What Are You Doing To/With Your Car Today?

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Spent yet another afternoon trying to tune my new 950 carb for a lean cruise. To make a long story short, it can't be done without significant compromises in AFR, since my cam has 8" idle vacuum but 15" cruise vacuum, and it's still on the transfer slots even at 60 mph/3000 rpm. I'm going to try playing with idle feed restrictors and see if I can live with the lean off-idle flat spot that will invariably result, but seriously thinking of putting the old 800 back on.
 
DrCharles said:
Spent yet another afternoon trying to tune my new 950 carb for a lean cruise. To make a long story short, it can't be done without significant compromises in AFR, since my cam has 8" idle vacuum but 15" cruise vacuum, and it's still on the transfer slots even at 60 mph/3000 rpm. I'm going to try playing with idle feed restrictors and see if I can live with the lean off-idle flat spot that will invariably result, but seriously thinking of putting the old 800 back on.
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Hang in there. Don't give up yet.
 
This what I did with my car today, body gaskets from Detroit muscle.

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72Dart6pack said:
Hang in there. Don't give up yet.
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Thanks... I've already got quite a few hours in it, taking the primary bowl & block off, drilling little brass setscrews, reinstall, drive, repeat...

It runs great, but also rich to pig-rich until I started tuning. If I didn't have an AFR gauge I'd be happy with the driveability (if not the mileage) :p Anyway it's basic physics. This larger carb only needs a tiny throttle opening to cruise, which is on the t-slots. It will always be richer than the old 4780-2 I converted to 4-corner and adjustable brass.
 
gonna drop the plow truck off at the diesel shop tonite, to have the sure grip rebuild

i always wondered why anyone would put a pegleg in a truck, ANY truck, but especially a 1 ton...turn out the clutches are just burnt out
and that at only a 1/4 million miles
 
Another session of carb tuning, posting findings and receiving advice... working with the main air bleeds today. (Current theory is too much overlap between the t-slot and the mains coming in). Now I have a nice lean 14-15:1 25-30 mph cruise, but the 60 mph cruise is still too fat at 12.5 (15" vac.) More throttle to 10" and it leans out to 14:1.

I went up another .003 on the MAB, but I'm tired of fooling with it today. And the clutch needs readjusting, engages right off the floor and hard to get into gear when stopped.
Filled the fuel cell again, 7.4 gallons used in 53 miles :steering:
 
I adjusted the clutch (hadn't tightened the jam nut on the master cylinder and I think the piston rod had rotated and shortened). Then I warmed it up and went for a tuning drive... I really wish I had an airport runway to drive on. 4000 rpm in 4th is 80 mph and it's just up on the cam then. Lower gears accelerate too fast to get steady readings on the AFR and vacuum gauge (besides, I have to be looking at the road!)

Also, I had been hearing a scraping noise from my left front brake (although it has always stopped straight). Figured it was just surface rust from sitting for long periods. I shouldn't admit this in public, but I'd put the inside pad on backwards so the metal back was against the rotor :eek: There is some scoring on the rotor, not surprisingly, but I just flipped the pad around and put the caliper back on. It still stops straight and fast but now the scraping is gone. That's about the second most dumbass thing I've done on this car! :rolleyes:
 
DrCharles said:
I adjusted the clutch (hadn't tightened the jam nut on the master cylinder and I think the piston rod had rotated and shortened). Then I warmed it up and went for a tuning drive... I really wish I had an airport runway to drive on. 4000 rpm in 4th is 80 mph and it's just up on the cam then. Lower gears accelerate too fast to get steady readings on the AFR and vacuum gauge (besides, I have to be looking at the road!)

Also, I had been hearing a scraping noise from my left front brake (although it has always stopped straight). Figured it was just surface rust from sitting for long periods. I shouldn't admit this in public, but I'd put the inside pad on backwards so the metal back was against the rotor :eek: There is some scoring on the rotor, not surprisingly, but I just flipped the pad around and put the caliper back on. It still stops straight and fast but now the scraping is gone. That's about the second most dumbass thing I've done on this car! :rolleyes:
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A good man admits his mistakes and moves forward.
 
