550s too small for my EVO3?

[92 AWD ECLIPSE]

Ok like the title says, are 550s not what most people use with a EVO3B16G? Here is why I am asking. I logged a pull on link the other day for the first time with link being installed, and at only 15psi, my injector duty cycles were at 96%. I logged another pull, and it jumped to 102%.
Relevant mods: EVO3, 255 rewired, FTS AFPR(baseline@ 43psi), 2gmaf, DSMlink, RC 550s

Are there any other factors, besides shortage of fuel, that would cause me to have such high duty cycles? Thanks for any help.

Rob

 

[G9S1X]

I think Im in the same boat. 17psi on big16g with 550cc injectors, 3k rpms - 6k rpms Im running a nice 10.2:1 - 10.6:1 a/f ratio. But after 6krpms she starts creeping to 12:1
Even addaing 4% on the safc @ 6k+ rpms it doesnt help much. However Im at 37psi base fuel pressure. Tonight Im going to crank it up to 40psi or so and see how much more I can squeeze out of these 550's before I go bigger.

Someone once told me 17psi on 550cc is pushing it. But Im sure people have done more with 550ccs, just have to wait untill one of them post

 

[tom04841]

two words......Water Injection

That will help you out with your idc's. Plus the average kit can be had for cheaper than a set of new injectors.

 

[G9S1X]

I know it has worked for others, but Im not a big fan of water injection Going with the 750cc's and being done with that and I recommend 92 AWD ECLIPSE to do the same.

 

[92 AWD ECLIPSE]

Yah, I think I am leaning towards PTE780s myself. I have my baseline set at 44psi, but I am not really getting a shortage of fuel. I hit max power at 6k, and it drops off from there, but my air fuel is at 9.8:1-10.5:1, so its theoretically running a little rich. I have no knock either, but I definitely plan on running more than 15psi, so I think an injector upgrade would be wise.

 

[dsm-onster]

The evo3 at 15psi puts no more air into your engine than a 14b at 15psi. There is a boost leak or there is a maf problem. You can get away w/ 20 psi and 550s. The only time you need more is w/ cams bore/stroke increase, over 25 psi; things that increase flow. Just because it is bigger turbo does not mean that it puts more air in your engine at the same psi as a smaller one.

 

[dsm-onster]

I know it has worked for others, but Im not a big fan of water injection Going with the 750cc's and being done with that and I recommend 92 AWD ECLIPSE to do the same.

What happened? I ran my small 16g at 22psi on stock 450s and stock fuel pump and stock sidemount w/ pump gas for a year and had no problems.

Drowning your combustion chamber in gasoline is no match to transitional fueling such as water/alky injection.

 

[92 AWD ECLIPSE]

Yah, I am hoping it is an maf problem or boost leak, I just got an MAFt and GM maf, so I will be putting that in in a couple of days, along with replacing the TB shaft seals, after that we will see what happens.

 

[1993TalonTsiAWD]

The evo3 at 15psi puts no more air into your engine than a 14b at 15psi. There is a boost leak or there is a maf problem. You can get away w/ 20 psi and 550s. The only time you need more is w/ cams bore/stroke increase, over 25 psi; things that increase flow. Just because it is bigger turbo does not mean that it puts more air in your engine at the same psi as a smaller one.

How can you seriously have 3green blocks with info like this. You can't compare turbos by psi. Trust me the air flow will be different between the two both at 15psi. Thats why 15psi in a 60trim feels a lot better then 15psi in a 14b. The 60trim flows tons more than the 14b at that same psi level.

Derek

 

[andymoraitis]

How can you seriously have 3green blocks with info like this. You can't compare turbos by psi. Trust me the air flow will be different between the two both at 15psi. Thats why 15psi in a 60trim feels a lot better then 15psi in a 14b. The 60trim flows tons more than the 14b at that same psi level.

Derek

Derek,

First of all, we're not here to doubt other people's knowledge unless it's blatantly incorrect and this certainly isn't. Keep in mind, we're not comparing a 60 trim and a 14B, but an EVO III and a 14b. At 15psi there isn't much difference in airflow between both and a look at the compressor maps on both turbos will tell you this. While the EVO III will flow much more air than the 14B, it does so in higher boost ranges where the larger wheel really shines. At 15psi, there's minimal difference at best. Take it to 25psi and we're talking about something else entirely.

Andy

 

[kottyking]

What happened? I ran my small 16g at 22psi on stock 450s and stock fuel pump and stock sidemount w/ pump gas for a year and had no problems.

Drowning your combustion chamber in gasoline is no match to transitional fueling such as water/alky injection.

Are you kidding me? Why the hell would you run 22 psi on stock fuel system. Thats the dumbest thing i have ever heard.

