Desktop Dyno?

Hey, can someone here crunch some #'s for me on DD? I have my first show coming up this weekend and I'll feel kinda dumb saying, "I really have no idea."

- 1986 5.0L H.O. engine (stock '86 flat-top pistons)
- E6 heads -- thermactor bumps removed, port & polish, skirts ground down
- Custom cam: .491/.471, .219/.209 @ .050, 112 deg sep
- Weiand 289 tunnel ram intake (P/N 1988)
- sync'd dual Holley 390 cfm vac secondary carbs (P/N 8007)
- Pertronix ignition
- MSD Blaster II coil
- Full-length 1 5/8" headers, Turbo mufflers, 2.5" pipes, no cats

And if you could run it with GT-40 heads, too; I'd be interested in the difference -- I have an opportunity to pick up a set on the cheap.

I'm thinking about 250-275 hp.

Thanks in advance,

- Joey

sorry its tuesday i just seen youre post. but after i get home from work today ill dtd it for ya. i have a comp cams dtd wich is within 5% accurate

Thanks, man. Very cool of you.

I have a 86 Ho f.i..They were rated about 225 stock,with the bunk heads:LOL: .You should be close to 300,with the tunnel ram and those heads.Those cars are light,soo you should be able to keep up with the new mustangs!!:D Just dont follow the new ones thru the corners:LOL:

Can't help you with the numbers but was just wondering how those dual 390's work on your motor? Thinking of doing the same.

Quote:

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Originally Posted by shawnlee28

I have a 86 Ho f.i..They were rated about 225 stock,with the bunk heads:LOL: .You should be close to 300,with the tunnel ram and those heads.Those cars are light,soo you should be able to keep up with the new mustangs!!:D Just dont follow the new ones thru the corners:LOL:

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There's a considerable sphincter factor when those secondaries open up. It morphs into an entire other motor past 4K.

Quote:

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Originally Posted by chevy 37

Can't help you with the numbers but was just wondering how those dual 390's work on your motor? Thinking of doing the same.

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The 390's rock. Please check out my cardomain site, particularly page 2, where I go into length about the tunnel-ram part of the build.

I run them with stock jetting, and literally bolted them on and laid a 50' patch down my father-in-law's driveway ten minutes later. The roller-cam engine, with its quick throttle response, seems to be a good fit for the tunnel-ram -- this is an older 289 "street" tunnel ram -- and the 390's appear to be an ideal size for a small-block. It runs a little rich and idles a little quick to get a good scary lope out of the cam, but it runs nice.

EDIT: They are Holleys, though. If I could do it again, I'd buy Edelbrock 1403's and save myself a couple hundred dollars in Excedrin.

I've heard the 390's are hard to dial in. Also need to have power check valves/ I have two 600 polished cfm edelbrock carbs sitting on a offy intake but way to much carbs for my engine. I think even the 500 edelbrock would be to much although I've run a couple 3 duece set up which push me back into my seat when I open them all up. Love the looks of the dual 4 barrel's and the sound is to much:D

Hey, Denny. Long time. You know what a PITA these Holleys have been from time to time. . .

Chevy37, the power valve reliefs are a cinch to put in. My problem with the Holleys wasn't so much dialing them in, as it was keeping them running; mostly rookie mistakes, though. Not using Vaseline on the injector needles, for instance. And before that, I had a sticking vacuum advance that kept annihilating my power valves until I tracked the problem down.

Dual quads are high on my "Hot Rod Glory" list, too. Wow factor, sweet sound, and tons of power. I like mine. . . when they run. . ..

Glad to help can you give me the valve size, compression ratio and the intake and exaust open and close points on the cam. if i use youre lift and duration the computer will automatically determine them and they may be off a hair

Here is what I get with appromating some of the inputs. I got the compression ratio from:

http://www.mustanggt.org/86gt.htm

http://www.virtualengine2000.com

was 2 if you still want me to run it i need the specs from the cam card intake and exaust advertised duration,intake center line and valve timing

Glenn, I don't have that info handy. I'll PM you with it in a few days. Thanks!