Big 16G questions.

[Nekoni]

First off my current modifications:
2g Exhaust manifold
3" turboback exhaust

Mods buying at the same time:
Dejon Tools SMIC kit (intercooler, uicp, licp)

1. This turbo is a direct bolt in for my 1990 GSX right?
2. If I get it ported with a larger wastegate flapper, am I still going to be screwed when it comes to boost creep due to this exhaust?
3. Anything anybody can suggest before I buy it?

 

[VTRICCO]

ported o2 housing, logger, injectors, piggy back fuel computer, fuel pump and regulator

 

[Nekoni]

Not going to increase the boost level, I'm going to run my vac line directly from my intake to the wastegate.

 

[VTRICCO]

those are all things i suggest you get in addition to the turbo

 

[greddyturbo19]

why not get a front mount intercooler instead of a sidemount?? they got some cheap ones on ebay that will be better than a sidemount. and plus your car looks ten times better with the fmic

 

[Nekoni]

those are all things i suggest you get in addition to the turbo

Will a 16g at stock boost and a different intercooler setup really require me to change my fuel map like that? Wouldn't the stock MAF pick up on the increase in airflow? I mean I'd like to keep this car under 250hp...

Although injectors, pump, regulator I might agree with you, I believe DSMs run at what, 80% duty cycle?

Edit:

Greddyturbo19 - a "cool looking" fmic isn't really my thing. If I call up Dejon tools and they can't get me a better deal, then I might go with one simply because you're right, it would probably be cheaper.

 

[greddyturbo19]

When I First Bought My Eclipse I Had A Evo Iii 16g Turbo And It Was At 12psi On Low And 18psi On High On A Stock Fuel System With A Fmic And Did Just Fine. Then I Upgraded To A Greddy 18g Turbo With The Same Boost Levels And Never Had A Problem With The Stock Fuel System.

 

[thorlief4g63]

I would suggest a hard intake pipe and good filter, and if you go with bigger injectors I would also say a MAF-T setup would be smart. Good Luck

 

[Nekoni]

Greddy - thank you. I kinda figured at 12psi I would could make the stock fuel system work. I've already got a logger so I'll just keep an eye on it.

 

[DSMvroom]

If you're looking to stay under 250hp, save some money and stick with the 14b. That turbo will make 250hp without too much of a sweat.

 

[210 dsm]

you'll be just fine with that set up. i have the same car as you and a 16g. at one point i had the boost at 20 and i dident have any fuel cut problems. thats with a stock fuel system. also i agree with dsmvroom, the 14b will support a push to 250hp with your mods. but keep in mind you'll get way better spool up with the 16g. i get full boost at 3100 rpms.

 

[DSMsOwnYourV8]

you'll be just fine with that set up. i have the same car as you and a 16g. at one point i had the boost at 20 and i dident have any fuel cut problems. thats with a stock fuel system. also i agree with dsmvroom, the 14b will support a push to 250hp with your mods. but keep in mind you'll get way better spool up with the 16g. i get full boost at 3100 rpms.

You may have not been getting fuelcut, but I bet your engine was knocking like a mofo. 20psi is too much boost with a 16g on the stock fuel system. To the op if you're going to run a bigger turbo, you will need a fuel pump, since you only want 250hp, a Walbro 190 will do you fine. You might need a fpr, but probably not. If you decide to turn up the boost you will need some bigger injectors and a fmic.

 

[squyres2005]

why not get a front mount intercooler instead of a sidemount?? they got some cheap ones on ebay that will be better than a sidemount. and plus your car looks ten times better with the fmic

Oh yes, FMIC's are way cool, besides it really still doesnt detract frome the "sleeper" image. I had some kids in a honda tell me i needed to get some mesh to hide my
"radiator"

 

[Splitpi]

Will a 16g at stock boost and a different intercooler setup really require me to change my fuel map like that? Wouldn't the stock MAF pick up on the increase in airflow? I mean I'd like to keep this car under 250hp...

Your fine... I'm running 202 at the wheel on a big 16G at wastegate pressure.... thats ~+/- 240 hp at the crank. However, I would recommend a rewired fuel pump... its nearly free to do ~$15-$30 and makes a world of difference on the fuel pump flow rates. However, if you want to make real power, you will need something to tune. With the factory 2G tune I was making 191 hp at the wheel. Tuning added an extra 11 hp alone on the same boost levels.

Although injectors, pump, regulator I might agree with you, I believe DSMs run at what, 80% duty cycle?

