Welcome to the North American Subaru Impreza Owners Club Thursday March 28, 2024
Home Forums Images WikiNASIOC Products Store Modifications Upgrade Garage
NASIOC
Go Back   NASIOC > NASIOC Technical > Built Motor Discussion

Welcome to NASIOC - The world's largest online community for Subaru enthusiasts!
Welcome to the NASIOC.com Subaru forum.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, free of charge, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, so please join our community today!

If you have any problems with the registration process or your account login, please contact us.







* As an Amazon Associate I earn from qualifying purchases. 
* Registered users of the site do not see these ads. 
Reply
 
Thread Tools Display Modes
Old 09-23-2014, 12:01 PM   #76
68Cadillac
Scooby Specialist
 
Member#: 95901
Join Date: Sep 2005
Default

Posted this in another thread a while back but it's for this build so:

Based on some formulas from this thread on Nabisco I overlaid how much air my planned 2.334 liter motor can pump at various RPM's and Pressure Ratio's (PR). I'm trying to choose the correct size turbo for SCCA's X Prepared class. X Axis is Lb of Air/Min Pumped (Lb/Min). Y Axis is Pressure Ratio (a.k.a. Boost). The colored lines represent how much air can be pumped through the 2.334 liter motor at a given RPM as the PR changes. This is a purely mathematical exercise assuming 100% efficiency at Sea Level Air pressure.

PR of 0.0 = Perfect Vacuum
PR of 1.0 = Zero Boost, Wide Open Throttle
PR of 1.5 = 7.4 psi of boost
PR of 2.0 = 14.7 psi of boost
PR of 2.5 = 22.1 psi of boost
PR of 3.0 = 29.4 psi of boost
PR of 4.0 = 44.1 psi of boost


Here's the GTX2867R compressor map under a 2.334L motor at various RPM's and Pressure Ratio's. At 2000 RPM the turbo's starting to get past the surge line (beginning to spool up). Turbo's full spooled at 3000RPM for Pressure Ratios 2.0 - 3.0. Peak HP should hit about 5000 - 5500 RPM, pushing 46 lb/min (460 hp +/- 5%) at PR 2.7. The GTX2867R will exceed it's choke line (a.k.a. gas out) at 7250 RPM pushing 36 lb/min at a PR of 1.5.



Here's the GTX3076R compressor map under a 2.334L motor at various RPM's and Pressure Ratio's. At 3000 RPM the turbo's starting to get past the surge line (beginning to spool up). Turbo's full spooled at 3750RPM for Pressure Ratios 2.0 - 3.0. Limiting ourselves to PR's under 3.0 peak HP should hit about 6250 - 7000 RPM at PR from 3.0 to 2.7, pushing ~62 lb/min (625 hp +/- 5%). If limited to a PR's of 2.5 peak HP should hit about 7400 RPM, pushing ~61 lb/min (615 hp +/- 5%). If limited to a PR's of 2.0 peak HP should hit about 8400 RPM, pushing ~56 lb/min (565 hp +/- 5%)The GTX3076R will exceed it's choke line (a.k.a. gas out) at 8800 RPM pushing 46 lb/min (460 hp +/- 5%) at a PR of 1.6.



Here's the GTX3576R compressor map under a 2.334L motor at various RPM's and Pressure Ratio's. At 3000 RPM the turbo's starting to get past the surge line (beginning to spool up). Turbo's full spooled at 4000 RPM for Pressure Ratios 2.0 - 3.0. Limiting ourselves to PR's under 3.0 Peak HP should hit about 6400 - 7100 RPM at PR from 3.0 to 2.4, pushing ~62.5 lb/min (630 hp +/- 5%). The GTX3576R will exceed it's choke line (a.k.a. gas out) at 9,100 RPM pushing ~47.5 lb/min (480 hp +/- 5%) at a PR of 1.6.



