Norwood

[Track Junky]

Toss the headers and get some that fit right. Who makes those?

[Sieg]

Originally Posted by GregWeld

Just burn it.

Tried it..........epic fail............again.

[Sieg]

Originally Posted by Track Junky

Toss the headers and get some that fit right. Who makes those?

Doug's D368's..........they fit right.

[Flash68]

Originally Posted by Sieg

In an effort to neutralize the little vibe that's left I'm going to replace the right side Moroso solid motor mount with an Energy Suspension urethane mount and see if that has any neutralizing effect. I'm leaving the left side mount as the header to steering box clearance is about 3/16".

Thoughts?

Solid mounts in your reverse burnout street car? Interesting.....

[Vince@Meanstreets]

Originally Posted by Sieg

The most annoying vibration feedback I'm getting now is in my right foot which tells me motor mounts.

The concern is the steering box clearance.

Are the urethane mounts rigid enough to keep the header from contacting the steering box?



..........oops! Just realized I forgot the F'n idler arm!

any witness marks?

Take another look, is there any part of the engine/trans touching the body? Trans bellhousing bolts? The ones on the drivers side.

Solid mounts transmit alot of NVH.

[Sieg]

Originally Posted by Flash68

Solid mounts in your reverse burnout street car? Interesting.....

[Sieg]

Originally Posted by Vince@MSperfab

any witness marks?

Take another look, is there any part of the engine/trans touching the body? Trans bellhousing bolts? The ones on the drivers side.

Solid mounts transmit a lot of NVH.

Just to clarify regarding witness marks......the motor is still solid mounted.

The vibe in the throttle is most noticeable when cruising at highway speeds of 60-75 mph while using light on/off throttle inputs to maintain speed or following distance.

To the best of my knowledge there are no contact points as I clearanced/smoothed the firewall when I installed the transmission and I've had it out once after the initial install and there's good clearance around the bellhousing bolts.

No witness marks on the steering box or idler arm.

I've 'heard' the urethane mounts are pretty rigid but those clearances are pretty tight, thus why I'm leaning to replacing the right side only and see if anything changes.

[Vince@Meanstreets]

even if you change one it won't make much difference since the other side is solid mounted. It would if you had a hinge or spring mount that will flex.

One of the ways to find the frequency of the vibration and with some mathematical calculations you can determine if its engine, pulley or rotational issue. A simple tool for measuring the vibration frequency is the sirometer you can get one from Briggs & Stratton shops.

We use to use them to determine and narrow down causes of vibrations in Dodge diesel trucks.

[SSLance]

I have newish poly mounts on both sides in my car and I have witness marks where my header contacts my steering shaft...which has over a half inch clearance when sitting static.

Being all too familiar with solid mounts to cure clearance issues on other cars, I'm tempted to say you might need to learn to live with the vibration if they are the cause. You've gots some tight spaces there...

[GregWeld]

Funny how we try to turn a 45 year old Chevrolet into a Rolls Royce....