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Discussion Starter #1
The engine is getting closer to the project truck. It is time for me to really get into motor mount fab. My concern now is which would be best tilted the motor or transmission. I am using the GM adapter with the 400 turbo transmission. The P-30 tilted the motor 10 degrees. When I put the motor in my truck should I put it straight up which would put the transmission at a 10 degree tilt or should I mount it like the P-30 and tilt the motor and let the transmission level? I could split the difference and put them at opposing 5 degree tilts.
The pros and cons. The motor looks better straight up. If the motor is tilted it gives more master cylinder clearance and puts the turbo outlet a little closer to the bottom of the firewall.
What do you think??:confused:
 

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tilt the motor

I think it's better to keep the tranny level. I'm mounting my engine in with the tilt, it gives me more clearance with the steering box, front axle, and in my application, the battery. I know it really comes down to looks...I was uneasy with the tilt idea but it actually will work better for me. Besides, I don't drive around with my hood open.:)
Hopefully a transmission expert will give us some insight here on how well the tranny would function tilting to one side for the rest of it's life. If you checked the fluid level it would always read low, then you might over-fill it and too much oil is a bad thing. We've all driven on rough, un-even terrain and I've driven on bigger slopes than 10 degrees and my tranny shifted fine, I guess I wasn't going too fast though. I am just not sure about it ALWAYS leaning to one side. Jed
 

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In a 4WD vehicle with an attached transfercase as you rotate the engine 10 degrees you roll the transfer case a tremendous amount....that would have to be addressed. An automatic transmission would be better to be level or to split the difference if a 2WD truck. Please click one of the Quick Reply icons in the posts above to activate Quick Reply.
 

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Discussion Starter #6 (Edited)
Level it is for the tranny. 10 degree tilt for the motor. I'm glad I just tack welded the final parts of my motor mounts for the block. I probably should knock it apart and build the tilt into the engine side of the mounts. That was 2 days work for nothing.
I had a 45 degree mounting pad on each side of the motor. The block is machined for a straight vertical mounting. If the motor is tilted 10 degrees then the right side should have a 35 degree mounting pad and the left side should have a 55 degree mounting pad. The frame gets 45 degree mounting pads.
 

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I run my engine level. It didn't fit in the engine bay at a tilt. I have a friend that did a 6bt 4l80e in a burb in 98. He tilted the trans t-case. He has almost 100K with no problems.
 

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Discussion Starter #8
I have finally got the engine on the hoist and hanging in the engine bay.
The bottom is going be tight. I don't know if I am going to be able to clear the a/c. I'm working with a mid 80s GM truck frame. For a while I thought I would be able to just set the Dodge mounts right on the stock GM motor mount plates. Then I thought, "How am I going to tighten the bottom bolt?" The stock GM mount plates are actually a little high. I haven't cut the 45 angle plates off the motor mounts yet. I was going to make sure I had a workable setup first. It looks a lot better with the engine sitting straight up. The 10' tilt makes thing worse on the passanger side brackets. The a/c will require frame surgury for sure with the 10' tilt. It looks like the master cylinder would clear even with the motor straight up. My custom built water inlet points right at the top of the frame rail. I will have to make another with a 10 to 15 degree angle built in. I had put the water temp switch hole in the front. The belt tensoner bracket I made doesn't allow that to work. It also looks like the lower radiator hose will have to go out the inner fender panel and then come back in the engine bay at the front. Just when I thought I was making progress I find I have to start most of the work over. As long as I learn from my mistakes I guess it is still progress.
 

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Discussion Starter #9
If you checked the fluid level it would always read low, then you might over-fill it and too much oil is a bad thing.
It leans the other way. It would read high when properly filled if the engine was vertical. Somehow it would have to be determined what the proper fill was and remark the stick.
It isn't harmfull to overfill an automatic transmission. If it is to way overfull it will just push it out the vent. It makes a mess but doesn't cause any damage.
I had a 700R4 I was trying to nurse to a repair spot. It acted like it was low on fluid. I had an aftermarket fill stick in it that was nearly inpossible to read. I wound up adding a quart of fluid. I did that 3 times (3 qt overfill). It came out the vent and sprayed everything. My diagnosis was partly correct. It acted like it was low on fluid but the filter was totally plugged. When I would stop fluid would run from the transmission body and backflush the filter. When I would dirve it would pick up the toasted converter clutch in the pan and plug the filter again. The transmission was taken apart and everything cleaned. There was no damage (went less than 10 miles with the problem). Replaced the converter and it was good to go.
 

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Thats funny, when you guys were talking about 10* tilt I assumed front to rear.Must have just done side to side on just autos, the two Chevy sticks I have the motor is tilted high front to low rear guy fleet guy said all the Chevys are like that. The Ford sticks are parallel with the frame.ASS U ME!
 

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Discussion Starter #11
Thats funny, when you guys were talking about 10* tilt I assumed front to rear.Must have just done side to side on just autos, the two Chevy sticks I have the motor is tilted high front to low rear guy fleet guy said all the Chevys are like that. The Ford sticks are parallel with the frame.ASS U ME!
Yep the Chevy auto setup has the top of the motor leaning to the passanger side by 10 deg. I cut my motor mounts up and added a 10 degree tilt to them today. There isn't any time to play with them tonight or tomorrow night.
 

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It leans the other way. It would read high when properly filled if the engine was vertical.
:confused:
Are you sure about that?
When I sit in my truck, the motor tilts to the passenger side and the tranny is level. So if I were to rotate the motor to the driver side, thus leveling it in the truck, the tranny would lean to the left, opposite the dip stick.
TH400 and 700r4 both fill on the passenger side so I am I wrong here or what?

Jed
 

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Discussion Starter #13
Sometimes my mind is a little tilted and it doesn't think clearly.
Your right.
 
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