MardiGrasMax

iTrader: (14)

Run .027 is the latest

Welp as you can see a 12.3et was quite a feat with the power I have at least their is some good news. Its now clear why my trap speed was so low.

The other dynos shown are my SC w/2.62" pulley ~14psi and then SC + small nitrous shot.

Set up is 1st generation PFI kit w/crush bends in the Y pipe and up pipe. Turbo is Turbonetics T4 P-trim 60-1 w/ .58ar exhaust. Tial 38mm WG w/0.5bar spring. Full 3" all mandrel exhaust. JWT ECU programed for 516cc injectors and Z32maf. E-Manage only being used to roll back MAF voltage to compensate for the 740cc injectors that are actuall installed. Profec E-01 boost controller dialed in for 16.5psi 10% gain, start boost off. MEVI is working. AFR was low 10's at TQ peak and 11 above 5750rpm, it may be a bit fat, but not 100whp fat.

So WTF could be wrong...

Big question is why am I down power even at 2500rpm?

1) Crush bends in the Y and Up pipe? For sure an issue.
2) Too small exhaust AR, others with T3's make about the same power? Are T3 exhaust housings that much smaller?
3) WG spring too small for the boost setting? Others dont seem to have this issue, perhaps I am missing somthing playing with the Profec, the lag is crap! but look at 3900rpm you can see where the BC takes over. I ordered a 1bar spring so we shall see if the spool up gets better.
4) JWT timing cant be that bad, Brett had a dam good dyno with his JWT set up, Paul did OK too. Time to data log the timing, and actually using the e-manage to roll back the MAF voltage should increase timing advance, the J&S has been quiet.

Could the Redline Shock Proof Heavy gear oil be sucking some power?

My plan is to get the 1bar WG spring in and put my .81ar exhaust housing back on and give it another run. If I have time even change the crush bends to mandrel. Look at how power dies off in the upper RPMs, it has to be chocking. I think this is a combination of these four issues, once I get the first three sorted we'll see if the last one is really an issue.

Reinventing the wheel sure is fun

Boosted Maxima

Hey.. Let me get this straight.. Your making less power now than before? What did you change?
You said it's laging down low? That's a prity small exhaust housing to be not getting with the program!!!! I'm running a .67 and have no problem. 60series turbo. 3bolt flange.
Back step to where you were before and start over.
~Scott

I30tMikeD

iTrader: (8)

I agree that it is probably not just one thing.

In my humble opinion a significant part might be the JWT timing gauging by your EGT's that you have posted in the past. I need to find this thread that was on a SR board disecting a JWT tune.

DA-MAX

iTrader: (10)

could that be the issue there...too much conflict?? you have the JWT pulling timing while Emanage manipulation of MAF voltage actually leads to increasing of timing. no knock, but a wierd mix...I dunno could this be the reaosn JWT discourages "piggyback" usuage on top of their programming?

I30tMikeD

iTrader: (8)

Here is the thread I was talking about. Main change was the timing....that is a big power difference

http://forums.freshalloy.com/ubbthre...e#Post67841206

Bags

iTrader: (3)

VERY dumb question.. is this the best dyno run you had? Was the engine allowed enough time to cool?

That looks VERY low. Crush bends in the exhaust is ~20whp, so in the up and down pipe, ~20 whp seems possible.


Have you talked to turbonetics about your Turbine housing size? They were helpful with me in my turbo selection.

Jay loved the Profec gaim setting.. I THINK his was set @ ~80%.. not sure

JWT timing.. no real answer here.

Power drop off, you said the MEVI is working... Timing MAYBE... Again the turbine may be to small for the amount of boost. I'd try the biger turbine housing 1st. It's a free mod, with dynoing the only cost. And You don't need tuning, and I'd do several pulls starting @ 12 psi going up in 2 psi increments. That will show several things. If power continues to drop, for example, you could be pushin to much CFM through the MEVI. ( Just a random thought, example ONLY )

I wish I could help more. If there is anything I can do, just ask

turbo97SE

iTrader: (3)

mmm just as I thought .. if you recall when you did your 12.XX run, I made a comment about choking with the .58. It sure looks like that is happening. Dynoing now and previously, are you using the same wheels? That also makes a difference. If you plot an power vs vehicle speed graph, that would be more obvious. Larger diameter wheels and tyre combo will lower your power at a given rpm.

