Ol' Fart's Firebird Fantasy

[Danny Ashley]

Go to the top of this page and click on NHRA Competition. Then click Stock car classification on the left of the page. Then find the make and year and open it up.

[oldskool]

Originally Posted by Danny Ashley

Go to the top of this page and click on NHRA Competition. Then click Stock car classification on the left of the page. Then find the make and year and open it up.

OK, THANKS !

It takes longer to get there, but it does show the 260hp factor for non-Birds, AND shows the correct calculations for them. So, I need to depend on this NHRA site for all final calculations--Got it ! Thanks again !

[oldskool]

OK guys, I still need an answer to the weight change questions. When we raced Stock, you were stuck with whatever your factory shipping weight was. That was your min weight. So please tell me EXACTLY how the weight and class changes work. THANKS !

(1) Can you add weight to make the next lower class ?

(2) Can you remove weight to meet the minimum weight for your natural class ?

(3) Can you remove enuff weight to meet the minimum weight for the next higher class ?

(4) Is there a max amount of weight you can remove below your shipping weight ?

(5) Explain EXACTLY how the driver weight figures in again. Maybe I'll get it all, this time.

[HandOverFist]

WEIGHT
All cars will be permitted to run on the class minimum weight, but
may be no heavier than the minimum for the next heavier class.
Car can move up (lighter) one class or down (heavier) one class. If
weight is added, must be properly attached; see BALLAST. Class
and classification weight are determined without driver weight.
Once classification weight is calculated, 170 pounds is added for
driver to arrive at total weight. All cars are weighed with driver.

[oldskool]

Originally Posted by HandOverFist

WEIGHT
All cars will be permitted to run on the class minimum weight, but
may be no heavier than the minimum for the next heavier class.
Car can move up (lighter) one class or down (heavier) one class. If
weight is added, must be properly attached; see BALLAST. Class
and classification weight are determined without driver weight.
Once classification weight is calculated, 170 pounds is added for
driver to arrive at total weight. All cars are weighed with driver.

OK, THANKS ! That clears it all up, except for one thing. I just wanna be sure, so I'll ask again. Is there no limit to the amount of weight you can remove in order to meet the min for the next higher class ?

[HandOverFist]

Originally Posted by oldskool

OK, THANKS ! That clears it all up, except for one thing. I just wanna be sure, so I'll ask again. Is there no limit to the amount of weight you can remove in order to meet the min for the next higher class ?

No restrictions other than you will reach a point depending on the platform where there is simply no viable way to remove any further weight. Our '67 Camaro for instance...we had to add 20 pounds to meet minimum weight for E/SA which means I would have to find around 120 pounds to remove in order to arrive at D/SA minimum. Our car still has the factory seats which are a tad on the heavy side...aftermarket seats would help to a point, but it would be a struggle to find more in this particular car.

[oldskool]

Originally Posted by HandOverFist

No restrictions other than you will reach a point depending on the platform where there is simply no viable way to remove any further weight...

OK, Thanks a lot ! I really appreciate all the info ! If I don't understand the weight deal now, it's my own fault and I probably don't need to think about a class car anymore.

[impstocker]

OK I want to throw my .02 in. Earlier in the thread you were considering a "big Body" like 1976 Pontiac, I guess this would be a GM B Body car (1971-1976) I have never been underneath one but I did some research looking for diagrams or photos of rear suspension but came up empty. I did come across aftermarket parts though for these cars which include Control arms which tells me they are coil spring cars not much different than the 65-70 B Body gm car like my Impala.

If I am wrong here then skip the rest.

These are different from A Body cars which some guys have been showing you for rear suspension upgrades. The first difference is the coil springs perch between the lower control arm and frame, not on axle tube like A Body rears. The upper control ares are a straight forward shot, not angled like A Body cars. Some early B Bodies like my 65 came as a "3 link" rear suspension, 2 lowers only 1 upper bar. Hi-Performance did have 4 links like I have in the 65 Impala stocker I am building. No-Hop bars are not available for these cars .I have Southside Machine lower control arm traction bar which is basically a Square tube solid bushing bar with a adjustment that lowers the attachment point on the axle effectively changing the instant center of the car which aids in planting tires. The same effect is done with the "No-Hop" bars on the A Body cars. With adjustable Upper control arms, no air bags thats all I needed to do. Not really complicated. The only heads-up is where the upper bars attach to the crossmember on frame needs to be strengthen. I would leave at 6300+ RPM with a stick at 4095 lbs. Check out my Build in this forum,
"BBC Impala update" or something like that.

I would crawl under the cars to take pics but lots of snow , blizzard outside now!

Will Lamprecht I/SA Implala in progress.

[impstocker]

OK, this might be "blasphemy" even though the pics of the Wood's "Ton's O Fun" station wagon looks as cool as crap, I would say the suspension is not set up right and wasted motion produces wasted horsepower = lower ET's ? I liked the fact my Impala launched straight and level. Aren't we looking for that?

Will Lamprecht I/SA 65 Impala in progress

[oldskool]

Originally Posted by impstocker

OK, this might be "blasphemy" even though the pics of the Wood's "Ton's O Fun" station wagon looks as cool as crap, I would say the suspension is not set up right and wasted motion produces wasted horsepower = lower ET's ? I liked the fact my Impala launched straight and level. Aren't we looking for that?

Will Lamprecht I/SA 65 Impala in progress

Yeah, that's exactly what I thought when I first saw that pic. A couple of years back there was a Chevelle that ran at our local track that did the exact same thing.

Back when I ran my '69 bracket GTO, I moved the batt to the right rear of the trunk. But both tires came off the ground just quick enuff to cause a redlight, when leaving at the 1st hint of light from the bottom yellow.

So, I moved the batt as far as I could to the left front of the car, on the frame rail. This didn't keep the left front on the track, but it did keep the right front rolling on the track instead of in the air. And, since one tire is all it takes to block the beam of light, the redlight problem was fixed.

All I had was air bags and stiffened rubber bushings. And I put more air in the right side. That set up was all I needed for the racing I was doing. But exactly what is the procedure for setting up the suspension on an A-body, to prevent this body twist, or whatever it's called, and make it leave level and straight ?

I assume there are lots of sites that have this info online. I haven't done a search. But I'd like to hear from some of you guys about what you did to make your A-body suspension work. I've already read that some just used air shocks, or air bags and stiff bushings. Some used adjustable upper arms, or no-hop bars. So apparently there is more than one way to do it. So I'd like to hear more.