude (they can't pressurize the air and make up for lack of barometric pressure and hence air density at altitude).

[Clifton]

Your HP still seems a little low considering the turbo even on a Mustang dyno. Your torque would be higher if the boost came on earlier though. Looking at the torque curve it looks like full boost is around 5200 rpms. Is that right? What gear were you in? If it was second in an auto that might explain the late torque curve. Not enough load. Your HP might not even be peaking at 6K, looks like it is just starting to get into it. The .81 with a stg 3 wheel will make alot more power up top than a standard T3 wheel. I would of run it to atleast 7k. I would think it would pull hard to aleast that on the street.

[Bernardd]

My muffler was badly collapsed inside. The opening was about 1.5 to 2". Right now I don't have a muffler and it spools a lot better.

[clint78z]

SInce you run the 300zx ecu, I would check to see if you are running enough ignition advance at lower rpms. The older L head really benifits from quite a bit of advance because is doesn't have the newer fast burn chamber like newer cars. An A/F ratio would be helpful on the graph as well !!

[Bernardd]

SInce you run the 300zx ecu, I would check to see if you are running enough ignition advance at lower rpms. The older L head really benifits from quite a bit of advance because is doesn't have the newer fast burn chamber like newer cars. An A/F ratio would be helpful on the graph as well !!

 

I don't have a graph but I can tell you that afr's where 12.3-12.5 from 3500 to 6k. Before boost timing is around 45-50deg's. At that time I dropped the timing to 30deg's from about 5psi to 15 psi, then at 20psi I dropped it to 24deg's. I run 36deg's right up to 20psi now.

[Pyro]

I guess you just need to re-dyno it without that bad muffler. I bet the torque picks up.