Bucket seat hole size?

[DionR]

What size hole did the factory drill in the floor pan for bucket seats? The bench seat holes are huge, so not ready to assume they are the same size.

Thanks.

 

[YY1]

Studs are the same, and interchangeable.

 

[DionR]

Studs are the same, and interchangeable.

Right, and pretty sure they are 5/16" studs.

But did they drill 3/8 holes or something larger? The holes for the bench seat studs are bigger than that, but not sure what the factory did for the bucket seat studs.

 

[YY1]

Unless you drill them perfect (super hard to do), you want a little room to work with.

 

[DionR]

Unless you drill them perfect (super hard to do), you want a little room to work with.

Agreed. Just looking for what the factory did.

 

[413]

I have a 67 X bucket car here. a 7/16" bolt is loose. The nub on a fan spacer is too big to go in the hole.

Car has not been fooled with.

 

[DionR]

I have a 67 X bucket car here. a 7/16" bolt is loose. The nub on a fan spacer is too big to go in the hole.

Car has not been fooled with.

So maybe they did use the same size hole as the bench seat holes. I will have to check those closer to see how that compares. Thanks!

 

[413]

A Nice fit is a craftsman 1/4" drive 3/8" short socket, made in USA bought new in 1986.

Probably same size bench or bucket, makes it easy on the line,

 

[Dana67Dart]

I just measured my 67 Dart factory bucket seat car and I get between 0.50-0.60" so 1/2 - 9/16 the inner holes were closer to 1/2" the outer holes were closer to 9/16

 

[YY1]

I just hold drill bits up to the stud, and go with one size larger.

If I can't get all four studs through the pan, I go one more size up for two of them, usually the inboards.

Also be aware that some pans have a second set of outboard dimples because benches and buckets use different outboard hole locations.
66/67 B body cars do.

..also in the 80's they redesigned the supports and instead of using a brace on the floor for the inboard holes, they used a MUCH larger captive, toothed washer on the nut.
If you can find a set of those nuts, it's a good investment in strength vs pulling throug the floor.

 

[Oldmanmopar]

The correct hole size is already in the bracket coming off the rocker panel for the outer bolts under the car. Measure it . Also the inner floor plates needed to install bucket seats have the correct hole. I believe they are 1/2 inch to 5/8 inch. I have the plates if you need a correct measurement

Bucket Seat Floor Brackets - 67-76 Dodge Plymouth A-Body

 

[DionR]

Also be aware that some pans have a second set of outboard dimples because benches and buckets use different outboard hole locations.
66/67 B body cars do.

A-Bodies (at least the ‘67+ ones) have a fairly tall wedge riser for bench seats with their own set of holes. They can’t be used for OEM buckets at all and the buckets sliders sit inboard of those.

 

[DionR]

The correct hole size is already in the bracket coming off the rocker panel for the outer bolts under the car. Measure it . Also the inner floor plates needed to install bucket seats have the correct hole. I believe they are 1/2 inch to 5/8 inch. I have the plates if you need a correct measurement

Bucket Seat Floor Brackets - 67-76 Dodge Plymouth A-Body
View attachment 1716538379

Thanks. I was just curious if the factory used the same size or if they were different since the bench seat holes are pre-punched into the pan but the bucket seat holes have to be drilled on the assembly line.

Hmm…after typing that, I realize I am making an assumption that the pans for both bench and bucket seats were the same and bucket seat cars had the holes drilled in the pan somewhere along the way. Maybe that isn’t how it worked and the bucket seat holes were punched during the manufacturing of the pans and were specific to bucket seat cars.

 

[413]

It sure seems to me I put buckets in a bench car and used the same outboard holes from bench and drilled inboard holes at dimples in floor. 67 b-body.

 

[DionR]

It sure seems to me I put buckets in a bench car and used the same outboard holes from bench and drilled inboard holes at dimples in floor. 67 b-body.

Maybe in a B-Body, but not an A-Body. The plane the bucket seat risers sit on isn’t even remotely the same as the bench seat in an A-Body.

 

[DionR]

Here is an A-Body floor pan.

You can see the bench seat risers and the 4 holes for the bucket seats. Plus the reinforcement plates.

 

[72bluNblu]

Here is an A-Body floor pan.

You can see the bench seat risers and the 4 holes for the bucket seats. Plus the reinforcement plates.

Hey that floor pan looks familiar!

Also note this is an original bucket seat car and the bench seat holes are present and filled with rubber plugs. That was a factory deal, so the bench seat holes were likely punched in all of the floor pans regardless. At least in ‘71 I guess.

I can measure this car but it’ll be a couple days.

 

[DionR]

Hey that floor pans looks familiar!

Also note this is an original bucket seat car and the bench seat holes are present and filled with rubber plugs. That was a factory deal, so the bench seat holes were likely punched in all of the floor pans regardless. At least in ‘71 I guess.

I can measure this car but it’ll be a couple days.

Is that picture yours? I found it on the B-Body site just looking for an example to show.

One of the things that caught my eye is that my ‘73 Duster has a notch in the bench seat risers that isn’t in the floor pan shown above. I am using that notch to get my E30 Sport Seats lower and was surprised it wasn’t in the earlier pans.

No need to measure anything more. Pretty sure I have the info I need. Thanks, though.

Really just a curiosity, not something holding me up.

 

[Dana67Dart]

That was a factory deal, so the bench seat holes were likely punched in all of the floor pans regardless. At least in ‘71 I guess

same for my 67 dart factory bucket seat seat car

 

[72bluNblu]

Is that picture yours? I found it on the B-Body site just looking for an example to show.

One of the things that caught my eye is that my ‘73 Duster has a notch in the bench seat risers that isn’t in the floor pan shown above. I am using that notch to get my E30 Sport Seats lower and was surprised it wasn’t in the earlier pans.

No need to measure anything more. Pretty sure I have the info I need. Thanks, though.

Really just a curiosity, not something holding me up.

Yeah, it’s my ‘71 EL5 GT.

That’s interesting about that cut out in the riser, I never noticed that!

You can see it here on my ‘74, looks like they used it to route the wire harness

And then my ‘71 again