mcduck

Okay... two people have now said that 12.5 is rich for an N/A car and that 13.0-13.5 would be better. Should I send the ECU back to TS and have them lean out the range a little bit?

Also, the TS sight says they reset ignition timing throughout the RPM range. One would think this would take the timing question into account. However, when we first installed the cams & everything else, the idle was to low and the timing not quite right. Besides performance losses, the car tended to stall after quickly coming off a high rev. It is now doing this again a little... which is why we first thought timing may be the issue. However, I can see where this could be caused by A/F being too rich also. High revs... lotta gas flowing at an A/F too high... you back off quickly... there's too much gas for the air present... the car bogs down and stalls. That seems very reasonable to me.

I certainly hope its not the Borla headers. If they give me no gain, I can live with that, but if they are causing a loss I'd hate to have to pull them and put other headers on. They're just such a PITA to get to...

Thanksa again... gotta a flight to catch. I'll try to check in tonight.

Andy

Jim Jones

My set up is similar to yours, but I have a couple of things you don't. JWT flywheel for one.

I got 276.5 rwhp on the Dynojet, and I was disappointed with that.

How does your car FEEL on the butt dyno? That's what is really important anyway.

Eric1h

I have to agree with you. You have SIGNIFICANTLY increased the amount of air coming out, but not going in. I have seen this a 100 times, you open your exhaust up so much that you LOSE HP and Torque.(which why we all dont run a 6" exhaust) I would lose the cats and try again. The car needs a certain amount of backpressure to perform the way it should. i think your gains would be much higher if your exhaust were MORE restrictive, you may gain more high end with an open exhaust, but lose #'s everywhere else.

I mean, look at realistic #'s.....
Pulleys, these should easily give you 1-3HP at the LEAST
the cams should be good for 2-4, so that means everything Net'd you 3-4 HP.

Just rememeber, when mod'ing a car, the end result is the sum of ALL the parts, and some judt wont work with others.

if headers gain 4hp and a Borla TD gain 6hp, that doesnt mean that with both you'll net 10hp.
My guess, is that one or more mod may indeed be working against you instead of helping. Sucks to beleive it, but may indeed be true.
So, start with the process of elimination, remove the mods that are easiest and try again. Could be an expensive project to pull things off one at a time and Dyno after each, but think of the intellectual property you would hold afterwards.

Adding so many mods so quickly can realy be counterproductive, because you dont know what gains you got from each or where the weak link may be.

Morris

iTrader: (1)

Andy I think you should reset the ECU again. I know it is tough to do the throttle dance by yourself, so I would be glad to do the timing for you. Maybe after work one night this week.

Okay, let me add a few things to the comments.

I have the other Z that Andy refers to in his post. I dynoed right after Andy. This is the same dyno where I did my baseline (car was stock and peak hp was 239.9 hp). Yesterday, with borla TD and Crawford Hi-flow cats - peak hp of 238. So, I lost almost 2 hp.

Is there something wrong with the dyno? I would like to think so, but I don't. We had another car there that dynoed a few months ago on this dyno and he put down almost identical numbers again yesterday, with no mods made between dynos.

Eric1h

OK, PERFECT example...........I honestlythin Andy has opened up his exhaust TOO much. you lost hp with the Borla AND the cats, now, think about adding higher flow headers, you have released even more pressure. This could be negating some of the other mods that we KNOW produce HP..........Pulleys, cams, plenum

flynnibus

Well your stock numbers are right on for baseline.. so unless your car is really behaving differently due to 'learning' or environment.. I think the question of variation in the dyno itself isn't out of the question. We know exhaust and hi-flow are good for HP alone.. you're showing a net zero within error.

It is alot colder now.. which even with correction is a factor.

