Oooh. I like that spread sheet. Can I have a copy?

Aren't the T2 diffs notorious for breaking, at least way more often than T1's? If so, putting a unicorn gear in a weak diff doesn't sound smart...

No. TF diffs are notorious for breaking. T1 and T2 are the same strength.

Then what is the issue to where T1 diffs are preferred? I vaguely remember something about an internal spring on the T2's being the issue?

They behave slightly differently under braking and Accel. It's a driving characteristic difference not issue with one or the other.

Driving the Miata to my Dad's place tonight, going to pull the valve cover off to see about the noise I've been having. After seeing Aidan's issues with his lifters, I'll be checking those, gauging the lifter clearances and overall looking for unusual wear. I'll try to post pics later tonight/

Pulled the VC off and found.... NOTHING. No problems in the top end whatsoever, gaps on 4 of the valve pairs were all below .01 for gaps. I did find a thread that mentioned the grommets between the heater core hoses and the firewall can wear out, and one does move more than the other and there's a hose clamp that I COULD see tapping against the other clamp or the brass against the firewall.. I believe I'm going to replace the valve cover gasket and try driving it again, if I get the buzz I'll ziptie the hoses together to see if that resolves it. Seems to go away with heat when the engine gets hot, so I was thinking bearings buuuut.. the hoses get softer with heat too, which could make it change the vibration pitch? IDK. Will know more tonight.

Got things cleaned up, lost a fairly big rtv chunk into the oil passages. Ran a gallon of mineral spirits through the engine to clear anything out. Poured oil over the cams. Rtv applied and valve cover on, just needs to cure now.

https://cimg8.ibsrv.net/gimg/www.mia...603d05be7f.jpg
https://cimg2.ibsrv.net/gimg/www.mia...351c59a572.jpg
https://cimg6.ibsrv.net/gimg/www.mia...a944a88ad4.jpg

Below .01"? Exhaust should be .111-.133"

I thought the difference in 'strength' was caused by the acceleration and deceleration bias of the respective units. I thought autocross folks preferred the T1's due to driving characteristics, but the T2's were less likely to go kablooey during a launch since they're decel biased.

Source? The construction of the T1 and T2 are very similar. The TF is a totally different diff.

Yeah, I'm not referring to the tofu diffs at all.

Torsen Diff - Spec Miata Garage - Mazda Racers

"Type 2 is a fundamentally more robust design". Don't have an 'official' source for that, but perhaps there was confusion with the T2R unit which was a specialized version of the T2. It's also funny that torsen has a faq saying that the NA/NB torsens are no longer being made as they were last made in 2002 and all the tooling is gone lol.

You didn't finish the quote.

"The Type II is a fundamentally more robust design, but I have not heard of either unit breaking from track use. They seem to last forever."

That still wouldn't negate the fact that its stronger, if that were true. In any event, the issue is the diff case, not the torsen itself right?

Not the case, the gears inside the torsen shatter when they break, then pieces of those gears get into the ring and pinion and destroy that too.

Except for the MSM diff right? I've heard there was a guy that could break anything he set his mind to breaking and he couldn't figure out how to nuke that!

Something like that! I break a few things from time to time in the name of go fast.

You're right, that was entered in a frenzy. Intake was definitely tighter than exhaust and exhaust was above .1.

I'm picking the car up tonight, gonna throw some zipties in the car and see if I can get the buzz to happen.

Precisely why I was looking at a OSG if those 3.3 gears ever ACTUALLY re-materialize. I don't want to spend the $ on 3.6 if the 3.3 are actually happening.....

Noise still extremely prominent between 3250 and 4k, dad's thinking it might be the downpipe (crack/fracture somewhere?), he's getting a lot of noise and vibration off the turbo from the stethoscope and was thinking maybe it was that. Spool and turbo characteristics were OK as of a few days ago (well after the noise started) so I'm leaning to a downpipe crack resulting in harsh harmonics after the turbo and the plywood undertray is acting as a reflector. Is there an easy way to dump exhaust up off the manifold if I pull the turbo off to test the car? Hmmm...

