Transmission crossmember

[tfeverfred]

Hey, guys. Could I please have the location of the front of the transmission cross member from the base of the kick up for your stretch body? I'll be using a 350th transmission. Thanks again!

 

[EX JUNK]

Fred, as close as I can measure it's 31" from the front of the transmission cross member to the front of the rear kick. My transmission mount is on the rear of the cross member. Check the picture below and see if that helps.



Jim

 

[tfeverfred]

CCR's trans mount gets bolted to the cross member. Where the transmission mounts is at a slightly forward angle. I always like seeing your chassis, but due to CCR's design, it won't help me this time. Thanks.

 

[tfeverfred]

Okay, after another look at CCR's manual, it suggest mounting the trans bracket to the engine & transmission assembly, loosely setting them it place, tack weld the cross member, remove assembly and finish weld. I was trying to save a little time, but it seems, in this case, doing it their suggested way, is the best way.

 

[RESINATOR]

I will get you that dimension tomorrow so you won't have to go thru that work. Do you need the motor mount dimensions also from the same point? Long Body, SBC and TH350 Correct?

 

[tfeverfred]

I will get you that dimension tomorrow so you won't have to go thru that work. Do you need the motor mount dimensions also from the same point? Long Body, SBC and TH350 Correct?

I have the motor mount location from your plans, 21 3/8" from the front cross member. And yes, 350 SBC, th350 and I'll be using your long body.

Thanks for looking in.

 

[fletcherson]

You should be able to set it up without having it all in place if you allow for some variance in your mount, ie, slotted hole, etc...

 

[RESINATOR]

I will get the motor mount location for you also,.. from the kick-up as a double check since it not our frame

 

[tfeverfred]

You should be able to set it up without having it all in place if you allow for some variance in your mount, ie, slotted hole, etc...

Yea, that's what I've done. A while back, I did some calculating and marked it off. As in most blueprints I allowed a tolerance. In this case + or -, 3/16".When I measured Paul's trans mount, I came up with 24 1/4", but Paul's frame is a frame BASED on CCR's blueprints. It has some modifications.

So, I decided to take my measurements from the motor mount. I found a blueprint for a SBC and the measurement from the center of the motor mount to the end of the block, where the trans hooks up is 16". I went to TCI's website and found the measurement of a th350 from front to the trans mounting holes, 20 3/8". That gives me 36 3/8" total from the motor mount. BUT, as stated earlier, CCR has a separate bracket that attaches to the trans, then to the cross member. The figure that I need to finish the equation is the fitted length of the trans bracket, when attached to the cross member.

So I ball parked that length at 4 1/2". Giving me a grand total of 40 7/8" from motor mount center to the front of the cross member. Now, I'll see how far off I am, when Resinator gets back.

 

[tfeverfred]

Wow..... just remembered, I wanted my engine mounts closer to the cross member at 18 3/4". That doesn't change the total measurements of the engine and transmission. So, the main measurement I need is from motor mount to crossmember. Then, I'll be able to decide on a final distance from cross member to engine mount.

The GM blueprints show a SBC at about 27 1/2" from water pump housing to the end of the block. If I move my mounts forward, I'll still have clearance for the fan and radiator. About 7 1/4".

Motor mount to the kick up will also work.

 

[tfeverfred]

I will get the motor mount location for you also,.. from the kick-up as a double check since it not our frame

Thanks, that will be really helpful.

 

[fletcherson]

Yea, that's what I've done. A while back, I did some calculating and marked it off. As in most blueprints I allowed a tolerance. In this case + or -, 3/16".When I measured Paul's trans mount, I came up with 24 1/4", but Paul's frame is a frame BASED on CCR's blueprints. It has some modifications.

So, I decided to take my measurements from the motor mount. I found a blueprint for a SBC and the measurement from the center of the motor mount to the end of the block, where the trans hooks up is 16". I went to TCI's website and found the measurement of a th350 from front to the trans mounting holes, 20 3/8". That gives me 36 3/8" total from the motor mount. BUT, as stated earlier, CCR has a separate bracket that attaches to the trans, then to the cross member. The figure that I need to finish the equation is the fitted length of the trans bracket, when attached to the cross member.

So I ball parked that length at 4 1/2". Giving me a grand total of 40 7/8" from motor mount center to the front of the cross member. Now, I'll see how far off I am, when Resinator gets back.

