18psi

iTrader: (76)

those guys do 60-160 and 80-200 pulls. I can only imagine doing more than 130 in a miata hahahha better bring diapers

aidandj

iTrader: (5)

http://www.globalnetspace.com/miata.html

Ford or getrag with like a 3.23

sixshooter

iTrader: (12)

I hit 149.0mph on the front stretch at Daytona before having to stand on the brakes and turn into the infield. It was fine. It was pulling timing like a ****, but it was fine, lol.

#wrongmegasquirtsettings

18psi

iTrader: (76)

Isn't track a bit safer than a freeway though

sixshooter

iTrader: (12)

Definitely. And very, very wide in this case.

x_25

I will be curiously waiting to see how much the MSM rear can take. Gives me peace of mind.

patsmx5

iTrader: (16)

Can't wait to see. I got a spare diff and axles as well if it does break, if it breaks the diff I'll swap to spare and then probably do a ford setup down the road.

18psi

iTrader: (76)

Unless you have an auto, it's not apples/apples.

Though he did already have it hold up to what, 400? 500ish? on the 6sp so there's the comfort you wanted.

It's kinda similar with axles too: I see lots of manual guys on the other platforms exploding diffs and axles, yet the auto guys run real fast on the oem hardware. I think the limit of their torque capacity increases a ton when you take out driveline shock

patsmx5

iTrader: (16)

Yeah I maxed it at 40 psi on the manual, so around 500. It did ok, I think it will be fine with an auto for the reason you site.

patsmx5

iTrader: (16)

Haven't pulled the trigger on a glide yet, going to take some measurements and see if there's any way to put a 4L80 in the car.

codrus

Allison 1000?

--Ian

patsmx5

iTrader: (16)

For real.

The big problem with all the strong gm transmissions is RPM. The stronger they are, the less RPM they like.

Apparently the 4L60E fall apart with stock power all the time, even built ones break with 450-550hp LS motors. These are supposed to be shifted at 6,200 RPMs. Shift them at 7K and they fall apart very fast.

4L80's are a totally different design internally, heavier, but wayyy stronger. Basically a stock one with a shift kit would probably be strong enough for my car (about 750hp) but these shift at 5,200 RPMs. I know people run 4L80s in drag cars and fast stuff all the time though and spin them faster. Not sure how much they can take safely.

A1000 is even stronger, and shifts even lower.

I read on the 4L80's that at high RPMs in 1st gear, the 3rd gear pack will centrifugally start to apply 3rd. So, that bad and can toast 3rd gear. Not sure if this is a 1st gear problem only or in 2nd/4th as well. I think just 1st. Also if you rebuild the trans, you can drill a bleed hole in the 3rd gear pack to help bleed off the pressure from this. It helps, not sure if it fixes it 100% though.

sixshooter

iTrader: (12)

370 different gear ratios for her pleasure. Handles all the torques. A bellhousing already exists.
G-Force Transmissions and Long Shifters
G-Force Transmissions and Long Shifters

T101 / SR1 / GSR Transmission Gears | Tex Racing | side and top Loader | Andrews Products

Leafy

iTrader: (1)

Yeah really if you're considering the glide then the stupid 4 speeds are back in your ballpark.

Remember, the 4L80E is an updated and electrified TH400.

patsmx5

iTrader: (16)

Yeah, cost wise that's true. I think the 4L80E would be cheaper but not by a lot. But I also think the auto would be faster, and more consistent, and launch better.

I am doing some research right now on the 4L80E's dimensions to see how much bigger it is than the miata auto.

So far I got this: (measurements are inches over miata auto)

Bellhousing width, +2.7"
Total length, +0.26"
Pan width, +2.5"
The OD of the round "case" where all the gears/clutches are, this is 6.25" OD on miata, 7.50" on 4L80E so +1.25".
Overall width of trans including shifting linkages, lines, etc for everything behind the bellhousing, 10.875" on miata, 12.23" on 4L80E so +1.355"

So far it's looking possible. The bellhousing width is the worst. I think there's room to build an adapter and run the GM bellhousing, but that makes running 3" exhaust through that area probably impossible. I would loose half of the 2.7 on that side, so 1.35" less clearance than I have now, and with an auto I don't have much room there already. So best case would probably be a pie-cut 3" or pie cut 2.5" going through that area.

Or cut the bellhousing and weld the mazda one onto it. Lot of work for that, and then need a converter that is 9 3/4" or smaller, with a lockup clutch in it.

Big benefit to the 4L80E vs the glide is 4 forward gears vs 2, overdrive, and lockup converter. The lockup converter means I can run a high stall converter on the street, and it still locks up at cruise so I'm not spinning 4K+ on the highway. Overdrive is nice too, having no overdrive and no lockup with a high stall isn't as streetable as I would like! Also 4L80 is cheaper than a built glide, and more common and cheaper to upgrade.

Big downside is weight of the 4L80E, and getting it to fit. From what I know so far, I THINK it would fit as well as a glide. The glide's case is smaller in lenght by a lot, but the miata has plenty of room there. It's the bellhousing area that seems to be the problem, and the 4L80E appears to actually have a smaller housing vs the Glide in this area. (same bolt pattern, but different casting design behind the flange makes the 4L80E fit easier, it necks down sooner)

EDIT: Also the other big "downside" to the 4L80E is RPM. I can spin a built glide to 8,500, that ain't gonna happen with a 4L80 I don't think. At least not a cheap 4L80. But having more gears does help with that problem. Waiting to hear back from a semi-local trans builder about getting a 4L80E built for my setup.

codrus

They're also enormous and weigh about 300 pounds.

--Ian

TNTUBA

iTrader: (1)

Do you think a 2 speed glide would be the best choice though? I know several 4 digit HP cars that went away from the "glide" a few years ago and speed up a considerable amount.

patsmx5

iTrader: (16)

Honestly I have no idea. I have never ran one, or even drove/ridden in a car with one. Was mainly considering one as they are somewhat cheap, will hold power, light weight, and small enough I should be able to make it fit in the car.

I would love to have more gears, overdrive, lockup converter.

What trans did the several 4 digit HP cars you know go to?

If I knew a way to make the mazda 4 speed auto hold 600-650whp reliably I would do it in a heartbeat.

Leafy

iTrader: (1)

You could always do the glide and the gv overdrive and have a 4 speed.

patsmx5

iTrader: (16)

Yeah, but the GV overdrive thing is like 3K or so. My trans cost would be a 4 digit numbers starting with a 7 if I went that route! Maybe an 8...