How about those ford cj's at vegas

[Steve Hagberg]

EVAN; Your comments on effect of altitude on a supercharged engines performance are correct, except that you forgot to mention the offsetting effect that helps to keep these cars faster at tracks such as Las Vegas. Since a blower takes HP to compress the ambient air, less dense air will lower the blower output pressure, but will also lower the Hp needed to compress it. The power needed to run a blower is significant, so the 'gain' from reduction in load is also significant.
Steve

[Evan Smith]

Steve,

Can I assume that you've measured the differences at different boost levels in order to report these findings? In theory you are right, but we are talking about small changes in boost level from good air to bad air. Probably 3-4 psi on the CJs from sea level to Vegas. The cost to drive the blower for that extra 3-4 psi is very, very small.

I've tested over 100 blower cars with all types of blowers over the years and while I've not measured crank hp, save for one time on a 1,200 hp engine, I can tell you the loss in power from adding a few pounds of boost is not a lot. In that case it took upwards of 250 hp to run the blower. I would guess a change in boost, even at that level, would have very little effect on overall power loss/gain. Again, in theory you are right, but in practice the gain/loss is not what you think.

Most blower engines are designed to run with boost pressure so even if you removed the blower it wouldn't give you a fair result on power because the engine would likely be inefficient with no boost.

Evan

[countrypuppy4865]

I was just wondering if anyone else noted the increments on Don Fezell's CJ in Richmond. To compare go to http://www.nhra.com/livetiming/livetiming.aspx and click on Race Archives. Find Virginia NHRA Nationals and click results. Compare Friday's Q1 increments to Sunday's R2 increments. They are pretty amazing!

[Alan Roehrich]

Originally Posted by Scott Loge

Keep in mind when the camaro and firebirds first came out were they not F,G and H cars, now b,c and d. It may take awhile but it is still good for our class. It may hurt now but an injection of some sort is better than sitting idle.

New blood stings when first injected but sooths other faults

And the Mustangs started in A and AA, so, other than not being able to run A after about Tuesday, where do they go from here?

Since it had already happened before, there was no excuse for it to happen again. Constant repetition of "it happened X years ago with Y cars" doesn't make it right for it to happen again with a different car or cars. What it does is either make NHRA look like fools for letting it happen again, or make us look like fools for letting NHRA do it to us again.

I don't see any "other faults" that bogus race cars with under factored engines capable of running 2 seconds under their indexes are "soothing". They sure as Hell won't inspire NHRA to do anything with the AHFS, and in fact, it'll probably be just the opposite. They won't inspire anyone to build anything to race, either, except a few who have plenty of money and can afford to either buy these new "factory race cars" or build copies.

Honestly, I can't see where this is so "good" for Stock or Super Stock. Did the entire class get anything out of it? No. We didn't get sudden national exposure in print, nor an increase in television time, either. There hasn't been any real increase in the purse or contingencies (for the most part, entry fees went up, and as a general rule, contingency payouts went down, while the purse remained the same as it has for years). We aren't treated any better by NHRA, either. I keep looking for all of this improvement these new cars are supposed to be bringing. It ain't happening.

[Superfan1]

Originally Posted by RULER

When they get there NHRA gift of 14HP on monday they will have to carry 112lbs more so they will only be about 3 to 4 tenths quicker than the best none C.J. car out there. These cars shouldn't be in stock they should be in super stock, you don't see any 68 darts or barracudas with race hemis running stock and thats because they weren't street legal cars just like these new factory race cars are, Wake-Up NHRA!!

They won't have to carry 112 lbs. more because they will only be legal for AA/S and AA/SA with their new factor of 7.38. They will only have to add weight to get to the 7.50 AA/S and AA/SA factor. In A/S and A/SA their class minimum weight was 3400lbs (8 x 425); now their class minimum will be 3293lbs (7.5 x 439). As I see it, the main effect will be that they will have to run off of the much tougher 10.90 AA/S and AA/SA index instead of the 11.25 A/S or the 11.30 A/SA indexes.
Bill Seabrooks - superfan1
Bridgeport, Ct.

[Alan Roehrich]

Originally Posted by Superfan1

They won't have to carry 112 lbs. more because they will only be legal for AA/S and AA/SA with their new factor of 7.38. They will only have to add weight to get to the 7.50 AA/S and AA/SA factor. In A/S and A/SA their class minimum weight was 3400lbs (8 x 425); now their class minimum will be 3293lbs (7.5 x 439). As I see it, the main effect will be that they will have to run off of the much tougher 10.90 AA/S and AA/SA index instead of the 11.25 A/S or the 11.30 A/SA indexes.
Bill Seabrooks - superfan1
Bridgeport, Ct.

That they will still be able to run at least 1.5 to 2.0 seconds under.

[ROY]

The guys complaining about horsepower numbers must be GM guys.Take a 375hp,396,same specs as a 425hp,396,soooooo.Think of the many hp factors for basically the same 350 chevy engine.NHRA has always facrored according to who makes the most noise and who is their biggest sponsor at that time! JMO,got out of "stock" in the 70's when it was getting stupid! ROY.

[Alan Roehrich]

Originally Posted by ROY

The guys complaining about horsepower numbers must be GM guys.Take a 375hp,396,same specs as a 425hp,396,soooooo.Think of the many hp factors for basically the same 350 chevy engine.NHRA has always facrored according to who makes the most noise and who is their biggest sponsor at that time! JMO,got out of "stock" in the 70's when it was getting stupid! ROY.

The 396/375 and the 396/425 were virtually identical, and remained the same for the 396/375 for 4 years after. The 425 rating was a marketing ploy.

If you flow the heads and intakes for those "basically the same" 350 engines, you'll find they are actually a bit different.

[Dick Butler]

Guys many of you are missing the Point of the Mustangs. It got a factory to be interested in Drag racing again. NHRA wins. It got several more entries to events by guys seeing the bogus HP and jumping into them. NHRA wins. Everyone else keeps bringing their cars and racing NHRA wins. Many people talk about the injustice but are powerless to change it. NHRA at least breaks even....This is not about Fairness, it is not about racing, it is not about good factoring or intelligent thought related to the cars.... it is all about NHRA making money... Correctly done or poorly done... they continue to use the same thinking to do it..Our choices are continue to go and pay them entry, continue to complain of the unfairness and just race or..... Sad it kills the hobby many of us lived for...

[Floyd Staggs]

The last of the cj's is gone. Ran dead on with a 0 and still lost.
I guess all that extra horsepower didn't help.