I still have my TSE downpipe so perhaps I'll be giving that a go? Fighting a cold, might be a while before I get to this :(

Good news! Found the (extremely likely) source of the buzzing noise, the downpipe has a (very hard to see) crack where the bracket to the transmission was attached. I figured this might be where it would be cracked but it was stuffed up behind the exhaust blanket so I couldn't see it before. Upon taking off the blanket I noted that it had ate all of the gasses from the cracked pipe which would have been blowing on the transmission otherwise. Bonus I suppose, definitely proves it does it's job. I'm going to call the exhaust shop tomorrow and see what he thinks about putting in the TSE downpipe and mating their exhaust to it. Probably have them fix the crack while they're at it, maybe I can sell the thing. Definitely needs a flex pipe if the securing bracket stays.

Bad news! We pulled Lacey's car apart to put in her radio, but while driving my Dad's Saturn to the apt to get her parts we smacked a deer full bore at 60-70mph in what I can only say was nature saying "FSCK YOU!" and took my happy moment and kicked me square in the balls. We've been having a lot of rain in MN lately and the grasses along the freeway are quite tall, the deer must of crossed the far side at a quick pace and maintained it as it came out of the median at a run, barely missed the car in the passing lane and we smacked it with my dad's Saturn on the driver's headlight/hood area and went right over the car. It might be repairable, there were no leaks or noises but I really haven't had the constitution to go look at it today.

Car was repaired, the noise is gone. Exhaust shop didn't quite do what I asked though, and they welded the lower section of the DP to the existing exhaust instead of cut the exhaust to length and weld a flange there like I asked so I don't have to fight the slip union and can swap exhausts anytime I want. Now the DP is heavily impacted for any potential for resale..... Le sigh~

While out and about I hit some big bumps while slideways and the (well secured and tied down..) battery slid and (barely) brushed the + terminal cable against the tie-down strap which shorted the power out. I have no idea how the terminal moved, but my guess is the shop had to pull it while working or something because I didn't have it like that before... Not sure what that that did yet, but the car has hesitation and misfiring, thinking maybe Cam/Crank sensor but I need to log it. Trying to stay positive but... Always something, eh? :(

Ran some logs today, definitely seeing a stumble under load (low load is fine). Random, but appears to go along with throttle or maybe I'm imagining it. It's DEFINITELY ignition related, it feels almost exactly like when my CAS/CrAS was having issues. Logs show the RPM shifts up/down some but otherwise I don't have anything in the log to indicate what might be causing it. Probably my steps to diagnose will be the following;

-Check plugs, maybe I have wear and I'm blowing out spark?
-Swap out coils if I can find the spares
-Check timing w/ light
-If I can find some to do so, swap TPS, CrAS, CAS in that order.

Note that the car ran fine after I left the shop all the way until the battery came loose which I've ensured will NOT happen again. Go figure the replacement from last year was smaller in form than my old one which precipitated this whole PITA.

Update on the Saturn, we stripped the body down to examine the radiator core and it looks like he deer buckled at the bottom of it's torso, the hood caved and rolled back creating a 'ramp' that shot the deer up and clear of the car. If I had braked, it would have buried the nose and probably bounced off the windshield or the roof. As it sits after pulling out the damage, we just need a hood/fender/bumper/some brackets and the headlights. Didn't get any pics before we pulled out the damage but I'm going to swing by tomorrow and snap a few for the memories.

Standard procedure to disconnect the battery when welding on a car. You can fry a bunch of electronics if you don't. So at least they got that part right...

After a long week of 'F-it' I returned to looking into this issue. Figuring maybe a bad plug or two I pulled and replaced spark plugs (1/4-1/2" browning at the base of the ceramic), didn't really do much and the car still ran like crap with breakup showing up at low-load mid-high rpm range. I gave up for a while and went about my evening and after hanging with Lacey to get my mind off the issue I figured hey let's try logging at 48samp/sec since I have my bag w/ the laptop with me. While I was in there I figured I would clear LTT (long term (fuel) trim) but checked it first because it's been a while (last fall).

