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Blocked a piece of vac tubing and blocked off the bov and I still wasn't making boost. Swapped the piece over to the EWG... and all of a sudden I hit boost cutoff. So it looks like the issue is with the ewg. Go figure...
Update 1: It was the external wastegate. Applied a gob of grease to the inside on a rec to help it seal a bit better and it did the trick. That was the only modification made and it worked totally fine afterwards.
Update 2: Bytevenom came by last week to help me pull the 4.3 torsen out since I'm swapping a 3.9 in. We got to dropping the diff and stopped there and I did the rest myself. I ran into lots of issues along the way. What issues? Well...
I thought the hardest part was going to be knocking out the old diff bushings. That wasn't too bad...
They knocked out pretty easily. The issue was getting the new bushings in. I didn't buy delrin or poly because I didn't want to get diff whine. So I bought the goodwin mazda comp equivalent bushings. They seemed pretty good. Well... after watching all the videos of folks putting in poly bushings, I figured the installation was the easy part without realizing that rubber bushings were a totally different animal.
So I tried to hammer them in.... that didn't work so well. So I tried a 3 jaw puller. Which led to this happening:
I was a bit worried that I'd ruined the bushing by stretching it so much but it seemed fine. Crossing my fingers on that.
I gave up on the 3 jaw puller idea pretty quickly since it wasn't doing anything and I didn't want to damage the housing. I made a trip to an autozone outside of town and picked this up.
If you're doing this at home and don't have a press, I highly recommend using this with a breaker bar. It made it so freaking easy to get the bushings in! Look at all the attachments! A few are the perfect size to fit right around the housing so you don't damage it.
In my mini drunkenness on saturday night while working on things, I decided to paint the diff. It turned out alright. Why drunk rtc decided it would be a good idea to paint something that isn't visible? I have no idea...
And then it went back in without too much trouble. My rear brakes don't have the metal retaining clips and of course the pads moved on me so that was a pain in the *** to fix. I adjust the parking brake mechanism as well and it looks like I have a small fluid leak coming from the drivers side in the hole for the parking brake adjustment allen head. Looks like I'll need to keep an eye on it and rebuild/replace if it starts leaking any more.
Got a chance to drive for a few minutes after getting things done and didn't hear any weird noises. The shifter moves noticeably less and the shifting feel is way more crisp. I think this was the right decision for me over poly, but I kinda wish I'd just bought the poly bushings because of how big of a pain in the nads it was to get the 'comp' bushings in.
Car's been running well for the little bit it's been driven lately. I'm starting to plan out what all I want to do over the winter... So far a motor build looks likely with a BE stage 2 pump, 949 crank damper, 36-2 wheel, etc. Still having a hard time deciding between going for a rods build or just doing pistons too 'while Im in there'. Rods should let me max out this turbo but if I do the pistons and want bigger turbo in a year, I won't regret it. I'll have to see if my budget can accommodate being stretched enough for pistons and motor work. I have a 6 speed on standby, but really like having the 3.9 with the 5 speed, so that would make going over the rods build 'threshold' a bad idea if I want to keep that going.
Planning to swap in nb2 headlights as well and hoping I can find a bumper or just live with the 'gap' till I do. If that works well, I can probably recoup a little money from the headlights as well.
I really need to sell my torsen and the BE stage 1 pump to help make things a bit more favorable. Anyone looking for those?
This is the craziest coincidence ever! Just yesterday my pal Dee was like "hey, do you know anyone selling a Torsen and a BE stage 1 pump?"
Then I read this and I was like, "holy ****"! He's gonna be so happy.
This is the craziest coincidence ever! Just yesterday my pal Dee was like "hey, do you know anyone selling a Torsen and a BE stage 1 pump?"
Then I read this and I was like, "holy ****"! He's gonna be so happy.
Hey @aidandj, hope things are going well with you! Thanks for stopping by man.
Would you mind elaborating a bit though? Are you saying that drive-ability etc start to suffer past that point?
It's stops being a Miata. You gotta make sure you are in a straight line before stomping on the gas.
Spinning tires at 4500rpm in 4th gear is scary.
Your clean underwear budget will be bigger than your gas budget
Yeah... This is one thing I've thought about since I like to be able to daily this car a bit. I can always have a 'rain map' or something. I am running boost by throttle right now which is pretty glorious. I went for a late night back road run last night and I'm honestly so happy with how well the car is running right now. Theoretically, I could still up the boost another 1-2 psi since I'm at 200rwtq according to VD. Should get it to ~220rwtq, but what's the point.
Originally Posted by sixshooter
I don't have this problem. What tires and rear camber? Mine stays hooked and goes.
