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2G Hello, new to dsm tuning. Can you help tune my new ride?

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bizie

Proven Member
129
3
Jul 17, 2014
hagerstown, Maryland
Finally got my first boosted car. Good old 97 gst with the 16g turbo at 16psi, 272 cams, 550 injectors, safc2 tuner, walbro 250, or is that 255? I don't know but the guy told me 250. It has a full 3" exhaust from the turbo back, it does have a cat, and it does have the ARP head studs. It has a pro-comp ultra lite air fuel ratio meter and when I stomp the gas it's right before the rich zone and often flashes green. When I am just driving normal I barley see the fuel air meter move at all and is usually in the lean zone if it does come up. Does all of this sound normal? This car also has no power steering, the seller said removing it added 10hp, LOL, I almost lost it when I heard that. I mean I could understand maybe a 3hp gain but no way 10hp, LOL. I am a motorcycle mechanic and know very little about turbo cars, any help is much appreciated.

I got the car for $3900 and it was out of tune from the 4-5k rpm range, but only in 3rd and 4th gear. Car pulls hard in all gears until 4k rpm in 3rd or 4th and looses all power. The seller told me its just 3rd and 4th gear being short and I needed to shift, I told him he's lost his mind LOL, this guy...smh... I noticed my air fuel meter going very rich at the time of the power loss. So I started reading and reading about the safc2 tuner and tried to work out the tune. By trimming more fuel away in the 4-5k rpm zone (At -33% now) I was able to get the car to pull all the way through 3rd and 4th gear. For some reason now the tune issue has jumped into the 1st gear where it was not before. Its losing power at about the 3k rpm in first gear only but more so when the engine is cold. I have the tune so good for 3rd gear I am reluctant to mess with it anymore. Also, the 1st gear seems to pull hard once I've been driving for a while and every things nice and hot but when I first start the car pull out of my road I stomp first gear and lose power at 3k rpm. I'm not sure if this is normal for a supped up turbo car or not.

My safc2 Hithrottle settings are as follows, 1000rpm @ -12%, 1600@ -16, 2200 @ -20% 2800 @ -27%, 3400 @ -28%, 4000 @ -33%, 4600 @ -37%, 5200 @ -38%, 5800 @ -38%, 6400 @ -39%, 7000 @ -40, 7600 @ -43%. Do these numbers sound okay for the mods I have? It really seems to pull great for the most part.

I'm from Hagerstown MD and everywhere I call for a dyno tune turns me down when I say I use the safc2 tuner. I don't know why they would since ignorant old me can even make improvements but its still not perfect and I've been slamming 3rd gear around hear for the past two days straight. I really don't want to slam 1st around here since it peels wheels every time.

Can someone help me tune this thing with the equipment that is currently installed? Do I need to buy a fuel pressure regulator? A person I talked to said he has a 450hp eclipse with out one and it isn't 100% necessary. Does anyone know where I can get a dyno tune around here? I think I know where they get the name tuner cars... LOL all day tuning.
 
How does the average joe schmo do a boost leak test in his driveway or is that something for a shop to preform?

You absolutely can do this yourself. All you need is a boost-leak tester and an air compressor. If you don't have an air compressor, the gas station does...have you ever filled your tires with air? If you don't feel like building your own tester, I highly recommend siliconeintake's leak testers. For a 16g you'll need a 2.25". After years of having crappy testers pop off (including ones I have made), these are the only ones that have fit the bill for me.

Its not as bad as you may think. I stayed away from speed density for years thinking it was a pain when I finally switched over I slapped myself for not doing the switch earlier. LOL
Seriously. With Link, it's pretty damn easy...almost "plug-and-play" easy. Oh yeah, and don't forget the best reason to go speed density - LINK TOOLS
 
You absolutely can do this yourself. All you need is a boost-leak tester and an air compressor. If you don't have an air compressor, the gas station does...have you ever filled your tires with air? If you don't feel like building your own tester, I highly recommend siliconeintake's leak testers. For a 16g you'll need a 2.25". After years of having crappy testers pop off (including ones I have made), these are the only ones that have fit the bill for me.