Not sure.. but even tho you want to stay with the same dyno due to variations.. sounds like this dyno is having its own variations.

zzzya

iTrader: (2)

Headers are a very critical piece and when you have a poorly designed set of headers on the car you can easily see problems and even a decrease in performance. Properly tuning your car is key with the mods you have. You may have to work on the timing issue and relay more information to TS so they can get your timing just right. Better yet, you may need to take the car to TS and have it done there. Cams + unequal length headers will make it more difficult to get it right. You were probably better off without the TS reflash because your mechanic had dialed in your timing and your A/F was probably running leaner. The TS reflash is definately a good thing if everything is tuned properly, but with your mods it becomes very complex to tune without having the car there. I would think that the reason your car was louder after the TS reflash is because TS fixed the issue with the throttle body not opening all the way. When you open the TB more, the louder it will get.

Here is some reading about headers and their design that may shed some light on the topic and the reason I chose Crawford headers:

http://www.headersbyed.com/bildbetr.htm

http://www.vetteguru.com/mods/headers/

Conceyted

iTrader: (7)

I did the same as what the speculation says here about opening the exhaust up too much. My last car, a 1998 eclipse gsx came stock with a 2.25 inch exhaust all the way back. I kept the stock turbo and opened up to a 3" full exhaust with no cat and a 3 inch downpipe. My times decreased, my power decreased, it was all down hill. But this is somehting you wouild feel thje minute you got your exhaust on. I am not sure this is the same situation.

rodH

iTrader: (2)

this means that there is only 2 possible answers, since you had a similar problem with less mods.

1. it is the Dyno (or conditions)
2. The exhaust is too open (is this consistant with what others have Dyno'd on different machines??) (this is one of the reasons that after I got test pipes I got a Plenum VS the Borla TD next, because I wanted to open up the exhaust and intake side, but it looks like McDuck did that)

mcduck

well, my flight was cancelled, so I'm back to monitoring my thread...

Richard/Jim... I go back to what I said earlier. The car is definitely feels stronger than when I had the Borla alone. My concern is whether it is as strong as it can be for given setup.

I don't think the flywheel would be that big a difference between your numbers and mine. Do have any figures prior to cats/headers? I know your previous dynos do not include the plenum, but what else did you add prior to this more recent run?

Eric1h...
I have heard and know that too little backpressure can be an issue. So, this may be part of the problem. It sure would be easy enough to test. The hiflow vs stock cats are an easy swap. So, we may look at that also. I don't agree with your estimate on the cams though. From what I know of cam dynamics, for how much NISMO cams exceed the stock cams, they should be putting out 10-15hp like is claimed. My bet is that the cams aren't adding in because of one of these other factors.

Also, if exhaust is beyond intake capacity, is there any other way I can increase intake flow (short of FI). This is why I think the CAI theory may be accurate. If the stock box flows better (or even the JWT), it would compensate for the too much exhaust issue.

Not an option... I'm on the opposite coast! That would be best if it were possible.

1. I don't think it is the dyno. As Morris stated, the M5 put down the same numbers that it did a few months ago with no mods done in between.
2. Exhaust too open? Adding that to my list of possible culprits.
3. I still think timing and/or A/F could be playing a part.
4. TechnoSquare mapping... another possibility, but I'm sure they'll work with us to try to make things right for my setup.

Keep the ideas coming. I have a list going and my guess is that Mark and I will come up with a battle plan to address each issue one at time someplace where we can dyno between changes.

mcduck

The Individual...

I could not reply to your PM and do not have AIM. Just email me at mcduck@earthlink.net

Wedge

I can certainly understand the frustration of planning and investing in relatively expensive mods only to have the dyno indicate a less than expected HP gain.

The dyno accuracy is under suspician by some. We have to ask: If the dyno is wrong, when was it wrong? On the runs following the mods or on the runs with just the Borla? 244.8 rwhp is higher than most with just the Borla. Was the baseline really lower than this? Morris states that with the Borla AND Hi flow cats, his highest pull was 238 rwhp. This is almost 7 HP less than your Borla only numbers and almost 2 HP less than Morris had with no mods. This is suspicious.