My 450's are at ~75% IDC at 202 wheel hp.

 

[Nekoni]

Thanks for the information everybody. But it's just killing me a little simply because I'm not looking at making a whole lot of power with this car. I'm only replacing the turbo because my current turbo is starting to scrape the compressor housing. I wont buy used turbos because I've been burned on that before (Looked like the guy was running dyno oil and changed every 20k miles, the inside was coked up pretty badly). I only figure if I'm going to buy a new turbo, I might as well just get a 16g.

Not turning the boost up at all on this thing. But I do have plans to run an 8ga live wire directly to my fuel pump (fused and on the proper relay of course). I will keep an eye on my knock and injector duty cycle but I'm kinda doubting I'm going to need an increased fuel supply beyond the rewire. We'll see.

 

[DSMvroom]

you'll be just fine with that set up. i have the same car as you and a 16g. at one point i had the boost at 20 and i dident have any fuel cut problems. thats with a stock fuel system. also i agree with dsmvroom, the 14b will support a push to 250hp with your mods. but keep in mind you'll get way better spool up with the 16g. i get full boost at 3100 rpms.

Are you trying to imply that a larger turbo spools faster than a smaller one?
I'm not saying it's impossible, but highly unlikely.

Op if you are going to upgrade to a 16g because your 14b is failing, you really should get fuel support. It would be considered "irresponsible" to run 16psi without at the very least datalogging to see if your car really is ok or not . . . lest you inadvertantly need to replace the rest of your setup (read: your motor)

If there is someone on that runs a 16g with stock fuel/no tune and has some logs to post (and show the engine running fine at 16psi), I'd possibly consider that a marginally satisfactory example. . . maybe. Each car is different and your mileage WILL vary.

 

[dsm-onster]

Simply, a 14b is good for a bit over 300whp. You want to run under 250whp. Stick with a 14b. Save money for a logger and be happy you will have lighning fast boost and plenty of turbo for future upgrades. Look at rebuilding your 14b. It will be cheaper than buying a new, modified 16g. Why not get a 16g? It spools slower and is way overkill.

 

[DSMsOwnYourV8]

Are you trying to imply that a larger turbo spools faster than a smaller one?
I'm not saying it's impossible, but highly unlikely.

Op if you are going to upgrade to a 16g because your 14b is failing, you really should get fuel support. It would be considered "irresponsible" to run 16psi without at the very least datalogging to see if your car really is ok or not . . . lest you inadvertantly need to replace the rest of your setup (read: your motor)

If there is someone on that runs a 16g with stock fuel/no tune and has some logs to post (and show the engine running fine at 16psi), I'd possibly consider that a marginally satisfactory example. . . maybe. Each car is different and your mileage WILL vary.

Yeah I was thinking that too. I guess 16g's spool faster than 14b's, and 20psi is safe to run on a 16g with a stock fuel system.

 

[jking29]

For your goals keep the 14b and just port the inlet and pay special attention to the opening to the wastegate. My suggestion would be a logger, afc, fuel pump rewire, port turbine housing and o2 housing and a water injection kit with 2 nozzles, 1 pre-intercooler and 1 on throttle body elbow. Should be pretty easy to reach your goals with these mods alone.

 

[Nekoni]

My biggest thing with the 14b is that for me, it spools TOO soon and not only does it dip off top end but it also promotes boost creep. I figure with a slightly larger turbo, increase my turbo threshold, and if I get an Evo III style I believe those have a slightly different setup on the hot side to help aid in boost control (speaking not only of the size, but the wastegate flow design).

Personally, I think they did a good job on the compressor side for a factory turbo, but if you're going to mate it to an engine that redlines at 7k RPM (assuming the camshafts are ground for power that high), why not match the turbo for it and increase your threshold which will also increase power outside of boost due to less backpressure.

Stop me here if I'm wrong by any means. But I would rather use a turbo more suited for this engine and like I said, I do not believe it was properly designed from the factory. Granted it gives you faster spool, but by no means efficient flow with regards to engine design. I feel the 16g may do a better job with this in mind.

By the way, I am using a pocket logger. It's by no means even a good setup, but at least it gives me some feedback.

Once again, I have no goals for this car, I just wanna keep it below 250hp, if I had a chance to put all this back on and make factory power, I would do it, but I just don't agree with how Mitsubishi set it up. If I have to make more power doing what I'm doing, so be it, but that's not my goal. I have other cars that I race, and I don't feel like racing a DSM with one of, if not THE weakest drivetrain they made.

