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Old 01-23-2020, 11:58 AM   #6176
Gregski
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Re: Restoring Rusty

and here is the driver side, again the bend right before the pipe goes over the rear axle

some day I will take out the grinder and re weld these spots, but not today, though my buddy Pontiac Mike says his pro muffler shop deliberately puts in drip holes in the state of the art exhaust systems they build for their customers to allow the condensation to drain, hmmm, am I on to something here by accident?
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Old 01-23-2020, 12:20 PM   #6177
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Re: Restoring Rusty

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Originally Posted by Gregski View Post
and here is the driver side, again the bend right before the pipe goes over the rear axle

some day I will take out the grinder and re weld these spots, but not today, though my buddy Pontiac Mike says his pro muffler shop deliberately puts in drip holes in the state of the art exhaust systems they build for their customers to allow the condensation to drain, hmmm, am I on to something here by accident?
If it's just a pinhole I'd leave it so the condensation will continue to drain out instead of rotting out the pipe
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Old 01-23-2020, 02:46 PM   #6178
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Re: Restoring Rusty

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If it's just a pinhole I'd leave it so the condensation will continue to drain out instead of rotting out the pipe
I started doing just that on muffler shop aluminized set-ups. I would drill a super small hole just to allow condensation somewhere to drain.
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Old 01-23-2020, 04:25 PM   #6179
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Re: Restoring Rusty

If you can't hear a pfff, pfff, pfff noise from the holes, they're probably OK as is.
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Old 01-26-2020, 12:49 PM   #6180
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Re: Restoring Rusty

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If you can't hear a pfff, pfff, pfff noise from the holes, they're probably OK as is.
thanks
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Old 01-26-2020, 01:02 PM   #6181
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Re: Restoring Rusty

so I've been driving myself crazy over the past few months trying to tune out a small Idle Issue I have, not sure it's quite a hunting idle, but here's what the problem is:

Either in park or in drive my RPMs go up 50 or down 50. So I should idle at 550 RPM in Park, well I can see it drop to like 490 or go up to like 590 I also see timing go from 19* where it should be down to 16* or as high as 25*

I understand that the PCM adjusts the timing via the Idle Adaptive Spark Control aka Overspeed and Underspeed to pull the RPMs back to the desired Idle RPM, but I don't know what is causing the RPMs to be off in the first place.

My MAF grams per second may very 5.1 to 5.2 (and the frequency goes from 2527 to 2510 for example) and timing goes 21* to 20* so is that it? is that enough of a change and what can be done to make the MAF less sporatic, is it time for a new MAF?

My MAF is attached to the OEM air intake so it is the stock distance from the throttle body. I am using a cone air filter though i tried the OEM air box and stock air filter as well. Also I tried cleaning my MAF, I also tried a second MAF (same part number) I happen to have a spare and of course I re calibrated it, as it was reading up to 12% lean.

I will probably post this in the LS Swap section as well for better chance of someone seeing it
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Old 01-28-2020, 11:48 AM   #6182
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Re: Restoring Rusty

What are your O2 sensor readings doing?
Can you graph your Idle speed, MAF, O2, IAC, EGR, Timing and maybe fuel tank pressure along with fuel pressure, if you have those two available, in realtime and log them for playback with your diag package?
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1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8


RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
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Old 02-06-2020, 07:55 PM   #6183
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Re: Restoring Rusty

just a quick update spoke to a few pro tuners / instructors, and this appears to be normal, here's a quote from Andre Simon of HP Academy

"Yes that's totally normal. The ignition timing is used to help control the idle speed and as such it will jump around significantly in order to control engine torque."
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Old 02-07-2020, 12:38 AM   #6184
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Re: Restoring Rusty

Yours a fly by wire or cable pedal?

Friend did an LS in a c60 with 6 speed and it would stall randomly at lights and ended up having to relearn the pedal parameters
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Old 02-07-2020, 09:11 AM   #6185
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Re: Restoring Rusty

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Originally Posted by KQQL IT View Post
Yours a fly by wire or cable pedal?

Friend did an LS in a c60 with 6 speed and it would stall randomly at lights and ended up having to relearn the pedal parameters
Mine is a cable throttle body, less complex. I've heard of the condition you are describing on drive by wire applications, see Andre from HP Academy explain how to address it here using the

Engine \ Idle \ Airflow \ Effective Area

Percent Max
Percent Max - Brake


217 | Idle Tuning HP Tuners - GM/HP Tuners
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Old 02-08-2020, 11:43 AM   #6186
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Re: Restoring Rusty

I have been gone for two years and when I come back to check in and BOOM you done went and done it.

As usual you jumped in with both feet, made a mess and then made it awesome. Rusty is looking great.
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Old 02-08-2020, 12:21 PM   #6187
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Re: Restoring Rusty

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I have been gone for two years and when I come back to check in and BOOM you done went and done it.

As usual you jumped in with both feet, made a mess and then made it awesome. Rusty is looking great.
Thank you, welcome back to the circus act, and that's what you git for leaving!
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Old 02-23-2020, 01:01 PM   #6188
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Re: Restoring Rusty - Front Brakes Rotors & Pads

looks like I finally get to replace the front brakes on Rusty for the first time

so learned they came in two flavors light duty and heavy duty, I thought I had the heavy duty ones but judging by the bearing part numbers I don't think I do

the original rotors had a nice rubber seal on the inner bearing the new replacement ones don't - shocking!

new pads don't come with the inner pad clip that you snap into the single piston to help you hold the pad in place, and one of my old ones broke so that installation was fun, as a third hand would sure have come in handy, lol
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Old 02-24-2020, 11:57 AM   #6189
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Re: Restoring Rusty

I'm not a fan of the AutoZone or National Chinese bearings. Eastern Europe is just as good as USA made and I'd take Japan, Korea, and Taiwan sourced bearings over those made in mainland China or India. FAG and some SKF bearings are still made outside of China and India... and some Timken taper bearings are still made in the USA or they are old stock.
I just bought six Timken SET6 bearing sets for the tine shafts on three Troy Bilt Horse I tillers and one Horse III tiller that I'm rebuilding along with ten Timken SET2 for the main shafts and eight sets of FAG 6201 bearings etched Poland. The Timken bearings are all etched USA and they cost around $8 each.

The parts guy at AutoZone couldn't find the proper grease seal? It's a separate part.

The GM part number for the grease seal on the 1974 GMC RWD front brakes should be 3857731 if the GM parts books are to be believed.
AC Delco lists 290269 for LD front brake rotor grease seal. That doesn't cross to the GM part number in the 73-78 parts books... It's possible I looked it up incorrectly but it lists 73-78 CP- 2,3, M.H.C and CP-1 on page 943 of the parts book.
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1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8


RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...Please include at least the year and model in your threads. It'll be easier to answer your questions.
And please let us know if and how your repairs were successful.

Last edited by hatzie; 02-24-2020 at 03:34 PM.
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