Seriously. With Link, it's pretty damn easy...almost "plug-and-play" easy. Oh yeah, and don't forget the best reason to go speed density - LINK TOOLS
once you get it set up and ready to tune its plug and play easy!
 
The local guy I talked to with a eclipse said that the 16g turbo is capable of 25psi. So do you guys think I would be safe to turn the boost up to 25 or would it over stress my internals? I am currently running 16psi.
 
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I also wanted to add that by correctly hooking up my intake and waste gate vent tubes I has to lean the fuel way out. I just wanted to add that in case someone saw my safc2 numbers, they were way too low. They max out now is at -28%. Before they maxed out at -43%. I was wondering what was going on when I had to lean it out 43%.
 
I ran the factory regulator for years with a rewired 255 and noticed absolutely no difference when switching over to an adjustable regulator...IMO it's not necessary.
A adjustable fuel pressure regulator is not always mandatory, people who scream afpr afpr generally have never made more than 250whp...I ran 11s on a 60mm turbo, 35psi, big injectors and pump with a Stock 2G regulator. The best thing you can do is general maintenance, boost leak test, ditch the afc asap.

I am also running a rewired 255 on a stock fpr. This is a myth that should have been busted a longgg time ago. The only drawback to this setup that I've noticed is that I dip into the 12.7-13.2 range between shifts (which is less than a couple seconds so it doesn't matter).
 
So do you guys think I would be safe to turn the boost up to 25 or would it over stress my internals?
Don't even think about it. Without a logger, you have no way to monitor knock, injector duty cycle, etc...

The problem with safc's is that the ECU thinks the airflow is much lower than it actually is. This essentially forces the ECU to reference a different area of the timing map, where pressure is lower and timing is higher. Too high of timing, with respect to cylinder pressure and you increase the potential for knock. If you can't monitor what's going on, then you're playing with fire (no pun intended) and you'll have no one else to blame but yourself when shit hits the fan. Remember when I suggested that you get a real tuning solution? This is why. With an safc you have no direct control over timing.
 
I have got another issue, well I think. Today I went racing my friend in his nova and I noticed that close to the red line my boost would spike to over 25psi. I haven't touched my boost, I thought it was set at 16psi. Again, I just bought the car so bear with my ignorance. What could cause the boost spike? Is this because of the cracked valve cover? I do notice after I have a few strong pulls the oil is on the hood, indicating that it is shooting out of the crack. Could this cause the boost to go over the set point? Is the boost just raising because it's tuned better? I don't think I've ever paid attention to the boost gauge when I'm near the redline, its hard enough to watch the road, my air fuel, and my rpm to see where to make adjustments. Could the spring that controls the boost fail or self adjust while driving? Could this just be where my boost has always been at the red line and I haven't noticed before?

Btw I walked the nova by a car in every gear. It was a 350 with cams, carb jetted, and full 3" exhaust. I had a blast.
 
Simple math, because nobody else brought this up. The percentage differance between the stock 450 injectors and the 550's is only around 18% that means your baseline tune should be around that. most people start around 18% when they swap in evo 560s and go from there, and evo injectors run somewhere closer to 580cc.

Sounds like you need to read up a bit more on how to use the safc, roadrace engineering had a great article about the safc on a dsm platform.

To me it seems like you are having knock issues since your corrections are about double what they should be.

Also, as stated above a couple times, recirc that bov and do a blt.

