Gasser class designations

[smhardesty]

I was just reading over some older threads and read the '58 to '68 NHRA rule books. Those are pretty darned neat. It brought to mind a question I've had for a while. I'm a real gasser nut and have several in my stash to eventually build. I know that gasser class designations changed at least a couple times over the years they ran. I'm wondering how many guys would notice whether or not the class letters on the car/windows was correct. Other than obvious GS - Supercharged classes, how many would really know if a car was truly an A/G or a C/G? The reason I'm asking is that I'm not one to recreate a specific 1:1 car. I'll build the car, then find just a few decals to apply and a lot of my builds will have very few decals. So how important is it to try and get the letters exactly correct? Of course things get even more complicated when you throw in the changes in class made over the life of gasser racing.

[Straightliner59]

That depends a lot on the builder. For me, it's very important, because I am completely anal-retentive about such things!grin It's so easy to figure it out, too. I just "Google" "Curb weight of (insert make/model here), then divide by the displacement of the engine I'm using. Done deal! The same formula can be used for virtually any "class racer". Just my $.02.

 

[larman]

I have seen plenty of drag models that are clearly classed wrong. For me, I try to follow the NHRA/AHRA rule books for specific years on my builds. I guess it is in the same vain as do you want  correct plug wire order? Do you want authentic colors? Equipment? Everyone builds for different reasons, so I guess it wouldn't bother a lot of people. However, I tend to recognize it when it is wrong and I think there are quite a number of drag builders who woud also. 

Edited August 9, 2017 by larman

[Alan]

I too am a stickler for correctness and attention to detail, as in what detail to what ever level is done, is accurate and correct.

Alan

[High octane]

A lot of builders use /GS designation even though the engine is not supercharged, and this is wrong.

[Daddyfink]

Yeah, some folks just like using the letters on the decals sheets. I have seen AA/FA on a door slammer. Yup, kinda off a bit. 

[iBorg]

If I judge, and have a couple of times, the wrong designation would effect my decision. A gasser has a stock based or rectangular frame. Period. A round tube frame throws the car into an altered class. Likewise a mid 60's funny car would not car the AA/FC tag. That came about in either '70 or 71. No pre '68 car would be a pro stock. That class came about in 1970 and allowed two year old cars to compete. The gasser tags are a bit harder. NHRA changed those through out the 60's. Likewise a modified sports car was moved into gasser or altered depending on the frame in the late 60's. 

Rivet counting? Maybe, but why spend hours to super detail an engine and have such a simple faux pas.  

[smhardesty]

OK. So obviously the consensus is that the body/window class designations ARE important. I'm going to have to decide on each build if I'm going to attempt to replicate a period racer and if so, what period it is to be. Either that or I need to decide to make each of my gassers current and present time drag cars.

Thanks for all the replies! Helped me out a lot.

[Snake45]

Gas designations aren't that hard. It's based on cubic inches vs weight. Big engine/small car? Most likely A/G. Small block in something like a '55 Chevy? Could be B, C, or D/G depending on how many cubes and how much the car has been lightened. Make a weight guess, do the math, check the rulebook. It ain't rocket surgery.

[Tedly]

 in the mid to late 70's A/G was 5.50 pounds per cube, B/G 6.50 C/G 7.50 D/G 8.50 E/G 9.50

[waynehulsey]

Gas designations aren't that hard. It's based on cubic inches vs weight. Big engine/small car? Most likely A/G. Small block in something like a '55 Chevy? Could be B, C, or D/G depending on how many cubes and how much the car has been lightened. Make a weight guess, do the math, check the rulebook. It ain't rocket surgery.

One other thing, depending on the period you're building, is that some bodies weren't allowed such as Anglia's in GS during the early years. The short wheelbase, high horsepower engine combos were considered too unstable until suspension and tire combos caught up with hp. I remember all the hassles Brad Anderson went through getting his Opel GT certified.

[Alan]

Gas designations aren't that hard. It's based on cubic inches vs weight. Big engine/small car? Most likely A/G. Small block in something like a '55 Chevy? Could be B, C, or D/G depending on how many cubes and how much the car has been lightened. Make a weight guess, do the math, check the rulebook. It ain't rocket surgery.