WOW. Huge plateau of +50 cells all over, especially in boost. Thinking "Like, wtf?", after clearing LTT I logged some driving and found I could not reproduce the heavy misfire issue anymore and LTT was adding fuel again. This could be a coincidence as it doesn't ALWAYS do it but there was at least some hesitation before, but my theory is that it hit the upper threshold on the trim map and started having issues when it wanted to add more fuel to the +50 cells which AFAIK it can't. Grabbed some food and when I got to the apt I looked at the display and noted that my AFR value wasn't moving anymore. It appears my wideband is not working- Thing has less than 5k / 11 months on it, holy shit. I wasn't really looking at it as I have not had the laptop on hand, so I'm hoping the exhaust shop guy left it unplugged..? How does the Hydra display a dead Wideband? I'm guessing a static AFR value...

For now, I cleared the LTT data and disabled fuel LTT. I'll take the car out tomorrow and see how she drives after having a night to cool off and sit.

Anyone know the pinout for the hydra wideband? The exhaust guy pushed the pins out of the harness and the wires don't match the ecu side of the harness......

Found a pinout in P9 of the new FM instructions. After wiring things back together the car runs flawlessly. Yeah!

Man, talk about a long day of discovery. I attached some images to show what I encountered for the o2 sensor causing misfire. Pic #1 shows the harness and the wiring clips after I removed them from the harness - They were already pushed out of the securing tab part of the connector but still mostly inside of it so luckily they didn't contact one another and short or anything. Pic #2 shows what the shop did with my flexpipe lower section for the TSE pipe- welded it directly to the exhaust. I actually asked for a flange here so I didn't have to mess with the slip union... I will bring this up on Monday as I need a time to cool down (next post). Pic #3 shows the o2 sensor at an angle, which pulled the harness cable tight and during big bumps and turns, pulled the wires out of the connector.

Tonight we finished up the fuel pump hardwire and WOW, look at pic #4. I have no idea how this happened as I never dug this deep into the harness here, but the wiring sheathes were either rubbed through or chewed through or IDK, but both black leads were exposed as well as the Red/Blue +12 wire (!!!) - I am so extremely glad this did not end in a fiery disaster at some point. I crimped and soldered spade connectors on the factory wiring as well as the rewire in case I need to revert (knowing my luck I would fail to start after all this crap). Testing had her start on the first try, hooray! Burned the shit out of my right pinkie though, swole up like a mofo. Hoping it doesn't rupture :cry:

Lastly, we have this (#5) delicious Pork Roast cooking in the slow cooker at home and will be digging in shortly.

Look at this disaster, this is the consequences of my o2 sensor not registering and the LTT of the Hydra continuing to adjust fueling. Not sure how much damage was done, but you can definitely see aluminum in the ceramic as well as the electrode. Not sure how I will approach this with the exhaust shop, if I even CAN hold them accountable...

Glad I caught this somewhat early on. :-|

Pic #4 looks like what I found in a friends car caused by mice.

Why on earth is your ECU tuned to rely on a functioning oxygen sensor? That's not your shop's fault, that's your tuner's fault. O2 sensors fail all the time, you cannot rely on them for normal operation. The ECU should run the engine in perpetuity safely in the absence of a functioning oxygen sensor (and more to the point, it should do that in the presence of a malfunctioning oxygen sensor).

You know, it surprised me as well. You would think if it failed or in this case was DISCONNECTED it would stop the LTT function. Just a bad implementation...

Fun times. I bled the clutch fluid and refilled it twice to give it a good flush since the fluid was pretty grey and also adjusted the rod to move the engagement point down some. I noted there was a little preload on the rod (holding pressure on the master cyl) but only JUST. Maybe 3/32" or less still feel like it's engaging higher than usual in travel though. Clutch hasn't even been in a year but I -DO- daily drive on it including some traffic but I try to avoid that. Maybe it's just how these organic twins wear, plus all the POWAH I'm running though it..

