Smic vs fmic snail heads chime in!

klumklum Senior Wagonist
in Engine & Drivetrain
I'm looking to embark on my first turbo build it's not going to be any thing serious just want a little more power. It's going to be on a sohc zc with no mods , the motor has got maybe 10k miles on it since I swapped it and when I got it , the motor was still silver on the inside so i assume the mileage is very low . So my question is on a light psi turbo build does smic make a big difference compared to Fmic I got a little vent cutout in my hood I think it's be a prime location for a smic but am curious if I'd be cutting my self shorter than I am already with a low psi turbo.
also curious as to what trim turbo would be best for either low or top end I have looked at turbo builds but not a lot of info can be obtained from a lot of the threads I checked out .
i want to plan for a high end and a low end power so I can research the pros and cons a little more in depth

Comments

  • bkmc24bkmc24 Senior Wagonist
    What motor is it? Power goals? Spool goals?

    For a D series, if it it stock and you intend on keeping it so, ~200-220 is usually a solid power goal and keeping everything stock. A lot of D guys run T25's because they're cheap, spool very quickly and hold decently under low boost through the power band. If you are trying to make it cheap, but reliable, http://www.homemadeturbo.com/ is an awesome resource for info. Dseries.org will also have a lot of info.

    If it were me boosting, and wanted to stay quality yet reliable, go-autoworks.com is where I would buy my kit from. VERY comprehensive and the owner if a D series guy. They have a street kit for $2k that has solid upgrade options. I would upgrade to the GT28 and enjoy the ability to upgrade the motor and not have to touch the kit at all. Good luck man!
  • bkmc24bkmc24 Senior Wagonist
    Oh, and to answer the intercooler question, for the prices anymore, just buy a FMIC. Unless you can snag a free SMIC and can fit it properly, I wouldn't even waste my time on them. If you are hellbent on using a SMIC, I would vent the air to be routed from the bumper or under the car and out the hood similar to the S13 drift hoods for radiators. The main difference will be hard piping and soft piping(which you shouldn't run) and the surface area of the IC and it's ability to cool/heatsoak.
  • klumklum Senior Wagonist
    bkmc24 wrote: »
    Oh, and to answer the intercooler question, for the prices anymore, just buy a FMIC. Unless you can snag a free SMIC and can fit it properly, I wouldn't even waste my time on them. If you are hellbent on using a SMIC, I would vent the air to be routed from the bumper or under the car and out the hood similar to the S13 drift hoods for radiators. The main difference will be hard piping and soft piping(which you shouldn't run) and the surface area of the IC and it's ability to cool/heatsoak.
    i just figure the smic is smarter for me because i can keep it kind of discrete
    229.jpg
    thats the hood vent i got right now i plan on fabricating a cal induction type scoop for it and prop the hood in the back a little too
    i also heard you get quicker spools and more low end power with smic since its closer you have less piping and there fore less time to charge.
    and yea i think a little hole in the bumper with a tube directing air up to it would be a idea as well.

    i think a smic placed right there would be perfect like this guys
    14.jpg
    bkmc24 wrote: »
    What motor is it? Power goals? Spool goals?

    For a D series, if it it stock and you intend on keeping it so, ~200-220 is usually a solid power goal and keeping everything stock. A lot of D guys run T25's because they're cheap, spool very quickly and hold decently under low boost through the power band. If you are trying to make it cheap, but reliable, http://www.homemadeturbo.com/ is an awesome resource for info. Dseries.org will also have a lot of info.

