Can I use solid motor mounts?

[Nashty]

I'm getting ready to mount the engine in the chassis and am trying to decide why I would need stock style (or the HRparts) mounts. Is there any reason NOT to just mount the motor solid?

Car is mostly drag raced but will see some street time.

I'll use a poly trans mount.

 

[Brian Mc]

Get the HR mounts. It's a tough 200 bucks to spend, but worth it. He's a vendor that needs our support because of the excellent products.

 

[turbosam6]

I actually read somewhere that a lot of guys are getting away from solid mounts because the motor will actually distort when making high HP, because the solid mounts to the frame won't allow it to "flex". I guess this causes the bores to distort. I dunno, I read it somewhere, maybe somebody more experienced can chime in. But in any case, I would definitely use the HR mounts, I got them and they rock. Whens that car gonna be done? I gots to see that!

 

[Nashty]

I guess I would say if the block is flexing and the bore is distorting then I've got bigger problems. I guess if the chassis was flexible (as in a flaccid Regal platform) the chassis may be loading the block. I would think my car would be doing that now don't you think? I'm using both mounts and can say first hand that those mounts aren't flexing very much. The car vibrates way too much IMO.

The car will be pretty stiff up front when done with the strut reinforcements. That may keep flex in check and help out. I do think that a motor plate would work better though.

So you think the HR mounts would allow it to "swim around" a little up front and that flexibility is necessary?

I look at it 3 ways.

1- An extra $200 I don't have
2- Not as slick as what I had in mind
3- Maybe a little more civil than solid mounts. (Trust me, this car won't be a big road-tripper when done. Struts offer a whopping 1" of compression in front end travel, 2 5/8" total.)

 

[REDS HOT AIR]

hope it dont shake all your teef out dentures aint cheap ..

 

[sloride]

Id think you probably be dealing with alot of false knock under street driving w/ solid mounts.

 

[Nick Micale]

I look at it a little differently after running a solid mount on a 3.8 for a short time. I made a tie down to the frame bolted to where the A/C compressor was. The solid mount made me very uneasy about cracking the block as it is very thin at the mount area. Heard of this happening before.

Also had a bracket at the trans bellhousing area to the frame. So my opinion is to use H&R mounts, or stock ones with a firm engine tie down. Never had a false knock problem when using the solid mount

 

[machinegun]

I will let you know about my opinions and research. First solid mounts are going to be crazy vibration. These engines are strange anyway. They do have a distinct vibration to them. Second is the engines produce so much torque that a solid mount will shock the block hard. This could cause overdue stress on the block and possible other damage. The Mounts will help to absorb some of this shock so it is not transferred to the frame or block. Should help you out some. It also sounds like this is not a stock engine and so the torque and vibration issues are quadrupled. Mostly everyone running a stock block car into the low 10's and nines are going this route. I personally do not recommend a tie down strap. Some have used with success, but they usually caus problems with broken bolts. alternators, alternator mounts and stress on heads that some have theorized leads to blown head gaskets. This is of course just my opinion and some of the things I have talked to others that have cured their issues with the poly mounts. Hope this helps.

 

[talstar]

I have both h&r mounts on my car and haven't had any problems with them. There is some vibration, but it's not that bad.

 

[top gun]

The HR parts poly mounts are great, I run them on my 800 hp stock block car and my 1400 hp stage motor car without a problem.

 

[REDS HOT AIR]

Originally posted by top gun
800 hp stock block

thats nasty there

 

[Nashty]

I think I'll go for the HR type of mount but modify it to fit my application. Maybe I'll shop around and find a SBC mount I can weld and redrill that was meant for a street rod. Not sure yet.

 

[WIKEDV6]

Hey Roger what is up? We have two RX7(GN powertrain) with solid mounts without any problems, one is a low 11sec high 10sec car and other one is a 12sec car. Only problem they said was too much vibration (these are street cars)
goodluck
Prasad