T-3 Super 60 Dyno numbers using JWT ECU program

[fastpace]

Well I have had my turbo setup for almost a year and have finally dynoed my car. I was happy with my results, but glad that I know where it is at now.

My setup:JWT ECU w/ 50lb programCobra MAFS550cc injectors255 lph walbro fuel pumpTurbo: Super 60 T-3 turbo

The first lines are at 7psiThe second line is at 11psiThe third line is at 13 psi

It seems like the turbo is coming alive after every increase in boost level, but the big problem is the a/f ratio, it is just crazy, at 3500 rpm the a/f ratio is below 10 a/f. Looking at the 3600 rpm level the horsepower and torque curve drop until 5200 rpm. It must mean that the a/f ratio is significantly lower than the 10. There is easily power to be had from all three boost settings. All three pulls were done on 3rd gear. In the mean time I plan on getting a safc to improve the a/f ratio, which should also improve throttle response.

Let me know what yall think about the dyno numbers.
Modified by fastpace at 11:29 PM 5/21/2005

[Nismo_Freak]

Something is very wrong.

Check your MAF voltage and your plumbing for leaks.

You can blow your engine running that rich.

[klattr1]

well, i know usually the JWT 50lb program is meant for t3/t4 turbos. maybe your car just isnt providing the amount of airflow of what the program is intended for (less air, same fuel, super rich).

best way of fixing it is gonna be by logging airflow (mafs voltage), injector pulse width, and the wideband air fuel ratios according to RPM and then having JWT reprogram it based on your setup. but the thing is, where do you even to begin with the fuel if its so far off the chart. i wonder if any gauge can register it.

you'll be alot happier doing it this way than correcting with SAFC even though it might take a week for a chip to come back.

also, whats your base fuel pressure at?

are those 550cc injectors side feed 550cc's or top feed 50 lbers (really 525 cc)?
Modified by klattr1 at 8:10 PM 5/21/2005

[nissanfanatic]

yea man. THats nasty. You're losing major power from running too rich. Prolly washing oil off of hte cylinder walls in the process. Def get that fixed ASAP.

[fastpace]

well, i know usually the JWT 50lb program is meant for t3/t4 turbos. maybe your car just isnt providing the amount of airflow of what the program is intended for (less air, same fuel, super rich).

best way of fixing it is gonna be by logging airflow (mafs voltage), injector pulse width, and the wideband air fuel ratios according to RPM and then having JWT reprogram it based on your setup. but the thing is, where do you even to begin with the fuel if its so far off the chart. i wonder if any gauge can register it.

you'll be alot happier doing it this way than correcting with SAFC even though it might take a week for a chip to come back.

also, whats your base fuel pressure at?

are those 550cc injectors side feed 550cc's or top feed 50 lbers (really 525 cc)?

Modified by klattr1 at 8:10 PM 5/21/2005

The base fuel pressue should be stock, I don't know what it is though, just installed the injectors on stock fuel rail.

The injectors are 550cc side feed injectors. That could be a problem also, but I think it is just the mixture is just too rich.

[Structure240sx]

good numbers for running so rich, how does it idle?

i cant wait to get my super 60 on my s13

[s13sr20chris]

im thinking part of your problem is 550cc injectors on a 50lb tune. you need a fuel controller and a ajustable fuel pressure regulator.

[MarkEmark]

Wow, that is super-rich...makes me nervous because I'll be running the same program with the same turbo, at least until I have the money to upgrade it (which will not be any time soon, my engine rebuild cost me $2100+ not including parts).

The thing with the JWT program is that with the 50 lb tune, most people are running like 15 psi from a larger (T3/T4) turbo, which is probably about the same as 17 or more psi from your (and my) smaller turbo...so like klattr mentioned, it could be that it's just not flowing enough air to compensate for the rich fuel program. HOWEVER, a lot of people do get the 50 lb program to begin with (before upgrading their engine internals to hold a lot of boost), and only run around 10 psi with no problems and without having the tune being stiflingly rich.

Also, is your engine built? If so, what's the CR? What's the CR that the ECU was designed for? I believe the lower CR tunes have more aggressive timing...and could have more aggressive fuel maps as well. I can't confirm this though...Your injectors are also flowing a total of 100 more cc/min more than the program is designed for. I'm glad you posted this because I was considering using 550 cc side feeds to avoid the hassle of going to top-feed fuel injectors.

What's suprising is that even with the small T3 super 60, according to the dyno the power keeps climbing even to redline...thats good news for me, because I would expect the power to drop of quite a bit due to the boost falling at higher RPMS.