One thing I have noted since last year is that I lose clutch fluid. Not always and it's inconsistent, but I have run almost dry once and have lost a 1/4" periodically between checking. Could the fluid in the lines be boiling? I haven't seen any leaks anywhere so it's a mystery right now. Maybe the MC?

Organic twins wear very fast. I did 8k on mine and it was probably over 2/3rds done.

Well that could answer things then, could be it's just wearing out.. that would kill my budget for racing for the year though. Blargh. We don't have many options for 350+ torque either, I will probably get the new organics and the upgrade since this I'm sure is definitely pre-2015 stuff as it's the old organic discs..

How was your wear on the flywheel by the way? I know the organics are supposed to be less hard on it than the ceramic so I'm wondering how frequently I need to replace that as well.

Seemed fine I will probably be upgraded to the Kevlar discs if I don't go BMW transmission

Saved for future thread.

Good to hear. I just hope the flywheel lasts a few clutch swaps which it sounds like it will.

I've been looking at the 949 hybrid mount kit, my car is already pretty loud so any increase in NVH probably isn't going to be too bad. Even with the MR angled shifter, poly diff bushings and mazdacomp bushings I still think I have too much deflection during cornering/shifting. Hopefully these will help.

https://cimg6.ibsrv.net/gimg/www.mia...d789d8fd45.jpg

Yeah! Replacement twin-disc and upgrade kit delivered, I'll be pulling the car in the garage and starting work tonight.

I'm also thinking of swapping my stock 1.8l brake parts to the following setup, anyone with brake experience able to chime in on what I should expect?

- 01-05 sport booster (NON-abs) -- I guess this has a slightly bigger diaphragm (15/16 vs 7/8) for more brake boost
- TSE 11.75" BBK (dynalite most likely)
- 01-05 Sport rear brackets, stock 1.8l calipers and 10.9" rotors

Not sure on pads yet, maybe Hawk HP+ in the front and HPS or HP+ in the rear? I'd probably swap for Carbotech XP8 all around after testing the setup on and killing these pads.

On my way to the garage to start working.. I put my sport brake parts in the car in anticipation of upgrading things. I just need to confirm before I buy anything, are these the rear brake brackets I need to use after removing the sport calipers to swap my NA brakes to the sport 10.9" rotors if I want to keep my NA calipers/pads in the back? For whatever reason I feel like I am missing something.

Clutch is on and torqued, found that the two long bolts that go through the starter were both loose so I torqued them after a drop of locktite on each. Think I'll have it done tonight.. At least I sure hope so, the twin can be a bitch to align to the input shaft..

https://cimg3.ibsrv.net/gimg/www.mia...ce81637015.jpgClutch installed. Sport brake setup in the tote.

https://cimg5.ibsrv.net/gimg/www.mia...64e9f8f779.jpgLeft the stud alone as it was only damaged above the nut and functions fine so I'm leaving it alone after tightening it and a little locktite.

https://cimg8.ibsrv.net/gimg/www.mia...4dee95fc4e.jpgThe floaters got replaced by new ones. They definitely get hot in street driving with all the shifting. Hopefully the thicker plates will maintain a little better.

https://cimg1.ibsrv.net/gimg/www.mia...cc0ca92eae.jpgDiscs appear to have life left, did i over react? Pedal was markedly moved up and the engagement was feeling like it was close to slipping.

Long night, after a night at the ball game we headed to the garage and I finished buttoning things up. Having issues with the fuel line not sealing on one AN fitting right before the rail and the heater core hose connectors are once again slow leaking. Trying to figure out the best solution for the heater core issue, maybe a thin layer of RTV would seal things? It's definitely slightly warped and needs some massaging in the future. Almost want to make those two hoses 2-part so there's less likelihood of leaks in the future.

