Twin turbo SHO Merkur swap thread (A.K.A Stupid High Output)

Discussion in 'Tuning ~ Supercharger ~ Turbo ~ Nitrous Upgrades' started by MerkXRTurbo, Oct 3, 2008.

  1. MerkXRTurbo

    MerkXRTurbo New Member

    Joined:
    Feb 28, 2005
    Messages:
    229
    Likes Received:
    60
    Location:
    Vancouver, WA
    Hey guys, many of you are aware of the project that I've got in the works (it actually started when I bought my 3.0 a couple years ago). I am taking a 3.0 with a low compression rebuild, twin turbos, and sticking it into my 1989 Merkur XR4Ti. Right off the bat I'm hoping to have power levels in the 400-500hp range. Anyway, I have the engine (in pieces), I have a T5 from a V8 Mustang, and I have the car with no drive train. I started by upgrading to a LSD rear end. For this I used a 10 bolt 7.5" carrier from a 1987 Trans Am and modified it to fit inside of the factory Merkur IRS case:

    Factory XR4Ti open differential on the left, Trans Am LSD on the right. The end bearings are actually the same part# for both carriers if you look in a parts catalog, and the splines on the XR4Ti axle stubs are the same as the splines on the GM axles. If you look VERY carefully you can see that the axle hole in the Ford is a tiny bit bigger, so the axle stubs had to be turned down in order to fit into the GM unit:

    [​IMG]

    [​IMG]

    Here is the LSD with one bearing race removed. It is required, in addition to case grinding, to install it into the case. Due to its larger girth, you are not able to turn it into place with the end bearing retainers removed.

    [​IMG]

    Here is the factory XR4Ti ring gear bolted by two bolts to the GM carrier. This photo shows that the holes line up with no modification required:

    [​IMG]

    [​IMG]

    The GM carrier is not quite as long, from bearing to bearing, as the Ford carrier, and it is also designed for a larger pinion gear than the XR4Ti has, so the ring gear landing is too far to the left to allow the gears to make contact. Spacers had to be machined, one to but the ring gear up against the pinion, and another went underneath the bearing race to get the overall height of the carrier correct for the case. After that was all taken care of I found out that the pinion gear rubbed the carrier, the carrier was turned down 17 thousandths:

    [​IMG]

    In the photo above you can see the grinding on the left inside of the case to allow the carrier to BARELY slip in. Underneath the ring gear you can see the .550" spacer required to get it over. The silver stripe is where the carrier was turned down for pinion clearance. Last but not least you can see the .362" spacer that contributed to the carrier's overall height to allow it to ride in the bearing retainers as designed.

    I bolted my Aerostar bellhousing to the block to take measurements for motor mounts. The top of the bell hit the firewall tunnel, so I cut off the strength ridges.

    Before:

    [​IMG]

    After:

    [​IMG]

    Unfortunately that did not provide enough clearance, so I got out the sawzall and cut out the tunnel. It is out of my way... for the moment anyway.

    I have an earlier V8 T5 (got it for $75, so I can afford to break it) so I needed the '94/'95 input shaft, which is approximately .5" longer, which will be required to make up for the thickness of the bellhousing adapter. I just received that, along with a steel front bearing retainer, that not only does not wear out, but it won't flex under torque like the factory aluminum ones do:

    [​IMG]

    [​IMG]

    What may or may not be known by this community is that the SHO crankshaft will accept a 2.3 Ford pilot bearing PERFECTLY! That means that all that will be required as far as that is concerned is that the pilot of the input shaft be turned down from V8 diameter (.668") to 2.3 diameter (.591").

    Well that's it for now. I have the driver's side motor mount done, but still working on the passenger side. I'll have more updates as I go.
     
    Last edited: Aug 10, 2009
    SuperHO likes this.
  2. Sho Amo

    Sho Amo SmkTyresntDrugs

    Joined:
    Feb 23, 2006
    Messages:
    3,298
    Likes Received:
    854
    Location:
    Olney, Md
    how much boost?
     
  3. MerkXRTurbo

    MerkXRTurbo New Member

    Joined:
    Feb 28, 2005
    Messages:
    229
    Likes Received:
    60
    Location:
    Vancouver, WA
    I'm building it for 8.0:1 compression and planning on 20-23psi on pump gas, depending on how much I am able to get away with before knock occurs. Of course I will play with boost vs. timing to figure out the perfect balance of things for max power.

