Consequences of turbo > FMIC > injectors upgrade path with other mods done?

[Rice Over Wheat]

Ok, I'm considering purchasing the following turbo from Dejon Tools:

Model 5031E Often called the 50trim - Max Rated HP: 450
This turbo is very popular because it works well on the street with a stock engine at low cost.
Compressor wheel dia. 54mm - 50 trim / Spool-Up 3500rpm on 2 liter
Oil cooled center section with journal bearings and 360deg thrust bearing.
T31 Turbine wheel in a .63 A/R housing for good exhaust flow
Note: Flapper Door Models come with free Waste-gate actuator - select Mid or Hi range in accessories section

You can check my profile to see what the car currently has done. Note that I have a built a/t but additional drivetrain loss because of this. Other m/t's with same mods typically push approx. 270whp on the same boost. Last tune/dyno I was stuck at 242 whp 268 wtq @ 15 lbs. Dialing up to 18 resulting in zero gain. Dialing to 20 lbs resulted in losing hp, down to 220 whp. Garry Marsh at Speed Injected in Hallandale, FL., thought my T-28 is just too small to push more flow. Adding more fuel resulted in losing power. My SAFC actually is tuned to correct to less fuel (-5%) max for my peak power.

I asked whether the FMIC and injectors should be my next upgrade, thinking this would allow me to dial in more psi and more power on the T28. However he thought that the turbo was the primary bottleneck. Reading the turbo FAQ sticky and posts by the vendor, I'm inclined to agree.

Therefore my question is this...if I instead purchase and install the above turbo, but remain on the stock SMIC and 450 injectors, what would be the consequences and likely outcome vs the current setup with the T28? Would I make gains? I realize I will have mad heatsoak but let's hypothetically consider only a single run.

My target is a modest 300 whp right now. More later next year. I intend to upgrade to FMIC and injectors next, however I believe that the T28 is at its limit right now and they would not result in more power without the bigger turbo. Thoughts?

 

[DGajre777]

What is your power goal? Not your power goal now, what is your final power goal.

If you get the turbo before FMIC, injectors, fuel control, you will have to run it at a low psi. The gains you might make depends on what you run on your T28 now. I say get supporting mods before you get a bigger turbo.

I suggest the dual ball bearing wet version of that turbo, the 5031RE, it is a little more expensive but offers water cooling and spools up faster than the regular 5031E.

 

[v2ner]

Before reading this, consider what the above poster has said. Anyways, small turbos create more heat than bigger ones. Either way, a 50 isn't much of a jump from what you have now. The results will be pretty much the same. Now with a FMIC, your third will definitely pull more...but with too big of a FMIC, your 2G will be prone to overheating. There are ways around these problems though. Actually I'd say you should at least go to 560cc injectors.

 

[91-gsx]

dude...the t-28 is rated at something like 380hp. you only want 300hp, you actually have the perfect turbo for your current power goals. i will tell you why i think you lost more power with boost...knock. you are running a t-28 at 20psi trying to get more power out of it, and that is well and good because that is the turbos sweet spot or maybe even a few psi more. but you do not have the proper mods to do this. you need bigger injectors, you might be able to stick with the smic, but it is at its limits when it comes to 20psi+ runs because of heat soaking. let somebody else chime in on this one, but i am sure that this is the problem as i use to get knocking on my smaller 14b at 18psi because i was running out of fuel up top on the stock 450cc injectors.
later

 

[2gGSX]

For a 50 trim 550cc injectors are nowhere near big enough. He would need at least 650cc class injectors if not bigger if he'd prefer more headroom.

Edit: adding to respond to above post.

The stock SMIC is definitely not enough to push that turbo to its full potential (which by the way can get you to 300 whp). A FMIC may not be absolutely necessary, but in my opinion as well as others' you may as well. Beyond that and fuel mods your most effective modification for a big T28 will be the FP 17 psi actuator. Many people have problems with boost dropping off in the upper RPM range and this has been proven over and over to help immensely, with the average gain being about 3 lbs/min of airflow (from the DSMLink forums).

