Possibly Stupid Vintage NASCAR Question

[Snake45]

Were '60s NASCARs required to run full frames? Specifically, did they have to extensively modify the MOPARS and Fairlanes/Cyclones, or did they just run them as unibodies? 

[Dave Van]

No one answer.......in the 60's NASCAR still required the race car be based on the street version. So if car had full frame so did race car. Then in the 70's they started the 'generic'  chassis where the car used a full frame and had to have the same TYPE suspension as street but could be fabbed or cross bread. (GM truck trailing arms on a Torino) Cars like a 67 Fairlane would start as a stock version and be modified into a racer. IIRC they could connect the sub frames but could not fab a full tube frames as they did 70's. 

The real experts are on Randy Ayers Forum....

[DoctorLarry]

Snake: Here is a photo from the 1973 NASCAR Handbook on chassis construction for unit body cars:

[Snake45]

Thanks! I asked because some time ago, I read something to the effect that starting in the mid '60s, "everybody" was running 1965 Ford frames--presumably full-size/Galaxie frames, presumably modified to fit shorter wheelbases as necessary. I wasn't sure if the comment was a joke, or had some basis in truth, and if so, was it mandated by NASCAR, or just something everyone did, or what. I'd never really thought about it before, and that at that time, all the intermediate cars except GM's (which wasn't a big force in NASCAR by then) were unibodies. 

[DoctorLarry]

Keep in mind that picture was in 1973, so as Dave said it may have been more of a free for all in the 60's.

[yellowsportwagon]

10 minutes ago, Snake45 said:

Thanks! I asked because some time ago, I read something to the effect that starting in the mid '60s, "everybody" was running 1965 Ford frames--presumably full-size/Galaxie frames, presumably modified to fit shorter wheelbases as necessary. I wasn't sure if the comment was a joke, or had some basis in truth, and if so, was it mandated by NASCAR, or just something everyone did, or what. I'd never really thought about it before, and that at that time, all the intermediate cars except GM's (which wasn't a big force in NASCAR by then) were unibodies. 

From 66-68 or 9 Holman Moody cars used a 65 Galaxie frt stub. Firewall forward. After 69 it was fabbed copy of a 65 galaxie. This same design was grafted to the frt of full frame cars too starting in 71. Along with the beginnings of the truck arm rear suspension.It would be done like this.

Edited May 11, 2020 by yellowsportwagon

[DoctorLarry]

Here is the 1973 NASCAR Handbook for full frame cars:

[DoctorLarry]

Both photos are on the Cotton Owens' Garage web site. There are also photos of the harness and fuel cell as well.

[gtx6970]

As far as I know , the type of chassis / or chassis mods  depends A LOT on manufacturer.

 

This is the original Petty Bird, sans exterior sheet metal and paint

As you can see its a heavily modified / re-enforced factory floor pan and a shop built front suspension/stub frame setup

 

[Snake45]

Very cool, thanks! 

[THarrison351]

I'm no expert, but in the '60s almost all the cars were running full frames. When the mid-size Ford was included to run in 1966, I believe Bud Moore ran a Comet without a full frame for some of his cars. Soon thereafter NASCAR allowed him and the other Ford teams to use a Galaxie clip up front with the rest fabricated/welded to the existing unibody.

https://www.hotrod.com/articles/up-close-with-the-1966-mercury-comet-nascar-race-car-of-darel-dieringer/

[yellowsportwagon]

Yes Bud Moore ran a couple shock tower Comets. Problem was fitting and working on a 427 in that small engine bay. That’s when H/M came up with the narrowed Galaxie clip. It was a front frame section with tubes that slid into the existing rocker panels.

[Snake45]

Good info, thanks everyone! (I'll bet I'm not the only one who learned something here.) 

[GLMFAA1]

I am no NASCAR know it all but I had a friend that was and he always mentioned something about front and rear steer front suspensions where the steering box is either ahead or behind the front wheels. Could this be the reason for using the front clips?

greg

[yellowsportwagon]

54 minutes ago, GLMFAA1 said:

I am no NASCAR know it all but I had a friend that was and he always mentioned something about front and rear steer front suspensions where the steering box is either ahead or behind the front wheels. Could this be the reason for using the front clips?

greg

No all Ford cars back then were rear steer. I think guys got used to the way they handled so that brought on the wide spread use of them on just about everything in the seventies.

Edited May 12, 2020 by yellowsportwagon

[Ace-Garageguy]

3 hours ago, Snake45 said:

Good info, thanks everyone! (I'll bet I'm not the only one who learned something here.) 