    I have chosen Mitsubishi TD04L-13T WRX turbos because I dug through pretty much every compressor map available online, and those are the only ones that put my requirements on the center island. My projected power levels require around 20lb/min of air for each cylinder bank (which is roughly .14m3/sec on the X-axis of the map below), and with 23lbs of boost (roughly 2.5 pressure ratio on thye Y-axis), you can see that it falls in the center island, which means that the compressor is nicely matched for the setup, and it's not surging attempting to feed too small amount of air at a high pressure, nor is it drastically heating the air up any more than necessary because it's pushing more air than it's designed to:

    [​IMG]

    I'm also confident with the factory turbine wheels and housings, as the WRX crowd runs 250-275hp off of them no problem... if they become a restriction then that means that I am running at least 500hp, so I'll be a happy man!
     
    SuperHO likes this.
  4. pimp

    pimp New Member

    Joined:
    Jun 5, 2004
    Messages:
    175
    Likes Received:
    10
    Occupation:
    Recouping from surgery
    Location:
    Orange County NY
    Yes, and with all your hard work you should be.It takes a real strong person to dig and try and to go where no one really does and im sure theres pain also.Good luck and im sure lots will be watching your posts.
     
    MerkXRTurbo likes this.
  5. Off Road SHO

    Off Road SHO Moderator Staff Member

    Joined:
    Jan 16, 2002
    Messages:
    5,682
    Likes Received:
    1,276
    Occupation:
    technologist geek
    Location:
    Arizona
    If you don't want to machine down the input shaft, I have both Oil-Lite Bronze bushings and needle bearings to fit the T-5 and the SHO crank. PM me if you want one of either.

    Tom
     
    MerkXRTurbo likes this.
  6. yamahaSHO

    yamahaSHO E85 whore

    Joined:
    Jul 25, 2002
    Messages:
    10,595
    Likes Received:
    2,375
    Occupation:
    FEMA... You like camping?
    Location:
    Colorado
    8:1 compression is very low and IMHO, MUCH lower than you need to go for 400-500hp. In fact, you can make those power levels safely with a completely stock motor and boost. As a recommendation, I would go with 9:1 rather than 8:1 which would be very safe. I'm running 9.5:1 at 530 untuned bhp and no knock issues.

    Other than that, I'm looking forward to this build. I know Tom was planning something like this, but that was some time ago.
     
  7. Sho Amo

    Sho Amo SmkTyresntDrugs

    Joined:
    Feb 23, 2006
    Messages:
    3,298
    Likes Received:
    854
    Location:
    Olney, Md
    sweet. glad you did something that most people dont do on this forum. turbo mapping
     
  8. shospeed

    shospeed Member

    Joined:
    May 8, 2006
    Messages:
    328
    Likes Received:
    24
    Location:
    austin tx
    Any pics of the acutal turbo set up?
    just wondering how are you going to fit that !
     
  9. MerkXRTurbo

    MerkXRTurbo New Member

    Joined:
    Feb 28, 2005
    Messages:
    229
    Likes Received:
    60
    Location:
    Vancouver, WA
    I didn't realize that there were needle bearings that would fit! I know that there are bronze bushings, as the 2.3 guys use them to run a V8 T5 behind their engines, but some have had problems with premature wear and destroyed input shaft bearings due to it.

    Yes, I am VERY interested in one of the needle bearing setups. I'll PM you in a bit.

    I have built and driven many turbocharged vehicles and 8.0:1 compression is where I think it is best suited for a street car. The manufacturers seem to agree with this, as this is in the neighborhood that they generally tend to put their boosted vehicles. I know that it's not as good for off-boost performance, but I have found that turbo matching is a bigger aspect. When my car had the modded 2.3T in it I was keeping up off the line with V8s, modified turbo AWD cars (DSMs, WRXs, EVOs, etc.), and things like that which are known to REALLY launch. I found myself never more than a fender behind at the top of 1st gear. Shifting into second I would pull even more, and 3rd, and so on.

    400-500hp is my worst case scenario. If it happens to be a WAY bigger number than that then I will be thrilled (and probably replacing drive train parts :bonk:)! Either way, I would like to be making my numbers on pump gas, although it's likely that it would see some race fuel and even bigger boost from time to time.

    I'm actually not that far yet, nor do I have the turbochargers. I'm not worried though... low mileage WRX turbos are everywhere. You might even be able to find them at Wal-Mart:rofl:. I've got the bare block in the engine bay for motor mount fabrication, however, I can assure that this setup has been done once before (actually twice, by the same guy, but the 1st was a single turbo setup) using much larger T3 turbos than I am. I have a set of header flanges from SHOsource, (which are just an incredible deal - big thanks to those two), and some butt weld fittings on hand, so I will be building my headers a bit later on. The BIGGEST expense from here will be the pistons, and those won't be made until I get everything else in order, that way I don't have a brand new built engine that's just sitting, possibly getting moisture in it, and nasty greasy hand prints as I mock stuff up.
     