Oh yeah, and get a wideband AT LEAST. My logger died on ke but I was still able to tune with no knock with just my wideband and a lot of trial and error. Dont turn up the boost until you understand how your components work... for what its worth, listen to these guys, ill be ditching my safc for link come fall. Its a crap platform that's about 15 years out of date. It is what it is, it works, you can get it to work.... but since you already have boost envy issues (wanting to crank it to 25 psi) I suggest a real tuner.

http://www.roadraceengineering.com/newafc.htm
http://www.roadraceengineering.com/newafcsetting.htm

Here ya go
 
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Correction on that over 25psi surges, it was 20. So I may currently be hitting 20 or 22 at the redline. Funny you say 18% because I did some more driving today and brought the fuel to -19% at the most trimmed and that is when the turbo started going to 20+psi, I almost thought I messed something up. I definitely will be getting a wideband. I will have to wait for the link, they are a little out of my current budget.
 
Just remember, if you go about this blindly it will cost you about 3-5 times what link costs. Just sayin.

Also, with your tune I noticed you kept making it leaner and leaner to redline. When boost hits you should be going rich again. If you look at the pages I put up and readthem/understand them, then you'll see in the included tunes they threw out there this exact pattern. You want your fuel mixture to be stoich when cruising and on light throttle. Then when the boost hits (around your 4k mark) the tune should level off and then go BACK on the rich side as rpm and boost increases. If you had a wideband you'd be able to see what I'm talking about.

For example, my high throttle (for evo 560's, more like 580's) is corrected about 24% at 3k and 4k, then at 5, 6 and 7k each point gets 2% richer. I hold 11.1 afr from 4k to redline with no knock.
 
You're saying I should be getting more fuel as the rpm increases. When I got the car the graph got leaner and leaner as the rpm increased so I figured I would do the same; so what you're saying is that it should be going richer and richer on the safc2 graph and not leaner? I know when I'm floored the air/fuel meter does just touch the rich. I read about the pro comp meter today and adjusted it to just that stoich at cruise and just touching rich when floored. This is where I get the most pull. My percents start at around +3 @ 1k rpm and -19% at redline. When I trimmed any less it would go too rich and lose power. With my current trims I can hold it floored from almost stalled and hold it to the redline with the meter just touching the rich zone, too far into the rich zone and I lose power and get a miss or is this the knock you're talking about? When I lean it out too much the car just doesn't pull as hard.

The safc2 tuner does have a spot that says KNK. Does this refer to the knock? It seems to stay at zero. I will double check tonight.

When you say 24% at 3k is that +24%?

I thought since the safc2 tuner is a piggy back unit that and the larger openings would naturally want to flow more fuel that you would then lean it out, correct? If you're at +24% at 3k I would think you would be too rich.

You have the 16g with the cams, pump, injectors and 3" full exhaust also? I thought I was doing this as the safc2 directions stated, I thought they said if you have cams or injectors you would need to lean or trim fuel to make it run right.
 
When you tune for wot you tune for an afr of around 10.7-11.2. This is rich, on the opposite side of the spectrum, say cruising, tune for 14.7 or you can even go a little leaner to save gas.

Yes, the corrections are negative, just like yours.

It really sounds like you need to get some 450's for cheap for the time being, zero the safc out and learn about tuning, buy a wideband and logger in the mean time. I mean you're talking about huge fuel trim changes from post # 1 to now.

Its all in math, you should have a steady curve close to -18%. The cams will make a small difference, but not a difference of -18% compared to -43% that you said your redline was at. Get the proper tools and monitors you need and don't worry about making 20 pounds of boost right now, or your buddies nova... cuz when your shits on a tow truck, his nova will definately be faster.

And yes, almost same mods as you. Bigger injectors, no cams, (have them but not installed)
 
That air fuel meter you keep referencing is just there to look cool and really gives you no info to tune with. You need a real wideband o2 meter that will give you useable data to tune from. Tuning off with green and red lights from that meter will end up screwing you up.
 
And, after going back and re reading this from start to now. The reason, or I should say... I feel like the reason you can't get a tune on this car, is because it probably has major boost leak issues somewhere. Test it! You cannot tune the car with boost leaks, your numbers will be all over the place because metered air is escaping, you tune for it, its still leaking, then you tune again, hey guess what? Still leaking. Even one single o ring failure that seems like nothing is a big deal.