    If it were me boosting, and wanted to stay quality yet reliable, go-autoworks.com is where I would buy my kit from. VERY comprehensive and the owner if a D series guy. They have a street kit for $2k that has solid upgrade options. I would upgrade to the GT28 and enjoy the ability to upgrade the motor and not have to touch the kit at all. Good luck man!
    my motor is a sohc ZC as mentioned in op, my goals are in the 200whp range just a reliable daily setup help me get on the fwy and have a little fun on there as well.
    I like to go on spirited drives through the turns and intend on tracking my car at events sometimes so i want the power low to mid range so im able to use it when powering thru turns instead of it being a surprise mid turn when reaching high rpms so it cant cut out at high either ( idk if im making sense any more )
    i did some research on that homemadeturbo website and came up with a parts list im looking for a cheap piece together build right now im lookin to buy mostly parts used.
    im thinking a td04/05 from wrx or t25 i dont know much about the trim sizes and what means what with all that so im just going off of others builds that are aimed at the power i want .
    i just read that smic are better for lower power builds and to go fmic when your lookin for like 350+ or something like that.
  • bkmc24bkmc24 Senior Wagonist
    The reason the spool is quicker is because there is less air travel from compressor to motor through a smaller IC than a larger. Piping length, width and bends also play a factor. I like the IC placement idea. I had a turbo F22 CB7 that I did that with and it was decent. I would suggest buying everything but the turbo used. I have seen too many people get fucked by shady dudes with turbos. You can buy a rebuilt T25 from Gpopshop for an okay price. Ask Drfink about his GT28. It's an amazing turbo and its power capability is unrivaled for its size. It's gonna be spendy though. You could "skimp" and get a journal bearing one and save a few hundred. Cast manifolds are very cheap, so may as well buy a new one of those so you can get the warranty. You could also get an HX exhaust manifold and T25 adaptor plate, but that is the ultra cheap route lol. As for the spacing the rear of the hood, it is kind of useless. That area is a high pressure zone, and by spacing it, it really doesn't allow much more cooling high pressure air through, if that makes sense. A way to help the cooling of the IC could be a cryo bar or build a slight shroud to divert the high pressure air around the vent, creating a lower pressure in the rear for the bumper air to want to flow through. All of this hassle is why I say just get an FMIC :)
  • klumklum Senior Wagonist
    bkmc24 wrote: »
    The reason the spool is quicker is because there is less air travel from compressor to motor through a smaller IC than a larger. Piping length, width and bends also play a factor. I like the IC placement idea. I had a turbo F22 CB7 that I did that with and it was decent. I would suggest buying everything but the turbo used. I have seen too many people get fucked by shady dudes with turbos. You can buy a rebuilt T25 from Gpopshop for an okay price. Ask Drfink about his GT28. It's an amazing turbo and its power capability is unrivaled for its size. It's gonna be spendy though. You could "skimp" and get a journal bearing one and save a few hundred. Cast manifolds are very cheap, so may as well buy a new one of those so you can get the warranty. You could also get an HX exhaust manifold and T25 adaptor plate, but that is the ultra cheap route lol. As for the spacing the rear of the hood, it is kind of useless. That area is a high pressure zone, and by spacing it, it really doesn't allow much more cooling high pressure air through, if that makes sense. A way to help the cooling of the IC could be a cryo bar or build a slight shroud to divert the high pressure air around the vent, creating a lower pressure in the rear for the bumper air to want to flow through. All of this hassle is why I say just get an FMIC :)
    I'm definitely going ball bearing and going for a smaller turbo with external waste gate , It's going to be water cooled (idk if all turbos come like that or not)
  • HaydzHaydz Moderator
    That intercooler pictured above appears to be from an R32 GTSt, they are mounted inside the bumper in the corner.
  • klumklum Senior Wagonist
    Haydz wrote: »
    That intercooler pictured above appears to be from an R32 GTSt, they are mounted inside the bumper in the corner.
    It does huh? I looked them up looks on point, this is from a eg I think it'd b a perfect place for a smic especially with my vent and with a pipe directing lower air upward
  • ragenasianragenasian Moderator
    Another cheap option for an intercooler is the RX7 top mount, or a long time ago I owned a Turbo Coupe T-Bird with the 2.3 turbo, it also had a top mount that can be had pretty cheap. I scored my Rx7 cooler at the junkyard for 15 bucks with aftermarket BOV still attached. Basically used it on my ae86 for the same reason you are thinking. Not some big bling front mount, I didn't have to chop the front end all to sh@# to run piping either (plus having a mint hood and a junkhood to swap out helps). I cut my pipe length in half by doing it this way. I have the bling bling front mounts too but too much bling brings unwanted attention. You could always do what I did for another build and get a FMIC and paint it all black if you want discreet, but the less piping the better, at least in my world.

    Have you ever thought of the water cooled intercoolers? They are a bit more in terms of price but this might help out if you are concerned about heat issues or location.
  • bkmc24bkmc24 Senior Wagonist
    I'm pretty sure water cooled turbos are all ball bearing and oil cooled are journal bearings. Expect the turbo to be spendy if you want ball bearing lol.


    Air to water intercoolers are more efficient for straight line car that isn't a daily. The efficiency is substantially better for short periods but the heat soak is worse than an air to air intercooler. I have done a lot of reading on them lol.
  • klumklum Senior Wagonist
    ragenasian wrote: »
    Another cheap option for an intercooler is the RX7 top mount, or a long time ago I owned a Turbo Coupe T-Bird with the 2.3 turbo, it also had a top mount that can be had pretty cheap. I scored my Rx7 cooler at the junkyard for 15 bucks with aftermarket BOV still attached. Basically used it on my ae86 for the same reason you are thinking. Not some big bling front mount, I didn't have to chop the front end all to sh@# to run piping either (plus having a mint hood and a junkhood to swap out helps). I cut my pipe length in half by doing it this way. I have the bling bling front mounts too but too much bling brings unwanted attention. You could always do what I did for another build and get a FMIC and paint it all black if you want discreet, but the less piping the better, at least in my world.