 

[v2ner]

For a 50 trim 550cc injectors are nowhere near big enough. He would need at least 650cc class injectors if not bigger if he'd prefer more headroom.

560cc are fine depending on what boost, octane, and fuel pressure he's goin to run. Keep in mind, I believe he's on an AFC. I wouldn't go past 20psi cause that's when 93 octane starts to detonate. Yes, i do agree with the 650ccs. I wouldn't go any bigger as they will flood upon WOT. That's why some people have to issue with the AFC where WOT doesn't feel as fast as 60%...or they will sputter.

 

[Rice Over Wheat]

What is your power goal? Not your power goal now, what is your final power goal.

If you get the turbo before FMIC, injectors, fuel control, you will have to run it at a low psi. The gains you might make depends on what you run on your T28 now. I say get supporting mods before you get a bigger turbo.

I suggest the dual ball bearing wet version of that turbo, the 5031RE, it is a little more expensive but offers water cooling and spools up faster than the regular 5031E.

I'm not certain I may reach beyond 300 whp at all and therefore do not want to sink too much $ into this car if that's the case. I'm considering moving to a V8, possibly a C5 next year on which I would like to add forced induction. However, I am also considering next year's WRX STi.

The guy who tuned my car is one of the leading gurus for DSMs in Florida, if not the entire southeast. He didn't think my 450s were at their limit yet as I actually had to lean it out in order to make gains. Adding more fuel made me lose power, which would imply I'm just not getting enough air flow to put the extra fuel to use right?

Now, Garry was surprised himself why I was only turning out 242 whp, even with a/t. He even questioned whether my turbo was really a T28. I haven't actually pulled the turbo myself and from what I hear from the engine bay its hard to tell the diff between the T25 and T28. The owner before me installed the T28. Is there a way to verify this without pulling the turbo? Serial # somewhere? It's a ported AGP T28.

Before reading this, consider what the above poster has said. Anyways, small turbos create more heat than bigger ones. Either way, a 50 isn't much of a jump from what you have now. The results will be pretty much the same. Now with a FMIC, your third will definitely pull more...but with too big of a FMIC, your 2G will be prone to overheating. There are ways around these problems though. Actually I'd say you should at least go to 560cc injectors.

Well I was considering the Dejon "Street" fmic, which appears to be a modest sized fmic. It's just that I wasn't certain whether a fmic would mostly just reduce heatsoak with my current setup.

For example, if I go with that fmic instead of a bigger turbo, can I really expect to make gains? I would consider this just to do the cold air intake mod to the old smic location.

Injectors are such a cheap mod I would probably do this with either the larger turbo or fmic, anyway. I guess the question is then: if you had my setup and could only buy either a fmic or larger turbo, which would you go with?

dude...the t-28 is rated at something like 380hp. you only want 300hp, you actually have the perfect turbo for your current power goals. i will tell you why i think you lost more power with boost...knock. you are running a t-28 at 20psi trying to get more power out of it, and that is well and good because that is the turbos sweet spot or maybe even a few psi more. but you do not have the proper mods to do this. you need bigger injectors, you might be able to stick with the smic, but it is at its limits when it comes to 20psi+ runs because of heat soaking. let somebody else chime in on this one, but i am sure that this is the problem as i use to get knocking on my smaller 14b at 18psi because i was running out of fuel up top on the stock 450cc injectors.
later

380 maybe on the "big" T28 that flows the same cfm as the 16G, but I have the regular T28. Also, again remember I'm on an a/t so that number's probably closer to 320. In any case, I'm still well short of where I should be. Thanks for the input.

The stock SMIC is definitely not enough to push that turbo to its full potential (which by the way can get you to 300 whp). A FMIC may not be absolutely necessary, but in my opinion as well as others' you may as well. Beyond that and fuel mods your most effective modification for a big T28 will be the FP 17 psi actuator. Many people have problems with boost dropping off in the upper RPM range and this has been proven over and over to help immensely, with the average gain being about 3 lbs/min of airflow (from the DSMLink forums).

