patsmx5

iTrader: (16)

Well in the past I rev'd high with stock bearings, raced more than I did with this motor, and never had bearing wear like this. It wasn't a big deal before, but it is now. I jut ordered a set of stock mazda bearings, going to see how those do.

patsmx5

iTrader: (16)

Thanks! It does work too, rear turbo lights off at least 2K RPM faster than before.

DNMakinson

iTrader: (3)

Is that a twin scroll turbine? Or does your system work by doubling the flow speed? What is the valve you used?

sonofthehill

iTrader: (1)

Sorry to hear about your setback, hopefully the new bearings will get you through the season. I might have a crank I'd be willing to part with if you decide you need one.

patsmx5

iTrader: (16)

It's a T4, 1.05 A/R divided turbine. I used a 44mm wastegate for a valve.

Thanks. I think the new bearings will help a lot, maybe even fix it. The crank isn't perfect, but it's not that bad either. If the bearing swap doesn't work out, I may be contacting you about that crank!

sonofthehill

iTrader: (1)

Let me know, I actually have 3 good ones, not counting the one in my car. I only have 2 extra usable blocks, so there's an extra crank.

18psi

iTrader: (76)

Very clever, and that's a huge improvement in spool

sonofthehill

iTrader: (1)

He's very sharp!

patsmx5

iTrader: (16)

Will do, I'll message you about that in a bit.


I've always wanted to do a quick spool valve on a twin scroll. I almost did it years ago when I had the garrett GT3271, I actually bought all the material, designed a valve, and then never built it. To be honest, I was googling to see if anyone ever used a wastegate as a valve for a quick spool valve, and after enough searching I finally did find someone who did essentally the same thing I did, so I did it. It did make quite a difference.



So, update....

It runs! New bearings are in and so far, it's looking good.


I will hopefully drive it tomorrow and put some miles on it, and go from there. No catastrophic failure as of yet, but it only ran a few minutes so far mostly idling. I have some pics I'll post hopefully tomorrow. It was faster to do a vid and upload it than to take pics and type out info about them. Maybe I should do vids more often.

patsmx5

iTrader: (16)

Ok so... When the car was taken apart to do bearings, I had a vibration in the engine when I rev it. But, I also had a separate vibration that got bad at 40mph, and extremely bad by 60, to the point I pulled off the highway to slow down. Since I paid 240 bucks to have a custom driveshaft made and BALANCED I figured that's probably what is wrong. I have never actually had a driveshaft made before by someone else that didn't shake, well, this was no exception! I picked the car up, put it in 3rd at idle, and got under the car and LOL the driveshaft shakes like crazy. I put a dial indicator on it, it showed 37 thousands of runout on the front, 26 on the rear! And to top it all off, not a balancing weight on it. After being really pissed about dropping this much money on a POS, I called the place that made it and took my money, and they said they don't have a balancer, they just use a dial indicator in a lathe to balance it. They offered to rebalance it. Yeah, so they screwed it up once, didn't balance it, and are offering to do the same thing again to "fix" it. I hung up and called another shop, and they claim they have a 100k dollar balancing machine and that he would be willing to show me the machine and the paperwork on it showing that it was very recently calibrated. So, I get to drop another 200+ on Monday for another custom driveshaft. This was the one thing on the drivetrain I decided to not DIY, and it's not going well.

Oh yeah, it gets worse. So the shaky driveshaft trashed the rear bushing on the tail housing of the transmission, so now I gotta pull a ton of crap, drain trans, pull tail housing off, and press out/press in a new bushing. Gasket, seals, bushing all ordered, and I'll have to buy fluid. So yeah, fix one thing, and then a lying POS shop took my money, and sold me a crap part that damaged my transmission.

On the up side, motor seems to be doing ok so that is good. I also beaded my intercooler pipes as I have had two pop off in the last year. So that shouldn't happen anymore.

ridethecliche

iTrader: (2)

Gahhhhh!
That's so frustrating. Hope the new shop does right by you.

Ryan_G

iTrader: (8)

So it will be done and running on Monday?

x_25

You can DIY balance a driveshaft by spinning it up, holding a sharpy to it until it just contacts to find the high side, then putting hose clamps with the heavy part opposite the high side. Don't even have to take it out of the car.

Note, I have not tried this myself, but learned about it from some old hot rodders.

patsmx5

iTrader: (16)

Thanks! Me too.
The parts for the trans won't be here till Tuesday I was told. So probably Tuesday at the soonest.

I actually made my own driveshaft before this one (it had <5 thou runout and I made it using hand tools) and I did balance it the way you describe and it seemed to work well. I paid a shop this time as I was trying to do it right/do it better. If the next shop also does a bad job, I'll be making my own again.

sonofthehill

iTrader: (1)

patsmx5

iTrader: (16)

Small update, trans was taken apart, repaired, and put back together. This was kind of a pain, I screwed up the new bushing on the install and had to cut it out and buy another and try again, but second one looks good. Tomorrow I'm bringing my driveshaft to get fixed and actually balanced.

TurboTim

iTrader: (9)

Been there on the driveshaft fiasco. Mine was 'balanced' by V8R when I bought it (no weights), went to the local guy, then do a place that does KB Racing's Prostock cars/our bonneville truck's shafts, until I ultimately spend a few hours doing it myself with some hose clamps.

Be sure your pinion angles are right first though.

Like everything else, if you want it done right, do it yourself.

sonofthehill

iTrader: (1)

So true

patsmx5

iTrader: (16)

This shaft was way out of balance. But I will recheck the pinion and tailshaft angles just to be sure they are right. It's at shop #2 now, they claim they will redo it and it will be right. If not, yeah i'm doing it myself.

patsmx5

iTrader: (16)

So I dropped off the driveshaft today at shop #2. I called later this evening after not hearing back, and they told me they can't fix it and are having to remake the driveshaft. I showed them some wrinkles in the tubing at one of the weld yokes, and I thought that was from the "heat balance" BS that shop 1 claimed to do. Well, they said that wasn't what caused it. Well they got it apart, and shop #2 says that shop #1 took a .065 weld yoke, ground on it with a grinder, and then hammered it into a .083 wall thickness 3" tube. That explains the retarded level of runout, vibration, and wrinkling in the tubing. WTF shop #1????

Anyways so will be getting a completely new driveshaft now. They showed me their two balancing machines and some paperwork from a recently balanced driveshaft they did with it. So it does appear they can balance it. No idea what the cost is going to be now that they are building a new one, not repairing the old one... So that sucks. But oh well, hopefully they do a dang good job and I don't have any more problems with it.

Also I don't think I mentioned it, but back in like 2012 or 2013, I bought a cheap ebay catchcan (one that was hollow) and put some baffling in it but never installed it. Then a year or two ago I took it apart, redid the media inside it to some less-fine material, reassembled, and then still didn't install it. Since I had bearing problems lately, I figured I should put it on since having the PCV system going will keep the oil happier with miles vs no PCV. Haven't drove the car with it yet, but it should work and that's one more little thing to help keep the oil happy to help out the new bearings.