F Body Frame Connectors

Trivium91

Well-Known Member
Joined
Mar 31, 2020
Messages
60
Reaction score
8
Location
Canada
Hi Guys, i have a 1980 Volare with T-tops and i have a set of frame connectors however they appear to only weld to the front and rear sub frame and not the floorpans. Assuming im looking to get 400HP at the crank will these be suitable? They are basically square tubing from front to back, if its possible would it be advantageous to run a few weld beads to the floor pans wherever possible?
 

MiradaMegacab

Well-Known Member
Joined
Feb 27, 2011
Messages
1,847
Reaction score
753
Location
Long Island NY
BAD808EE-F5DF-4872-A0DB-BAC2A08AF462.jpeg

I’d use 2X3 rectangular 10gauge steel tubing. Pic is just for reference but you can drop the frame connector into the rear frame rail from the top and of course welding any frame connector to the floor will result in a stronger more rigid chassis.
Some good reading here, especially post#4.
drag set up for my aspen
 

Trivium91

Well-Known Member
Joined
Mar 31, 2020
Messages
60
Reaction score
8
Location
Canada
View attachment 39909
I’d use 2X3 rectangular 10gauge steel tubing. Pic is just for reference but you can drop the frame connector into the rear frame rail from the top and of course welding any frame connector to the floor will result in a stronger more rigid chassis.
Some good reading here, especially post#4.
drag set up for my aspen

Hmm, not really looking to do anything hardcore like that as its just for the street. Plus i've had passengers in the back seat before, lol. The frame connectors i have are designed to just weld to the sub-frames front and back under the floor pan. Im looking at 400HP tops at the crank so im not sure if anything hardcore is necessary. However, i already had the passenger side floor pan wrinkle a bit and a bump raised up behind the passenger seat (i fixed it with hammer). I suspect im running about 300HP at the crank now, i did measure from various points so it doesn't appear to have permanently twisted.
 

Duke5A

Well-Known Member
Joined
Apr 6, 2018
Messages
1,640
Reaction score
855
Location
Michigan
Hi Guys, i have a 1980 Volare with T-tops and i have a set of frame connectors however they appear to only weld to the front and rear sub frame and not the floorpans. Assuming im looking to get 400HP at the crank will these be suitable? They are basically square tubing from front to back, if its possible would it be advantageous to run a few weld beads to the floor pans wherever possible?

My Dad's car is an 80' Diplomat coupe with T's pushing 450 crank horse. You'll be fine just connecting the front and rear rails. That is how both Dad's and mine are installed. Yes, the correct way is through the floor, but for ease of installation it is still a night and day difference.

If you want a bit more than that add a cross brace between the ties with a built-in loop for the driveshaft right behind the transmission tail housing.
 

Trivium91

Well-Known Member
Joined
Mar 31, 2020
Messages
60
Reaction score
8
Location
Canada
My Dad's car is an 80' Diplomat coupe with T's pushing 450 crank horse. You'll be fine just connecting the front and rear rails. That is how both Dad's and mine are installed. Yes, the correct way is through the floor, but for ease of installation it is still a night and day difference.

If you want a bit more than that add a cross brace between the ties with a built-in loop for the driveshaft right behind the transmission tail housing.
Awesome, yeah i guess the connectors i have are not designed to go through the floor....they are designed to weld right up underneath it. If i can tack weld a few lower spots of the floorpan it would be a bonus.
 

Oldiron440

Well-Known Member
Joined
Apr 25, 2017
Messages
3,048
Reaction score
738
Location
Iowa
If your not running slicks at a dragstrip you don't need frame connectors...........
 

Trivium91

Well-Known Member
Joined
Mar 31, 2020
Messages
60
Reaction score
8
Location
Canada
If your not running slicks at a dragstrip you don't need frame connectors...........
i would disagree, as mentioned i wrinkled my floor pan behind the passenger seat from the torque twist and im running about 300Hp at the crank if i were to guess with a 3.91 rear end. I think its just the unibody twisting which wrinkled the floor pan a bit, i straightened it with a hammer. Any more power and and i could twist the whole car permanently...thats why im putting in SFC's. I dont have true slicks just performance tires but they grip fairly well.
 
Last edited:

Oldiron440

Well-Known Member
Joined
Apr 25, 2017
Messages
3,048
Reaction score
738
Location
Iowa
There must be other problems because I didn't have problems until I went to the strip with over 500hp and slicks. The general rule is you don't need them unless you can apply the power, 300 crank hp I wouldn't bother.
 

Rattle Trap

Well-Known Member
Joined
Feb 10, 2013
Messages
147
Reaction score
45
Location
The Outer Limits
T-bar cars can be very flexible. I don't blame you one bit for tying the rails together. 77's used to spit the driver side tops on the ground from body flex. Surely that's why they redesigned the whole t-bar. I was looking at a similar idea to the photo over the weekend. But with 2x2 Over the rear floor pan and right inside the rear rails. Rear passengers will just have to deal with it. Cmon, it's only about like having a water bottle on the floor back there. I'm figuring along with cutting the rear section of my front floor out for them to pass forward on the same plane, that it will provide access to cut my trans crossmember out. Fold the cuts for weld tabs internally, and shove that tubing right up inside my front rails too. I picked up an old but low miles MP 360/380hp iron head crate engine and want to put that to the wheels instead of twisting the chassis.
 

