GT Classification Worksheet - Page 2

Ryck Campbell · 12-02-2014, 08:30 PM

Fire Sale,

If you car is a convertible then 3369 is correct. If not then 3267 is the shipping weight to use. With the engine rated at 335 the your non convertible would run C @3185 or D @ 3350 or E @ 3520. A convertible would run C @ 3285, D @ 3350, E @ 3520 or F @ 3685. These weight are class minimums. The convertible can't get to the top of C and would have to run 100 heavy for the class.

FireSale · 12-02-2014, 09:14 PM

Quote:

Originally Posted by Ryck Campbell

Fire Sale,

If you car is a convertible then 3369 is correct. If not then 3267 is the shipping weight to use. With the engine rated at 335 the your non convertible would run C @3185 or D @ 3350 or E @ 3520. A convertible would run C @ 3285, D @ 3350, E @ 3520 or F @ 3685. These weight are class minimums. The convertible can't get to the top of C and would have to run 100 heavy for the class.

It's a GT build. A 68 Mustang coupe using the engine specs of the 302/230 found in the 68 Cougar. The rules say to use the heaviest gas engine body as the shipping weight, which is the 68 convertible 428/335 . That's where the 3369 comes from. The engine is rated at 220 with 10 added for the AFR 1399 heads.

As I understand it, GT is like building a car that never came off the production line even though it has the right brand parts in it. So a weight is assigned to the body and the class is determined by the engine factor. It could have been the actual weight of the body used (68 Mustang coupe) or an average 68 Mustang weight, but someone decided on using the heaviest one available. I guess.

Dale

Dwight Southerland · 12-02-2014, 10:18 PM

The heaviest coupe weight is 3241, which is what you would use for calculation. You would not use the convertible shipping weight for a coupe body.

FireSale · 12-03-2014, 02:12 AM

Quote:

Originally Posted by Dwight Southerland

The heaviest coupe weight is 3241, which is what you would use for calculation. You would not use the convertible shipping weight for a coupe body.

Thanks. That's a further clarification. The rule just says heaviest vehicle and dosen't differentiate between heaviest 68 Mustang (the convertible) or heaviest vehicle you are using (68 coupe).

Thanks again.

Dale

aross6 · 12-03-2014, 10:32 PM

Quote:

Originally Posted by FireSale

Thanks. That's a further clarification. The rule just says heaviest vehicle and dosen't differentiate between heaviest 68 Mustang (the convertible) or heaviest vehicle you are using (68 coupe).

Thanks again.

Dale

Actually the rule doesn't say the heaviest vehicle, but rather "Shipping weight will be determined by using the
power to weight factor of the vehicle with the heaviest gasoline engine and appropriate transmission." The vehicle with the heaviest engine is usually the heaviest vehicle, but not always... just something to keep in mind.

Dwight Southerland · 12-04-2014, 02:23 PM

I think the wording is meant to imply the vehicle in question. In this current example the vehicle in question is a 68 Mustang coupe. Don't try to make their wording more technically legalistic than it is. The opening description of the rulebook section states "Cars will be classified using the shipping weight of the body divided by thehorsepower or performance rating of the engine used." The body in that statement is the body you have, not anything else. The intent is to use the heaviest shipping weight of the particular model-body you have. So, for example, you can't use the shipping weight of a 4- or 6-cylinder Camaro when calculating the class when the V8 models were heavier.

JP Schuster · 12-04-2014, 03:07 PM

Hi Guys,

Sorry to hijack this thread but I am in the process of building a GT car of my own and I am new to this class stuff... But anyways, I just wanted to have some sort of clarification or maybe confirmation on what I calculated for shipping weight/classes I can run personally.

Here's the combo:

LS1 Body style Camaro COUPE (1998-2002)
Automatic
327/275HP 1968 Camaro motor (OEM Heads) - 299HP factor (I believe)

Using your tips from the templates,

If I read correctly,

The heaviest coupe is 3370 in 1998. the factor is 12.08 and the HP is 285.

So 12.08 X 285 = 3443 (Shipping Weight) divided by my 299 HP is 11.514 which is my base for classes? So I can run the car at 3443 + or - 250. More specifically, my weight would be the minimum ratio for the class X 299HP + 170?

I would hopefully just like to confirm this and make sure that I am using the right shipping weights and base ratios (3370 lbs and 12.08)

Thanks in advance for the help!

JP

FireSale · 12-04-2014, 03:28 PM

Quote:

Originally Posted by JP Schuster

Hi Guys,

Sorry to hijack this thread but I am in the process of building a GT car of my own and I am new to this class stuff... But anyways, I just wanted to have some sort of clarification or maybe confirmation on what I calculated for shipping weight/classes I can run personally.

Here's the combo:

LS1 Body style Camaro COUPE (1998-2002)
Automatic
327/275HP 1968 Camaro motor (OEM Heads) - 299HP factor (I believe)

Using your tips from the templates,

If I read correctly,

The heaviest coupe is 3370 in 1998. the factor is 12.08 and the HP is 285.

