818Rasmus E Modified

[xxguitarist]

Did you torque the bearing plate bolts (4) at the back of the transmission? You mentioned a few other bolts, but can't see if these are present. Otherwise, everything looks good!

[Rasmus]

Well it's totally counter intuitive but by torquing down all the bolts to the FSM's specs, including the 4 bolts on the 'back' near the shims, the backlash grew by 0.0025". It actually spaced out the pumpkin more. So I turned the backlash teeth another 1/2 tooth tighter each and:


got 0.0065". Might just go one more half turn on the right side and get it down to 0.0055".

THANKS BIGTIME HINDSIGHT! If I had just run it as it sat without adjusting backlash I would have been running super loose at 0.0110". Way out of spec.

[Rasmus]

Okay. I think I finally got this licked.


Tightened up the right side backlash 1/2 tooth more. Backlash down to 0.0055" with case torqued down. Within spec (0.0051"-0.0071").


Drive side tooth engagement pattern after the 1/2 tooth tightening with case torqued down to spec.


Coast side tooth engagement pattern after

Looks like tomorrow I get to button this guy up.

[Tamra]

The engagement pattern still looks strange to me, but the numbers shouldn't lie I would think. Perhaps the pattern is off because of the Dykem.

Which LSD did you go with?

[Scargo]

Looks good to me. Do you have the pre-load dialed in per the manual?

[Rasmus]

Looks good to me. Do you have the pre-load dialed in per the manual?

No. Should I be concerned about that? I only converted the output shaft to 2WD. I don't even own an inch-lb torque wrench.

Starting torque:
0.3 — 0.8 N ⋅ m (0.03 — 0.08 kgf-m, 0.2 — 0.6 ft-lb)

How does one measure 2.4 - 7.2 inch-lb and not have to invest in another expensive tool?

[MrDude_1]

No. Should I be concerned about that? I only converted the output shaft to 2WD. I don't even own an inch-lb torque wrench.

How does one measure 2.4 - 7.2 inch-lb and not have to invest in another expensive tool?

beam style torque wrenches are cheap.

[Boog]

Find something around that house/shop that weighs the right amount, say a .4 lbs hanging if your wrench is 12", and adjust until the perpendicular wrench just only droops with slightly more weight?
Free and probably accurate enough if you don't want to invest in a split beam.

[RM1SepEx]

harbor freight... 2.4 to 7.2 seems awfully low... are we talking about a plastic screw? my 1/4 drive has a low end of 20 inlbs I think!

[Scargo]

I have inch pound tools, but how about an electronic fish scale? I don't think mine was very expensive.

[Rasmus]

Find something around that house/shop that weighs the right amount, say a .4 lbs hanging if your wrench is 12", and adjust until the perpendicular wrench just only droops with slightly more weight

Interesting idea.

I think a wrench just free hanging by itself would be applying more torque than 7.2 inch-lb.

[Jaime]

I think he was talking about the preload on the side roller bearing that are loaded by turning the right adjuster in one notch beyond just touching. The bearing that you adjust the starting torque to 0.2-0.6 ft-lbs will never rotate with the 2WD coupler installed. It's between the pinion and the driven gears, which we lock together.

[Boog]

Interesting idea.

I think a wrench just free hanging by itself would be applying more torque than 7.2 inch-lb.

I suppose you would have to add in 50% the weight of your wrench to start with.

I think he was talking about the preload on the side roller bearing that are loaded by turning the right adjuster in one notch beyond just touching. The bearing that you adjust the starting torque to 0.2-0.6 ft-lbs will never rotate with the 2WD coupler installed. It's between the pinion and the driven gears, which we lock together.

I like this idea better.

[Scargo]

Yes, that preload:
13) Turn in the retainer on the upper side additionally by one notch in order to apply preload on taper roller bearing.

This is after the "zeroing" which seems rather arbitrary and to be just by feel... and is up to you to decide what zero is. Don't forget to beat on it with the hammer. That's in the manual, too.

[MrDude_1]

Don't forget to beat on it with the hammer. That's in the manual, too.

tumblr_mir5phFyBq1qfjej5o1_r1_500.gif

[RM1SepEx]

tumblr_mir5phFyBq1qfjej5o1_r1_500.gif

classic!

[Scargo]

With you obsessive, anorexic car modding behavior, why have you not removed the center upper steel that runs between the seats? I see no need for it. Anything that is home there can be covered with aluminum sheet and that attached to the steel below. I think one person has done this.