Fuel lines needed just a tad more torque to stop a weep after sitting for a bit. Also rotated the fittings on the heater core bung and tightened them down, appears to be sealing and holding after temps hit 210. Babied it home last night and after driving around today with it in the 90s with no leaks I think she's good to go. Adjusted the rod in some to get a little bit of free play; so far this new carbon/kevlar clutch 949 has for the twin engages like butter, almost no shudder at all. I think it will be very easy to DD.

How is it compared to the organics

Honestly, it feels like I'm driving my Saturn the engagement is so painless. The organics I stalled the car a LOT getting it going when I first put things together. I didn't experience this at all. I keep thinking something's off, but then it holds WOT without slipping so it must just be awesome then lol

Awesome!

Today we tackled the passenger footwell subwoofer project that has been stalled for a while now. I had planned to have a (experienced) glass layer friend over to help kill a few cases of beer and to both make this go smoothly and make sure the end product is better than what a rather inexperienced glass can do. In the end however, the expiration date on the resin can was the deciding factor and Lacey and I decided to tackle it this weekend while the weather was nice.

We began by taping off the entire area to be glassed as well as some extra to provide position options after removing the shell. I laid a alternating 3 layer criss-cross of masking tape and then (didn't take a picture) laid strips of aluminum foil over that. Once this was all done, I draped some foil over the carpet by the door and the door bar and I laid 2 layers of mat and we left for the night. I'll update with more tomorrow.

Shell cured overnight, trimmed and removed the foil and tape. So far looks good, need to figure out how I will build the boxes volume as the woofer requires .5-.65³ft of volume, perhaps along the tunnel in a tall, narrow void? Or along the toe board ? Bearing in mind I have to keep it removable, I'm trying to keep it above the glove compartment's reinforcement brace. Not sure. Any suggestions appreciated, I'll probably try to start working out the remainder of the parts like a pair of MDF rings to countersink the subwoofer tomorrow.

This is pretty much what I am going to try and setup today, need to pickup a hot glue gun and some packing peanuts and cut those rings now.

https://cimg0.ibsrv.net/gimg/www.mia...f90ca9ec22.jpg

This is going to look good when completed. With the weight being in the corner, it may be a good idea to secure it somewhere to prevent any movement.

The 10 just wont fit, .5³ft is just asking too much to have any leftover legroom and keep it removable with the door bar there. We opted to go with a more conservative 8" JL which calls for .3³ft and will look a lot more like the image above. The 10 is going in my DD.

In other news, I got a thing! I'll be installing these, the prop valve, sport rear calipers and sport MC early next week once I have my pads for the rears on hand.

Today was very productive! I had an interview and accepted a position at a new job. More IT stuff, but in a larger setting with actual benefits so I don't pay for Dr visits out of pocket.

To celebrate, I got drunk and messed around with the sub shell again tonight. First images show the speaker ring after the glue set overnight, the cardboard is measured to the biggest 8" sub I would consider putting in there which should leave ~5" of clearance. I attached a baffle to help solidify the box and give it some form. I had removed all of the foil and tape from the shell that I could but some of it persisted so I used a cup wheel to further scuff up the shell and clean up the remaining foil and tape. In the process, a few bubbles were removed to be re-filled with resin to prevent compromising rigidity.

I then cut some mat to the desired shape and removed it, and cut 3 more sheets. In total this will make 5 layers of some high density marine fiberglass mat. I added some foil and taped it on to build up the sides a little and laid all 4 layers of mat. Afterward, I cleaned up any air bubbles I found during curing by popping them with a razor and working them out. Resin tended to pull the mat back on once I worked it a little.

A few hours in, and as I was laying the last sheet Lacey showed up and I semi-assisted while she replaced her radiator which had a crack in the plastic endcap. After around 4 hours the resin was STILL somewhat soft, the temps dropped from the low 80s to 67f so I brought out a space heater and put it on the shell. I'll be damned if within half an hour the shell was ~80*f and most of it was ready for further work. I sat a cut up box over the top to close in the heat and it was fully cured by the time we finished her car and left (3am..).

