70 LT1 Bellhousing

[Joe S.]

A friend grenaded his Clutch tonight and it took out the bellhousing. Flywheel may be torn up also. Towed it to my shop today and will pull it apart tomorrow.

Checked through the entire 70-72 judging guide but nowhere in there could I find the part # for the bellhousing. Maybe I missed it, but went page by page.

Could someone tell me the part number and if they are readily available out there or do I have to hunt for a used one?

Thanks...

[Joe L.]

Re: 70 LT1 Bellhousing

Joe-----

Assuming that the car is not a ZR-1, then the bellhousing required is a GM #3899621.

It's also possible that very early 1970 with LT-1 used a different flywheel, clutch and bellhousing. I've never been able to confirm this and I doubt that it's true. But, it's a possibility.

To EASILY confirm what bellhousing you require, look at the starter NOSE. If the nose is cast iron (as it VERY likely will be), then you require the 3899621 bellhousing. If the nose is aluminum (VERY UNLIKELY), then you require the GM #3858403 bellhousing.

Both of the above bellhousings are long-since GM-discontinued. They are not difficult to find used, however. The 3899621 can be a bit "pricey" in the used marketplace, though. Expect to pay in the range of $100 to $200 for one. The '403' can be had for $25, but I doubt very much that's what this car will require.

TIP: if you have the time, look for a bellhousing with the casting number 464697. If the clutch fork ball stud tapping is on the UPPER surface of the "oval" shaped boss on the INSIDE of the bellhousing, this will be a GM PART NUMBER #3899621 bellhousing. However, only you will know that and likely not the seller. He will think that it's a 464697 bellhousing that hardly anyone wants, so he'll sell it cheap.

[Joe S.]

Re: 70 LT1 Bellhousing - Thanks Joe! *NM*

[Brian Monticello]

Re: 70 LT1 Bellhousing

Joe,
That picture gives me the willies. Good thing it exploded with shrapnel directed towards the street and not up into the car. What was your friend doing when this happened?

Brian

[Joe S.]

Re: 70 LT1 Bellhousing

Brian,

As he may well read this I'll tell his side of the story. ;-)

He says he did a sprited shift between 2nd to 3rd and that he definately hit 3rd gear before it exploded.

Of course I believe him. Even though I've never seen a clutch do that except when MISSING the shift. Oops, just kidding of course ;-)

[Frank C.]

Re: 70 LT1 Bellhousing

This why I use scattershields in the M/T cars I drive. If you only show them and have them judged fine. But if you drive 'em, leave the stock B/hsg on a shelf in your shop, because you know you can't drive some of the monsters we own without sticking your foot in it. And you won't usually have a foot after this happens!!!

[mike cobine]

Re: 70 LT1 Bellhousing

A friend did that one night in a '36 Chevy coupe. He did have a scattershield, but didn't have the block plate on. The flywheel exploded and tore the flange off the block, letting the transmission and engine drop in the center until the headers hit the ground.

It happened about halfway down the quarter at St. Louis International at night and did it ever make for a show of lights.