it's about time to work on my motor mounts on the s10 volvo swap... the stock motor mounts are out... it's an '89 and they are HUGE soft things.
I saw a guy using GM poly trans mounts which looked like a good option... but I was wondering about a solid metal mount to the frame?... other than the obvious vibrations is there any issue with this (cracking frame or something like that?
thanks guys mark
If you use a solid front mount you use a solid rear mount. (which in your case will be fine) If you use a poly or rubber front mount use a similar mount in the rear.
so no major issues with solid mounts?... seems vibration would be less of a factor being framed instead of unibody yes?
It probably won't vibrate any worse than the stock 4.3 did, but solid motor mounts are a rude thing. They also have no room for error, and unless everything in the frame is properly stiff, you may end up breaking mounting tabs and such.
I'd be real tempted to use the mounts from the donor engine, and fab whats needed for the frame mounts.
My daily driver has had solid engine mounts in it for the last 5 years or so. Normal V-8 rear wheel drive metric framed Chevy. The engine mounts are solid with a polyurethane tranny mount. There's all different styles of solid mounts and some are better than others. I have one 1/2" bolt attaching the mount to the frame on each side with the normal 3 bolts attached to the block. I've had the engine shift just once, and only a little bit. It's also a pretty low horsepower engine, but I will run it hard. As much as I hate to go directly against what's been posted, my research told me to have one "soft" spot in the drive line to allow for chassis flex. It probably won't be a big deal at all until the horsepower gets up there, but without a flex point somewhere, that's when things crack, usually something like a bellhousing. I spend quite a bit of time circle track racing street stocks, so if there's a problem, it will show up there, but the frame is also stiffened up with a full roll cage to keep chassis flex to a minimum. My engine mount bolts are grade 8, safety wired in, and I don't nearly have as much trouble out of them as I expected. Depending on how you design the solid mounts and attaching points, you can bolt it in and forget about it. Just don't forget the safety wire. Vibration does become an issue.
unfortunately the stock mounts are 3 peice on volvo... the motor mounts themselves are to wide (I might be able to get one of them to work) the soft mount portion is HUGE... and the earlier type isn't known for it's strength or lasting long.
heres one a guy on turbobricks made that i think may work out... with steel instead of alu using GM poly trans mounts
It always helps if you own a welder and a pile of steel (or aluminum). You can build whatever you need that way.
got a mig/flux harbor freight 220v... my welds are ugly but plenty strong.
I missed the "Volvo" part of the story. Are you using red block turbo, or white block? If red, just head for the junkyard and get the mounts from a 240. They are compact, and designed to bolt down to the flat surface of the crossmember. Only downside is they are designed to break off in an accident to slide the engine under the floor instead of into the firewall.
If white block, the only factory option is 960, and they are pretty big.
red block... s10 makes it pretty tight even with 240 mounts
Maybe use the top 2 pieces, fab the crossmember mounts...
I agree with the suggestion to provide at least one flexible mount. The engine and transmission combination were not designed to be part of the frame and will likely crack at the weakest spot. I think the engine vibration connected directly to the frame will break something somewhere else that happens to be in resonance at some RPM or another. I strongly advise flexible mounts somewhere in the system.
Back in the earliest days of board track and speedway racing the Myers Engines were solidly mounted at the flywheel end and the front was a pin in a socket to allow for the flexible flyer chassis designs. According to the record these things were scary fast.
Edit on my post. Those were MILLER Engines.
so I think i've got the frame mount/pad figured out...
how thick of steel should I use for the engine side of the mounts? will require a plate and then a short "arm" to meet the frame mounting pad.
something like 1/4" for the engine side and then 3/16 for the support beam portion?
Look at what the factory uses for mounts. The stamped steel units are maybe 1/8"...
How about a piece of 3" Channel iron? Worked for me.
Dan