    Have you ever thought of the water cooled intercoolers? They are a bit more in terms of price but this might help out if you are concerned about heat issues or location.

    i can dig it thats my issue i just belive that dseries arent all that to the point you can say it needs a fmic , i mean if all these other cars have smic stock and they weigh more and have just slightly bigger motors theres no reason a car like the wagon cant preform using the same layout
  • klumklum Senior Wagonist
    bkmc24 wrote: »
    I'm pretty sure water cooled turbos are all ball bearing and oil cooled are journal bearings. Expect the turbo to be spendy if you want ball bearing lol.


    Air to water intercoolers are more efficient for straight line car that isn't a daily. The efficiency is substantially better for short periods but the heat soak is worse than an air to air intercooler. I have done a lot of reading on them lol.
    interesting so do you think internal or external waste gates matter id think combining a water cooled intercooler and turbo with external waste gate would be easily manageable as a DD
  • bkmc24bkmc24 Senior Wagonist
    https://www.frozenboost.com/ is the website I would look into for air to water. I wouldn't do it for a DD. Heatsoak will really kill the power.

    Internal wastegates are okay, but are limiting the power capability. External gates can have their springs swapped to adjust boost ranges. Given what you want to do, and that it is your first time, an internally gated T25 would work just fine.

    To counter your "need for a FMIC" statement, there is no need for an intercooler at all. The concept of a turbo will work all the same. The efficiency, however, will be way less due to the AIT's being pumped into the motor from an exhausted heated turbo. That being said, the SMIC will work okay because it will still allow surface area for heat exchange, but not as well as a FMIC.

    For it being your first time boosting, keep it simple. What I would do if I were you, is buy the entire turbo set-up as a kit. Buy the Go-Auto street kit, and upgrade it to the GT28 ball bearing. Contact Greg at Go-Auto and tell him your set-up and vehicle and he will make it happen. From there, look into tuning, fuel, clutch and axles. You're overthinking everything and wanting to be unique by a lot too much for a first time boost lol.
  • klumklum Senior Wagonist
    i dont see how heatsoak would be a issue if its a light psi its not like im going to be smashing the hell out of the motor everywhere i go ? maybe my understanding of heatsoak isnt right.
    can i reroute the wiper water pump to spray water on the intercooler to prevent heat soak?

    Garrett GT1752
    comes off a saab 9-5 theres one at a local pick and pull im thinking the turbo can be had for cheap but im not sure if this would satisfy the desired goals with my build
  • bkmc24bkmc24 Senior Wagonist
    They make cryo-coolers for them that would work better than water.

    Why would you ever WANT less efficiency than you can have? Price won't be much different, so why bother?
  • drfinkdrfink Wagonist
    Rerouting the wiper pump is actually a pretty cool idea lol
  • klumklum Senior Wagonist
    drfink wrote: »
    Rerouting the wiper pump is actually a pretty cool idea lol

    thanks i thought that was pretty smart too but know nothing about turbos
  • klumklum Senior Wagonist
    drfink wrote: »
    Rerouting the wiper pump is actually a pretty cool idea lol

    thanks i thought that was pretty smart too but know nothing about turbos
  • HaydzHaydz Moderator
    Bit late I know, but on the JDM Shuttles there is headlight washers on some models. I don't know if the bottle has three pumps - front, rear and headlights or if the headlights have a separate bottle. You could investigate that setup for an OE looking install.
  • klumklum Senior Wagonist
    id just reroute the tube for the rear wiper or just eliminate the windshield one and route the tubes to the IC like that
    but it wouldnt be nothin to wire up a new button and motor specifically for that or a seperate resiviour all together
  • greenteagodgreenteagod Moderator
    Not sure if it holds true for our engines, but the general consensus in Subaru world is unless you're pushing some serious numbers, there's little benefit to having a front mount. There are improvements to be made to the top mount/side mount before going to a front mount is necessary.

    That said, that's a lot of what they're factory engineered for. So that motor design might work with that a little better. Though I do love that pic you posted showing the side mount there. That looks like a perfect spot for it, almost so much that I'd be tempted to scrap my own plans for a rear mount turbo.
  • klumklum Senior Wagonist
    i know right its a perfect location in my opinion its actually one of the first pics that popped up in google when i typed in fmic and i was surprised to see it was a eg but it gave me the idea to scrap my intial plans for use of the air vent in my hood i made and want to go with this.
    thats some good info to know tho . i look at it like electricity (air flow) longer the piping or wire more you lose
  • greenteagodgreenteagod Moderator
    Hell I'd probably just set up that air vent in such a fashion that the intercooler had a way to seal up against the hood that way that air vent feeds it appropriately. It looks like there'd be enough room underneath for a fan as well. Maybe something like this but on the underside. With a shroud and everything to keep as much air moving through it as possible.

    128.jpg

    Where it's sitting, you could even go as far as building some custom housing around it, with some aluminized insulation on it to help reflect engine bay heat away from it. Could be fun =)

    If you do it, document the process this type of stuff is fun.
  • klumklum Senior Wagonist
    Oh i see now that would be sick!
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