I have been super busy the last couple weeks, my car failed emissions for running rich. I didn't tune it or screw with the safc like you have been doing. I had a local 4g63 shop look at and boost leak test it for $100. They found three leaks, biss screw, bov opening at 18 psi, and my boost controller had a leak. They got fixed correctly and I passed with flying colors. Like less that 1/4 of the readings they took from the car when the car failed. Boost leaks are a big deal.
 
Did you also read where my bov was left open and so was the vacuum on the back of the bov? That guy with that yellow wagon helped me get that and it seems to now be stable. I haven't really had to mess with my numbers too much after that. As soon as those got connected I had to tune it to the -19% zone. Before that I was -30's and up and still running rich. Now the turbo psi goes over to 20. I'm not worried about what the math says, I can tell when a car is running better or worse, I adjust accordingly.

I would love the wideband and dsmlink but I am currently out of spending money and need to have the car running right on the equipment I have.

I'm still going to do a boost leak test since I just got the ride but when you have a boost leak wouldn't you loose psi? Seems I gained it. I will do the test myself... Why would you ever have a shop work on your car? LOL, sorry, but I'm suppose to take advice from the guy who takes his car to a shop? Not only for a diagnostics but also had them repair it...okay then.

Where's my wagon buddy? You keep replying the same things but you're not answering any of my questions. Like forever ago when I asked if the cracked valve cover would cause me to leak boost? Or what causes boost to spike? Or is it normal for the graph to gradually have more fuel trimmed as the rpm raises? I did some more research and found YES it is normal for these to be more trimmed as the rpm increase, I now see why you have not answered so many of my questions, you don't know, which is cool, but don't like you do if you don't.
 
That air fuel meter you keep referencing is just there to look cool and really gives you no info to tune with. You need a real wideband o2 meter that will give you useable data to tune from. Tuning off with green and red lights from that meter will end up screwing you up.

The red yellow and green lights are useful data to tune with and it is possible. More difficult yes, impossible no. Only impossible if the gauge just randomly flashed but it actually does sense air fuel ratio just not accurately so to say that it gives you no useful info is wrong.

The more people say I can't do something the more I want to do it. Tuning this car with its current mods is becoming one of those things.
 
The only work I have not done on my own car has been a clutch and a boost leak test, they all came at times where I don't have time to piss around with it.

Being a dick on the forum is how you don't get help.

Back on track, I have swapped on my turbo, manifold, injectors, wired the safc, fixed botched wiring, tuned, diagnosed, vacuum delete with a battery and fuse box relocation. I have cams, timing belt kit, wastegate, holset turbo, new intercooler, larger injectors sittin on my desk to install myself come the end of summer. So explain how I'm some guy who doesn't know what I'm talking about just because I don't have enough time in the day to take my car to the shop twice the three years I've owned it and worked on it. Get a clue.

Also, its all about the math, your fly by the seat of the pants is what makes dsms have a bad name. You obviously have it all figured out, at least enough to call out someone who's been around the last 3 years, as opposed to your first thread.

I'm trying to help you. But you can be a smart ass and figure out nobody will help you after that.

I have an safc, I'm trying to help you out with solid math numbers and how to actually use the thing to your advantage. Yes, you need a $149 wideband by innovate and to be 100% boost leak free to make it at least a viable option to not use a logger. Until then, boost leak test it, keep the boost low and get the right parts.

You'll find the better help comes from the people with the actual parts you ask about, I bet almost nobody other than me responding to your thread runs an safc... Just something to think about.

Welcome to the dsm community
 
Also, you are a motorcycle mechanic? If there weren't a few people like me, who genuinely don't have the time to work on their stuff, you wouldn't have a job.

Sucks having a family and no garage at the moment. But that all changes next month. Good luck with your car.



And just to bring some math into your own world of motorcycles, you have to measure clearances and tolerances all day long, what do you mean you don't care about math... you measure a valve clearance on a bike and its off, you use math to correct it. Why is tuning with injectors any different. The injectors are flowing the rate they are advertised as, you have to use math to calculate how much air to compensate around the injector. To say this is wrong is ignorant and that all you have to prove on here is a point.