[Nismo_Freak]

Wow, that is super-rich...makes me nervous because I'll be running the same program with the same turbo, at least until I have the money to upgrade it (which will not be any time soon, my engine rebuild cost me $2100+ not including parts).

The thing with the JWT program is that with the 50 lb tune, most people are running like 15 psi from a larger (T3/T4) turbo, which is probably about the same as 17 or more psi from your (and my) smaller turbo...so like klattr mentioned, it could be that it's just not flowing enough air to compensate for the rich fuel program. HOWEVER, a lot of people do get the 50 lb program to begin with (before upgrading their engine internals to hold a lot of boost), and only run around 10 psi with no problems and without having the tune being stiflingly rich.

Also, is your engine built? If so, what's the CR? What's the CR that the ECU was designed for? I believe the lower CR tunes have more aggressive timing...and could have more aggressive fuel maps as well. I can't confirm this though...Your injectors are also flowing a total of 100 more cc/min more than the program is designed for. I'm glad you posted this because I was considering using 550 cc side feeds to avoid the hassle of going to top-feed fuel injectors.

What's suprising is that even with the small T3 super 60, according to the dyno the power keeps climbing even to redline...thats good news for me, because I would expect the power to drop of quite a bit due to the boost falling at higher RPMS.

Nothing short of an absolute error would cause the engine to run that rich.

Airflow is dictated by the MAF for tuning BTW. The ECU could care less what turbo is on the engine.

[fastpace]

Wow, that is super-rich...makes me nervous because I'll be running the same program with the same turbo, at least until I have the money to upgrade it (which will not be any time soon, my engine rebuild cost me $2100+ not including parts).

The thing with the JWT program is that with the 50 lb tune, most people are running like 15 psi from a larger (T3/T4) turbo, which is probably about the same as 17 or more psi from your (and my) smaller turbo...so like klattr mentioned, it could be that it's just not flowing enough air to compensate for the rich fuel program. HOWEVER, a lot of people do get the 50 lb program to begin with (before upgrading their engine internals to hold a lot of boost), and only run around 10 psi with no problems and without having the tune being stiflingly rich.

Also, is your engine built? If so, what's the CR? What's the CR that the ECU was designed for? I believe the lower CR tunes have more aggressive timing...and could have more aggressive fuel maps as well. I can't confirm this though...Your injectors are also flowing a total of 100 more cc/min more than the program is designed for. I'm glad you posted this because I was considering using 550 cc side feeds to avoid the hassle of going to top-feed fuel injectors.

What's suprising is that even with the small T3 super 60, according to the dyno the power keeps climbing even to redline...thats good news for me, because I would expect the power to drop of quite a bit due to the boost falling at higher RPMS.

The engine is stock with stock compression. I am going to call jwt tomorrow and see what they say about it. I will eventually send it off to get the proper tune.

[klattr1]

Airflow is dictated by the MAF for tuning BTW. The ECU could care less what turbo is on the engine.

lets say you run a T3 turbo on a JWT ecu which has a linear air fuel ratio range and then put on a T88 turbo. the air fuel ratios from about 2000 rpms to about 4000 rpms are going to be alot richer than before and the air fuel ratios from 5000 rpms to 7000 rpms are going to be alot leaner. same thing can happen with aftermarket camshaft changes as well.

thats why people like JWT and Enthalpy encourage custom dyno tuning according to setups or retunes due to parts changes that would greatly affect the characteristics of the powerband (airflow).

[Nismo_Freak]

lets say you run a T3 turbo on a JWT ecu which has a linear air fuel ratio range and then put on a T88 turbo. the air fuel ratios from about 2000 rpms to about 4000 rpms are going to be alot richer than before and the air fuel ratios from 5000 rpms to 7000 rpms are going to be alot leaner. same thing can happen with aftermarket camshaft changes as well.

thats why people like JWT and Enthalpy encourage custom dyno tuning according to setups or retunes due to parts changes that would greatly affect the characteristics of the powerband (airflow).

Nope.

MAF meters incoming air and registers a voltage. That voltage dictates the amt of fuel being injected.

Like I said the engine does not care about the size of the turbocharger... only the airflow passing through it.

JWT could care less what turbo you have.