Finally making progress on my 950 carb tune. I leaned the IFR way down (to .028). The T-slot is maybe even a little TOO lean with a tip-in flat spot. Also dropped the primary main jets 2 sizes. Now I can cruise at 3000 rpm, 15" vacuum, at 13.5. Would like to get to 14+ but I can live with that. Jets are down to #73 and I think one more step down will be good. I'll also have to drop the secondary jets to #84 with the existing .059 PVCR. Or maybe increase the PVCR. It's hard to tune on public roads with a car this speedy. :)

While driving gently about half a mile from home, I stepped on the clutch and something went "ting!" and the pedal stuck to the floor, with the clutch still engaged! Oh dear. :eek: Fortunately it was a simple roadside fix - the fancy Kep nut on the end of the clutch pedal stud under the dash had loosened every time I released the pedal, and once it fell off, the master cylinder pushrod popped off the stud.... replaced it with the original hex nut and split lockwasher. Whew.
 
DrCharles said:
Finally making progress on my 950 carb tune. I leaned the IFR way down (to .028). The T-slot is maybe even a little TOO lean with a tip-in flat spot. Also dropped the primary main jets 2 sizes. Now I can cruise at 3000 rpm, 15" vacuum, at 13.5. Would like to get to 14+ but I can live with that. Jets are down to #73 and I think one more step down will be good. I'll also have to drop the secondary jets to #84 with the existing .059 PVCR. Or maybe increase the PVCR. It's hard to tune on public roads with a car this speedy. :)

While driving gently about half a mile from home, I stepped on the clutch and something went "ting!" and the pedal stuck to the floor, with the clutch still engaged! Oh dear. :eek: Fortunately it was a simple roadside fix - the fancy Kep nut on the end of the clutch pedal stud under the dash had loosened every time I released the pedal, and once it fell off, the master cylinder pushrod popped off the stud.... replaced it with the original hex nut and split lockwasher. Whew.
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I'd be fixing that problem first. But sounds like your making huge progress. Wanna help me on a 6 pack when your done? It's only a few 2 bbls. Just kidding. I'm impressed with you patience. Keep moving forward.
 
Unfortunately, because my idle vacuum (8") is about half of the cruise vacuum (15"), and the t-slot (which is an air bleed above the throttle blade but a fuel source below the blade) it's near impossible to get it perfect!
Step on the gas, revs come up, vacuum gets higher (sucks harder on the slot) and at the same time, the t-slot is getting richer when it needs to be getting leaner. Can't repeal the laws of physics no matter how much I fiddle :realcrazy: Most people either live with some overrich or some flat spot.
Anyway, I am reminded of the apocryphal elementary school book report: "This book told me more about penguins than I care to know"
So I will read about your six-pack tuning adventures with interest, but I think I'll be busy that day! :p
 
My air bleed blanks came in today's mail, so I did a bit more tweaking and drilling. Reduced the slightly oversized .082 PIAB to .078, also one more step down on the primary jets to #72, and lowered the fuel level by three flats on both bowls. That should lean the cruise out at least 0.5 AFR or more, and also slightly richen the overlean tip-in when I went small on the IFR.

It's a beautiful sunny day and 66 degrees, but I just don't feel like more bouncing around on our crappy dirt/gravel roads (and trying to watch gauges while driving on the two-lane either). Maybe I'll try it tomorrow instead :rolleyes:
 
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DrCharles said:
My air bleed blanks came in today's mail, so I did a bit more tweaking and drilling. Reduced the slightly oversized .082 PIAB to .078, also one more step down on the primary jets to #72, and lowered the fuel level by three flats on both bowls. That should lean the cruise out at least 0.5 AFR or more, and also with the overlean tip-in when I went small on the IFR.

It's a beautiful sunny day and 66 degrees, but I just don't feel like more bouncing around on our crappy dirt/gravel roads (and trying to watch gauges while driving on the two-lane either). Maybe I'll try it tomorrow instead :rolleyes:
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You sound so close. Don't give up now. A few more tweaks and you'll have it. Good work so far. :)
 
Their was no way that greasy thing was going on my Motor. So I cleaned it up. (Maybe a little too much) Whoops.:eek:

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picked up my shortened DS for the GV and test fitted it. 35" cent > cent on the u-joints. fits perfect
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