I have a 62 Buick Skylark with an aftermarket front suspension, sub frame, and crossmember. I'm putting a Buick 350 in the car. The car has rack and pinion steering and I have to make motor mounts to avoid steering shafts. I'm using the cardboard as a templet to cut the steel. I plan to use 1/4 or 5/16 plate welded to the crossmember and upright. I will drill a 3" hole in the plate for the steering shaft and a 1" hole with round tubing for the motor mount bolt. I imagine a small gusset for the tubing holding the bolt. In addition, I imagine using a gusset to hold the plate to the crossmember. The passage side will have a similar tube, but a more traditional perch mount. In addition, I may add a horizontal piece running parallel to the crossmember. It would attach high on the perch. Think this works? Advice please.
If I were going to the trouble to fabricate/weld motor mounts to a virgin chassis, I'd absolutely use a clamshell mount instead of those crappy old-style bonded rubber mounts. The bonded-rubber style can tear apart under stress. Guys resort to chaining or strapping one side of the engine to reduce torque stress on the bonded-rubber. Fabricate the steel clamshell bracket to bolt to the engine on each side, which also fits the selected clamshell/isolator. Use a Chevy clamshell with rubber or Polyurethane insert on the chassis side. There's multiple versions/styles of Chevy clamshell; if you're doing this, start with one that has usable Polyurethane inserts available. Even if you don't actually use the Poly insert, you've thought ahead for a later time when it might be desirable. Be aware that aftermarket "stock replacement" clamshell mounts with rubber inserts are dirt-cheap (~$20, maybe less) but may use half-thickness (THIN stamped) steel shells. Better to hit the Treasure Yard for OEM clamshells. A clamshell mount is ten times safer than the old bonded-rubber mounts. The steel frame absolutely prevents the mount from separating. The rubber (or Poly) insert isn't structural, just an isolator caged inside the steel structure. Fabricated steel engine-side bracket for LS-series engine, as an example. SBC OEM bracket and clamshell mount. Red Poly insert is encased in steel shell for safety: As said--there's several styles of these mounts, Pontiac used 'em too (but there's no aftermarket Poly inserts for the Pontiac style) so some research is in order. MAYBE you could pick up a middle-'70s Camaro bracket and clamshell mount set. (Assures future parts availability as Camaro stuff is "holy".) Redrill the brackets to fit Buick engine mount bolt pattern--or build a pair of adapter brackets with the Buick engine mount bolt pattern, and weld to the Chevy bracket. Then mount the clamshell/isolators on your chassis at appropriate height/position to get the engine at the right angle.
Nice simple, I would usea thicker 3/8 or even 1/2. You could real put some heat on the weld into it. I would add support on both side something like this
Out of all my buicks ne er have I broke an engine mount,...500 600 700hp,....stock mounts,....mounts fail when they get oil soaked,....most the aftermarket poly mounts have interlocking tabs that prevent separation as well,...that said it's a performance car so the solid mounts are the way to go. If you want some absorption you can get universal bushings and push them in a tube and obviously the tube would be you weld point the you would have some isolation
Car is going to be a weekend hell raiser and see some strip time. Is isolation required? Options as I see it: 1. Stick with my design Pro, has rubber bushing Con, the rubber is the week point 2. I could make the mount as pictured in Schurkey first picture easy enough. And still use the original plate idea(modifying it to fit). Pro Easy Con no isolation 3. The clam shell interlocking looks great but I'm not sure how to do it.
Of your worried about the mounts failing.....which at your power level i wouldn't be.....you can always make a limit strap or mount
Yes Ben I'm worried about failure. I got the aluminum heads, maybe nitrous, hope for 500Hp. I want a very low 11sec pass in a 3,000lb car. 12 lives that is exactly what I want. 12 lives motor plates look damn cook
I ran stk motor mounts with no limiters in my 3800 lb car at 10.90s and never had a failure. I still run stk mounts now, I just have plates that bolt to the head to frame now
OK I will go with the original plan. I tend to over think stuff "paralysis cuz of analysis" Thanks Ben and every one replying you guys are great
I think HR parts mount will fit the 350 also,..it's absolutely bullet proof,..driver side is all you need
See if they can make a modified kit for a 350. Its just the plate that mounts to the block. Or sell you the parts un-assembled and you can use from it what you need. They make them so they may work with you: https://welderseries.com/store/MOTOR-MOUNT-KIT-BUICK-V8-4-HOLE-p51163385 "PROBLEM SOLVING HOT ROD CHASSIS PARTS FOR 40 YEARS"
Here is the plan as of 3:08 3/12/2022. lol Go with my original idea for mock up. Tack stuff in place, get the steering set up and other things in place. If I think I can make the other ideas work go for it. If not burn in the existing plate.
Thanks again I contacted HR They sell 350 mounts. On the pricey side but I will probably purchase them.