Here's the GTX3582R compressor map under a 2.334L motor at various RPM's and Pressure Ratio's. At 3800 RPM the turbo's starting to get past the surge line (beginning to spool up). Turbo's full spooled at 4250 RPM for Pressure Ratios 2.0 - 3.0. Limiting ourselves to PR's under 3.0 Peak HP should hit about 7600 - 8300 RPM at PR from 3.0 to 2.7, pushing ~76 lb/min (765 hp +/- 5%). The GTX3582R will exceed it's choke line (a.k.a. gas out) at 10,500 RPM pushing ~62 lb/min (625 hp +/- 5%) at a PR of 1.75.

Overall:
The GTX2867R would seem to be an excellent 'street' turbo. Powerband running from 3000 to 7250 rpm. Boost would almost always be available for the duck and dart of street driving. You won't have to spin a 2.334 liter up to crazyville to use the whole thing.
The GTX3076R is more of the 'track day' turbo. Powerband running from 3750 to 8800 RPM. If caught out cruising in low RPM's you'll experience turbo lag. But if geared correctly, with head work to prevent the valves from floating, you'd have a track-day hero. But you've got to get those RPM's up to use it properly.
The GTX3582R is the 'drag' turbo. Powerband starting at 4250 and continuing up as high as you can spin it. I'm not even sure you could build a Subaru EJ 2.334 to take 10,500 RPM. But you can brag on the internet about how many hp's you' got on the dyno.

Keep in mind you could also adjust these by running larger or smaller A/R turbine housing, to shift the maps a bit.
* Registered users of the site do not see these ads.
68Cadillac is offline   Reply With Quote
Sponsored Links
* Registered users of the site do not see these ads.
Old 09-23-2014, 12:01 PM   #77
68Cadillac
Scooby Specialist
 
Member#: 95901
Join Date: Sep 2005
Default


Did the GTX3067R, and



GTX3071R just for comparison.
68Cadillac is offline   Reply With Quote
Old 09-23-2014, 12:05 PM   #78
68Cadillac
Scooby Specialist
 
Member#: 95901
Join Date: Sep 2005
Default

Ultimately decided on the BorgWarner EFR 7163 with Twinscroll and Internal Wastegate. It's perfect for my application.

Quote:
Originally Posted by subydude View Post
For the turbo, check out the comp maps for the EFR 6758 and 7153(sic). You'll like them more than the GTX series.

You're right. That EFR 7163 looks amazing on BorgWarners MatchBot Application. Thanks for the tip.
68Cadillac is offline   Reply With Quote
Old 10-08-2014, 05:15 PM   #79
68Cadillac
Scooby Specialist
 
Member#: 95901
Join Date: Sep 2005
Default

Happy day! I finally acquired all the parts for the rotating assembly to get balanced. Dropped it all off at the machine shop.

Crankshaft
Rods
Rod bearings
Pistons
Piston Rings
Wrist Pins
Timing gear/teeth
Flywheel
Pressure Plate
Bolts for the lot

Told 'em to balance it for up to 9300 RPM. That's the most it'll ever see, but a little more head room would be nice and bring peace of mind.
68Cadillac is offline   Reply With Quote
Old 03-11-2015, 04:56 PM   #80
68Cadillac
Scooby Specialist
 
Member#: 95901
Join Date: Sep 2005
Default

http://i.imgur.com/WRrYEqo.jpg
Getting ready to assemble the short block. Lots of cleaning and measuring going on.
Top piston rings gapped at .020" Per JE Pistons instructions for these pistons for this application.
2nd piston rings gapped at .022" once again per JE.
Rod bearing clearances measured (with bore gauges and micrometers accurate to .00005") to be .0012". Found the King XP (?) rod bearings to not have much variation between them. Only had to to do one swap of bearing sets from Rod 1 and 4 to get .0012" clearance on all. Otherwise it would have been .00115", .0012", .0012", .00125". (1 ---> 4).

