RACING What did I miss? (cry for help)

Clipclop80

Not-quite-so-new-guy
Apr 9, 2021
21
3
New to forum, guys... but I need a hand.
first I'll describe my 1980 Lemans build.
406 SBC dyno'd at 523 HP 527 TQ had it built for me, didn't do it myself.
cam; hyd roller, 232/240 574/558 110LS
10.5:1 CR
intake air gap port matched
all poly mounts, engine, trans,& suspension.
700R4 with servo upgrades etc.
12 bolt 3:73
full interior & stereo (extra weight)
750 quick fuel, 1-5/8" headers into 2.5" exhaust with mufflers (fairly quiet)
275 60-15 nitro 555 rear drag radial 235 fronts
stock front springs with sway bar
stock rear springs with UMI 12 bolt conversion top & bottom links
air shocks in rear.

Question:
this setup has gone a best 12.56 @ 108 @ 2200 ft on 93 octane.
where am I missing out? should this setup not go sub 12 all day long?

any help is appreciated.
IMG_4335[1].jpg
 
Last edited:

-dw-

Apprentice
Mar 15, 2021
80
33
Central MN
ET matches MPH. Definitely doesn't match close to dyno numbers. Missing some hp there. I would suggest making sure your fuel system is up to the task. Get extension for the fuel gauge to watch it in the car. Thrash it and watch if maintains fuel pressure. When my olds went into the 12s I had a devil of a time feeding it with stock type fuel system.
 
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64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
3,429
113
Upstate NY
You're missing the 200 shot of Nitrous Express.

What's your best 60'?
 
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Clipclop80

Not-quite-so-new-guy
Thread starter
Apr 9, 2021
21
3
ET matches MPH. Definitely doesn't match close to dyno numbers. Missing some hp there. I would suggest making sure your fuel system is up to the task. Get extension for the fuel gauge to watch it in the car. Thrash it and watch if maintains fuel pressure. When my olds went into the 12s I had a devil of a time feeding it with stock type fuel system.
that's somewhere I haven't looked...checked fuel supply and filter assy. wondering if there was a restriction. The Edelbrock 1721 pump is rated at 6 PSI but maybe I have to check the pressure while beating on it. Thank you.
 
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1320John$$$

G-Body Guru
Sep 18, 2019
939
93
Pennsylvania
Try getting your fuel line off the header No need to boil the fuel before it goes into the carburetor
 
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Clipclop80

Not-quite-so-new-guy
Thread starter
Apr 9, 2021
21
3
Try getting your fuel line off the header No need to boil the fuel before it goes into the carburetor
It looks like its close, but has almost 3" clearance. all input is appreciated! thanks! 406 dyno sheet.jpeg
 
Last edited:

Clipclop80

Not-quite-so-new-guy
Thread starter
Apr 9, 2021
21
3
Prob not. My car will 60ft low 1.6 with 700, 3.42 and 26in tires.
Interesting. I'm missing something pretty important then. do you start in low and manual shift?
what about converter? I foot brake at only 2100. I could send a video showing what it sounds like off the line if you're interested in that?
 

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