Engine limiter

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Coffee&Cars

Coffee&Cars

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12 miles from the track, Ohio
I have 440 duster . Building it as a drag car. The car has front engine mounting plates and a mid-plate mount. I am at a loss on how to build a engine limiter to stop the forward and aft movement of the engine. Any Ideas??????
 
Doesn't the rear tranny bracket help with that? Otherwise, they can put limiters on the K frame that tie into brackets that fasten to the pan rail.
 
never had much fore /aft movement always been left and right .Isn't the mid plate mounted ridged?
 
With then don't and mid plates installed, you have noticed movement fore and aft?
I would think that would not be an issue or even occur after the plates are bolted/welded in.
 
Go to summit and just buy an engine limiter kit, it's a lot cheaper than making one and it comes with instructions. If your making any kind of hp i would day you should use one. Any car I've seen with motor plates, uses an engine limiter.
 
Flat engine mount plates aren't real strong in the fore/aft direction, a limiter is a good idea. I usually make them to bolt to one of the original engine mount holes on the block and on the (sub-)frame. Could be a s simple as a piece of aluminum angle cut & drilled to fit, or it could be some 4130 tube with tabs welded onto the ends.
 
ntsqd said:
Flat engine mount plates aren't real strong in the fore/aft direction, a limiter is a good idea. I usually make them to bolt to one of the original engine mount holes on the block and on the (sub-)frame. Could be a s simple as a piece of aluminum angle cut & drilled to fit, or it could be some 4130 tube with tabs welded onto the ends.
Click to expand...

I used a round tube , single 3/8 heim joint on one end-welded on an angle to the other end, to fit one of the old motor mount holes , has adjustment if needed. "had the old rod laying around" :coffee2:
 
I'm a little concerned that a 3/8" SRE may be on the small side. A simple Rule of Thumb is that in a dynamic situation that a component "weighs" 3 times normal. So a 500 lbs engine will "weigh" 1500 lbs when the car launches hard or when the parachute hits hard.

Obviously some of that loading is taken by the mount plates, so the limiter isn't resisting all of it, but it is doing the bulk of the work. I should have mentioned all of this in my first post.
 
ntsqd said:
I'm a little concerned that a 3/8" SRE may be on the small side. A simple Rule of Thumb is that in a dynamic situation that a component "weighs" 3 times normal. So a 500 lbs engine will "weigh" 1500 lbs when the car launches hard or when the parachute hits hard.

Obviously some of that loading is taken by the mount plates, so the limiter isn't resisting all of it, but it is doing the bulk of the work. I should have mentioned all of this in my first post.
Click to expand...
as I said before, I knew a guy that had a low 9 sec 440 duster (496 I think), he used a 3/8" motor plate and stock trans mount. tranny brake also, no limiter, he never had trouble w/ it ! a 3/8" tube will be more than enough! only reason I`m doing it is because of a 1/4" motor plate-------jm2cents.
 
Not the tube size, the rod end. Really will come down to the quality of the rod end.

What does a drag race dressed 440 weigh? 700-750 lbs.? Really crude Rule of Thumb, in a sudden stop that engine will "weigh" 3 times that or roughly 2250 lbs (taking worst case guess). Std Engineering practice calls for a minimum factor of safety of 2, so now that engine "weighs" at least ~4500 lbs. Safe practice would be to size all of the parts in the limiter to not deflect at that ~4500 lbs loading. The plates will add something to restrain the engine, obviously, but unless you're willing to do that math my suggestion is to design the limiter to take all of the load. It's easier that way. :) And the difference in weight will be small enough that the only place that it would truly matter would be if we were trying to launch it into space.
 
Hey, Thanks for some good ideas. Problem solved. I looked up the kit. Its on the get it list. But like most of the products I get from Sumitt they say it works but usually doesn't on a Mopar, so you fix the part and then reinstall it a second time. That's why I named my first drag car TWO TIMES, LOL. For those who don't know.... Plate engine mounts do no prevent the engine and whole drive line from flexing forward and aft. Nor will adding a mid-mount (although it helps somewhat), but not a cure. Running a high power engine without the Mid-plate promotes more twist on the transmission case then it can absorb, causing it to crack or go KA-BOOM. Well anyways thanks for the info guys. PS. I named this one " Third Time Around"....
 
That's the kit i bought, it's just generic cut to length. I haven't installed mine yet but i have checked it out, should work just fine for ya.
 
I picked up 2 kits at Summit. One for each side. but as usual it is built for the
"other guys", It recommends welding the engine block mounting bar on horizontally to the strut bar. This dose not work on our stuff. The fix? On the pass. side. Bolt the engine mount tube straight on to the lowest engine mounting tab. Using a tube cutter, cut the strut tube on an angel so takes it to the inside of the frame rail pointing towards the front cross member I used 60 degrees. It lines up pretty parallel with the crankshaft centerline too. Driver side. Mount engine tube to the boss on the front of the block that's above the oil pump housing. Before mounting I drilled and re-tapped this boss for to a 7/16 fine thread using an ARP shouldered bolt. This side I lowered the heim joint mount bracket bringing it lower to the top of the frame rail and closer to being parallel with the crankshaft centerline. The drivers side is mounted forward like the other but on top of the frame rail with the bracket aimed at the strut mounting point so as not to put any undue twist on the heim joint. I will post some photos of this when I can figure out how to do that!!!! LOL
 
now wait a minute... the elephant ears keep it firm in place... isnt that the idea of the plate in the 1st place? or is this tech that has elvolved or learned since back then...
 
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