Agreed. Good stuff I didn't know.

[yellowsportwagon]

Sometime in the mid seventies builders were allowed to fab the whole frame.Prior to that they had to keep the factory side rails. Heavily modified as they were. Chrysler cars never used the 65 Galaxie derived clip because they had Torsion bar frt suspension . Car had to be sprung like the factory car it represented. In other words coils where coils came factory. Leafs where they came and Torsion bars where they came. The few Chryslers built in the eighties went to the common four coil chassis as NASCAR changed its rules.

[RancheroSteve]

There's a chapter in Bill Coulter's book that covers building a "half chassis car":

Half Chassis

[afx]

7 hours ago, RancheroSteve said:

There's a chapter in Bill Coulter's book that covers building a "half chassis car":

Half Chassis

This is a great book, I highly recommend it.

[Snake45]

Interesting, thanks! 

[afx]

Starting on page 4 of Coulter's book there is a timeline of the evolution of the cars up to 1997.  For 1967 is says: "Stock production-based frames were no longer required. Teams could build fully fabricated frames that resembled a stock frame for safety reasons."

Edited May 20, 2020 by afx

[yellowsportwagon]

30 minutes ago, afx said:

Starting on page 4 of Coulter's book there is a timeline of the evolution of the cars up to 1997.  For 1967 is says: "Stock production-based frames were no longer required. Teams could build fully fabricated frames that reassembled a stock frame for safety reasons."

I’m sure this is incorrect. A portion of the stock frame had to be in place well into the seventies. The front frame on a half chassis car couldn’t be completely fabbed until 69-70. Not all books are correct. Much has been learned through period photos too. The photos are never wrong.They show it as it really was.

[afx]

3 hours ago, yellowsportwagon said:

I’m sure this is incorrect. A portion of the stock frame had to be in place well into the seventies. The front frame on a half chassis car couldn’t be completely fabbed until 69-70. Not all books are correct. Much has been learned through period photos too. The photos are never wrong.They show it as it really was.

Not trying to start an argument, only a discussion so we can all learn.  I respect your knowledge and your great NASCAR builds.  NASCAR.com indicates: 

GENERATION 2: 1967-1980

-Stock body with a modified frame.
-Modified chassis became part of the spot with Holman-Moody, Banjo Matthews and Hutchenson-Pagan building chassis for teams.

1967 FORD FAIRLANE

-Due to unibody construction on the stock vehicle, NASCAR allowed purpose built race chassis for safety.

 

https://www.nascar.com/gallery/the-evolution-of-nascar-sprint-cup-cars/#photo-1

Edited May 20, 2020 by afx

[RancheroSteve]

8 hours ago, afx said:

1967 FORD FAIRLANE

-Due to unibody construction on the stock vehicle, NASCAR allowed purpose built race chassis for safety.

I think in this case "purpose built" could be ambiguous and doesn't necessarily mean "fully fabricated". I take it to mean that in '67 they were using Fairlane unibody platforms, with Galaxie front clips, and of course a lot of rollbar tubing and boxing in of the frame rails, like Coulter shows in his book. At some point I suspect they started running out of actual '65 Galaxie frames ('69-70?) and started making something virtually identical that could be essentially be called "fully fabricated". Then I imagine as time went on, they began using less and less of the original unibody until it became a fully fabricated chassis. The way they were cutting up and modifying the unibodies made them almost irrelevant anyway. What year this happened, I'm not sure (the sixties and early seventies cars are more my cup of tea.)

Again, like afx, I'm not trying to start an argument, that's just kinda how I read the history.

Edited May 21, 2020 by RancheroSteve

[yellowsportwagon]

18 hours ago, afx said:

Not trying to start an argument, only a discussion so we can all learn.  I respect your knowledge and your great NASCAR builds.  NASCAR.com indicates: 

GENERATION 2: 1967-1980

-Stock body with a modified frame.
-Modified chassis became part of the spot with Holman-Moody, Banjo Matthews and Hutchenson-Pagan building chassis for teams.

1967 FORD FAIRLANE

-Due to unibody construction on the stock vehicle, NASCAR allowed purpose built race chassis for safety.

 

https://www.nascar.com/gallery/the-evolution-of-nascar-sprint-cup-cars/#photo-1

Exactly but the rear frame rails were still intact. It was modified not fully fabbed. Per the rule books portions of the factory frame were still required into the seventies. Look at how Juniors early Montes were built. Or Bobby Allison’s cars. Modified stock frames. HM frt stubs were allowed on those cars too. Allison preferred frt steer GM based front ends.