Author Topic: 87 k10 350 tbi tuning?  (Read 7632 times)

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #60 on: April 05, 2023, 02:33:08 PM »
Well Captain, that makes the most sense, since the pump is at the bottom of the tank, and the rubber hose connects the hard line. I hear what sound like circulation, which is probably spraying out of the rubber hose, and accounts for such low pressure.

I found a inline fuel pump from a Benz I had, it measures 50 psi full throttle. Thinking about locating it post fuel filter where hard line converts to rubber.

I'll keep you posted, and THANKS!
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #61 on: April 21, 2023, 07:46:13 PM »
She Lives!!! ;D ;D ;D

So I placed a pump inline by extending the rubber fuel line, and back then back to the TBI.

It works on both tanks.

Haven't heard her run for months!!!
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Shifty

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Re: 87 k10 350 tbi tuning?
« Reply #62 on: April 22, 2023, 10:13:27 AM »
Good to hear that she's up and running!  Cheers!  :D
87 V20 Standard Cab Longbed (current)

87 R30 3+3 Longbed (days of yore)

98 C2500 ext cab longbed

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #63 on: April 23, 2023, 03:13:37 PM »
Thanks!

Took her up to the car wash for a long overdue scrubbing.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #64 on: May 19, 2023, 08:52:46 PM »
So I took her for some new sneakers on the rear dually's, and she started to choke up, lost power and threw code.

44, so I guess she's running lean? I already changed the 02 sensor.

Looking on ebay/amazon for a OBD1 right now.  >:(
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: 87 k10 350 tbi tuning?
« Reply #65 on: May 20, 2023, 06:49:41 PM »
Why did you use that fuel pump? You need to push the fuel not pull it and you need a steady 13 psi
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74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #66 on: May 21, 2023, 11:09:37 AM »
Well I didn't see this pump as a permanent fix. I will get the tank pumps replaced.

It would seem that under load the volume required is impeded by the hose decay between the tank pump and the pick up tube.

1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #67 on: May 22, 2023, 08:01:13 PM »
Another theory-

Probably had 2-3 gallons, so with the level so low, the secondary pump was most likely drawing air into the damaged hose.

Primary only delivers 5 psi at the moment, so we had a diluted mixture of air and gas.

I bought some 'catcleaner' additive, added 2 gallons, drove for 12 miles, mixed fwy and surface, avg 45-65 mph.

She cleared up nicely after about 5 miles. Filled her up with premium, now let's see if she passes smog... ::)

Oh, and the 32.00 OBD1 doesn't do anything but short 1+2, just like my paper clip!!! >:(
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline VileZambonie

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Re: 87 k10 350 tbi tuning?
« Reply #68 on: May 23, 2023, 05:40:50 PM »
Right, a code reader is not a scan tool so don't waste your money on one. "Premium" will not help with emissions. In fact it may cause your HC's to increase.
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              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #69 on: May 24, 2023, 10:04:23 AM »
So VZ, is there a OBD1 that actually scans? Or do we just have to count the blinky lights?
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Mike81K10

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Re: 87 k10 350 tbi tuning?
« Reply #70 on: May 24, 2023, 02:20:11 PM »
I have an INNOVA Scan Tool 5610 and it does very well on my vehicles made in the 2000s, as for 80s and 90s vehicles there may be additional attachments that can be purchased. It is used with my phone and does a lot. It will break down codes and helps to troubleshoot problems, has many features. You can look it up on line. There are others good ones as well I am sure.
"Tell me and I forget. Teach me and I remember. Involve me and I learn." -Benjamin Franklin

Offline VileZambonie

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                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Online Mr Diesel

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1976 C20 Crewcab, 6.2L/SM465
1982 K30 Crewcab , 427TD/TH400
1983 C30, 6.2L/TH400
1983 K30 Crewcab 454/700R4
1986 K10 350/400. 1989 K30 cab/chassis 454/SM465

Offline JohnnyPopper

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Re: 87 k10 350 tbi tuning?
« Reply #73 on: May 24, 2023, 09:03:34 PM »
Thx guys! Will let you know what happens!
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction