• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

B230+T5 3k rpm shake

I have the STS Machining lightened flywheel, Yoshifab stage 2 clutch, and pressure plate. I should have mentioned but there is a slight vibe when driving as well. You can slightly feel it pulsing if that makes sense.

But on another note, this may be just the way it is normally with this clutch setup and engine?

I really think this is just the second order vibes of the engine being channeled through a light flywheel and amplified by a generally noisy gear box.

Since the warmer weather has kicked in here I have been driving my car a lot lately. The vibes are by no means 100% gone but with the larger slip yoke, setting my driveline angles, as well as swapping out the poly trans mount for a rubber one, I am pretty happy with the way the car drives now. I guess that's what it all boils down to in the end. If your not happy with it keep digging.
 
I think you are correct, that the vibes are going to be there when you mate together a t5 and a redblock. My vibe is definitely liveable, but when I get in my stock 240 with an m46 it feels like a much smoother and refined car than my 740 t5. Last question, what are symptoms of improper bellhousing alignment? This is the last thing I've not checked.
 
I think you are correct, that the vibes are going to be there when you mate together a t5 and a redblock. My vibe is definitely liveable, but when I get in my stock 240 with an m46 it feels like a much smoother and refined car than my 740 t5. Last question, what are symptoms of improper bellhousing alignment? This is the last thing I've not checked.

misaligned bellhousing?
premature input shaft bearing failure, possible premature clutch failure, possible vibration.

The engine has 2 dowels on it to center the bellhousing, they both need to be there
 
Yes, this is what I mean. Idk, maybe I am just chasing my tail but there is still a pulsing/vibe at around 2-2.5k I want to remove and I believe it's possible. I don't think I would feel a pulsing through the wheels when driving if my angles were 100% on point. These are my angles right now, the car lowered on two cut coils front and rear. Note that my driveway is not a flat surface. The first angle is trans, then the first shaft, the second shaft, and diff. I've messed around with the pinion angle and the height of the CSB a lot but if someone has advice I'd love to hear it.
Screenshot-2021-06-04-081316.png

misaligned bellhousing?
premature input shaft bearing failure, possible premature clutch failure, possible vibration.

The engine has 2 dowels on it to center the bellhousing, they both need to be there
 
Thanks, I'll definitely check it out. I currently have my pinion at 5.5 degrees, right in between the trans angle 6.0 and the first shaft 5.0. It's the best I've ever got it, but I'm sure It can still fine-tune it more.
 
I'm assuming the only adjustment would be through an adjustable panhard bar? I'm almost sure my driveshaft angles in the vertical plane are properly set to have no vibration. Pretty sure there is a compound angle and the horizontal angles are not proper.
 
Your pinion gear is offset and the axle tubes are the same length. Not a whole lot you can do about that.
 
NVH

I would do some more Google research on automotive NVH diagnosis.

It looks like there are some apps available for NVH diag.

Or maybe try a mechanical instrument like a vibrating reed frequency meter to get some measurements.



... it is happening at idle?, so it's not my driveshaft angles. The sound is a pretty deep reverberation that fills the cabin around 2-2.5k RPMs.
 
Last edited:
Was intrigued to find this thread after struggling with the rattle trap T5 in my 740 for almost 4 years now. My setup is a balanced squirter B230FT with ebay rods, IPD turbo cam , Yoshifab 16 lb whywheel, v6 T5 with fox body input shaft and Camaro tail shaft. Modified two piece driveshaft with standard slip yoke.

The swap was done when the car was basically stock, with the stock dog dish flywheel there was very minimal rattle. Once installing the new motor with the light flywheel the problem got much worse.

One thing to note: 240s and 740s have some sort of driveline dampening on manual transmission cars( ie giubo or rubber coupled rear shaft) With a T5 swap the lack of any damping allows for engine harmonics to resonate in the driveline. Others have posted some success with heavy ford damper yokes which supports this theory.
I've always wanted to try a Cadillac CTSV giubo joint on the back of the transmission. My thought is drastically reducing the ability to transfer vibration to the driveshaft will eliminate the rattle. The issue is where to find a T5 yoke that will work, custom made is probably the only option. If anyone knows where I can get a custom yoke made please share.
 
I wound up using that heavy slip yoke with a 1330 to 1310 conversion u-joint and a bunch of spacers to get everything lined up properly. Shortening the torque rods to their absolute limit got me just within spec for operating angles. The car is now, to use tfrasca's words, downright tolerable. It was not cheap: F6ZZ-4841-BA.

<img src="https://liam821.com/h/242/Jan-Jun%202021/IMG_0705.jpeg" width="1200"</img>

<img src="https://liam821.com/h/242/Jan-Jun%202021/IMG_0706.jpeg" width="1200"</img>

<img src="https://liam821.com/h/242/Jan-Jun%202021/IMG_0716.jpeg" width="1200"</img>

<img src="https://liam821.com/h/242/Jan-Jun%202021/IMG_0717.jpeg" width="1200"</img>

<img src="https://liam821.com/h/242/Jan-Jun%202021/IMG_0719.jpeg" width="1200"</img>

<img src="https://liam821.com/h/242/Jan-Jun%202021/IMG_0720.jpeg" width="1200"</img>
 
Back
Top