People can't help if the words fall on deaf ears.
 
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Where's my wagon buddy? You keep replying the same things but you're not answering any of my questions. Like forever ago when I asked if the cracked valve cover would cause me to leak boost? Or what causes boost to spike? Or is it normal for the graph to gradually have more fuel trimmed as the rpm raises? I did some more research and found YES it is normal for these to be more trimmed as the rpm increase, I now see why you have not answered so many of my questions, you don't know, which is cool, but don't like you do if you don't.

Part one, no. The crack in the valve cover will not cause a boost leak, the reason the oil shoots out is because of crankcase pressure. The valve cover does NOT hold boost pressures. Assuming you have the lines properly hooked up from pcv to intake manifold, and the left side of the valve cover to the intake. This will vent your pressures if hooked up right, and hopefully stop the spraying of oil all over, it will just puddle up around the plugs.

Part two, boost spike. It could be anything, if you do your own research on a few of these subjects you would find that most lead to a wastegate issue and large exhausts. The fix is porting the turbine housing and wastegate hole to ALMOST the size of the flapper (so it can still seat itself). This fixes the issue 90% of the time. Other possible issues, the wastegate isn't opening all the way. Boost spike issues are wastegate related. Do you have an mbc hooked up? If that leaks it will leak off pressure to the wastegate and not allow it to open correctly. Doing a boost leak test would find this out, weird huh.

Part 3. Boost leaks will make your ecu dump more fuel in the cylinders. Let me say that again. Boost leaks will make your ecu dump more fuel in the cylinders. Enough on that.

Part 4 I didn't answer your "questions" because simple engine knowledge should answer them for you. Does a valve cover on a bike see compression from the pistons, nope, it just covers the valves. Just like with a car. If its broke, fix it, I have 4 valve cover laying around painted and ready to go, because they will just crack looking at it wrong. Prep yourself, buy two if you plan on doing any real work to the car, you will break another one.

Part 5, what "graph" are you talking about? The one on the safc? Please, don't make me laugh anymore. Thats as useful as tuning with a boost leak. ( hint: that means it doesn't work well and you shouldn't rely on it, at all)

Anything else I don't know that I can answer for you? You should probably take a step back, and realize in your first post you said "I know nothing about turbocharged cars". Here we are 18 posts later and your telling off the help. Good one.
 
Well there is a graph and it does have numbers so I was just trying to get a reference for my pretend graph and tune. I know there is normally no pressure in the valve cover, this I know. The fact is that there is oil shooting up to the hood so that is why I asked the question.

On valve clearances; yes numbers are important. But math? Most math in tuning a combustion engine is just a reference. This is why everyone's vehicle has to be tuned differently.

You were helpful though, so for that I thank you. However, you seem to be a condescending individual. I'm here to learn, just because I work on motorcycles does not mean I know anything about forced induction. I will check the crank case vent and make sure it is proper. I will post a engine pic of that if you wouldn't mind double checking it for me. The guy I bought the car had everything messed up and I don't know how anything is really suppose to be connected. Thank you for understanding and helping the handicapped.

Also just a little fyi, I too have a family, no garage and I do all my work in my driveway or dining room. I just changed a trans on my back in the driveway off jack stands. You sir are just as capable as I. I don't trust paying someone to work on my stuff because when they mess up I get livid, and we all mess up, we're only human. I've seen it 100 times; mechanics up selling a individual and then messing something else up while fixing another. It happens because they rush and they don't really care about your car, all they want is to get the hours the job pays in the least amount of time. If you have to return for another paid job, better for them. If you know so much about these things then I would think you would do your own work. Its not like you really need sleep, just work through the night drinking coffee like I ;-) Some nights I don't sleep, most is 5-6 hrs or less. This is what I have to do to have a family, run a business, and fix all my junk when it breaks. It sucks but I love it, does this make sense? To me its just life dog.

