I'm not sure I could imagine a worse day for racing with it as humid and hot as it was, but I still had a good time, as anytime I have an excuse to go fast in the GTA.

Anyways. Question about times, they're kinda screwy.

-Cordova Raceway three weeks ago. 8:27pm, mid 70's, very nice weather for racing. Best run: 13.369@100.43

Carb was changed from Edelbrock 600 to Edelbrock 750...

-US41 today. 1:14pm in crappy racing conditions. Best run: 13.493@104.40

I'm pysched about picking up 4mph's with the new carb, but the fact that I'm running more than a tenth over my best ET kinda worries me. Can I blame the weather?

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1990 GTA
-355 carb'd, nicely reworked '64 vette heads, 2500 stall, 4.10's, other small things.
-Alston SFC's, Eibach Pro-kit, Koni's all around
-100+ nitrous shot
-Cruising in style with leather and nice stereo.

 

No. The MPH increase is a good result of increased HP. The weather will change the engines HP output but ET depends on traction. The effect weather has on traction is minimal. It can heat up or cool down the track which will change traction conditions. Other weather factors are wind but temperature, barometric pressure and humidity are the key factors against HP.

It's possible that the increased HP is causing excessive tire spin off the line. How much different are the 60 foot times. That will be the best indication of tire spin.

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Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z SuperPro ET Bracket Race Car
461 naturally aspirated Big Block

Best ET on a time slip: 11.242 altitude corrected to 10.89
Best MPH on a time slip: 121.52 altitude corrected to 125.89
Altitude corrected rear wheel HP: 497.9
Best 60 foot: 1.546

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

hmmm...

well the 13.36 run had a 1.93 60' and the 13.49 run had a 1.95 60' ...this just got more confusing

 

Not really. The 60 foot times are consistant with the ET. Since your MPH is up I'd say you probably have some tire spin.

With the increase in MPH (ie. HP) your top end is stronger. Are you getting more rpm out of every shift point? Are you crossing the finish line at red line?

 

I was shifting at 5800 with the 13.36 run and I was shifting at 6000 with the 13.49 run.

The cam range is 2500-5800, so I might be shifting too late, but I'm crossing the 1/4 right around 5500 so it's real close the way I have it now.

Are you saying that even though the 60's are close, that's only because I have the HP now to get a 1.95 60' even with wheelspin?

 

Does it matter that the first run was 8:30 at night and the second one was 1 in the afternoon?

 

No it doesn't matter. As stephen said your MPH is up meaning you have more HP than you had before. You are just not using it somehow.

 

RPM = HP, by spinning the engine faster, you were picking up MPH, but probably loosing a little torque.

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Black 89 IROC...355, Solid Crower Cam, TFS heads.
12.0 @ 120.3mph with a 1.9 60ft...all motor

 

all motor 12flats at120 mph?thats incredibule!!!!normally 120 would put you in the low 11's.what;s in your combo?

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87 IROC WITH 409(.040 OVER400) MINIRAM,NOS(125HP)TRICK FLOW PORTED HEADS,C.C.CAM,FLOWTEK HEADERS,CUSTOM PROM,MODIFIED 700R TRANS,2400 B&M CONVERTER,3.73POSI REAREND.
LOOKING FOR THE 11 SEC. ZONE.current ets.12.39@114 mph

 

That is a wierd et/mph. I used to run 11.8's at 117 mph with bad gearing.

To get that combination I'd have to say there's lots of HP and maybe 2.77 gears. That would explain the 1.9 60' times.