[klattr1]

ok, then explain to me the difference of air fuel ratios between these two runs where all parameters were the same except switching from a standard t3/t04e to a laggier Precision SC61 (compare 310 rwhp run to 330 rwhp run>>exact same boost level).

you'll notice the difference in the bottom end especially (afr's off the charts). what does that mean? less airflow in bottom end from a laggier turbo. and yes, ive talked to JWT about this and they agree that different turbos might require retuning depending on how extreme of a change from the original program it is.

i'll put it in different terms for you which you might understand since you think the size of turbo doesnt affect the linearity or consistency of the air fuel ratios. try putting a GT25R on a stock ecu'ed SR20 without any fuel trimming with a SAFC. do you think the air fuel ratios are going to be exactly the same as they were before?

prolly not. thats why retuning would be necessary.

[Jeff240sx]

ok, then explain to me the difference of air fuel ratios between these two runs where all parameters were the same except switching from a standard t3/t04e to a laggier Precision SC61 (compare 310 rwhp run to 330 rwhp run>>exact same boost level).

you'll notice the difference in the bottom end especially (afr's off the charts). what does that mean? less airflow in bottom end from a laggier turbo. and yes, ive talked to JWT about this and they agree that different turbos might require retuning depending on how extreme of a change from the original program it is.

i'll put it in different terms for you which you might understand since you think the size of turbo doesnt affect the linearity or consistency of the air fuel ratios. try putting a GT25R on a stock ecu'ed SR20 without any fuel trimming with a SAFC. do you think the air fuel ratios are going to be exactly the same as they were before?

prolly not. thats why retuning would be necessary.

Ryan, I'm with the establishment (mod) on this one. The difference in air fuel ratio is soley dependant on the difference in power. Power is dependant on the ammount of air you cram in the cylinder. So, more air requires more fuel, but here fuel is a fixed variable. So more air changes the A:F ratio.A turbo in and of itself will not require a reprogramming or a change in A:F ratios. But making more power with that different turbo, even if it was the same boost levels, will.-Jeff

PS: Your first example of t3 vs. t88 is incorrect too, because the maf only cares about voltage. The ecu only cares about the maf signal. The turbo, when the t88 sucks in more air, does so through the maf, and the ecu compensates. In your scenario, you suggest that going to a giant turbo from a small turbo, while making the same power, will cause you to run rich and blow a motor. That doesn't happen, ever.

[nissanfanatic]

Actually, AF ratios would be the same on that SR you were speaking of klattr1. They would be the exact same given the ECU was recieving the exact same load signa. And that would thus lead to a lower boost pressure for the same airflow. Now retuning would def be a plus because the turbo may flow more air quicker(spool quicker) or slower thus leading to areas of the fuel and/or timing map that weren't used before.

MAFS solely detects air flow. Nothing more.

[klattr1]

But making more power with that different turbo, even if it was the same boost levels, will.

this is what im talking about.

more power = more airflow

anytime you change a turbo and the flow characteristics are different enough, you will not have the exact same linear air fuel ratio that you had before.

[McAdam]

more power does = more airflow, but!!! something is seriously screwed with this dudes set up. technically, you should be able to run a JWT tune on an NA car and have it run decent, because the MAF measures the airflow and then the ECU injects the proper amount of fuel, dependant upon load, Throttle position and engine temperature.

changing turbos will not make an engine run lean or rich, unless you put a bigger turbo on it that flows too much air for the MAF to measure or outflows the injectors. going from a large turbo to a smaller turbo should NEVER cause a MAF metered motor to run rich.

McAdam

[turbo90]

i think Nismo_Feak said it first and right,"Something is very wrong."airflow is the same, wether it's coming from a hairdrier or a T88, if everything is right the turbo shouldn't matter on a MAFS car, MAP yes (same pressure more/less CFM). Maybe Jim Wolf flubbed, I remember reading a post a few months ago about someone who detonated, and blew an engine on a JWT tune. Everyone f*cks up now and then

[klattr1]

i understand this isnt the guy's problem. he already knows what his problem is, hence my post up top talking about him using 550cc injectors on a setup designed for 525cc injectors.

we just got off on a tangent. thats all, no biggie.

[Nismo_Freak]

ok, then explain to me the difference of air fuel ratios between these two runs where all parameters were the same except switching from a standard t3/t04e to a laggier Precision SC61 (compare 310 rwhp run to 330 rwhp run>>exact same boost level).

you'll notice the difference in the bottom end especially (afr's off the charts). what does that mean? less airflow in bottom end from a laggier turbo. and yes, ive talked to JWT about this and they agree that different turbos might require retuning depending on how extreme of a change from the original program it is.

i'll put it in different terms for you which you might understand since you think the size of turbo doesnt affect the linearity or consistency of the air fuel ratios. try putting a GT25R on a stock ecu'ed SR20 without any fuel trimming with a SAFC. do you think the air fuel ratios are going to be exactly the same as they were before?

prolly not. thats why retuning would be necessary.

