HFC + Exhaust + Intake = 12's?

Phimosis

it's not going to break into the 12's where I live. :-(
I have been out of town, but our last "test and tune" was last Friday. If I had went there after work, the DA would have been 2860 (Famoso raceway, May 29). A 12.70 sec @ 107 mph car at a DA of 2860 corrects to 13.25 sec @ 105 mph.

The seat of the pants dyno tells me the same thing. My vette ran a 12.8, but is way faster than my 370.

To be honest, my car was "bogging" from 5,000-7,000 rpm. I thought it might be from detonation (and subsequent timing retard) because the weather was almost 100 degrees and my timing is advanced over stock. So, on an empty tank I put 5 gallons of 100 octane unleaded in it and dynoed it. The breeze was running the wrong way through the shop, helping to heat soak and keep intake air temps sky high. The ambient temp was already 98 degrees. The runs were on a dynojet. The best run? 290hp. :-( with intake, exhaust, cats, headers, remapped ecu and race gas... Only 290hp. There's just no way I'm going to get into the 12's on the track where I live.

ianthegreat

Famoso is a great track. One of the fastest in the country some days.

Phimosis

When your talking NHRA, the limiting factor is traction, not power. If you have 105F ambient temps with 200F Aspalt, you get incredible traction. If you're only making 7,200 hp in that condition vs. 8,000 hp on a track with 65F asphalt, you'll pull a very low ET even though your trap speed is low. On a 332 hp car in those conditions, making 298 hp will kill your ET and trap because traction was never a (big) problem. (I used 90% of max power in both calculations).

ZforMe

Where are you getting the DA corrections? Can you check my 13.212?

Thanks,

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13.369 @ 102.73 Bone Stock. BERK HFC's installed 5/14/09 @ 1490miles, 13.212 @ 106.15. Cobb Post MAF Hoses installed 3/20/10 @ 5,043miles, future: FI exhaust with 18" res and s/s cans.

wstar

I used this: DA Calculator - Density Altitude Calculator - DragTimes.com

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ianthegreat

The top 335i's on dragtimes have all set the records at Famoso. Someday I'm going to make it out there, maybe fly out for a weekend. But I understand what you're saying.

Phimosis

Well, I finally went out and ran my Z. Worse than I expected at Famoso.

8pm at night, 94 degree track temperature. Density altitude = 3186. Something bad happened with track prep. Guys that I know that run 11.5's were turning 12.5's because no one on street tires were getting traction.

On 91 octane I turned 14.0 @ 101.8 with a 2.3s 60 foot which was all spinning with 3500 rpm launch. Used 8,000 rpm shift point. With traction control on I ran 14.4s. Looks like I'll have to wait until fall to see some decent numbers at this track.

-Phim

KingDavid

Yikes, that's slower than stock...Time for tires?

theDreamer

Run sounds fine compared to what others were running, sounds like bad track and high altitude.

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t-ray

A 2.3 second sixty isn't very good, but even with a 2.1 second sixty he would have seen about a 13.7 second run with that trap speed. It was definitely the altitude/air that hurt him the most.