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Show off ur motor mounts.

427K views 423 replies 181 participants last post by  boomersrule55 
#1 ·
Well, I'm sure this will be a very popular subject here so why not start a thread to give some ideas for fabbing or adapting motor mounts? I myself am interested in pics of adapting Fluid mounts to a 79 Dodge Ramcharger Crossmember... Though any pics/info about mating the mounts to any 80's Dodge/Ford/Chevy crossmembers would be greatly appreciated too! Thanks.

Michael
 
#100 ·
I assume the 3.5" is the same clearance as between the springs and their max travel bump stops for compression? Also may I humbly suggest that you consider some flat 3/16" to 1/4" plate gussets at your weld zones, in front and behind? Just enough to reinforce during the infamous 'Cummins shake' at shutdown. With almost a dozen beads there is a chance for stress risers or hydrogen embrittlement and future fractures.
 
#101 · (Edited)
when we cut out the angles we reused to scraps to do that on the inside thats why theres two beads on each angle. and for the springs its about right the springs dont have much flex in them


 
#102 ·
Is the 3.5" clearance measured "now" at an unloaded ride height...you may want to factor the significant weight and loaded spring "sag" that will occur once the 4BT is mounted inside the rails. A somewhat economical option /solution may be a spring over axle (SOA) lift but it is still $ and there is a host of steering geometry and axle-wrap considertions...gotta love projects - overtime/overbudget!
 
#103 ·
ya we are bolting in the cross member with grade 8 bolts so there is some room for adjustments once we get the motor installed. also we have a 4" suspension lift so it already has upgraded springs and they are STIFF.
 
#107 ·
My mounts. used the P30 engine brackets, frame brackets and the original 5.0 driver side mount. The front corners of the block are a little close to the cross member, I will either notch the cross member or fab spacers to lift the mounts up but I'll wait until I get the 9" rear installed.
 
#108 ·
More
 
#109 ·
Very tidy!!!:beer:

A bit tight like you said. That crossmember is awesome, I wouldn't
try to notch if all I had to do is successfully shim up the motor 1/2"
at the mounts. The crossmember is in a very good place structurally,
and tying into your frame that close to it is great. You will have less
frame roll and the load will distribute really well.

So the question is "Will you get interference at the tranny hump or
the hood or elsewhere if you go up a bit?"

(That is one of the more straightforward 4bt repowers I've seen on here)
 
#113 ·
Very tidy!!!:beer:

So the question is "Will you get interference at the tranny hump or
the hood or elsewhere if you go up a bit?"

(That is one of the more straightforward 4bt repowers I've seen on here)
Thanks. I've got about 1.5" between the top of the turbo and the hood so I've got plenty of room to go up, that's most likely what I'll do. The tunnel isn't a problem. I also used the original tranny cross member in the stock location so I can use the original rear drive shaft, not sure about the front yet with a 3-4'' lift for 36's.
 
#112 ·
That's very ingenious use of existing hardpoints DarylB:idea:

Is there gussetting under the (Blue) mount plate? Pretty important
to strengthen the fore/aft direction in case of repeated hard braking
or a (let's hope never) front end collision. (I realize those plates are
super thick, well over spec, but the hard corners are places of stress
concentration.
 
#114 · (Edited)
They're welded all the way around w/ 7018 low hydrogen. If anything is prone to break it'll be the weak CJ frame before the mouting point breaks. If you notice on the driver's side I had a crack where the factory seam had broken and a few cracks. We welded it all the way up, and down into one of the bolt holes where it had cracked. I'm going to clean up the mounts later & Grind them down. Also my logic was to span the weight of the engine, between the two points, as to not already stress a weak frame. Thinking about doing a CAD design on them and see if They'd sell :idea:
 
#117 ·
Thanks! I ended up cutting up the $100+ AC mount I got from cummins because I liked those mounts so much :) Ended up being easier to cut up the AC mount and brace it rather than redoing the passenger side mount.

Now if I could figure out how to get paid more maybe I could finish this damn thing this year :)
 
#126 ·
I moved the original Bronco mounts forward to allow the use of the original 4BT mounts on the engine. I mocked up a few different configurations and this seemed the best for my setup. The cross member did not need to be modified, but I did move a frame corner brace on the passenger side about 4 inches. I also notched the passenger side frame about three quarter inch for starter clearance. The starter just touched the frame. I will notch the oil pan to provide more clearance for the differential. There is about 5 inches of clearance now. It is a rear sump oil plan. The Bronco has a 3.5 inch suspension lift and a one inch body lift.

James
 

Attachments

#130 · (Edited)
The first picture just shows the basic parts of the frame side of the mounts tacked-in. The flat plate extends through the frame rail and was welded to the outside wall of the frame rail, prior to inserting the rounded piece into the cut out area, plus I added some bracing underneath. I'll look for more pic.s.

The mounts are fluid filled out of a P30 van w/ 4BTAA, the brackets are home made.
Jon
 
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