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Discussion Starter · #1 ·
I'm working on my mounts, for those of you who've used the P30 liquids, do they compress much with the engine weight on them? Also, any problem with these engines on a slight tilt front to back? I've got the tranny bolted to the original support and with the front bottom corners of the block about 1/2" from the cross member I have maybe a 1" drop from the front valve cover to the rear one. I can space the tranny mount up if necessary but would like to keep original location for sake of the U- joints. This is a 90 F150, I'm using the mid-engine mount pads, looks like the passenger side will be a challenge with the starter. Thanks.:)

Steve
 

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Discussion Starter · #2 ·
Cmon, anyone have their 4BT on a slight front to back slant? I don't think it'd be a problem but would like to hear from someone who may have done the same.
 

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Steve;
To establish proper drive line angles on my Carryall and M37, My engine, nv-4500 and married NP-205 sit at a 7 degree down angle (at the rear).

Paul
 

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Well, I've not taken out of the bread van yet, nor have I taken the weight off the mounts to tell about the compression factor.

But.. Looking at it, it appears to be in the compartment at an angle already, front to rear, with the front high, in addition to the 10* tilt to the right (passenger side). I'll have to grab the measuring stick and look when I get home. (What, a good excuse to play with the Cummins? Oh, and might have to move it to a spot better suited to measurement, so I get to hear it run? Aw, geez...)

The way I've always approached engine orientation in a swap is this: When are you EVER going to be driving on a completely level road? While you do want to set up the swap as level / square / etc as you can, slight variation probably won't matter too much in operation. Cummins had to take into account the extremes the vehicle may be operated within, most especially steep hills (up, down, and across). Never mind what some of the rock crawler types are putting them through.

Paul mentions the thing that I'd be more concerned with... Driveline angles. Unless you're running a CV shaft, if you get the pinion and output shaft out of parallel by too much, you're gonna have vibration and eat U joints.
 

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The liquid isolaters will squish a bit not enough to worry about 1/2 to 3/4'' .

The tilt of the engine needs to fit to your needs ,every conversion unless the same will require different mods.

CrewCab59
 

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There is a lot of information on the "Show off ur motor mounts" post.
The following is a portion from page 5 of that post. I wrote,

"I can't believe how much softer the rubber mounts are since they are drilled. I built the frame part of the mounts with the rubber mounts installed before I drilled them. I thought I was putting the engine in for keeps tonight. NOT. The softer mounts allowed the motor to drop another 1/4". I was already slightly tighter than I wanted. Now there is deffinately not enough clearance between the pan and steering arm/crossmember. I have to take it all out again and modify something. I may try to add a 3/8 shim between the rubber mounts and the engine part of the mount. It looks like the stud is long enough to allow that. I had to cut up a box end wrench and modify it to install the nut for the drivers side bottom stud on the mount."

These were the 1st series Dodge mounts that I was refering to not the P-30 mounts. 1/2" is pretty tight when you consider how much the motor may sag the mounts and then factor in the shake. It would be easier to give yourself more room now than later after the pan has a hole rubbed into it. My P-30 had a hole repaired in the pan when I bought it. That is talked about in another post here.

I do have my motor higher in the front than the rear also. I did add a shim under my transmission mount to eliminage part of it. I don't remember how much it is, but it is easily visible. This is typical for all vehicles. If you look at some of the intake manifolds on the gassers you can see that the carburetor plate is mounted on an angle compared to the plane of the intake runners. This was done to level the carburetor so the floats would be correct.

Everyone on this site talks about the 10 degree tilt on the GM setup. We call it 10 degrees for simplicity. It is realy less than that. It measures about 7 1/2 I believe.
 

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Discussion Starter · #7 ·
Thanks guys! I think I've got it sorted out. I'm utilizing the original P30 engine and frame brackets. The driver side engine bracket is welded to a 5/16 plate that picks up three of the four mid-mount bolt holes. Part of the P30 frame bracket is welded to the original modified 302 frame bracket. On the passenger side the P30 engine bracket is again welded to a 5/16 plate that uses the front two mounting holes and two of the mid mount holes. I cut a hole thru the top plate in the crossmember and the P30 frame bracket is hung in between the front and rear pieces of the cross member. I'm square to the rails and reasonable parallel to the rear, I'm swapping in a Ford 9" so will fine tune it later. I'll get some pictures in the motor mount thread when I figure out how to do it. I'm using a high mounted HY35 turbo on a cut and flipped 6BT manifold. It makes for easy intake plumbing and opens up the area around the starter. I've got about 1" clearnce between the turbo and the hood, I can always use a 1" body lift if necessary to get some more if needed. Its good to see the engine sitting in the frame rails.
 
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