Me thinks you gotst  rocket science and brain surgery muddled a tad lol

[Snake45]

Me thinks you gotst  rocket science and brain surgery muddled a tad lol

I said exactly what I meant.

[6bblbird]

 

 Click on this: A Brief History of the Gasser Classes

All you will ever need to know about gas classes.

WF

 

Edited August 11, 2017 by 6bblbird

[smhardesty]

 

 Click on this: A Brief History of the Gasser Classes

All you will ever need to know about gas classes.

WF

 

I have that web page bookmarked and have read it a few times now. It's one of the better explanations I found on the 'Net that at least tries to explain the changes over the years.

Several of you guys have pointed out the basic premise that it's weight to cubes to determine the class. On a 1:1 car that would be no problem. What I see that can't really be certain on a model car is the exact weight of the car. There is no way to tell for sure on a model if the fenders are steel or fiberglass, and then there are other "hidden" factors in a model that would be obvious on a 1:1 car. Then, throw in the changes to class over the years and things can be a little different again. That's really why I was asking how closely anybody pays attention to the class letters on the body/windows. If I did a build and was trying to replicate a specific car from a specific time period there would be little argument about what letters should be posted on the car. but if I just built a '41 Willys with a non-supercharged engine, there COULD be questions about the true weight of the car and what time period it was supposed to represent.

Did that make any sense? Sometimes it's just really hard to explain things the way you have it in your head.

 

[waynehulsey]

Having done a lot of judging during the 70's up to 2000, I always looked for overall consistency. In as far as I could tell from looking (and within the limits of my knowledge) did the type of engine and the equipment on it match with the rest of the chassis and driveline. If it was supposed to be a early 60's style, things like the rear suspension setup, no wrinkle walls, roll bar and not a full cage. If it was carbureted, no double pumpers on a high rise. Movie example: American Graffiti 2 at the drag strip when the dragsters were running. It was supposed to be around 1964 (?) and the one dragster in particular was a econo dragster with a if I remember right Moroso valve covers, Powerglide and using a high riser with a big Holley on it. I remember my brain just spun when I saw that. Anyway just a few free thoughts (take'em at what they're worth).

[Reegs]

One other thing, depending on the period you're building, is that some bodies weren't allowed such as Anglia's in GS during the early years. The short wheelbase, high horsepower engine combos were considered too unstable until suspension and tire combos caught up with hp. I remember all the hassles Brad Anderson went through getting his Opel GT certified.

- The AHRA allowed short wheelbase cars (f'rinstance: Skipper's Critter).

- For a starting point on weight: http://www.conceptcarz.com/view/make.aspx

- Since we're making believe anyway, guesstimate what the weight savings would be re: fiberglass fenders, etc. Same with cubic inches.

[Ace-Garageguy]

...Several of you guys have pointed out the basic premise that it's weight to cubes to determine the class. On a 1:1 car that would be no problem. What I see that can't really be certain on a model car is the exact weight of the car. There is no way to tell for sure on a model if the fenders are steel or fiberglass, and then there are other "hidden" factors in a model that would be obvious on a 1:1 car. Then, throw in the changes to class over the years and things can be a little different again. That's really why I was asking how closely anybody pays attention to the class letters on the body/windows. If I did a build and was trying to replicate a specific car from a specific time period there would be little argument about what letters should be posted on the car. but if I just built a '41 Willys with a non-supercharged engine, there COULD be questions about the true weight of the car and what time period it was supposed to represent.

Did that make any sense? Sometimes it's just really hard to explain things the way you have it in your head.

Everything you said makes perfect sense. And your reasoning is why I almost always have a plausible backstory for anything I build.

I almost never do models of specific cars, but I like to do what-ifs that get the tech right for the period and applicable class the model is supposed to represent.

But there are a fair number of people who just don't care (and wouldn't catch AA/GS on a normally-aspirated Pinto four-cylinder ). We've had several 'discussions' of realistic gasser stance, for instance, with a few getting quite belligerent while arguing the opinion that these are just "toys", and that trying for technical and historical accuracy only takes the "fun" out of the hobby. I personally enjoy taking the extra effort to make a model believable and mostly technically correct, and consider it to be part of the "fun".