 

[kottyking]

How can you seriously have 3green blocks with info like this. You can't compare turbos by psi. Trust me the air flow will be different between the two both at 15psi. Thats why 15psi in a 60trim feels a lot better then 15psi in a 14b. The 60trim flows tons more than the 14b at that same psi level.

Derek

I completly agree w/ you derek.

 

[andymoraitis]

Are you kidding me? Why the hell would you run 22 psi on stock fuel system. Thats the dumbest thing i have ever heard.

If the AFR and IDC's aren't out of control then it's actually s a pretty intelligent thing to do as you'll make max power. While I wouldn't recommend it to everyone, it's how we went fast before there were AFC's and other various tuning tools. How do you think people like Buschur, Shep and Switzer ran stock motor cars on the ragged edge and posted amazing times on small turbos?

I'm going to say this NOW and say it only once. The attitudes in this thread are going to stop or I'll start handing out negative rep in a wholesale fashion. Act like adults and I'll treat you that way. Start acting like 5 year olds and see what it gets you. If you can't disagree in an agreeable manner (i,e, supporting your theories without resorting to name calling) then don't disagree at all.

Enough already,

Andy

 

[DSM90AWD]

Assuming a relatively stock engine, you can see that the efficiency level of a 14B is actually greater than a large 16G at airflows that would equate to ~15psi at the intake. Stepping up the boost on the same engine, you can see that we even out at airflows ~20psi.

Now if you were to drastically increase engine VE (stroker, cams, intake) and take the engine to higher RPMs, the story would be much different and you'd see the larger turbo perform better at lower psi levels as the you'd be shifting those "dots" to the right in the below.

You must be logged in to view this image or video.

 

[DSM90AWD]

Ok like the title says, are 550s not what most people use with a EVO3B16G? Here is why I am asking. I logged a pull on link the other day for the first time with link being installed, and at only 15psi, my injector duty cycles were at 96%. I logged another pull, and it jumped to 102%

What are your AFRs? Are you fully tuned on the DSM-Link?

Alot of people try boosting the snot (more psi = more power right ) on their turbos on pump with the same factory timing and battle knock by drowning the cyls in fuel.

First thing is to make sure all the turbo's airflow is going into the engine by checking for boost leaks. Then set/tune for a less than maximum boost pressure, say 20psi on pump. Once you've got a decent AFR and little/no knock, turn the wick up a few more psi. The internal fuel/timing tables are airflow driven, so should adjust accordingly. That is until you cyl temps go up = knock, and then you can either retard timing, add fuel (lowering AFRs) or lower boost (AFRs should stay the same).

In my case I'd originally compensated for my small FMIC by running low AFRs (rich) and maxed my 550s out at 20psi on my 50-trim (around 330whp). Now that I have Kyle Tarrys extended trims/better ignition maps, I can run much leaner AFRs at the same boost levels

 

[dsm-onster]

you guys for chiming in... I am glad that i showed a little self-control and came back to this thread after I had cooled down. I feel like I would have stooped to these guys' level. Thanx for posting the examples and compressor maps to back up the knowledge. It would have been nice if I had posted some compressor maps and some links to prove my statement. It would have made a more rounded comment for those who don't understand.

Hopefully, they won't desregard the evidence for the sake of their passionate beliefs.

 

[LessIsMore]

If you havn't recently, try pressure testing the intake for leaks. I'd think 550's and 43psi base fp would take you a lot further than 15psi on that turbo.

I'm running a small 16g at 14psi and IDC peak at %101 at the top of third. Though this is on stock injectors and stock base fp.

Any input on how much of an impact a leak at the throttle body seals would have? This is the only boost leak I have left, though it seems significant. I'm hoping the high IDC are a result of a rich condition caused by intake leaks(throttle body seals).

 

[92 AWD ECLIPSE]

What are your AFRs? Are you fully tuned on the DSM-Link?

Here is a copy of the last run I was talking about. And no I am not fully tuned on DSMlink, I have an appointment in two days to actually have it tuned on a dyno, I was just trying to get a good base tune before hand.
Another thing to note: For some reason my BoostEst on link is way off. I am positive that I am boosting no more than 15 psi, a) I was watching my boost gauge b) I have my profec b warning cut at 17 psi,(for now), and the BoostEst is at 21 or higher. I dont know if this even makes a difference, but just wanted to let you know.

 

[dsm-onster]

What are your AFRs? Are you fully tuned on the DSM-Link?

Here is a copy of the last run I was talking about. And no I am not fully tuned on DSMlink, I have an appointment in two days to actually have it tuned on a dyno, I was just trying to get a good base tune before hand.
Another thing to note: For some reason my BoostEst on link is way off. I am positive that I am boosting no more than 15 psi, a) I was watching my boost gauge b) I have my profec b warning cut at 17 psi,(for now), and the BoostEst is at 21 or higher. I dont know if this even makes a difference, but just wanted to let you know.