What are you at again now? Like 330ish right? Are you running TPS based boost with MS3? You're also on a pretty big turbo right? So your power hits a bit later on. I remember seeing you post in the spool thread but that was atleast a year ago if not longer.
I don't have this problem. What tires and rear camber? Mine stays hooked and goes.
It depends on a lot of things. Mine makes 340 at the wheels, and will sometimes hook in 2nd (warm RRs on a dry track), and sometimes spin in 5th (cold Rivals on a wet, bumpy road).
As far as keeping underwear clean, TPS-based boost targets help a lot, as does putting in a switch on the "tableswitch" input so you can select between two different boost levels and pick one for conditions. RaceLogic TC is the ultimate.
I know this is probably going to be laughed at... but that won't be a first so...
If one was to do a rods only build, what could be reused if pistons were to be added in the future? I know you'd have to open everything up again, but lets say I only had like 10-20k miles on the block after the rebuild, could I reuse bearings/head gasket/etc? From what I've read.... I'll go with no. Doing pistons would mean going with ACL head/main studs as well and that may be a good time to do that as well if it's being punted into the future. Though I'm better someone has done it and been fine. I think @patsmx5 has haha. I've also seen folks just pull the pan and swap to forged rods and have everything work fine. I think @pdexta did that but said he got lucky as well.
From folks I've asked that know a lot more about this than I do, it seems like folks put the stock pistons at like 280-300 rwtq for limits, so that would make getting to 300rwhp a possibility. I'd likely get a honda manifold from @KasbeKZ to go that route, but I'm 100% sure I'd come up well short of that with the current turbo. Savington got about 300hp out of his 6758 build on CA91, so I'm guessing that trying to go above that with 93 would be challenging and asking for trouble all the same. There's no E85 around me at all and 91-93 seems to be the norm on trips I take.
I also realize that I need to pay attention to cooling. I have a reroute waiting to go in when the engine is pulled and i bought sixshooters old oil cooler setup as well that will go on with a thermostat plate. I have a feeling I'll also need bigger fans and I've been eyeing the FM setup in the classifieds and have been mulling over just listening to savington when he wrote that a single 13inch spal fan is a solid option as well.
That said, I know that @aidandj loves his powahhh so if he recommends restraint, I know there's a good reason for it. I'm cognizant that a driver mod is in need too.
I pretty much have all the parts sitting to do a rods build (ACL bearings, eagle rods, sealed power rings, BE stage 2 pump, 949 damper, etc). I'll either pull my motor or use a friends block that's being pulled shortly. I can add more parts as I sell a few things or just front the money and make it back later.
Originally Posted by Steve Dallas
In for the inevitable "RTC runs out of talent" post...
Oh, come on. You know me better than that. I would hope that a mod would have changed the thread title by now!
One of the reasons I want to build up another block is that I can hold onto mine if, i.e. when, that happens!
Originally Posted by aidandj
Its not a problem with 225 R7s, but 225 RS3s cause issues. Isn't your car also a track car?
Just sharing my experiences. My motor makes 380hp at full tilt, but I drive at 280 90% of the time.
This is good to know. You beat my post, but that's why I had a feeling that you had a good reason for it.
I just bought back the 15x9 advantis that I had sold off earlier. Rivals still have some life in them, but I have a feeling that I'll be running them just about all the time if I decide to keep them. Can sell the twist wheels with all seasons for tire money or just keep them for DD duty to save the expensive rubbah.
My goal here is to learn to build a block and do valve stem seals and springs in the head. I'm not trying to reinvent the wheel. I let thirdgen give me a hard time because I bugged the **** out of him when I first got his setup, but he's helped me a lot and I've come a long way in understanding a lot of this stuff.... while also not flunking out of med school haha.
Thanks again for all your help. I appreciate the wisdom from folks that know far more than I do.
Pretty sure I've already said this, but whatever. You need a clear defined goal, then pick your parts accordingly. It's that simple. If you want something that can do 350whp on a track with high reliability, get good forged pistons as they are much stronger at high temps. If it's a street car and you want it stone reliable, again, do forged pistons as they are more suited for the goal of reliability. If you're on a budget and only want 300-350whp on a street car, stock pistons can do that, but I would highly highly highly (very imporant) recommend running E85 as it keeps the temps down, and cast pistons loose their strength when they get hot where forged pistons can run at those temps and not loose much strength. That's the reason forged pistons are good for high power, they keep their strength at temp. E85 and a conservative tune helps keep temps down, which is good for stock piston builds. Pick a goal, then picking parts is straightforward.
