Hot Rods I'M GOING TO BUILD AN ALTERED.

I'll have a mid-plate, and side mounts on the block. Already planning to have a factory rubber mount under the trans tailshaft just for the reason you said.
-Brad

 

In addition to the rubber mount I like to "cantilever" the mount by moving the crossmember further rearward and mounting the trans to a little 'diving board' or 'tongue depressor' moly steel plate so it has a little give to it .

 

I never bother with a trans mount at all if the car has front and mid plates. If the motor is going to be removed from the car the trans is usually coming with it or is already out. I keep the space under the transmission clear so that it can come out the bottom if the car is up on the jacks. I also make the steering cross member removable so that it is easy to get the trans out the top as well. Anything that makes the car easier to work on is a plus.
Remember that in the factory installation the entire package is hung from a couple of side mounts near the front of the block and the trans mount so the trans itself should be strong enough to hang off the back of the block without any additional support.

Roo

 

I've talked to a bunch of people about a trans mount--guys I trust say a PowerGlide is fine to hang out in space, but I'm running a C6, so it'll be loooong, and needs a rear mount.

 

I thought of a couple more reasons why a trans mount may be useful:

1. In the event of a driveshaft failure that flailing shaft could really do a number on the unsupported transmission - maybe even rip it apart at the bellhousing. To that end NHRA mandates "anti-blowback" devices on dragster transmissions - essentially bars to triangulate the position of the transmission in the chassis.

2. You suffer a violent flex plate or torque converter explosion. It shatters the bellhousing area of the 'Glide. What keeps the transmission from flying back into your lap? (And by 'lap' I mean 'b*lls') The shifter cable?

 

And maybe we should cover the whole car with .250 Titainium in case a small meteor falls from the sky and lands on the car

 

...or bury our heads in the sand.

 

I will not respond anymore because this build post is getting off track---Sorry

anyone can PM me with questions on proper build techniques based upon 30 years of hands on expirence.

 

jeezus Don...I go away for a short while and all hell breaks loose

 

1. The driveshaft should be contained by the required loops/shields if it is a u-joint style and the splined coupler style has no inertia so the chance of either breaking the transmission is slim to none. The anti blowback bars required by the rules are for the bellhousing in clutch equipped cars, not for the transmission.

2. About the worst than can happen with a flex plate is the the ring gear may break (highly unlikely but it has happened) and like the splined driveshaft it does not have enough mass to do any more than maybe pierce the bellhousing. The worst that is likely to happen to a torque converter is that it may balloon. Most broken bellhousings that I have seen were the result of too many rigid mounts in a flexible chassis. Lets assume the worst case, a massive explosion that does destroy the bellhousing area. I would suggest in that case that the extension housing would also be a victim if it is rigidly mounted to the frame and if it is rubber mounted I don't like the chances of the mount surviving that sort of explosion. In an altered the trans would either hit the steering cross member if it was thrown upward or go under the seat if it went backwards and in a front motor dragster it would hit the rear end before it could get to the driver (in both cases the feet and legs are more vulnerable than the driver's nuts as they are in closer proximity to the trans.

I am with Bruce, lets get back to watching Don build his car.

Roo

 

I agree. Let's agree to disagree. Sorry to wander off topic.

 

just one more note. remember he is building a 11 sec or slower car. according to how high the rpm is, 11 seconds doesn't hit as hard as a faster car does. it is also a light car. my brothers car has rubber mounts all around and it is a 11-0's car we haven't had any problem with it. we have ran it for about 8 years.

 

Suspension work is looking good Don, I have not been on for a while (dealing with all this wonderful weather on my farm) ,
With regard to the rear trans mount, I run a rubber one in our altered , had it in before we added the mid plate, I agree with Rooman it is overkill, but i left it in, if it is worth anything I ran all my dragsters both front and rear motored with no rear mount and never had any issues , keep up the good work
Paul

 

Hey, Paul, been wondering if you were still here or back home. Look forward to shooting the breeze with you again sometime.