Usually, each dyno run gets better as the car heats up and things loosen up a bit. If you were running rich, could your plugs have gotten a bit fouled? Did anyone check the plugs following the dyno runs? As you know, they can give you a clue as to whether you are running overly rich or lean.

The reflash has been mentioned as a possible cause. What if the reflash is doing its job properly but the things it is controlling are not? Sometimes the simplest things are overlooked. (such as the quality of the gas you are using as was mentioned earlier)

I think the mods you have have the potential to give you the gains you expect. There is just some investigation and tweaking that needs to be done (possibly to things that have not been modified) to have these gains show up on the dyno.

I recommend that you try a different dyno and perhaps have Morris go along to dyno his car at the same time. The two of you can then compare notes on the old dyno and new dyno runs.

Good luck McDuck.....I have a feeling it will all come out just fine for you in a relatively short time.

mcduck

Since I'm not actually on a flight right now, I did some research and part of that was reading the So. Cal dyno day threads. I found this bit from Jeff@performance Nissan.

From what I found, he went from 249hp to either 265.2 on that dyno day (and actually had a higher reading of 268 on another dyno). So, just by adding hiflow cats and Nismo exhaust (to a car already with CAI, Cams, & headers), he picked up 16-19rwhp

Now, granted I added Crawford hiflows instead of Random Techs and borla instead of Nismo parts for headers and exhaust. However, the Borla exhaust added more power than the Nismo exhaust did in SportZ Magazine's exhaust shoot out. If the Crawford cats & borla headers are less, we should be pretty close to a wash on total numbers for the three components. All totalled, Jeff tallied up a 36hp gain over pure stock prior to flywheel changes.

If we applied that change to my car from my baseline (no mod) number of 227rwhp, then I should be at approximately 263rwhp PLUS whatever the Crawford Plenum and UR Pulleys give me. Even if that is only a couple horsepower, I should at least be around 265rwhp... even if the exhaust is too free-flowing.

No, but this is on the list of things to check.

I agree... which is why I'm hear picking the collective brain of the my350z.com forum!

Good idea... if not Morris, I can probably get Wayne to bring out his Mach1 again. That way, if we are on a different dyno, we can measure any change in HP on their control call (vs the original dyno) and use that to measure how much mine changes when we start tweaking things. Hell.... that's an awesome idea!

flynnibus

Everyone wants to beat on the timing horse.. honestly I think thats just bandwagoning based on all the timing talk around Vortech having it.. and ATI not in their kits. Your case is completely different. If anything, the timing concern should only be about whats the proper setup given your cams.. and since TS has done other nismo cam cars.. I would hope that portion would be correct. If anything, the only thing that would be going on is ultra conservative timing leading to low numbers.. but if you can find a datalogger, you could look at that.

I'd start at the basics.. look at how the engine is running.. check your plugs.. check your airflow.. then play from there. You don't have a really odd combination of parts so its not like you are off in left field. I'd swap a stock ECU if I could (wonder if you can get by the key transmitter by just having the key by your ignition...).. reset.. and start experimenting there.

350Z_Redline

iTrader: (1)

That's exactly why I take my car to the drag strip. I keep a spreadsheet of all of my runs and can tell which parts added X MPH to the traps. Dynos are good for tuning but not much else. I've yet to see a dyno sheet posted on this board that hasn't been challenged by either the car's owner or other members. If your Z can truly keep up with a Mach1 you have gained a lot more than ~9HP. I have no idea what my RWHP or RWTQ is but I know they have been increased based on my traps (4.24 MPH gain). My ETs have improved as well (.66 sec gain) but other factors could be at play there. Good luck with finding the issues (Car/Dyno) if any do truly exist. I hope you guys stop getting your feelings hurt by "low" dyno numbers and just enjoy your sweet rides .

Z1 Performance

iTrader: (564)

Yeah, if you want the car to self destruct on pump gas. your A/F target is right on, I would not necessarily mess with it's numbers. Your best bet is to try and get a stock 350Z on the dyno, and start by mimicing its timing and A/F tables. Again I am talking about the A/F under load, not while cruising or idling. From there, you'll be able to better figure out where your changes need to be.