http://i.imgur.com/cqlGWWo.jpg
Used a rod bolt stretch gauge to get the rod bolts on correctly. Probably the most critical fasteners to get correct in a high spinning motor. Glad I did too. My rods came with ARP's L19 Rod Bolts (Yes, I used gloves. Yes, I wiped 'em off with acetone. Yes, I coated them oil and lube). 3/8-24 thread. 1.6 inch grip length. ARP recommended that I install the bolts so that they stretched .0055" - .006". And even with ARP's special faster lube I found that each bolt needed varying amounts of torque to stretch properly. Two only needed 47.5 ft-lb. On two others I stopped using the torque wrench at 55 ft-lb and just tightened each one up ~ 15 degrees and remeasured until they stretched .006" exactly. I see why ARP recommends using stretch instead of torque to set these correct. 6 of my 8 rod bolts would have been under stretched if I had just gone by torque alone.
68Cadillac is offline   Reply With Quote
Old 03-11-2015, 05:05 PM   #81
bstuke
Scooby Newbie
 
Member#: 354575
Join Date: Apr 2013
Chapter/Region: South East
Location: Atlanta
Vehicle:
2013 818R
White

Default

Other than some minor issues I had a good outing at an SCR event at Michelin Proving Grounds in South Carolina.
https://youtu.be/7nxtmUJyN3U?list=UU...gLyDlo5iNxi1OA
bstuke is offline   Reply With Quote
Old 03-11-2015, 05:08 PM   #82
bstuke
Scooby Newbie
 
Member#: 354575
Join Date: Apr 2013
Chapter/Region: South East
Location: Atlanta
Vehicle:
2013 818R
White

Default

I highly recommend Cusco or Beatrush mounts. The engine moved around so much it broke the coolant tank on the frame brace. I put in Beatrush and they are awesome..
bstuke is offline   Reply With Quote
Old 03-11-2015, 05:12 PM   #83
68Cadillac
Scooby Specialist
 
Member#: 95901
Join Date: Sep 2005
Default

Quote:
Originally Posted by bstuke View Post
Other than some minor issues...
I love how you have the doors mounted. Got a link to more pictures of your doors?
68Cadillac is offline   Reply With Quote
Old 03-11-2015, 05:26 PM   #84
bstuke
Scooby Newbie
 
Member#: 354575
Join Date: Apr 2013
Chapter/Region: South East
Location: Atlanta
Vehicle:
2013 818R
White

Default

I'm hesitant to show you....

I 1/4 20 rivnut'd the bottom X 3 to the top of the side skirt. Then I drilled holes along the front and back and tie wrapped them to the frame with large black tie wraps.

I did this for two reasons. The first is I am going to trim 1.5" off the inside fronts to a line 0" on the inside back. This will give me another 1.5" between the fender and door instead of cutting out the door like others have. Secondly I need to get my intrusion panels(on their way) so I can trim the skirt and install the intrusion panels. Then I will do something more permanent.
bstuke is offline   Reply With Quote
Old 03-14-2015, 09:31 PM   #85
68Cadillac
Scooby Specialist
 
Member#: 95901
Join Date: Sep 2005
Default

http://i.imgur.com/1rMyeZi.jpg
Split the case again to install the main crankshaft bearings so I could get a bore gauge in there. Getting consistent readings on a bore gauge that's supposed to be accurate to 0.00005" takes a bit of effort for an amateur, like myself.

Did all this so I could calculate the mains' bearing clearances. Didn't want to trust plastigauge. Using bunches of measurements for the crankshaft and several for the main bore w/bearings my oil clearance are calculated to be:

#1 ---> .00165"
#2 ---> .0019"
#3 ---> .00165"
#4 ---> .0019"
#5 ---> .00165"

According to research done by King Bearings (click to nerd out), main Journal clearance for a 2.3625" diameter should be:

0.0012"--->0.0024" for a daily driver passenger car or
0.0018"--->0.0035" for a "High performance" car

So it looks like I'm running a little tight on 1, 3, & 5 for my high performance application. But well within the specs for a car. 1, 3, & 5 are also the bearings that feed the rod bearings oil.