I did not even think about this, and this is only $100. I will definately do this, regardless of what I decide. In fact, over 10 runs on the dyno, when the boost was dialed up past 18lbs, it always fell right back down a few psi. Thanks for this suggestion.

 

[pneumo]

A boost leak will make you run richer at WOT, plus it will rob power. This might explain the lean settings. So do a boost leak test.

I'll vote for fmic and injectors before the 50trim. I'm a big fan of pushing the turbo near it's limits before upgrading it. It works. Supporting mods make the power. The turbo is not the restriction until it's flowing above 80-85% of it's capacity.

At 15 psi of boost there is not enough difference between a T28 and a 50trim. At 20 psi the difference is bigger but not huge. OTOH the stock 2G IC (which is smaller than the 1G smic) is barely good enough for stock boost levels. You would feel a nice power increase with just a fmic. The airflow will also go up with a fmic, so you'll need bigger injectors too.

 

[hottboost]

Im running a SBR Big T28 @ 20Psi. I have spent the better part of my free time the last week to week and half trying to get it tuned. I have supporting mods except for stock smic. I have got it to a nice timing curve @ 20Psi but anything over that and timing goes to shit and I HAVE TRIED EVERY COMBINATION ON THE AFC to help it! If you get 550's and keep it under 20 you should be fine. And do your boost leak test!! Most people dont wanna hear it but its a fact. I try to do one every other oil change!

 

[Rice Over Wheat]

Ok, you all have convinced me. I will do the dejon fmic and injectors, then retune and see what I gain. After that its common sense what my next upgrade will be.

Thanks to everyone for the advice. I want to give rep pts but I dont see the button for it. Let me know how and everyone gets rep pts in this thread, thanks.

Btw, hottboost what numbers are you running on your T28 @ 20?

 

[hottboost]

I havent had it on the dyno yet. Just got it tuned out over the last few days. I want to be at least 275 WHP. But only time will tell. I gonna try to get on over the next 3 weeks. I sell cars so its real hard for me to find spare time. Good luck and let me know how it turns out!

 

[2gGSX]

560cc are fine depending on what boost, octane, and fuel pressure he's goin to run. Keep in mind, I believe he's on an AFC. I wouldn't go past 20psi cause that's when 93 octane starts to detonate. Yes, i do agree with the 650ccs. I wouldn't go any bigger as they will flood upon WOT. That's why some people have to issue with the AFC where WOT doesn't feel as fast as 60%...or they will sputter.

This was directed at the original idea of switching to a medium sized turbo (50 trim, green, etc). If the original poster is indeed staying with a T28 then I'd agree that 560's would be enough to reach 300 whp (albeit pushing them).

 

[exiletalon]

oldman- "boost leak test!"

 

[DGajre777]

Thanks to everyone for the advice. I want to give rep pts but I dont see the button for it. Let me know how and everyone gets rep pts in this thread, thanks.

It is the first thread after you click on newbie forum.
http://www.dsmtuners.com/forums/showthread.php?t=231141

Ok, you all have convinced me. I will do the dejon fmic and injectors, then retune and see what I gain. After that its common sense what my next upgrade will be.

If your goal is to push 300whp, get an ebay FMIC (cheap) or a 7" kit from www.extermeintercoolers.com who make a piping for the T28. Note that the 7" kit will not be enough for a 50 trim turbo unless you run at low boost.

If you decide to stick with the T28, as said before get 560 injectors. IF you then want to upgrade to a 50 trim turbo the 560s aren't going to cut it at high boost.

This is what the Big T28 should look like after you take your intake pipe off. If it doesn't look like the pic below, you don't have a Big T28. According to AGPs website, they sell the Big T28 NOT the T28. There is a difference.