Your crush bent piping is one of the sources I am sure. We switched that on the 3rd or 4th kit that was ever produced.

All I can say is that you are a very good driver to have made low 12s on this power on a front drive hauling that much car. Be proud of that at least

...*edit* looking at your graph, are you sure the VI is working? I know you said it did. There have been a couple of times when I have been on the dyno and the VI never actually moved. Mine is a little intermittent for some reason.

Nealoc187

iTrader: (23)

I'm going to guess it's a combination of things including turbine A/R, timing retard, crush bend, boost control, etc.

Here are my thoughts as I read through your post.

My first thought was that a .58AR turbine T4 (it is a t4 right?) should be coming on harder at a lower RPM. Maybe that is choking things up, I tend to think it is. Next thing to try - test out the .81 AR turbine.

Second is your boost controller. You say the boost controller comes online at 3900rpm, well 3900rpm appears to be exactly where things get really weird on your graph. I doubt it is a coincidence. Next thing to try - pull the boost controller out of the equation and do a run just using the wastegate spring, either the .5bar spring you have in now if you want to test it out right away, or with the 1.0bar spring you ordered.

Third is timing. I don't know enough about how the JWT and Emanage interact to know if this is feasible or not, but what about the idea of removing the JWT and just using a stock ECU? Obviously since the JWT is programmed for larger injectors (516) and the emanage is compensating even more for even larger injectors (720) you'd probably have to make a new map on emanage, but if that is not toooo awful hard to do it might answer questions about whether or not the JWT is pulling so much timing as to really be killing your power. And you've got J&S there to save your behind so that the timing doesn't get too out of hand.

Fourth is the crush bends. Solution for those is obvious.

Fifth is MEVI. This is sortof a secondary thing and wouldn't be my primary concern at this point, but to me that doesn't look like the graph of a car with a properly working VI. Just the overall shape of it, especially the sharp downturn it takes at 5600rpm. How have you tested its operation? Neutral throttle blips or have you tested it on the road with load on the engine such that you are ABSOLUTELY positive it is opening under load. Many people have had problems with the MEVI opening just fine while testing in neutral in their driveway, but once under load, not opening for lack of vacuum.

96sleeper

iTrader: (4)

+1 for pulled timing somehow, thats what it looks like to me based on the curve. Also like Neal said, that housing should be spooling quick. If it were just the housing choking your top end, you would think your bottom end spool would be crazy, especially better than a S/C taking power to turn. It definately looks to be in the timing/tune.

Boosted Maxima

Seems to be too many things controlling functions and they are conflicting one another. I'm confused on what's controlling what just reading this thread! I feel sorry for the ECU! See how that .81 housing does but I'm guessing it's going to be a bit less responcive until you get the timing resolved. That .5 housing should be almost instant power!
Let us know what you find!
Scott~

MardiGrasMax

iTrader: (14)

Well with regards to the several layers of control. Remember that the JWT is not pulling timing, it is has an actual programed ecu map. The only thing that is interfearing is the E-Manage lowering the MAF voltage to compensate for the larger injectors. The only thing this will do is make the ECU function on a lower load point, which will advance timing, AFR is the same. The E-Manage is not manipulating anything. While their is more potential for a loose wire to cause an issue I dont see this multi layer approach as an isue, of course stand alone or ROM flash would be prefered. The issue could be timing... I sent the guy on the SR board an -mail to see if he can do anything in a 95 Maxima ECU, he alluded to being able to reprogram JWT ECU's!

I did a run with the MEVI ziptied open and it looks the same up top.

Tire and wheel combo has changed...
Was 225/50-16 on RX7 Rims
Now on 255/45-17 on SSR Comp's
Might be some of it.

1bar spring and .81 housing then re dyno!