Quoting from the above linked, King Bearing, white paper:

Quote:
Oil clearance
The basic geometrical parameter of an engine bearing is the oil clearance - the difference
between the inside diameter of the bearing installed in the housing and the diameter of
the journal (the inside bearing diameter is measured at 90° to the parting line).
Oil clearance should have an optimal value providing the desirable combination of the
lubrication parameters.
Higher oil clearance causes an increase of the oil flow passing through the bearing and
resulting in a lower oil temperature rise. However higher clearance produces less uniform
distribution of the oil pressure - greater peak pressure, which increases the probability of
the bearing material fatigue. Minimum oil film thickness decreases at higher pressure and
may cause direct metal-to-metal contact between the mating surfaces. Too much
clearance produces excessive vibration and noise.

Lower oil clearance results in a more uniform oil film pressure distribution and a greater
oil film thickness, however too small clearance causes overheating the oil and a sharp
drop of its viscosity.
High performance bearings produced by King Engine Bearings offer a wide selection of
undersizes so that is is easy to achieve the desired oil clearance.
Typical values of oil clearance C :
Passenger cars:
Cmin = 0.0005*D
Cmax = 0.001*D
High performance cars:
Cmin = 0.00075*D
Cmax = 0.0015*D
Where D = the journal diameter.
Bolding is my own.

So if I just run them as they sit the oil will tend to get hotter at a track day than one might like. But for AutoX, or driving to a show-n-shine I should be fine.
68Cadillac is offline   Reply With Quote
Old 03-15-2015, 02:54 PM   #86
68Cadillac
Scooby Specialist
 
Member#: 95901
Join Date: Sep 2005
Default

Upon a remeasuring I found out where I ****ed up.

http://i.imgur.com/3vxehfY.jpg

Bearings 2 & 4 don't have an obvious groove for oil in them like 1, 3, or 5 do. So the first time, I just measured the bore right in the middle of 2 & 4. Don't do that. 2 & 4 have a slight dish to them. The middle of the 2 & 4 bearings measure at 2.3644" while the edges of the same measure at 2.36405". A difference of 0.00035". So there's a slight valley in the middle of those two bearings, and I assume that's by design. You can't perceive it with the naked eye or by touch. It makes total sense to me that you've have a valley in there to distribute oil equally to the full circumference. By way of comparison, human hair varies from 0.00067" to 0.00709" diameter. So the valley in these bearings is less than half width of the thinnest human hair or about 9% the width of average human hair.

Remeasuring puts my main bearing clearances at:
#1 ---> .00165"
#2 ---> .00165"
#3 ---> .00165"
#4 ---> .00165"
#5 ---> .00165"

Accurate to .00005"

Damn. I didn't think they'd be so close. I have to give major props to Dale at Motion Machine and his superb machine work. Also to King Bearings for their excellent quality control. Wow.
68Cadillac is offline   Reply With Quote
Old 03-15-2015, 07:07 PM   #87
68Cadillac
Scooby Specialist
 
Member#: 95901
Join Date: Sep 2005
Default

Main bearing clearances sorted, time to put the short block together.

I'm building a long-rod, destroker using:
a 75mm crankshaft
+4 mm longer rods
piston wrist pin bores moved up +2 mm

Doing so requires one to do some goofy things to get the wrist pins in. You have to assemble it completely out of order from the FSM.

http://i.imgur.com/veXN3bQ.jpg
First you put the pistons in with the case halves separate.

http://i.imgur.com/nFT4atz.jpg
Second, set the crankshaft in the right case half. Rod bolts stretched proper and and ready to go. Place shims on the parting face. I used .125" (3mm) aluminium bar stock. You could probably get away with just using paper folded to 3 - 4 mm thick.

http://i.imgur.com/Hz0JiAI.jpg
Third, set the left case half on to your shims lining up your dowels. I temporarily, clamped the halves together. You could probably use just 2 case bolts to gently hold the assembly together (< 1 ft-lb of torque) You have to flip the case at least twice. Don't want those pretty mating surfaces dinging each other up. Don't want your spacers falling out.

http://i.imgur.com/8xWqAKB.jpg
Fourth, the "fun" part. Getting the wrist pins in and insuring the wrist pin c-clips are fully seated. I did them it in this order:
Piston 2
Flip case
Piston 1
Rotate crankshaft 180
Piston 3
Flip Case
Piston 4
Took me the better part of 2 hours, for just this step. Never let a mechanical part know you're in a hurry.

http://i.imgur.com/e6NUANb.jpg
Step Five, take picture. Continued tomorrow...