BoostEst is a calculation that the ecu makes and then ships it the factory boost gage. A number that the ecu is receiving is off, way off. This is why we should never rely on the factory boost gage. I'm looking at your .dat file. Because the ecu thinks there's 23.7 psi peak boost, it is shooting your IDC through the roof. I would think that if you were really running 23 psi, then the ecu would need that much IDC w/ 550s w/ a stock rich tune... You also have your 4500-7500 fuel sliders set for richer than stock. This would also make your IDCs go through the roof. You have your A/F properties set correctly and this is confirmed by the target A/F ratio as it is showing around 9.5 at the higher revs.

First go back and set all your fuel sliders to zero. This should give you a little bit lower IDCs. If you want to take fuel away go negative on the sliders not positive.

1. Do you have a 2g maf in your 1G? becasue you have the 2g maf option active in your MAF compensation box.
2. Double and triple check w/ a boost leak test...

P.S. Why do you ahve your global compensation set at 30% for 550s?

[1 - (450cc/550cc)] * 100% = 18.18%

 

[1993TalonTsiAWD]

Assuming a relatively stock engine, you can see that the efficiency level of a 14B is actually greater than a large 16G at airflows that would equate to ~15psi at the intake. Stepping up the boost on the same engine, you can see that we even out at airflows ~20psi.

Now if you were to drastically increase engine VE (stoker, cams, intake) and take the engine to higher RPMs, the story would be much different and you'd see the larger turbo perform better at lower psi levels as the you'd be shifting those "dots" to the right in the below.

You must be logged in to view this image or video.

I stand corrected. I was wrong in every way on this issue. Learn something everyday. But the way dsm-onster said it could confuse people. Now that I look at it I see what he was trying to say. So sorry dsm-onster I once again stand corrected.

Derek

 

[dsm-onster]

I stand corrected. I was wrong in every way on this issue. Learn something everyday. But the way dsm-onster said it could confuse people. Now that I look at it I see what he was trying to say. So sorry dsm-onster I once again stand corrected.

Derek

No beef. Like I said. I looked back and see that my wording could definately confuse. I'm glad I bit my tongue. There's no need to have hard feelings between us when we're both here to help this guy. We both share the same affection for the same kind of car. It's all good. I learn here every time I log on .

 

[92 AWD ECLIPSE]

dsm-onster,
I will re-adjust my fuel settings, but what you're saying makes sense. I am replacing the TB shaft seals tomorrow, as well as the maf, so after that I will post new logs.
And yes, right now, I am running a 2g maf in my 1g, but I will be going to a GM with maft.

As far as global settings, the reason I have -30% is because I have my baseline set at 43, so my calculations were as follows:
43psi/37psi=1.162 450/550=0.8181 --> .8181/1.162= 0.705
--> .705-1= -.295*100 -->-29.5%

After I install the new maf and TB seals though I am going to set everything back to zero and go from there, because obviously my previous settings were not working well.

 

[DSM90AWD]

As far as global settings, the reason I have -30% is because I have my baseline set at 43, so my calculations were as follows:
43psi/37psi=1.162 450/550=0.8181 --> .8181/1.162= 0.705
--> .705-1= -.295*100 -->-29.5%

According to RCEngineering's Fuel Pressure Calculation:

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You'd need to subtract 24% Global Fuel

SQRT(37/43)*450 = 417cc = Stock Fuel
550cc = New Fuel

1-(417/550) = 24%

BTW.. I like happy endings

 

[92 AWD ECLIPSE]

Okay, I will try that setting too, I was just going off of the DSMlink manual, and the equations they used. Thanks for the input.

 

[kottyking]

If the AFR and IDC's aren't out of control then it's actually s a pretty intelligent thing to do as you'll make max power. While I wouldn't recommend it to everyone, it's how we went fast before there were AFC's and other various tuning tools. How do you think people like Buschur, Shep and Switzer ran stock motor cars on the ragged edge and posted amazing times on small turbos?

I'm going to say this NOW and say it only once. The attitudes in this thread are going to stop or I'll start handing out negative rep in a wholesale fashion. Act like adults and I'll treat you that way. Start acting like 5 year olds and see what it gets you. If you can't disagree in an agreeable manner (i,e, supporting your theories without resorting to name calling) then don't disagree at all.

Enough already,

Andy

Andy, I wasn't trying to flame or name call at all. It just concerns me that somebody is gonna think that all you need to do is get a boost controller and run ridicioulus amounts of boost w/ out taking in the fact of fuel cut, knock, timing retard etc. I guess I'll keep my mouth shut next time. Sorry to you and dsm-onster. I'm just trying to look out for fellow dsmers.