 

[Ricardo]

I am the previous owner of that car, and I can assure you 100% that what he has on IS a BIG28, not a T-28. You can call AGP Turbo and ask them the sale of a t-28 with a t-25 core refund for Ricardo Naud a few years back, I am sure they will confirm you.

I know the source of power loss in this car and one person has got it right in this thread, but it has been completely ignored throughout this whole thread. The power loss comes from boost drop. This wastegate actuator and regular boost controller is simply not holding proper boost to the redline. That's why it jumps from ~268 torque to merely 242whp, because it makes peak torque then drops power from loosing boost. You need an electronic boost controller before anything else to hold proper boost to the redline. Even when I ran 20psi the turbo with c-16 it would still drop to ~11-12psi at 7000rpm unless I ran max boost.

BEFORE SPENDING ANY MONEY ON ANYTHING ELSE-- GET AN ELECTRONIC BOOST CONTROLLER. Also, you can reach your goal of 300whp with some cams on this turbo with the FMIC and Injectors.

I am available for any help. Garry knows his stuff, but he is used either using mitsubishi turbos for smaller setups (16g's) or doing large setups and putting in big turbos (50 trim and above)-- not t-28s, also he doesnt daily drive this car. Pay attention, boost does drop at redline.

 

[Ricardo]

The stock SMIC is definitely not enough to push that turbo to its full potential (which by the way can get you to 300 whp). A FMIC may not be absolutely necessary, but in my opinion as well as others' you may as well. Beyond that and fuel mods your most effective modification for a big T28 will be the FP 17 psi actuator. Many people have problems with boost dropping off in the upper RPM range and this has been proven over and over to help immensely, with the average gain being about 3 lbs/min of airflow (from the DSMLink forums).

Listen to this guy, he's absolutely right. I would try this actuator if you dont want to spend money on electronic boost controller.

 

[Rice Over Wheat]

Thanks for the input...I gave rep pts to everyone in the thread who contributed.

I just bought an Eibach pro-kit / Tokico Illumina setup, however, so I'll be holding off on the fmic/turbo/injector upgrades. I'll definately buy the T-28 actuator though and see how that works.

Ricardo, I wasn't doubting the T28 per se, just that Garry was asking on the dyno if I was sure that was a T28 when he was looking at it. I wasn't sure if you put in the T28 or the guy before you did. Even if it had been a T25 I wouldn't be upset as the car had low miles and has been perfectly reliable -- I'm sitting at 85k now, bought it from you at 58k.

Check my PM...I suspect my loss of whp was due to the heavier and larger wheels. That was the only difference between the two dyno tunes over a year's time aside from humidity. 18" vs stock 16". That has to affect dyno pulls.

I'll try the actuator upgrade.

 

[zippyshoe]

Rice Over Wheat - On a sidenote, in your vehicle profile I noticed that you have a Whinebro 255lph fuel pump listed but no adjustable FPR listed. If this is the case and finances allow, you may want to upgrade to an adjustable FPR. This may allow you to achieve a more consistent tune and prevent FPR overrun. Hope this helps!

 

[Rice Over Wheat]

I'm not sure what that would do for me. I'm quite busy at this point in my life and haven't had much time to really educate myself about the car beyond the basic concepts so I just buy the parts and pay people with the skills and knowledge to install/tune them. For example, just swapping in the 17psi actuator will probably be challenging for me.

 

[Ricardo]

I'm not sure what that would do for me. I'm quite busy at this point in my life and haven't had much time to really educate myself about the car beyond the basic concepts so I just buy the parts and pay people with the skills and knowledge to install/tune them. For example, just swapping in the 17psi actuator will probably be challenging for me.

Hey Kevin, good to see you are still around.

It is a looooot of info you have to go through to get a good understanding about cars and engines, I can really understand your position. I had 2 more tuned cars after the DSM, done very different types of mods and I know there is still a lot more to learn. Sometimes I wonder what has this added to my professional life, because it has only made me more broke. Rationally it is not a wise thing to learn all this stuff, but if those short moments bring you enough enjoy, then I guess it makes sense.

