dc2696

iTrader: (2)

So I found the limit of the stock 1.6 transmission about 15minutes ago.

I was cruising at 110kph and rolled on the gas (made about 10psi) in fifth gear, tranny went BOOM!

I lost everything but forth gear, so I limped her home and have a job to do tomorrow now.

Not sure how much power I was makng but last night I accidently put the hurt on a R32 GTR with "upgraded turbs and 13psi" (no idea what else was done)

So anyway; stock 1.6 tranny ftl and I'm glad I didn't take it to the strip on my slicks, that would have been embrassasing :P


-Dean

magnamx-5

iTrader: (7)

good show man although i expect your tranny must have not been made very well still perfect excuse for a 6speed now imo.

dc2696

iTrader: (2)

I have a spare miata at home that's going to donate its tranny because I start school at the end of the month and 6 speeds up here are like 1500bux :S

I'l just turn the boost down I guess :(

pdexta

iTrader: (17)

What size turbo are you running? Any guesses on power? My tranny is about the only stock thing left on my '90 w/ 171k miles (~275k KM). I've been beating the **** out of mine at 260whp for about 5,000 miles now. Hopefully keeps on holding together, at least 5 speeds are cheap.

dc2696

iTrader: (2)

I'm running a fully built jdm 323 GTX 1.9l (built head minus cams,bottom end has wisecos and crowers, mbsp,balanced crank blablabla) custom SS mani, SS 3" dp, 2871, Mspnp, rx7 lsd, ported intake mani, and was creeping to 17psi. I'm guessing the power was somewhere under 300whp probably (no idea really) Only thn stock powertran wise is the ppf and trans.

The car would spin 1,2, and 3rd gear on 205/50/15 azenis.

Braineack

iTrader: (62)

now you can buy that TII trans that splitime is selling :P

m2cupcar

iTrader: (5)

That's crazy. It'd be worth it to try and freight one wouldn't it? I've seen them for $500- here's one that's close. It's been relisted several times.

Mazda Miata 6 speed transmission

Oh- and this one from Phil.

dc2696

iTrader: (2)

Thanks for the info M2, ony issue I have with the 6spd is I'll **** up my ratios unless I also find a 3.63 rearend.

Now I haven't found the ratios of the turbo II tranny to know what that will give me and I'm not to sure about removing the ppf and mounting the diff and trans to the chasis.

I'm going to wait and check things out because I'm going to be broke as **** soon so I don't want to splurge on something I don't need but I'm also going to be around 350whp when I turn the boost back up to 22psi so I need the strongest option (well between the two atleast)

m2cupcar

iTrader: (5)

Miata: 3.136 - 1.888 - 1.330 - 1.00 - .814
TII trans: 3.493 - 2.015 - 1.391 - 1.00 - .762

Pina06

...... I have been running 15+ psi for the last five years on my stock 1.6 tranny, never had an issue. At all.

dc2696

iTrader: (2)

15psi doesnt mean **** all(how much power doesn't your 15psi give you), I'm sitting close to 300whp and I beat the **** out of the car plus tracK it quite hard.

I've brken 6" rearends on stock 1.8 power so ya I drive my car a lot harder than most.

M2- **** those gears suck, thanks for the info again man

m2cupcar

iTrader: (5)

Pina- When looking at numbers, it's the torque that kills the trans.

Yes- ratios do suck. That's why I went for the 3.63 to go with the TII.

Pina06

not that i give a **** but who cares if youve broken diffs? who hasnt? You were talking about your tranny.

I could sit here and tell you what my cars has but that would just make you feel sad that i have a cooler car than you.

lets see.... my car is a 1990 (4 of 89) one of the first 300 in the US. So already its cooler than yours.

m2cupcar

iTrader: (5)

I think his point was that 1. the diff comment was to demonstrate how hard he beats on his car: hard enough to crack diffs with stock power and 2. 15psi of boost doesn't equate to "X" power level in all cases.

If you said your car made near 300 and never had a transmission problem, it would have been a relevant comparison IMO.