PS. A thought about fiberglass panels...they wouldn't necessarily change the class a car would run in. A 'glass nose on a gasser, for instance, would have two effects. It would reduce the total weight of the car, naturally, but the idea isn't to go into a higher class. Rather, it's to get as close to the minimum weight for a particular class as possible. Getting weight off the front is the other point, so that the car could be ballasted up to minimum class weight (if necessary) with the ballast placed where it would do the most good for weight-transfer during acceleration.

PPS. A further thought on other "hidden factors". For one example, the engine in the old Revell Stone-Woods-Cook Willys gasser represents a gen-one Olds OHV V8, introduced in 1949 and built through 1963. The engines came from the factory in displacements of 303, 324, 371 and 394 cubic inches, and all of them are visually almost identical...especially in 1/25 scale. A bored and stroked 394 can easily exceed 400 cubic inches, so obviously, for what appears to be the same engine, you could be in at least two different classes, depending on internal displacement. Again, that's why I usually build to a plausible backstory.

Edited August 12, 2017 by Ace-Garageguy

[Ace-Garageguy]

A little reminder of how much fun gassers are.

[waynehulsey]

- The AHRA allowed short wheelbase cars (f'rinstance: Skipper's Critter).

- For a starting point on weight: http://www.conceptcarz.com/view/make.aspx

- Since we're making believe anyway, guesstimate what the weight savings would be re: fiberglass fenders, etc. Same with cubic inches.

I think it was 1968 when NHRA finally allowed the short wheelbase, blown cars. It hadn't been too long before when NHRA had their Nitro ban. AHRA seems to have always been a bit loose about what they allowed at least from an NHRA viewpoint. But with AHRA's growth, IHRA, NASCAR even starting a drag association, plus independents finally NHRA had to do a bit of backtracking on their 'safety rules'. Having pretty much always been a NHRA man, never did understand all of AHRA class breaks especially in stock with all those option classes. Then as NHRA started getting into all the SS/GT, MS, FI classes plus the Econo and Bracket categories sort of lost track, then interest, with them.

[smhardesty]

Bill,

Your explanation kind of hits the nail on the head. A lot of what you said is exactly what I was trying to say. Mostly stock engines versus a bored and stroked engines that look like multiple 1:1 engines, uncertainty of weight, etc, etc, could make a difference of 2 classes or more. Then add in the various changes that were made to gasser classes over the years and the class designation on the car COULD be different.

By the way, thanks for that video. THAT'S real racin'.

[Reegs]

I think it was 1968 when NHRA finally allowed the short wheelbase, blown cars. It hadn't been too long before when NHRA had their Nitro ban. AHRA seems to have always been a bit loose about what they allowed at least from an NHRA viewpoint. But with AHRA's growth, IHRA, NASCAR even starting a drag association, plus independents finally NHRA had to do a bit of backtracking on their 'safety rules'. Having pretty much always been a NHRA man, never did understand all of AHRA class breaks especially in stock with all those option classes. Then as NHRA started getting into all the SS/GT, MS, FI classes plus the Econo and Bracket categories sort of lost track, then interest, with them.

The AHRA always tried to get everybody into the show, hence all those stocker breakdowns. They seemed to know what the fans "between the coasts" were lining up to see.

Oh, and the stock classes were a snap to figure out - if you brought a slide rule. 

[larman]

You are absolutely right that there is some leeway in scale with motor internals, weight, etc. I think the point of most of the comments  above is it is noticeable if the model is a C/G car with a naturally aspirated small block Chevy and has an A/GS designation on it.

[Snake45]

It's worth noting that A/GS, AA/G, and AA/GS all seem to mean the same thing at different times--it's the top class, supercharged. And I've seen all three definitions on similar (real) cars. A/G, on the other hand, is the top class UNblown. (And the same holds for the B and C weight breaks. I don't think the supercharged classes went lower than CC.)

[Reegs]

It's worth noting that A/GS, AA/G, and AA/GS all seem to mean the same thing at different times--it's the top class, supercharged. And I've seen all three definitions on similar (real) cars. A/G, on the other hand, is the top class UNblown. (And the same holds for the B and C weight breaks. I don't think the supercharged classes went lower than CC.)

A/GS, the 'S' denoting supercharged. Then the NHRA standardized the class designation along the lines of other supercharged classes and it became AA/G. The fans and teams complained so it became AA/GS.

Edited August 13, 2017 by Reegs