Even if all of this just sounds very philosophical, I just want to say I am here to assist with anything you might need as I have already invested some of my time in learning some these things.

I also must say from all the 3 cars I have owned the DSM was my favorite and I am very sad I had to let it go. It is a very nice car and you are lucky to have it, even if it's not anything like a vette.

The actuator, I suggest have garry install it. I wouldn't know how to do it myself, I guess it's not complicated and I could do it if I took a look at it, but since it's such a small job... why not have a professional do it and pay the small price to ensure it's safely done.

As far as the Fuel Pressure Regulator, I would say that is a good tuning tool, but not completely necessary. The car has indeed elevated fuel pressure, but you can correct the mixture (not fuel pressure) with the AFC (it is probably already corrected since garry has done a dyno tune), so the engine will receive a more proper Air and Fuel Ratio. I would add the FPR later on after more performance mods to have the car 100%, but it shouldn't add any power, would probably just allow the car to run better (might increase mpg a bit too).

As far as the plans for the car, I still hold down my suggestion in this order:

1. 17psi Actuator (price: low)
2. Front mount intercooler (price: intermediate/high)
3. Injectors (price: intermediate/low)
4. BOV crush mod (price: very low). I recommend this because the installed BOV will leak at over 21psi. If crushed it may hold up to 30psi.

Once you have Injectors and FMIC you should be able to run at least 22psi, which will should be putting down AT LEAST 270whp. If you are still not satisfied by then...

4. Get Bigger turbo or cams. (price: intermediate/high) Bigger turbo will allow you to make lots more power, but may need a bottom end build up to take full advantage of its power. As for the cams, they will allow the car to pull harder at high RPMs, with the t-28 the gain you are looking is probably bout 20whp, but the numbers are not all as the car will run better because of the improved power/torque curve.

Also, I still suggest the Electronic Boost Controller. It's a very nifty tool. If I knew how much it helps I would've bought when I had the car. It corrects any boost spikes/boost drops. Maybe instead of the actuator you can try one of these? Remember, the actuator will only be good for that turbo, but the eBC you can use in any other car/turbo setup.

Guess this is it.

Ricardo.

 

[2gGSX]

Also, I still suggest the Electronic Boost Controller. It's a very nifty tool. If I knew how much it helps I would've bought when I had the car. It corrects any boost spikes/boost drops. Maybe instead of the actuator you can try one of these? Remember, the actuator will only be good for that turbo, but the eBC you can use in any other car/turbo setup.

Guess this is it.

Ricardo.

The problem with the turbo not holding boost is due to the wastegate actuator itself--it has nothing to do with boost control. The stock spring is just too soft to be compensated with any sort of boost control, and the only real way to fix it is to start off with a stiffer spring and increase boost from there.

 

[Ricardo]

The problem with the turbo not holding boost is due to the wastegate actuator itself--it has nothing to do with boost control. The stock spring is just too soft to be compensated with any sort of boost control, and the only real way to fix it is to start off with a stiffer spring and increase boost from there.

Cool beans. It may just be me who has been in love with electronic boost controllers, especially the fancy ones where you can set boost by RPM, which IMO are a great tool for fwd cars to launch. However, I had the impression that when I ran the car with c-16 on max boost I did have good boost to the redline. I can't be sure however as I only ran with race gas for a couple of times as it is not cheap.

You are probably right tough, as the first time I used I cranked the boost up to 20psi and I saw the boost drop to my frustration, after I bumped the boost slightly but still dropping. The way I found the car to pull the hardest was at max boost when the boost controller accidently fell off which I realize now it may mean the wastegate was completely close thus not putting the spring to work. My BOV would leak at ~21-22psi anyway so I didn't see much more boost than that. I trapped 106mph this way compared to a mere 98mph on pump gas and lower boost on the 1/4.