So 12.08 X 285 = 3443 (Shipping Weight) divided by my 299 HP is 11.514 which is my base for classes? So I can run the car at 3443 + or - 250. More specifically, my weight would be the minimum ratio for the class X 299HP + 170?

I would hopefully just like to confirm this and make sure that I am using the right shipping weights and base ratios (3370 lbs and 12.08)

Thanks in advance for the help!

JP

Given the info from this thread, the original template I posted isn't accurate in regards to weight. Reread the entire thread. especially post 16 from Dwight.

Find your car on the Stock Classification Guide and take the shipping weight
from that car's heaviest gas engine with the trans you are going to run.

If your body is a 98 Camaro coupe auto, use the shipping weight of the one with the biggest gas engine offered. I don't have data here, but if they sold it with a six and a 427, use the weight of the 427.

Once you have your shipping weight, remember what they keep telling me. It never changes, just the factors with different engine combos.

Take your shipping weight to the engine listing at the top of the classification guide and divide the weight by various HP ratings to get class factors. Be sure to use the GT factors in regards to HP ratings. Find the posts here about HP weight factors for replacement heads, too.

EDIT: LS1 shows up in the Guide starting in 99. You need to pick a year to get the body weight right. It looks like that would be a Z28 coupe with the LS1 engine? I'm a Ford dude...

99 Camaro Z28 Coupe 427 auto weight 3291

327/275HP 1968 Camaro motor (OEM Heads) - 299HP factor (I believe) Yes

3291 / 299 = 11

GT/GA

Dale

JP Schuster · 12-04-2014, 04:07 PM

Thanks Dale!

Dwight Southerland · 12-04-2014, 04:13 PM

Go to www.classracerinfo.com Register as a user and use the tools there. Much easier, faster.

12-02-2014, 08:30 PM	#11
Ryck Campbell Junior Member Join Date: Dec 2001 Location: Rome, NY Posts: 56 Likes: 176 Liked 46 Times in 10 Posts	Re: GT Classification Worksheet Fire Sale, If you car is a convertible then 3369 is correct. If not then 3267 is the shipping weight to use. With the engine rated at 335 the your non convertible would run C @3185 or D @ 3350 or E @ 3520. A convertible would run C @ 3285, D @ 3350, E @ 3520 or F @ 3685. These weight are class minimums. The convertible can't get to the top of C and would have to run 100 heavy for the class. __________________ Ryck Campbell NHRA Technical Specialist

12-02-2014, 10:18 PM	#13
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 1,999 Likes: 64 Liked 772 Times in 192 Posts	Re: GT Classification Worksheet The heaviest coupe weight is 3241, which is what you would use for calculation. You would not use the convertible shipping weight for a coupe body.

12-04-2014, 02:23 PM	#16
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 1,999 Likes: 64 Liked 772 Times in 192 Posts	Re: GT Classification Worksheet I think the wording is meant to imply the vehicle in question. In this current example the vehicle in question is a 68 Mustang coupe. Don't try to make their wording more technically legalistic than it is. The opening description of the rulebook section states "Cars will be classified using the shipping weight of the body divided by thehorsepower or performance rating of the engine used." The body in that statement is the body you have, not anything else. The intent is to use the heaviest shipping weight of the particular model-body you have. So, for example, you can't use the shipping weight of a 4- or 6-cylinder Camaro when calculating the class when the V8 models were heavier.

12-04-2014, 03:07 PM	#17
JP Schuster Junior Member Join Date: Mar 2012 Posts: 54 Likes: 0 Liked 0 Times in 0 Posts	Re: GT Classification Worksheet Hi Guys, Sorry to hijack this thread but I am in the process of building a GT car of my own and I am new to this class stuff... But anyways, I just wanted to have some sort of clarification or maybe confirmation on what I calculated for shipping weight/classes I can run personally. Here's the combo: LS1 Body style Camaro COUPE (1998-2002) Automatic 327/275HP 1968 Camaro motor (OEM Heads) - 299HP factor (I believe) Using your tips from the templates, If I read correctly, The heaviest coupe is 3370 in 1998. the factor is 12.08 and the HP is 285. So 12.08 X 285 = 3443 (Shipping Weight) divided by my 299 HP is 11.514 which is my base for classes? So I can run the car at 3443 + or - 250. More specifically, my weight would be the minimum ratio for the class X 299HP + 170? I would hopefully just like to confirm this and make sure that I am using the right shipping weights and base ratios (3370 lbs and 12.08) Thanks in advance for the help! JP

12-04-2014, 04:07 PM	#19
JP Schuster Junior Member Join Date: Mar 2012 Posts: 54 Likes: 0 Liked 0 Times in 0 Posts	Re: GT Classification Worksheet Thanks Dale!

12-04-2014, 04:13 PM	#20
Dwight Southerland VIP Member Join Date: Dec 2001 Location: Arkansas - In the middle of everything. Posts: 1,999 Likes: 64 Liked 772 Times in 192 Posts	Re: GT Classification Worksheet Go to www.classracerinfo.com Register as a user and use the tools there. Much easier, faster.