If one was to do a rods only build, what could be reused if pistons were to be added in the future? I know you'd have to open everything up again, but lets say I only had like 10-20k miles on the block after the rebuild, could I reuse bearings/head gasket/etc? From what I've read.... I'll go with no. Doing pistons would mean going with ACL head/main studs as well and that may be a good time to do that as well if it's being punted into the future. Though I'm better someone has done it and been fine. I think @patsmx5 has haha. I've also seen folks just pull the pan and swap to forged rods and have everything work fine. I think @pdexta did that but said he got lucky as well.
Reusing a head gasket is like reusing a condom. Don't go there.
Replacing pistons means boring & honing the block, so it means tearing it all the way down to a bare block. I guess you could reuse the rod & main bearings at that point (assuming they were in good shape, no work was required on the crank, and the block didn't need line boring), but it doesn't sound like a great idea to me.
You can't pull pistons out the bottom of the motor because there's stuff in the way, and even if you could you wouldn't be able to compress the rings properly to reinstall them. Since the wrist pin won't come out with the piston in the cylinder, this means that there's no way to change rods without pulling the head off.
Far and away the best approach is to figure out where you want to be, assemble the budget for it, and then go there in one step. Doing it incrementally isn't much different from doing it over.
In addition to the heat resistance of forged pistons, one additional benefit to doing pistons is that you get to pick a new compression ratio.
Pretty sure I've already said this, but whatever. You need a clear defined goal, then pick your parts accordingly. It's that simple. If you want something that can do 350whp on a track with high reliability, get good forged pistons as they are much stronger at high temps. If it's a street car and you want it stone reliable, again, do forged pistons as they are more suited for the goal of reliability. If you're on a budget and only want 300-350whp on a street car, stock pistons can do that, but I would highly highly highly (very imporant) recommend running E85 as it keeps the temps down, and cast pistons loose their strength when they get hot where forged pistons can run at those temps and not loose much strength. That's the reason forged pistons are good for high power, they keep their strength at temp. E85 and a conservative tune helps keep temps down, which is good for stock piston builds. Pick a goal, then picking parts is straightforward.
This is definitely true.
My goal with this entire build was to learn to do things. The goal here is to learn to build a motor... I guess that's a bit *** backwards in this application because goals determine parts etc. To fulfill 'build a motor' goals, I could just refresh a stock block and call it good when it runs.
We don't have E85 here, so it's definitely something to consider if I have any plans of going over 300, i.e. forged pistons being very strongly suggested.
Originally Posted by codrus
Reusing a head gasket is like reusing a condom. Don't go there.
Replacing pistons means boring & honing the block, so it means tearing it all the way down to a bare block. I guess you could reuse the rod & main bearings at that point (assuming they were in good shape, no work was required on the crank, and the block didn't need line boring), but it doesn't sound like a great idea to me.
You can't pull pistons out the bottom of the motor because there's stuff in the way, and even if you could you wouldn't be able to compress the rings properly to reinstall them. Since the wrist pin won't come out with the piston in the cylinder, this means that there's no way to change rods without pulling the head off.
Far and away the best approach is to figure out where you want to be, assemble the budget for it, and then go there in one step. Doing it incrementally isn't much different from doing it over.
In addition to the heat resistance of forged pistons, one additional benefit to doing pistons is that you get to pick a new compression ratio.
--Ian
Hah, fair point. I guess the issue, as I suggested above and as Pat was getting at, is that I don't have a power goal in mind. I'm waiting for @Colipto to get his car driveable so I can get a ride along in a 300hp+ car... that much power in a miata just sounds scary fast. Aidan saying that he basically runs his car at 280 90% of the time is a pretty big tell. That's about 60hp/tq over what I'm at now, which isn't insignificant at all. I'm sure it could handle slightly more power in a DD setting vs a autocross/track setting, so I could always do the dyno queen thing to see what it would do and run it on a lower map. I do think that something 2871 sized would probably be best though, especially from the standpoint of heat since there's no way this turbo's going to be happy with that much boost.
I have the budget and parts to do the rods and machine work (if necessary). I can budget pistons, but I'd feel kinda dumb doing it if I'm never going to utilize it. Regarding your comment about swapping compression ratios, I'm planning to move down to NA8 pistons just for a tiny bit more det resistance on pump 93. I probably wouldn't modify my tune for it at all, but it'd just give me some headroom in case I have to run 91 or get some shitty 93.
From what I'm seeing, it really doesn't seem that too many folks are running built blocks (rods+pistons) much higher than 300 without E85. Is that accurate? I almost daily this car in nicer weather, but I usually end up driving my subaru if it's stupid hot out especially if I'm expecting to hit a bunch of stop and go traffic because the AC in the miata isn't as good and I've had issues with overheating in the past, which is why I'm doing a few cooling mods over the winter.
11-08-2017, 03:22 PM
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