[MrDude_1]

With you obsessive, anorexic car modding behavior, why have you not removed the center upper steel that runs between the seats? I see no need for it. Anything that is home there can be covered with aluminum sheet and that attached to the steel below. I think one person has done this.

The tunnel bars are a load bearing part of the chassis design. It adds torsional stiffness.

[RM1SepEx]

The tunnel bars are a load bearing part of the chassis design. It adds torsional stiffness.

nope, can't be they just "float"

[Scargo]

They are not even "boxed in" on each end. Might add some flexural resistance, front to rear, but I doubt it's needed at all given the stiff box (around the passengers) that's already there in an R.

[Rasmus]

With you obsessive, anorexic car modding behavior, why have you not removed the center upper steel that runs between the seats?

I need to figure out how I'm gonna mount the shifter. We'll see if the bars stay or go, once I get that sorted.

I have have to disagree with the Dude. I don't think the 'tunnel' bars add any significant rigidity to an 818 chassis. They've got two 90 degree joints that are welded together. They aren't even braced off or triangulated with anything.

[MrDude_1]

I must be thinking of the wrong bars. Anyone have a picture?

[Rasmus]

Need to add the speedo gear to this boss on the right side of the transmission case. If I don't my ECU will put my car in limp mode.


So I bought a bunch of small parts from Subaru. Two cost around $75 a piece. So even with my discount this lump of parts cost over $200. =(

Install order:
Speedo Sensor = 85082AE000
Seal = 806712100
upper snap ring = 805012020
washer = 803012060
Shaft = 32713AA002
Transmission Case
Gear = 32714AA190
lower snap ring = 031512000

This little, plastic, 30 tooth, gear cost $80.


But everything installed easy.

[Rasmus]

Transmission getting ready to go back together.


Dribbled "Smurf's Blood" on everything (Red Line 58404 Lightweight Shockproof Gear Oil) and made double sure the two front bearings on the both shafts were sitting correctly on their pins so the case wouldn't crack when I torque it back together.


Now this was supposed to be the picture where I show you guys my transmission all put back together and ready for install. But as I was cleaning up I found this part I failed to put back in. It and it's not like it's a little tiny screw or something. The FSM calls it the "Main Shaft Rear Plate" and it's huge. It's hilarious I forget to put it back in.

[Hindsight]

Hahahah good thing you caught it now! Nice work on the transmission. Seems like installing the diff is a little more complicated than I had thought it would be. Not too bad though.

[xxguitarist]

Oops! At least you don't have to split the case halves for it!

[Frank818]

Rasmus, did you go to the F1 GP in Austin this w-e? Might be a couple of interesting lightweight ideas over there.

[Rasmus]

Nope. Watched it on TV. Coverage on NBC was commercial-riffic!

[Mechie3]

I don't think those bars add much stiffness. They're in the center of the car so if it's twisting front to back it's right on the axis of twist. The closer to the axis the less stiffness it provides. They're narrow, thin walled, and can be flexed apart by hand.

[JeromeS13]

It looks like Factory Five removed them from their latest R project:

DSC_30981-694x413.jpg

[longislandwrx]

Nope. Watched it on TV. Coverage on NBC was commercial-riffic!

At least during commercials you could kind of see what was happening on the left. Even on a 55" inch TV the video was pretty small.

A good race though... If Rosberg had shaved off his amazing hair, he probably would have had those 2 seconds.

[Hindsight]

You ok Rasmus? Over a month since your last post. Hope all is well and the build is coming along.

[Rasmus]

Oooo boy do I have issues. Personal life aside...


Opened the trans back up and installed the input shaft thrust plate I forgot to put in there the first time 'round.


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).


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 in 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 fastener 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.

[STiPWRD]

He's back!

[Tamra]

Welcome back!!!!

[Scargo]

Holy guacamole Batman! Now I have another thing to do... I found this about tightening rod bolts, like you are doing. Since I may go to 9K, I best pay attention! Thanks...

While you were AWOL I assumed your role as "master lightner". I hate to bring this up, but with my DOM steel tubing, front LCAs, I will knock off three pounds per side over the aluminum STi LCAs I have. Of course it took using straws to accomplish it.
It's great to have you back. Your insight is invaluable. Next time do not vacation for so long without notice. We started to worry.

[metalmaker12]

You don't do that and boom! Good tip

[Mitch Wright]

Welcome back

[Hindsight]

Great to have you back Rasmus!

[metros]

I've been wondering about your build for awhile. Glad to see you back at it.

For those of us not in the know, why is it so important to glove up, acetone, and re-oil the L19 bolts?