Thanks again for your help I may have been up too late last night, hence the attitude.
 
So you think it would be best for me to start out high throttle-19 at 1000rpm then add fuel when the turbo kicks in?

I re-read all of your links, I think thats what they were saying. Right now my wife has the car so I can't mess with it.

I saw a bunch of graphs on youtube that has the trim increasing as the rpm raised. I will try differently, do the boost leak test and get back to you with my results.

One question you did miss. Doesn't boost leak cause you to lose boost? I'm not losing boost. I can still do the test but its going to take me a couple hrs just to make and do it. So busy with bikes right now...
 
I fully understand what you are saying, I don't enjoy taking the car to the mechanic, but when you have to you have to. At least its a trustworthy individual who is a supporting member on here, has vendor support from many of the vendors on this site and does top notch work. the three years I've owned the car its been there twice, apartment life sucks, can't take out the trans in my covered parking spot. I've had my hands all over this car. Sometimes you just don't want to do it.

And I dont feel I was being condescending until your "I can't take advice from a guy who took his car to a shop" comment, when you yourself work in a shop. BUT, that's neither here nor there, I don't really care anymore. I just think its funny and ironic.

Now that that is out of the way...

A small boost leak will make you lose boost, but, not a lot. The turbo will over work itself to compensate for the lost air, and the ecu also sees the turbo working harder (to make up for the lost air) so it dumps fuel to account for the airflow, BUT it isnt "real airflow" making it into the motor, its being wasted into the air, thats why you see it as being rich. You have all this gas and not the correct amount of air making it in the cylinders. Lost air means it can effect the vac that goes to an mbc, then to a wastegate. So the wastegate doesn't open properly, making the turbo work harder to supply lost air, and also spike because the wastegate is only x amount open instead of full on open.

This type of leak would be something like a biss screw, throttle body seals, injector seals or even the mbc itself could have a leak, causing both issues (unlikely, but could happen)

A bad leak, like a torn coupler, bov opening under boost pressure, or even the turbo itself would result in boost loss. You will still build boost, but it won't be much, like 5-7 psi

In my own experience, I had a coupler decide to fail on me while driving, had a 1" blow out. I would spike boost at like 12 and drop to 7 tops. Car ran like crap as it was tuned to run 20psi. When you have a leak that bad you can hear how hard the turbo is overworking itself to try and keep up.

And as for the tuning thing, I really truly feel you have a boost leak issue. Playing with the safc won't do anything but frustrate you till they get fixed. Like I've said 3-4 times now, the math on injector difference is 18% (as per the rre article, for 550's, for whatever reason my own math says 22%) The safc works by calculating the fuel difference and compensating for it through tricking the airflow meters. You do this calculation as your baseline. Then, when you have a wideband as at least a way to monitor your afr (for real, not the blinky light) then you can account for your own mods and tweak the numbers to what works with your car. When you make adjustments make small ones and make sure you keep a "flow" to them... as in, keep them within a few percent of each other

Hope this helps
 
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That's an odd typo on that article, I used the 18% number based on the fact they posted it in the article. But doing my own math three different ways says its 22% so I appologize for referencing that number. Either way though, 18% just means you would be on the safer side of a tune, being on the rich end is better than the lean, to a degree, till you start getting rich knock.

You can check it yourself if you want
550 ÷ 450 = 1.222
1.222 x 100 = 122.2
122.2- 100 = 22.2%

Just to touch up on how this all works, and through my own tuning with this platform. My math, even through tweaking the tune up top and down low by a few percent, is still at the EXACT math percentage change when boost comes on. I said a few posts back my correction was -24% at 3k, 4k. Well, the math says the difference is 24%. It doesn't lie brother.

560 ÷ 450 = 1.2444
1.2444 x 100 = 124.44
124.44 - 100 = 24%

Sorry again the article had the wrong %, this is the right stuff right here ^
 
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