S52 swap with UUC flywheel - shakes like hell!

[treff-7]

Hey guys,

so i sort of finished my obd1 s52 swap and from about 2000 rpm the whole chassy shakes really bad. it also does it in neutral standing still so it's not the drive train for sure. also does it with the clutch disengaged so it's before that. I'm suspecting the flywheel but not 100% sure. I've never driven or ridden in a s52 powered car so i don't know what it should sound like but from all the youtube videos mine sounds different. it has good power i don't think there's a problem there but sounds like a v8 inside the car. maybe i'm only hearing the vibrating chassy.
any ideas?
thanks!

[golde30]

Did u use the spacer ring and bolts from UUC that came with the flywheel?

[RobertK]

Do you happen to have a crankshaft under drive pulley?

[treff-7]

no under drive pulleys.
yes i used the bolts and the thin plate that came with it however i put it under the bolt i think. was it a spacer? i bought it used and no instruction came with it. it spun freely and didn't rub. Chris Castro checked it and also said that it didn't rub.

[golde30]

You used it rite as far as I can tell... Maybe something simple like mounts are not tight...

[SHunter]

Check to make sure your exhaust isn't touching the body anywhere. I thought I had plenty of room when I got the engine in but you could just feel the engine booming inside the cabin. It was cool for a minute but would get old real fast and felt like the engine vibrating the whole car. One of my headers was just touching the subframe barely. I stuck a shim under the mount on that side and now its smooth and quiet.

-Steven

[MaksV]

Depending on how much shaking is going on - it is not uncommon to get whats called "flywheel chatter" from a lightened flywheel, due to the unballincing you are doing to the motor.

[treff-7]

You used it rite as far as I can tell... Maybe something simple like mounts are not tight...

they should be tight but i will double check. BTW i always wondered why people use the e21 (?) tranny mounts. i read that they are stronger but i don't believe that. the stud is bigger on it, that true but it is really soft. a lot softer than the e30 one. i'm thinkng about swapping it out.

[treff-7]

Check to make sure your exhaust isn't touching the body anywhere. I thought I had plenty of room when I got the engine in but you could just feel the engine booming inside the cabin. It was cool for a minute but would get old real fast and felt like the engine vibrating the whole car. One of my headers was just touching the subframe barely. I stuck a shim under the mount on that side and now its smooth and quiet.

-Steven

Chris told me that it is normal for these engines to shake especially when they have LW flywheels on them but i don't think he meant this much shake! i will check on the tranny because i remember when i put the engine in, there was almost no room above the tranny. maybe i was wrong there's actually no room at all! i was trying to feel around in the cabin if i can feel where the engine might hits it but no luck. now i'm thinking that if it doesn't hit it but touches it all the time, it can just shake the whole chassy.
i also listened to the exhaust when i drove under a bridge and that sounds fine. no v8 sound there.

[treff-7]

Depending on how much shaking is going on - it is not uncommon to get whats called "flywheel chatter" from a lightened flywheel, due to the unballincing you are doing to the motor.

as far as i know flywheel chatter is something totally different. a lot of times people swap their dual mass flywheel to a single mass lightweight flywheel and keep using the dual mass clutch. by doing that they eliminate the part that filters out the small vibration coming from the engine (and amplify it with the lightweight flywheel). that vibration shakes the internals of the transmission and that makes a chattering noise. i have something that makes my car sound inside like a subaru wrx.

[RobertK]

they should be tight but i will double check. BTW i always wondered why people use the e21 (?) tranny mounts. i read that they are stronger but i don't believe that. the stud is bigger on it, that true but it is really soft. a lot softer than the e30 one. i'm thinkng about swapping it out.

Side by side the E30 mounts are definitely softer than E21 mounts.

[treff-7]

Side by side the E30 mounts are definitely softer than E21 mounts.

which e30 mounts? manual or auto? cuz the e30 auto is really soft and kinda skinny but the manual one however is hard and not even round. it's octagon shaped IIRC.
as far as i know of course...

[golde30]

My s50 sounded like a wrx when cyl 1&2 lost all compression. Maybe you are misfiring, bad coilpack?

[10Toes]

My s50 sounded like a wrx when cyl 1&2 lost all compression. Maybe you are misfiring, bad coilpack?

I would agree with a misfire, these engines normally run pretty smooth.

[RobertK]

which e30 mounts? manual or auto? cuz the e30 auto is really soft and kinda skinny but the manual one however is hard and not even round. it's octagon shaped IIRC.
as far as i know of course...

Manual mounts. I have a new set of each and the E30 ones are softer.