  10. yamahaSHO

    yamahaSHO E85 whore

    Joined:
    Jul 25, 2002
    Messages:
    10,595
    Likes Received:
    2,375
    Occupation:
    FEMA... You like camping?
    Location:
    Colorado
    I understand you have experience with building (and driving?) turbocharged motors, however, I am giving you my experience with the SHO motor. I am hitting 530hp (16 PSI) on a bad tune and pump gas (all from a power robbing SC). Pat's 9:1 motor has seen 520Whp without any charge cooling at the time.

    CR isn't the entire equation as head design and cooling will play and even bigger role (within reason). The reason why I'm saying anything is because the 20-23 PSI you're looking to attain is attainable at 9:1. Again, just stating my own experienes with the SHO motor (which is pretty vast when it comes to boosting), so don't take it the wrong way.

    I'll keep my mouth shut now as some people think I'm condensending:wave:
     
  11. Toolman

    Toolman Boost it! Staff Member Club Mod

    Joined:
    Jan 28, 2001
    Messages:
    6,148
    Likes Received:
    2,632
    Occupation:
    Firefighter
    Location:
    Grand Lake, Oklahoma, USA
    20+psi will for sure put you over 500hp. According to the compressor maps I have seen for my last two turbo setups, I should have been making less power for my given ratio. Expect your setup to do likewise.

    TT
     
  12. MerkXRTurbo

    MerkXRTurbo New Member

    Joined:
    Feb 28, 2005
    Messages:
    229
    Likes Received:
    60
    Location:
    Vancouver, WA
    Thanks guys, and YamahaSHO, I'll take your considerations to heart!
     
  13. shospeed

    shospeed Member

    Joined:
    May 8, 2006
    Messages:
    328
    Likes Received:
    24
    Location:
    austin tx
    Are you mounting the turbos right after the manifuls or in a remote location?
     
  14. MerkXRTurbo

    MerkXRTurbo New Member

    Joined:
    Feb 28, 2005
    Messages:
    229
    Likes Received:
    60
    Location:
    Vancouver, WA
    On the manifolds. :thumb:
     
  15. Off Road SHO

    Off Road SHO Moderator Staff Member

    Joined:
    Jan 16, 2002
    Messages:
    5,682
    Likes Received:
    1,276
    Occupation:
    technologist geek
    Location:
    Arizona
    So, are you going to weld a T3 flange to the cast iron exhaust manifolds? Or use a short piece of the stock down pipe and re-use the stock flare.

    I think a talented machinist could machine a V-band end on our stock manifolds, and straighten it out at the same time.

    Good idea keeping the turbos close to the explosions. Your spool time will be measured in femto-seconds, maybe even atto-seconds.:dribble:

    Tom
     
  16. MerkXRTurbo

    MerkXRTurbo New Member

    Joined:
    Feb 28, 2005
    Messages:
    229
    Likes Received:
    60
    Location:
    Vancouver, WA
    Nope, I'm going to be building my own headers out of schedule 40 (~1/8" thick) butt weld fittings (AKA Weld-els). As I said, I've already got the flanges from SHOshop.

    Yep, as heat is lost in the headers so is energy that is required to spool the turbos. My headers will be as short as possible, with the fewest bends possible. :thumb:
     
  17. SHO_DOODmorrris

    SHO_DOODmorrris Owner & Fanatic

    Joined:
    Sep 19, 2005
    Messages:
    1,062
    Likes Received:
    110
    Location:
    Alberta
    SHOsource i think you mean:wave:
     
  18. SuperHO

    SuperHO Mental Patient

    Joined:
    Sep 8, 2002
    Messages:
    5,695
    Likes Received:
    1,365
    Occupation:
    Dinner Delivery
    Location:
    St. Joe, MI
    Home Page:
    subscribed! Shit's gonna be sick, yo!
     
  19. MerkXRTurbo

    MerkXRTurbo New Member

    Joined:
    Feb 28, 2005
    Messages:
    229
    Likes Received:
    60
    Location:
    Vancouver, WA
    Whoops, my bad! Yes, SHOsource is what I meant. :oops:
     
  20. SHO_DOODmorrris

    SHO_DOODmorrris Owner & Fanatic

    Joined:
    Sep 19, 2005
    Messages:
    1,062
    Likes Received:
    110
    Location:
    Alberta
    :swing: lol i know its hard to keep track of all our aftermarket suppliers. :nut: lol
     

Share This Page

If you wish to help keep SHOforum running, please click the donation button below