Again you are incorrect.

Two different levels of airflow dictate two different fuel values. It ALSO dictates two different timing values. Timing affects the measured A/F ratio.

Turbocharger efficiency also plays a role, but all of these effects are minute in the grand scheme of things.

[Nismo_Freak]

i understand this isnt the guy's problem. he already knows what his problem is, hence my post up top talking about him using 550cc injectors on a setup designed for 525cc injectors.

we just got off on a tangent. thats all, no biggie.

25cc of injector flow does not cause that much enrichement.

The problem is greater.

[klattr1]

25cc of injector flow does not cause that much enrichement.

the base 50 lb/cobra mafs program runs rich in the first place (10:1 range) so running a bigger injector than what its intended to run will make it even more richer.

[klattr1]

Timing affects the measured A/F ratio.

wow, ok, now you have totally ruined your credibility in this argument.

[klattr1]

Actually, AF ratios would be the same on that SR you were speaking of klattr1. They would be the exact same given the ECU was recieving the exact same load signa.

so you are saying that putting a GT40R and running it at 7 psi would yield the exact same air fuel ratio that a car ecu's was originally designed to run at 7 psi on a tiny *** T25 turbo (flat line 12:1 for example and assuming neither mafs or injectors maxed out)?

[klattr1]

for all those that are reading this thread and believe that by putting in a JWT ecu, Enthalpy ecu or whoever decides to tune ecu in the next few years, that you can put whatever turbo on your car and the air fuel ratios will be the exact same as before, please dont believe it cuz you will yield different results.

the constant variable: boost

lets say you have a mafs system with T25 at 2.5v of airflow. then you have mafs system with a T70 at 2.5v of airflow.

what is gonna be different about these two? rpm at which its provided

fueling is applied according to mafs voltage (load) vs rpm so the fuel % value would be different for the given 2.5v of airflow.

and yes, JWT does dyno tune cars. they dont put Clark in his little room and expect him to guess or simulate what everyone is running. the dyno tune with certain turbos and expect the client/customer to use that or something very alike which wouldnt throw the air fuel ratios off base. so with that in mind, JWT didnt as well dyno tune their 50lb/cobra mafs program with a t3 turbo.
Modified by klattr1 at 1:53 AM 5/23/2005

[turbo90]

but fuel enrichment for 5000rpm and 2.5volts would not be greater than 3000rpm and 2.5volts? sorry, is the tps sensor accounted for in the EFI calculations?

[Jeff240sx]

525cc vs. 555cc is ~5%, so a 10:1 a/f 5% richer is 9.5:1. Then, it's tuned a bit richer due to the airflow in teh upper rpms for a t4 compressor that most KA-T owners run. I see Klattr's point here. Adding alot of small things that otherwise would not make much of a difference stack up. However, that's not ruling out the possibility of a flat out bad tune, or his fuel pump outflowing the FPR.My cobra/50# tune runs rich. I'm happy to get 250 miles out of a tank driving in the city. -Jeff

[klattr1]

absolutely Jeff. thanks for the lookout.

there are tons of variables that affect air fuel ratios. one of them being hardwiring walbros with 30A relay and thicker wire.

if you think its hard to examine why people are having problems with JWT ecu's on forums in general, imagine being in JWT's shoes. lol. its a tough game which they try to maintain but if i were them, i would have TONS of technical information on their website and/or provided with their ecu's but obviously nobody has taken the time to do so. i brought up the idea to them to make them understand (Jim and Clark spefically) that not everyone is up to par with them with tuning/forced induction concepts and the variables that affect it all. but of course that idea was shot down with "well, its not our fault" lol. im in the frame of mind where you have to play safe no matter what, kinda like "defensive driving" which I should practice. HAHA.

[turbo90]

im not trying to be an *ss, but i'm confusedI don't know everything, but I'm no slouch.my head hurts. does jwt anticipate what the cfm should be on their tunes?--for every rpm?klatter, im not a scab, i would really like to know why you are right, now i do not see why more mass=more volts=more fuel=more so //against rpm what ever; hit me up on AOL: tomsbeetle

[Nismo_Freak]

wow, ok, now you have totally ruined your credibility in this argument.

If you run very little timing you can effectively create alot of fouled mixture. The A/F can change as a result of what was burned and not burned. The mixture is not solely uniform.