In my old shop, we routinely performed engine and tranny swaps, etc, and you would be suprized how different they are. The same basic setup from the same model car and there is a big difference in the marks on the cross member mount surface after the swap. It used to bother me until I realized that is was just manufacturing variance.

 

[tfeverfred]

In my old shop, we routinely performed engine and tranny swaps, etc, and you would be suprized how different they are. The same basic setup from the same model car and there is a big difference in the marks on the cross member mount surface after the swap. It used to bother me until I realized that is was just manufacturing variance.

Exactly. An inch here or there changes everything, but in all those measurements, there has to be at least one constant that doesn't change. I my case, I think it's going to be engine mount to transmission mount. And since my reference point is the rear kick, everything falls into place with that variance you mentioned as a "given" or allowable tolerance. I dodn't think it's going to be that much.

I'm betting it's 65 3/16 from kick up to motor mount center. Give or take 1/4".

 

[RESINATOR]

So here are the dimensions off the Extended body frame we have fully assembled in the back.
All these are from the top of the main rail where it meets the 45* kick-up

To the back side of the 1.5"x 3" transmission crossmember = 21 5/8"

To the pedal pivot centerline of the master cylinder bracket = 41 1/2"
(down 2" from top of frame to C/L pivot)

To the center of the motor mount bracket on the frame = 63 3/4"
(down 5/8" from top of frame in front, tip downhill toward rear 3-4 degrees)

These dimensions are out of our fixture so our long body fitment will be correct.
There is room to go forward 1/2" on the motor and trans dimension if you want more clearance at the distributor and steering box but do not move the brake pedal bracket

 

[HenrysT]

Maybe you should just get your suspension brackets tacked/welded so it can be a roller. Get your body, and do the rest. Maybe your measurements should come from the rear end center line, so if you center your P/U bed to the rear end, your body MIGHT not be at the kick up.(I don't even know if you're going to run a P/U bed)

 

[tfeverfred]

Maybe you should just get your suspension brackets tacked/welded so it can be a roller. Get your body, and do the rest. Maybe your measurements should come from the rear end center line, so if you center your P/U bed to the rear end, your body MIGHT not be at the kick up.(I don't even know if you're going to run a P/U bed)

Well, I won't be using a pick up bed and I already know where CCR's body meets the kick up, having owned one before. The suspension bracket and rear end pieces are forth coming, but really don't have anything to do with the measurements I'm asking for at this point. I have a post in my build thread, I think, where I give the reasons I need fairly close measurements at this time. Take a look and give me your thoughts.

Everything I'm doing now, is leading to a rolling chassis by summers end.

 

[tfeverfred]

So here are the dimensions off the Extended body frame we have fully assembled in the back.
All these are from the top of the main rail where it meets the 45* kick-up

To the back side of the 1.5"x 3" transmission crossmember = 21 5/8"

To the pedal pivot centerline of the master cylinder bracket = 41 1/2"
(down 2" from top of frame to C/L pivot)

To the center of the motor mount bracket on the frame = 63 3/4"
(down 5/8" from top of frame in front, tip downhill toward rear 3-4 degrees)

These dimensions are out of our fixture so our long body fitment will be correct.
There is room to go forward 1/2" on the motor and trans dimension if you want more clearance at the distributor and steering box but do not move the brake pedal bracket

Thank you! Sir, I owe you a dozen Tamales!

 

[RESINATOR]

Also, if you are going to run a 20" bed, the centerline of the rear-end/wheel will be around 11 1/4" back from that same point. This puts the wheel in the right place and makes the driveshaft a bit longer. ( if using the Sportdeck it would be 13 1/4")

 

[tfeverfred]

Exactly. An inch here or there changes everything, but in all those measurements, there has to be at least one constant that doesn't change. I my case, I think it's going to be engine mount to transmission mount. And since my reference point is the rear kick, everything falls into place with that variance you mentioned as a "given" or allowable tolerance. I dodn't think it's going to be that much.

I'm betting it's 65 3/16 from kick up to motor mount center. Give or take 1/4".

Dang..... about 1 1/2" off. Wonder where it went?

 

[tfeverfred]

Thanks, Resinator. I cleaned my frame rail and marked it off. It looks "right". My measurements and figure weren't off that much, but enough where it would have been an issue. Being able to install these brackets without an engine/trans mock up will be a time and labor saver. Thanks again.