That said- there's a multitude of mechanical changes that also contribute to the trans failure - stiffer diff bushings, lsd, lsd type and condition, tire grip, stiffer pp, grippier clutch surface. And besides clutch dumping, just rolling into the power band in any gear other than fourth will be harder on the trans.

That said, my first 5 spd lasted about 2k miles and I didn't do anything but full throttle acceleration. OTOH I've had two friends track their boosted Miatas regularly (one with 260rwhp the other 300rwhp) and they never had 5spd trans failures.

dc2696

iTrader: (2)

Exactly. Just because your running 15psi on the smallest turbo ever made and make 180hp and haven't broken anything doesn't give you the grounds to directly compare our cars.

Mine has stiff bushings, stiff clutch, a motor that makes a lot of torque not to mention power and has been tracked to hell n the last few years. Yours for all I know is sunday driven and you have a stock clutch ect.

Anyways,

M2- So your running the turbo II with 3.63 gears? What's your speed in your first few gears like?

I thought first gear was already useless and the rx7 tranny is even shorter :P

How does the car feel without the pff? This is probably my major concern, I don't think it would be much dfferent and I was thinking of making a trans brace anyway (using it along with the ppf) because of the additional stress on the drivetrain now.

Thanks,


-Dean

jayc72

iTrader: (14)

Maybe some confusion would have been avoided if you hadn't been the one to first introduce boost into the discussion. Look at the title of the thread.

Get your car dynoed, then you can throw around actual numbers.

m2cupcar

iTrader: (5)

Plan was to run the 3.63 with the TII trans because that's the best I could do for the crappy trans ratios for a cheap solution. I was given two TII transmissions - one good, one needing a rebuild. My car was crushed before I got around to it, but it's still in the plan. I'm also bolting it up to something besides a B block. If I had a B block, I'd just go with the 6spd, it's easy and cheap (at least down here).

First gear is the biggest issue with the TII trans IMO. But that'd be a drag racing thing too. The parts I mentioned above combined with rough driving will break the trans for sure IMO.

dc2696

iTrader: (2)

See that's the other thing, I might be able to get the rx tranny for free, the adapter plate doesn't look to hard to fab up(based off mighty mouses thread), and the rest is just alignng the mounts for the trans and diff (driveshaft will need to be custom made though)

I can't remember anyone ever breaking the 6spd but I have a feeling that I'll be the first (that's a lot of $$ own the tube if that happens)

I'll be brainstorming for awhile and probably using my spare trans for the last few events this year, then do the swap this winter

Pina06

As you all know, i just joined this forum. And Im about to do something I dont like to do.

My car: Fully custom turbo kit (flipsidecustms.com /gallery/projects. The maita is mine) The engine in the pics IS a japan spec 1.6 (diff cams) from an automatic (lower comp) The only thing I have done to the engine is a FM head gasket and studs. Nothing more. I use a " Devils Own" Injection kit and I can run 17 psi with the T3 super 60 and link with all the goodies. I AM close to 300hp. Old engine, same turbo, -the injection and only running at 14 psi gave me 268rwhp. The car has so many upgrades there is too much to list. But here are a few. - Full RX7 Turbo 2 diff incl H/S and hubs that were re-cut for 4x100, custom drive shaft, Light F/W, coil overs, custom cro/mo roll bar, S/S 3" cat back, S/S 2.5" DP, wide band, knock, elec boost, 20"x12"x4" I.C. ----bla bla bla bla...

Anyone cane type a bunch of **** and lie thier *** off. I dont. And I know a few rl people in this forum that can back me up.

That said, the only thing on my car that has NEVER been touched is the stock tranny. For the last 9 years, it has been a rock soild performer.

*no time to spell chk*

jayc72

iTrader: (14)

Obviously mechanically empathy plays a big roll in how long an engine/tranny/diff will last. Clearly Dean has little of this empathy. Treating the car a little better might save some $$$. You can drive it hard and fast with out abusing it.