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curt
02-15-2006, 10:10 PM
I adjusted the carberator on my 4 barrel 289. I turned the 'adjustments' counter clock wise and it ran faster and faster, 200 rpm increase. Now I have one deep throat/hot rod sound when I put the pedal to the metal. Does this seem OK?

DEEPNHOCK
02-15-2006, 10:53 PM
The best way to set the idle screws on a carb is to adjust the screws to get the highest rpm possible with the screws screwed in as far as possible. Either that or use a vacuum gauge and set the screws for the highest vacuum reading possible. Or... set the screws to give you the best fuel air ratio possible using a sniffer (who has one of these...and uses it????)
Jeff[8D]


quote:Originally posted by curt

I adjusted the carberator on my 4 barrel 289. I turned the 'adjustments' counter clock wise and it ran faster and faster, 200 rpm increase. Now I have one deep throat/hot rod sound when I put the pedal to the metal. Does this seem OK?

N8N
02-16-2006, 09:22 AM
you mean the "giant sucking sound?" That's a *good* sound <G>

anyway, as far as setting the idle goes, I thought what you did was back the screws out until the idle starts to drop (rich) then screw them back in until it just starts to drop again (lean) and then leave them there, this way you don't "load up" when stuck in traffic.

Of course I suck at working on carbs; up until I started messing with Studes most of my "project" cars were VWs with mechanical FI.

nate

--
55 Commander Starlight
62 Daytona hardtop
http://home.comcast.net/~njnagel

Mike Van Veghten
02-16-2006, 02:44 PM
If I may add a thing or two -

The engine must be hot (full running temp.), and I've had very good luck with doing the adjustment with the car in gear (e-brake on and tires blocked)...IF it's an automatic. If you're carefull, there seems to be a noticable difference with a load on the engine.

The same thing with the motorcycles. The manuals say to syncronize the carbuetors at idle. Well...I don't really care how good they are at idle...I care at an engine speed where the clutch is just fully engaged, the throttle is comming open and the engine is fully loaded. THAT'S where I want the engine running it's best.

Ron Dame
02-17-2006, 07:23 PM
How many turns did you make? They should be *roughly* 2 full turns on most carbs...over 3 means you have a vacuum leak somewhere.



quote:Originally posted by curt

I adjusted the carberator on my 4 barrel 289. I turned the 'adjustments' counter clock wise and it ran faster and faster, 200 rpm increase. Now I have one deep throat/hot rod sound when I put the pedal to the metal. Does this seem OK?


Ron Dame
'63 Champ

DEEPNHOCK
02-17-2006, 07:39 PM
I concur...
I used to tune my I/O boat with my wife.
She'd drive and hammer the throttle from a standstill and I would adjust the timing where it would just rattle a tad...
Damn, I wish I could do that with a Stude (without risking life and limb[B)])
Jeff[8D]




quote:Originally posted by Mike Van Veghten

If I may add a thing or two -

The engine must be hot (full running temp.), and I've had very good luck with doing the adjustment with the car in gear (e-brake on and tires blocked)...IF it's an automatic. If you're carefull, there seems to be a noticable difference with a load on the engine.

The same thing with the motorcycles. The manuals say to syncronize the carbuetors at idle. Well...I don't really care how good they are at idle...I care at an engine speed where the clutch is just fully engaged, the throttle is comming open and the engine is fully loaded. THAT'S where I want the engine running it's best.

N8N
02-17-2006, 07:51 PM
Jeff,

just cut a hole in the firewall, you can have your helper sit on the floor and reach under the dash to adjust the timing while you drive. This is ASSuming a Stude or McKinnon engine, F*rd or B/RB MoPar swaps are a little more challenging and may involve mechanic's wire or clothesline at some point.

hope this helps,

nate

--
55 Commander Starlight
62 Daytona hardtop
http://home.comcast.net/~njnagel

DEEPNHOCK
02-17-2006, 09:05 PM
You may laugh, but this has been done before....
Jeff[8D]


quote:Originally posted by N8N

Jeff,
just cut a hole in the firewall, you can have your helper sit on the floor and reach under the dash to adjust the timing while you drive. This is ASSuming a Stude or McKinnon engine, F*rd or B/RB MoPar swaps are a little more challenging and may involve mechanic's wire or clothesline at some point.

hope this helps,

nate

--
55 Commander Starlight
62 Daytona hardtop
http://home.comcast.net/~njnagel

clarkwd
02-18-2006, 06:07 PM
When we were in High School my brother and a crazy friend changed an engine in the friends garage a couple miles away. Between houses was a notorious corner. My mother saw them drive in with Craven riding on the front fender of a 55 Ford with no hood. When they came into the house he remarked that my brother, who was driving, had come through Kings corners at more than 70mph with him on the fender. What were you doing on the fender Craven? "Oh, I was working the gas!"
Bill