Dan and I spent the other night revamping the rear suspension layout, and think we finally have it worked out. It is much better and more streamlined. I am not going to post any more pictures until it is much further along because it is hard to understand unless you are there looking at it directly.

Don

 

Don,
You better post some pictures or something. The last time you took a break all hell broke loose!

 

Looking great old chap, send my regards to Dan, it's been a long time no see

 

Ok, here is a quick picture of where we are right now.



Hi Steve ! Dan is up to his old tricks. He went to the shop the other day, supposedly to work on his Mustang, but he spend the day welding up the rear section of my altered. I was surprised when I walked in the shop the next day.
Say hello to Sue, as well.

Don

 

Looks like the rear section was raised an inch or so compared to the earlier pictures. Looks great. Nice of your son to take the time to help you out. Got to be a great kid.

 

Yep, it is about 2 or so inches shorter on the bottom. I was originally keeping the bottom hole of that frame bracket empty so I could put the wishbone in there, but I have decided to relocate the wishbone to the lower round crossmember we have yet to install.

My Sons take good care of the old man for sure. I thought Dan was working on his own car all day Friday, but he was actually working on mine. Kinda like having my car built on Overhaulin' .

Don

 

I haven't had any updates to do lately, but yesterday Dan and I were off work and decided to finally get the main frame rails welded up. You guys will remember that we were wrestling with how to make the part of the frame that holds the front part of the 4 bar setup not stick down so far. Well, Dan came up with a very workable solution that pretty much eliminated the problem.

What we did was move the front part of the frame down a few inches and move the rear section up a bit. Then we made a tapered section at the rear of the front portion so that it flows into the upright tube a little better. It is much cleaner, and a lot of you suggested something similar. I didn't think it was possible because the lower bar sits so low, but this solution actually did work. Here is a picture of the final frame rail design:



It looks a little spindly now, but the entire roll cage will be tied into it, and we are going to put more tubes into that cage than even NHRA requires. We also decided to go with a 2.5 inch rear crossmember to make tying the roll cage into it a little easier. We slipped the body on and as you can see very little sits below the body now.



We put in about 12 hours yesterday, but it feels good to get to this point. Now we can put it on the jig, weld in the crossmembers, and then install the rear suspension.

Don

 

Don, are you going to put some plates where the straight rails transition to the tapered section at least on 3 sides but leaving the outside frame rail flat ?

 

Looks great Don.

 

Oh yeah ! We are going to have Ron at RPM cut us some neat plates to put over EVERY joint and then Dan is going to fully tig around each one. We will put them on both sides of the rails. He slipped backer plates inside every joint before he welded it so that he could burn a hot, deep weld into each one, but the extra gussets will be some insurance. There will also be a tube crossmember going between each rail and that will have more tubes going to the side rails.

The cage is also going to incorporate tubing that will run from that kickup to the front cowl bar and be gusseted. Won't be the lightest drag car ever built, but I want it strong in case I ever end up going into a cornfield at the end of the strip !

Thanks, Mikey.

Don

 

I knew you guys would do the right thing, and you went above and beyond.

 

What always amazes me is that it takes so long to get to that final welding stage. Seems that you should be able to do that in a couple of hours but it always takes more time, usually a lot more!

 

You are so right !! Yesterday we got at the shop about 3 pm and it took us until about 11 before all the pieces were ground clean and prepped for welding, then we welded until about 3 am. That is why we only build cars for ourselves, we couldn't charge anyone for all the time it takes to do the most simple fabrication job.

Don

 

Welder's lament:

"What! You are charging me that much! You were only welding for 20 minutes".

Yes, and 90 minutes of prep and setup before that. Who should pay for that?

 

^^^^^^

 

Don. The frame looks great. Nice work.

 

Any updates on the build? I'm looking forward to some progress pic.