 

[DSMvroom]

16g turbos have a higher tendency to creep because they seem to be more at home at high boost. My evoIII for example will creep to 21psi, no matter what boost below 21 it is set to. I'm not sure how bad the creep is for a big 16g, but I imagine it isn't too much less than that.

As far as a 14b spooling too quickly and falling off at the top end:
I disagree with it spooling too quickly, especially with AWD. Remember that even Mitsu thought it spooled too slow, hence the downgrade to a smaller t25 for the 2Gs.
Also I'd bet that everyone on the forum who runs a 14b at higher boost (>16psi) can confirm that although it might drop off, it can hold at least 18psi by redline. This is more than enough to get you 250hp, and then some.

You should really think hard about what your goals for the car really are. Don't let yourself think that you are only looking for 250hp if in the back of your head, you know you want more. It sounds to me like you are trying to convince yourself that 250hp is what you want

 

[dsm-onster]

My biggest thing with the 14b is that for me, it spools TOO soon and not only does it dip off top end but it also promotes boost creep. I figure with a slightly larger turbo, increase my turbo threshold, and if I get an Evo III style I believe those have a slightly different setup on the hot side to help aid in boost control (speaking not only of the size, but the wastegate flow design).

Personally, I think they did a good job on the compressor side for a factory turbo, but if you're going to mate it to an engine that redlines at 7k RPM (assuming the camshafts are ground for power that high), why not match the turbo for it and increase your threshold which will also increase power outside of boost due to less backpressure.

Stop me here if I'm wrong by any means. But I would rather use a turbo more suited for this engine and like I said, I do not believe it was properly designed from the factory. Granted it gives you faster spool, but by no means efficient flow with regards to engine design. I feel the 16g may do a better job with this in mind.

By the way, I am using a pocket logger. It's by no means even a good setup, but at least it gives me some feedback.

Once again, I have no goals for this car, I just wanna keep it below 250hp, if I had a chance to put all this back on and make factory power, I would do it, but I just don't agree with how Mitsubishi set it up. If I have to make more power doing what I'm doing, so be it, but that's not my goal. I have other cars that I race, and I don't feel like racing a DSM with one of, if not THE weakest drivetrain they made.

I think mitsu did the opposite. The drop off in power you feel is because of the cam design not the turbine. If you're working with stockish power levels especially. Also the stock manifold is the same manifold used on the N/A 4g63. Which provides much lowend torque at the expense of some topend. Then Mitsu chose to put the largest turbine wheel ever to be installed on a japanese 4-cylinder into the stock 14b turbo. This is the same turbine wheel as the 16g. The only difference is the turbine housing. Apparently mitsu felt the td05h turbine wheel was laggy enough and used a smaller housing to bring on spool quicker. I think it matchs the stock cam profile perfectly. And goes hand in hand with the stock intake manifold that peters out at about 6K.

If you want 16g topend, swap on a 7cm^2 turbine housing from a blown 16g or they sell for rather cheap by itself.

 

[Nekoni]

I can understand and agree with that, I've been out of DSMs for awhile and forgot the camshafts do some real good for the top end of these cars. I always thought it was odd that the N/A intake manifold was the same as well, I with they would have gone with shorter runners. I donno, that's the weirdest thing with these cars is nothing seems to jive like it should.

While I have you, what is a decently effective way to get rid of boost creep? I don't have specs on both turbos but I know STIs with their 16g don't have as much of a problem, I mean creeping to 21-23psi from 12 is just insane. Is an external wastegate the only way?

 

[AlphaAssault]

You may have not been getting fuelcut, but I bet your engine was knocking like a mofo. 20psi is too much boost with a 16g on the stock fuel system. To the op if you're going to run a bigger turbo, you will need a fuel pump, since you only want 250hp, a Walbro 190 will do you fine. You might need a fpr, but probably not. If you decide to turn up the boost you will need some bigger injectors and a fmic.

in this particular setup, wouldnt 20psi on the stock fuel system result in scoring on the spark plugs? knocking is a result of too much air and not enough fuel, correct?

 

[oldman420]

I suggest the hrc super16g to everyone that isn't looking for huge power. I have one that I hooked up directly to the BCS and it runs at 12psi constantly, no creep. I have since then done some more upgrades but when thats all i had it ran great. Exhaust temps were a bit high, but i imagine if i had done a re-wire on the pump and a new fuel filter i would have been perfectly fine. The super16g is a bit more expensive but makes really good power, spools at around 3200 rpm and holds until redline.