I'm going to bed. More work tomorrow unless BLARGH IM DED.

Further progress on the box; Saturday I attached the ring to the shell after trimming to suit and glued in some MDF stands. All said and done, the ring was wedged in pretty securely before applying any resin. I then scuffed up the ring and baffle to give them a good mechanical grip and then stretched a 100% polyester pillowcase over the box and cut to suit, gluing it in place. Once things were positioned properly I test-fit things and all is looking good. I did find that the box will get close to the glove compartment hinge and brace with the carpet in place however without it it will clear fine. I will likely either trim the brace if it will work or I will cut the carpet to add clearance. With the brace in place though, the box will not come out of the footwell which is some added security. I tested the interior volume and found it is a little too big, perhaps .4³ft but I need to reinforce it yet which should cut down on volume a little (and some extra volume can help make subs sound better).

Sunday I cut fiberglass cloth (3 sheets) and mat (2 sheets) to size and put a permanent marker dot on them so I could position them when I lay the layers. I then placed my first two coats of resin on the cloth and lip of the shell that it contacted and then cut ~25% with acetone on all wood contact surfaces to ensure it got good penetration along with mechanical grip and added all 3 layers of cloth and 2 layers of mat and reinforced any weak spots with an extra piece and trimmed the overlap off. Today I will cut things flush and reinforce from the inside the union of the shells and the ring as well. Also thinking of a 4" wide strip around the overlap area on the outside.

Tonight we trimmed off the lip around where the edges meet, I then hit up the box with the cup wheel again and cleaned up any rough surface defects and gave a nice scuffing around the edges. Due to humidity we held off on any resin work tonight. More work tomorrow.

Today, I sanded the front facing surface with 80-grit. Once I was satisfied with how it ended up, I applied liberal amounts of the messiest incarnation of fiberglass I've used yet, Bondo Glass which is supposed to be similar / the same as duraglas. It has fiberglass strands mixed into a paste that you mix with a hardener and apply within 3-4 minutes of mixing. I used it to seal the interior of the box to the outer ring as well as further seat the 'legs' of the ring to the base of the box and the ring. I then applied a single layer of cloth to cover the front and overlap into the base by roughly 2" and applied resin. Once cured, I trimmed the opening and applied a layer of paste around the ring/glass transition, allowed it to cure, sanded and applied resin. Tomorrow I will sand things down, drill a hole and install the wiring and speaker.

In other news, the cooler fan for the Saturn died today while driving to the fingerprinting appointment for my new job. Luckily I have a spare on hand.

Today I cleaned up the inside of the box as there were some loose bits of bondo glass and other stuff floating about in there. I then drilled a barely-too-small wiring hole and hot glued it after heating the fiberglass/wiring some (much like soldering) to ensure glue penetrated. Pulled the knot tight and glued over that and the exterior holes. Installed the sub and test-fit in the car, installation was fairly painless and found I only required a small trim to the glove compartment mount bracket to clearance the ring in one area. Just need to look into proper carpet to match the black interior now..

Today I tested the sub with my spare amp and confirmed it held up to rigorous abuse. I then pulled the sub, taped off the opening to the box and painted the rings black to match the carpet and sub; this turned out better than I expected TBH. I found some carpet locally and once the ring was dry I applied some Super77 to the box and the carpet and got things laid down and used adhesive remover to clean up any overspray. I'm frankly surprised at how well it turned out considering I've never used it before.

Today I mounted the sub into the box, and then into the car. Added in the glove box and bracket and put a small piece of hose in as a gasket to keep the brace from rubbing into the carpet. Turns out the brace will act pretty well as a support and keeps things from moving. Since I had a spare channel left in my amp after one burned out a while back I figured I would wire in the box with a quick disconnect and connected it to the spare channel. It's not nearly enough power to really drive it, but at least it's there. It'll be a little while before I can get a reliable and compact amp. Next on my plate is swapping brakes.