Nealoc187

iTrader: (23)

I'm sure the ECUs he is doing are s13 and b13 OBD-I ECUs. Those are pretty easy to do I hear, I know two guys locally who can do them, and other guys on the internet who can do them (including two guys from the board here) but OBD-II ecus are out of their capabilities currently. The encoding or something is much more complicated they say.

subs1000w

did you have a jwt ecu when you were sc

if you go to www.turbomustangs.com alot of the guys over there in the 10's and 9's are using single T70's and T76's with .81A/R housings on there 351ci and 408ci V8's making 600 to 900whp so i would think that a .58A/R would be fine for a 181ci making 400 to 500whp

MardiGrasMax

iTrader: (14)

No JWT when SC.

Consider the HP not the CI, the HP still requires the same amount of air flow. I looked through that forum and it appeared that most at that level run less PSI and allot less RPM tham me. CFM is the key here not just CI. But I hear ya!

MardiGrasMax

iTrader: (14)

FWIW .81 turbine housing is back on and 1bar spring is in the WG. I wont be able to test drive until Tuesday at the earliest, BA HUMBUG!!!

Boosted Maxima

Let us know how that go's with the different spring and housing. I'm running a .67 housing on a 60series and I've got full boost at 2400. It hits hard and fast. Boost does not creep. My Down Pipe is not good enough right now. I need to fabricate a 3" to the 2.5 Exhaust. That first section is the most critical. I'll also make a front fender dump at the same time.
I see what you mean with e-manage now. Why couldn't JWT program for the injectors? Or were the injectors after the purchase of the ecu? They'd proably charge you a bunch again to program it huh..
Let us know Tuesday!
~Scott

mad-max98

iTrader: (2)

hey scott you said you get full boost by 2400 rpm ,, how much is that and when does it start droping off and have you tried going on the track yet thnx dude

superdave2

My 2cents...
I have seen some weird problems when mixing emanage and ROM tuning. ROM tunes with SAFC work fine but ROM tunes with emanage just don't mix.

I know you aren't using the timing function of the emanage, but do you have the ignition harness installed?

Bags

iTrader: (3)

it's tuesday

MardiGrasMax

iTrader: (14)

I drove her into work this morning and data logged a few things. Boot onset is just a few hundred rpm slower with the .81 housing. At the point where the boost controller would take over from the WG spring, about 5.5pi, I have gained 1.5-2.5psi of boost. I get about 13.3-13.9 psi in the manifold out of just the 1bar WG spring. What looks good to me it the MAF voltage in the upper RPM. At ~7k with the old .58 housing at 16.6psi I was geting 4.85v on the Z32maf, now I got 4.84 at 13.9psi with the new .81 housingat the same RPM. That indicats that things are flowing better up top. I was looking a the up pipe and I do indeed feel I should replace some of the piping, their is a 2.5" pipe that is crush bent and for sure is 2.25" or less now. So I'll fix that next and see if it helps more. I will also dance the boost controller back up to 16.5psi and check the MAF voltage. FWIW I do recall having higher MAF voltages with .81 housing on, so I bet thats 50% of the issue solved.

Nealoc187

iTrader: (23)

Just curious when was boost onset with the .58 and when is it now with the .81

MardiGrasMax

iTrader: (14)

Here is the datalog for the runs with the .58ar and .4bar spring.
http://forums.maxima.org/showthread.php?t=349664

I just went to read the data log from my ride home and accidently erased it Oh well its another excuse to drive it tomorrow! But I was looking it over and I recal hitting 16.1psi at 4780rpm!!! With the old set up it took till 5620rpm to hit that same PSI. This should be a major improvement in the power band!

Bags

iTrader: (3)

good to know things are looking better and you know what is holding you back

MardiGrasMax

iTrader: (14)

1psi at 3190rpm
5psi at 3950rpm
7.4psi @ 4230rpm
9.9psi @ 4470rpm
12.4psi @ 4600rpm
15.5psi @ 4780rpm

Nealoc187

iTrader: (23)

What gear is this new info from?

MardiGrasMax

iTrader: (14)

3rd for both

JAY25

iTrader: (38)

The .81 AR flows better up top. Makes complete sense. You going to take it to the track in Feb to see how it performs? I sent you two emails. Dont know if you got them or not since the holidays just ended.