I'd start with the one variable you have had no control over (in terms of tuning) so far......the ecu. If its not working correctly, then all the mods in the world won't work. Perhaps you can have TS speak with the guys at tomei to figure out where the ercu mapping should be.

You also need to be doing these pulls with at least an OBD2 logger to see if timing is being pulled anywhere in the rev range via the knock sensor.

I am having mine dynoed agan this wek, so I can post mine up for a comparison.

flynnibus

What?? Then I guess every stock Z out there is a timebomb huh?

He doesn't need to be running rich for the extra cooling... and he's not running FI. Stock A/F is 13-14 depending on where you are in the band. Hes not running any mods that would suggest he needs to richen to be safe.. he's only running mods that require higher fuel delivery to match his higher air flow.

Also.. if you do a search for other dynos.. you'll find stock cars with headers and exhaust still doing 12.5-14 through the entire range.

Still below stioch is perfectly safe for N/A.. at stioch is best for cat efficency.. the best A/F for our engine for output isn't really clear. The 'norm' for F/I applications is in the 11.5-12 range.. they need the extra cooling the fuel delivers.

I do agree with the knock sensor tho.. he could be sending the car into limp mode unexpectedly.

Eric1h

Andy, i agree that the cams SHOULD add more than my estimates, just going on the low side for pure conversation, and to state that something is def wrong. And remember that someone with Borla headers and Nismo exhaust may very well get better(or worse gains) than someone with borla everything. Not all exhaust parts are created equal. Not to say that the Borla is a bad exhaust, but the exhaust was designed to be a replacement for a STOCK exhaust system when it was designed.(maybe combined with the headers) but the headers came out some time after the exhaust, which again, was im sure designed as a stand alone product.

Also, make sure you dont have any vaccum hoses loose, AND...... when i spoke to morris friday night, I tried to make sur ehe knew that your car had to be WARMED UP before dynoing. Dynoing in the winter time is a whole different beast than doing it in the summer, if the car is TOO cold, the O2 sensors and other parts of the car go into "warm up" closed loop mode, which means all TS tuning goes out the window.

Were you best run/s the last ones? maybe the car was to cold when you started and got better as the car warmed up?

Z1 Performance

iTrader: (564)

I mean no disrespect to you, but I spend my days and nights tuning cars for a living...I know what is safe and what is not. Sure, under crusie or idle conditions, stoich is safe. If you think for a minute that stoich is safe under WOT, then I wish you luck on your tuning ventures...it is far from safe, and far from ideal for anything more than gas mileage. Having extensively datalogged my own car, I can tell you that A/F's are in the mid 12's by and large in WOT conditions. I dont much care what its doing at other times, so I have not logged cruise or idle conditions.

He has made changes to when his valves not only open and close, but how long they remain open for...that requires more fuel no matter how you slice it. Now, if that change is mild enough, the ecu might be able to provide the additional pulsewidth needed. However, his cams are a bit more agressive (IIRC than the NISMO's, which are said to not need any fuel changes at all). He has had to send his ecu back for reflashes a couple times already IIRC, so that tells me the ecu itself cannot cope with the cams in their raw state.

If the knock sensor is indeed kicking back timing, its because of what I metniond before...your A/F can be spot on and yet still knocking. Until he logs the car and has the person who can flash the ecu there with him, its going to be a neverending guessing game.

flynnibus

Its the other way.. the car runs in 'open loop' mode (no input) when cold. Once its come up to operating temp.. the ECU starts listening to the o2 sensors to tries to adapt for o2 levels in the exhaust.. and adjusts fuel to try to return to its 'ideal' level.

Also tho, others have said (including ATI) that the car goes into open loop mode under WOT (other cars do as well.. not uncommon). Of course on a dyno pull you are only at WOT. So you are only relying on timing and fuel maps.. no adaptive learning during those pulls.