Last edited by 68Cadillac; 03-16-2015 at 01:27 AM.
68Cadillac is offline   Reply With Quote
Old 03-17-2015, 09:31 PM   #88
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: Milton Keynes, UK
Vehicle:
96 3MI Racing
search FIRST, then PM!!!

Default

Yeah, the first time I ever put together one of my destroked longrods, it took me a minute to get it all lined up haha
Homemade WRX is offline   Reply With Quote
Old 06-28-2015, 06:59 AM   #89
Kenward
Scooby Newbie
 
Member#: 297091
Join Date: Oct 2011
Location: AZ
Vehicle:
2012 STi Limited
DGM

Default

Sub'd again. Haha
Kenward is offline   Reply With Quote
Old 06-28-2015, 08:42 AM   #90
sidewayz
Scooby Specialist
 
Member#: 5810
Join Date: Apr 2001
Chapter/Region: Tri-State
Location: Easton PA
Vehicle:
2001 S366 2.5RS

Default

Why didn't you install the Pistons onto the rods, insert into the bore then tq the rods to the crank on the one half... Then put the other case on to do the other pins? Would have been zero flipping around involved.
sidewayz is offline   Reply With Quote
Old 07-30-2015, 04:56 PM   #91
Storm
Scooby Guru
 
Member#: 5218
Join Date: Mar 2001
Chapter/Region: MWSOC
Location: SAUL'S Motorsports
Vehicle:
96L Most Over-
Developed Beater

Default

Quote:
Originally Posted by sidewayz View Post
Why didn't you install the Pistons onto the rods, insert into the bore then tq the rods to the crank on the one half... Then put the other case on to do the other pins? Would have been zero flipping around involved.
There's a great reason why he didn't. Try it and you'll see.

Jay
Storm is offline   Reply With Quote
Old 10-15-2019, 07:56 AM   #92
shiftnmadkwik
Scooby Newbie
 
Member#: 83870
Join Date: Mar 2005
Vehicle:
2005 WRX
Black

Default

did you ever get it running?
shiftnmadkwik is offline   Reply With Quote
Old 10-29-2019, 04:13 PM   #93
MarkClow
Scooby Newbie
 
Member#: 25417
Join Date: Sep 2002
Default

I have an 818 and its a blast. However I just blew my diff and I am looking for a paid mechanic in ATL to help me with it.
MarkClow is offline   Reply With Quote
Old 10-29-2019, 10:00 PM   #94
subydude
Scooby Guru
 
Member#: 80649
Join Date: Jan 2005
Chapter/Region: South East
Location: Columbia, SC
Vehicle:
2000 2.5 Auto-X RSTi
Sparkly

Default

What transmission are you running? I have a spare 6 speed front diff sitting on the shelf I can part with.
subydude is offline   Reply With Quote
Old 10-30-2019, 02:50 PM   #95
Homemade WRX
Scooby Guru
 
Member#: 33782
Join Date: Mar 2003
Chapter/Region: MAIC
Location: Milton Keynes, UK
Vehicle:
96 3MI Racing
search FIRST, then PM!!!

Default

I have a Getrag from a Boxster S that I'm getting ready to sell.
See this thread for inspiration:
https://forums.nasioc.com/forums/sho....php?t=2047734
Homemade WRX is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

All times are GMT -4. The time now is 09:57 PM.


Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Powered by Searchlight © 2024 Axivo Inc.
Copyright ©1999 - 2019, North American Subaru Impreza Owners Club, Inc.

As an Amazon Associate I earn from qualifying purchases.

When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission
Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.