LS3 Clearance Issues to Frame

[Toddoky]

I hope all goes well for you Perry, but the inclusion of your steering rack set-up into the mix might end up being the variable the kills the deal. Does your rack mount in front of the engine crossmember, or behind it? Also, what transmission are you going to be using?

[Zombie666]

The steering rack is mounted in front of the cross member and my tranny is GM's 4L75E. Right now I have 3/8" between the front of the oil pan and about 3/4" between the oil pan and the cross member. I'll post a picture

Perry

[Zombie666]

The picture is not the greatest, but you get the idea. We will be test fitting the body this weekend.

Perry

[Zombie666]

Although the rack is mounted in front of the cross member, the tie Rod ends and steering arms are in the stock location

Perry

[Z06vet]

The angle on that rack steering shaft looks severe... how do you handle that?

[Toddoky]

It will be interesting to see if the parts end up being compatible with each other. I think I read previously in the thread you were going to be trying the Hooker rear-bias A-body engine brackets, if that is the case I can tell you up front that fitting your 4L75e trans into your car at an inclined position that produces desirable U-joint working angles is going to require transmission tunnel modifications...the stock profile of the firewall/tunnel transition area will not accommodate the size of the multi-piece bellhousing 4L60-4L75 transmissions without it. All of the late model GM automatics and the Tremec T56 manual transmissions install easier by using the Hooker forward-bias A-body engine brackets (i.e. no cutting required to install the 4L60-4L75 transmission) but that engine position may not be compatible with your steering rack set-up.

[Zombie666]

I just wanted to follow up what seemed to be a predicted potential clearance problem. In the end I did use the stock frame mount but added a 1/4" spacer between mount and frame. Once I got the tranny mount in place, I'm left with a 1/2" gap between the front of the oil pan and the top of the steering rack. I consider this a success. I do agree that going with a single supplier will make everything easier but I saved myself a ton of money.

[Zombie666]

Another follow up from Toddoky's valid comments about having to cut the tranny tunnel. With the spacers mounted under my frame mounts, I did leave the frame mount in the stock location that being bias to the front of the cross frame. Today I test fit th body and I'm extremely relieved to say that I have at least 1/4" clear although the picture doesn't reflect that I couldn't get the camera in far enough to show it. Having said that I will massage the tranny tunnel to get a little more room.

Perry