Trivium91

Well-Known Member
Joined
Mar 31, 2020
Messages
60
Reaction score
8
Location
Canada
No other issues the car is pretty clean...unless that was there from the factory where the floorpan is but i doubt it. When i do a brakestand you can actually see the frame twist a bit and the passenger front side raise up slightly. I do have a 3800 stall and 3.91 gears with a built up tranny, maybe thats why? I dont think its necessary to cut the rear floor pans. The frame connectors came with the car when i bought it they were just not installed, i suspect they are 12 years old but they are designed to weld just under the floor pan and only to the frame connectors. Perhaps the geometry of having it cut right through the floor pans might be marginally better for rigidity but unless im building a drag car i dont think it matters...anything will help me at this point. In contemplating taking the car in to get them welded since i have to run a generator to get the welder going, i also dont have a lift i would need to build blocks. Not that its a hard weld its been at least 5 years since i welded last.
 

Oldiron440

Well-Known Member
Joined
Apr 25, 2017
Messages
3,048
Reaction score
738
Location
Iowa
If your going to put in frame connectors through the floor is the correct way, I use 2" 1/8 wall tube and it's far superior to the crap you weld to the bottom of the car. You go back inside the subframe at each end and connect with a solid tube tieing in the floor the entire length.
Two inch connectors will cost little more than one inch of intrusion on the floor.
 

Duke5A

Well-Known Member
Joined
Apr 6, 2018
Messages
1,640
Reaction score
855
Location
Michigan
Frame ties make a world of difference in even a factory powered car. These bodies were wet noodles even when new and age hasn't helped. After I installed mine with normal street driving you could feel the difference just changing lanes. If I ever build another M, or even just own one, it'll get ties even if it I keep it a 318.
 

Rattle Trap

Well-Known Member
Joined
Feb 10, 2013
Messages
147
Reaction score
45
Location
The Outer Limits
No other issues the car is pretty clean...unless that was there from the factory where the floorpan is but i doubt it. When i do a brakestand you can actually see the frame twist a bit and the passenger front side raise up slightly. I do have a 3800 stall and 3.91 gears with a built up tranny, maybe thats why? I dont think its necessary to cut the rear floor pans. The frame connectors came with the car when i bought it they were just not installed, i suspect they are 12 years old but they are designed to weld just under the floor pan and only to the frame connectors. Perhaps the geometry of having it cut right through the floor pans might be marginally better for rigidity but unless im building a drag car i dont think it matters...anything will help me at this point. In contemplating taking the car in to get them welded since i have to run a generator to get the welder going, i also dont have a lift i would need to build blocks. Not that its a hard weld its been at least 5 years since i welded last.

Like said above. A stock engine will twist them. I used to enjoy how they'd lift a little just from a 360 revving in neutral at a light. Today not so much. When they cut half the roof out and they were just asking for trouble with this platform.

I don't have enough power to my garage for the welder either, yet. Poor Boy syndrome. I've been using a generator for the past 15 years for it. Not too poor to take care of things that are really important, like having freezer and sump pump power after a big storm.

Run ya some test welds to refamiliarize yourself and weld er up! Whether you're happy to use manufactured connectors or really want to dig into this, you won't regret having done 'something' about body flex.
 

Trivium91

Well-Known Member
Joined
Mar 31, 2020
Messages
60
Reaction score
8
Location
Canada
Like said above. A stock engine will twist them. I used to enjoy how they'd lift a little just from a 360 revving in neutral at a light. Today not so much. When they cut half the roof out and they were just asking for trouble with this platform.

I don't have enough power to my garage for the welder either, yet. Poor Boy syndrome. I've been using a generator for the past 15 years for it. Not too poor to take care of things that are really important, like having freezer and sump pump power after a big storm.

Run ya some test welds to refamiliarize yourself and weld er up! Whether you're happy to use manufactured connectors or really want to dig into this, you won't regret having done 'something' about body flex.

yeah my generator is on the fritz, i suspect too many people started the generator with a load and burned up the voltage regulator as its not putting out power....something else to fix...or run a new circuit to my attached garage whichever is less work i guess. On second thought...I think im just going to have a mechanic i know weld them in on the alignment rack for $150. Perhaps he can tell me if the car is twisted already based on the laser from the machine at no charge. Furthermore, he has built a few drag cars so his insight to extra modifications might be worth it anyways.
 

LSM360

Well-Known Member
Joined
Nov 28, 2011
Messages
812
Reaction score
314
Location
Melbourne, Florida
That's the link that Silverd1973 just posted ^ and they say "backordered"

Does anyone know if they fit 4 door cars too?
 
Back
Top