250 WHP Supernatural 3.4 Build (Page 18/47)
La fiera DEC 17, 06:37 PM



Got my injectors and fuel pump a couple of weeks ago and did some bench tuning to the Mega Squirt. Eager to drive it since two weeks ago today is the perfect day to go for a ride and fine tune the software to the new injectors and pump upgrade. The engine feels very strong!! Leaving my driveway sideways and trying to avoid the mailbox on my way out I went up the hill controlling a four wheel drift, the best feeling ever!! I tamed the beast and kept driving on third gear while turning on "Auto Tune" on the MegaSquirt so it can do its thing and get me close to where the car should be.
I get to a light and stopped. Light turns green and I gently hit the throttle and the sticky Toyos light up and the car goes sideways, shift to second and its still sideways!! I let off and hit the throttle again to keep the car in a straight line and is all good when I noticed a wining sound, like if I had straight cut gears! I got to a gas station and look underneath and see oil pouring out my trans.
Drove it home and the wining noise was very loud while in gear, in neutral there was no noise. I made it home fine. I jacked the car up and and saw this long crack on the trans housing!! I just laught!!

Anybody selling an M19? Does anyone knows of somebody who makes straight cut gears for this tranny?
Patrick DEC 17, 06:49 PM

Ouch!
Blacktree DEC 17, 08:20 PM
The weak point on the 4-speed Muncie is the outer casing. Other gearboxes (like the HM282, F23, etc) have reinforcing ribs on the outer casing. I'd suggest upgrading to a later HM282 ('93 and up with the stronger differential housing) or the F23.
Will DEC 17, 09:40 PM
Second driveline component you've blown up in a month... I would call this the MOAB of clue bombs.
pmbrunelle DEC 17, 09:57 PM
You need the Muncie M17 (85-86 V6) gearbox case. M17 cases have ribs cast into the case to make it stronger than the M19 case.

Inside the case, you may use whatever* combination of M17 and M19 shafts/gears you like.

*Not all combinations of gears/shafts are possible. When you have the parts laid out in front of you, the allowable parts combinations will be easy to see.

The input shaft, output shaft, and differential are all supported by tapered roller bearings at each end. Axial preload is fine-tuned by a shim on the outer race.

Once you have chosen your parts, use the J-26935 tool (available on ebay) to help you choose the correct shim to preload the bearings correctly.
La fiera DEC 17, 10:34 PM

quote
Originally posted by pmbrunelle:

You need the Muncie M17 (85-86 V6) gearbox case. M17 cases have ribs cast into the case to make it stronger than the M19 case.

Inside the case, you may use whatever* combination of M17 and M19 shafts/gears you like.

*Not all combinations of gears/shafts are possible. When you have the parts laid out in front of you, the allowable parts combinations will be easy to see.

The input shaft, output shaft, and differential are all supported by tapered roller bearings at each end. Axial preload is fine-tuned by a shim on the outer race.

Once you have chosen your parts, use the J-26935 tool (available on ebay) to help you choose the correct shim to preload the bearings correctly.



Thanks for the info! I have the original M17 trans here. I'll take the M19 out an see what I can salvage out of it. Thanks again!!
La fiera DEC 18, 07:15 AM
OK, got my hands on a F23. What else do I need? I saw some kind of adapter on the mall (Thelin) What is that for?
Shifter, mounts and cables, where do I get them?

Thanks
mender DEC 18, 11:39 AM
This might help:
F23 swap

[This message has been edited by mender (edited 12-18-2017).]

La fiera DEC 18, 08:07 PM
After doing some research and reading about the F23 I decided not to do it. If somebody made a kit to drop the F23 in flawlessly I'd do it but that is not the case.
To keep things simple I decided to take PMbrunelle advice on swapping cases from the stronger M19, I already ordedred the shim tool to do it.
The bad thing is that I thought I had an M17 but what I have is a MY8 because the case is smooth just like the one in the M19. I say is a MY8 because of I remember 4th gear being VERY tall compared to what I have now. So now I'm looking for a M17 trans, anybody has one?
Will DEC 18, 10:00 PM

quote
Originally posted by La fiera:


Thanks for the info! I have the original M17 trans here. I'll take the M19 out an see what I can salvage out of it. Thanks again!!



You said you'd swapped in the 4.10 gears, but I didn't realize you swapped the entire transmission. I would have cautioned you about that.

Use the V6 first & second, as the first is taller and second is stronger than the 4 cylinder gears. IIRC, both boxes have the same 3rd & 4th ratios, although due to detail differences in assembly, those have to stay with their respective output shafts.

I've built a 3.32 V6/Econo Muncie, so I've been inside a couple of those gearboxes before. They're stunningly, even ingeniously, simple.